Search results

Title: Impact of Spaceflight and Artificial Gravity on the Mouse Retina: Biochemical and Proteomic Analysis..
Creator: Mao, Xiao W, Byrum, Stephanie, Nishiyama, Nina C, Pecaut, Michael J, Sridharan, Vijayalakshmi, Boerma, Marjan, Tackett, Alan J, Shiba, Dai, Shirakawa, Masaki, Takahashi, Satoru,...
Show moreMao, Xiao W, Byrum, Stephanie, Nishiyama, Nina C, Pecaut, Michael J, Sridharan, Vijayalakshmi, Boerma, Marjan, Tackett, Alan J, Shiba, Dai, Shirakawa, Masaki, Takahashi, Satoru, Delp, Michael D
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Abstract/Description: Astronauts are reported to have experienced some impairment in visual acuity during their mission on the International Space Station (ISS) and after they returned to Earth. There is emerging evidence that changes in vision may involve alterations in ocular structure and function. To investigate possible mechanisms, changes in protein expression profiles and oxidative stress-associated apoptosis were examined in mouse ocular tissue after spaceflight. Nine-week-old male C57BL/6 mice ( = 12)...
Show moreAstronauts are reported to have experienced some impairment in visual acuity during their mission on the International Space Station (ISS) and after they returned to Earth. There is emerging evidence that changes in vision may involve alterations in ocular structure and function. To investigate possible mechanisms, changes in protein expression profiles and oxidative stress-associated apoptosis were examined in mouse ocular tissue after spaceflight. Nine-week-old male C57BL/6 mice ( = 12) were launched from the Kennedy Space Center on a SpaceX rocket to the ISS for a 35-day mission. The animals were housed in the mouse Habitat Cage Unit (HCU) in the Japan Aerospace Exploration Agency (JAXA) "Kibo" facility on the ISS. The flight mice lived either under an ambient microgravity condition (µg) or in a centrifugal habitat unit that produced 1 artificial gravity (µg + 1 ). Habitat control (HC) and vivarium control mice lived on Earth in HCUs or normal vivarium cages, respectively. Quantitative assessment of ocular tissue demonstrated that the µg group induced significant apoptosis in the retina vascular endothelial cells compared to all other groups ( < 0.05) that was 64% greater than that in the HC group. Proteomic analysis showed that many key pathways responsible for cell death, cell repair, inflammation, and metabolic stress were significantly altered in µg mice compared to HC animals. Additionally, there were more significant changes in regulated protein expression in the µg group relative to that in the µg + 1 group. These data provide evidence that spaceflight induces retinal apoptosis of vascular endothelial cells and changes in retinal protein expression related to cellular structure, immune response and metabolic function, and that artificial gravity (AG) provides some protection against these changes. These retinal cellular responses may affect blood⁻retinal barrier (BRB) integrity, visual acuity, and impact the potential risk of developing late retinal degeneration.
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Date Issued: 2018-08-28
Identifier: FSU_pmch_30154332, 10.3390/ijms19092546, PMC6165321, 30154332, 30154332, ijms19092546
Format: Citation

Title: Targeted disruption of the endogenous zebrafish locus as models of rapid rod photoreceptor degeneration.
Creator: Zelinka, Christopher P, Sotolongo-Lopez, Mailin, Fadool, James M
Abstract/Description: Retinitis pigmentosa (RP) is a collection of genetic disorders that results in the degeneration of light-sensitive photoreceptor cells, leading to blindness. RP is associated with more than 70 loci that may display dominant or recessive modes of inheritance, but mutations in the gene encoding the visual pigment rhodopsin (RHO) are the most frequent cause. In an effort to develop precise mutations in zebrafish as novel models of photoreceptor degeneration, we describe the generation and...
Show moreRetinitis pigmentosa (RP) is a collection of genetic disorders that results in the degeneration of light-sensitive photoreceptor cells, leading to blindness. RP is associated with more than 70 loci that may display dominant or recessive modes of inheritance, but mutations in the gene encoding the visual pigment rhodopsin (RHO) are the most frequent cause. In an effort to develop precise mutations in zebrafish as novel models of photoreceptor degeneration, we describe the generation and germline transmission of a series of novel clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-induced insertion and deletion (indel) mutations in the major zebrafish locus, . One- or two-cell staged zebrafish embryos were microinjected with in vitro transcribed mRNA encoding Cas9 and a single guide RNA (gRNA). Mutations were detected by restriction fragment length polymorphism (RFLP) and DNA sequence analyses in injected embryos and offspring. Immunolabeling with rod- and cone-specific antibodies was used to test for histological and cellular changes. Using gRNAs that targeted highly conserved regions of , a series of dominant and recessive alleles were recovered that resulted in the rapid degeneration of rod photoreceptors. No effect on cones was observed. Targeting the 5'-coding sequence of led to the recovery of several indels similar to disease-associated alleles. A frame shift mutation leading to a premature stop codon (T17*) resulted in rod degeneration when brought to homozygosity. Immunoblot and fluorescence labeling with a Rho-specific antibody suggest that this is indeed a null allele, illustrating that the Rho expression is essential for rod survival. Two in-frame mutations were recovered that disrupted the highly conserved N-linked glycosylation consensus sequence at N15. Larvae heterozygous for either of the alleles demonstrated rapid rod degeneration. Targeting of the 3'-coding region of resulted in the recovery of an allele encoding a premature stop codon (S347*) upstream of the conserved VSPA sorting sequence and a second in-frame allele that disrupted the putative phosphorylation site at S339. Both alleles resulted in rod death in a dominant inheritance pattern. Following the loss of the targeting sequence, immunolabeling for Rho was no longer restricted to the rod outer segment, but it was also localized to the plasma membrane. The efficiency of CRISPR/Cas9 for gene targeting, coupled with the large number of mutations associated with RP, provided a backdrop for the rapid isolation of novel alleles in zebrafish that phenocopy disease. These novel lines will provide much needed in-vivo models for high throughput screens of compounds or genes that protect from photoreceptor degeneration.
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Date Issued: 2018-08-27
Identifier: FSU_pmch_30210230, PMC6128699, 30210230, 30210230
Format: Citation

Title: Phylogenomics uncovers early hybridization and adaptive loci shaping the radiation of Lake Tanganyika cichlid fishes.
Creator: Irisarri, Iker, Singh, Pooja, Koblmüller, Stephan, Torres-Dowdall, Julián, Henning, Frederico, Franchini, Paolo, Fischer, Christoph, Lemmon, Alan R, Lemmon, Emily Moriarty,...
Show moreIrisarri, Iker, Singh, Pooja, Koblmüller, Stephan, Torres-Dowdall, Julián, Henning, Frederico, Franchini, Paolo, Fischer, Christoph, Lemmon, Alan R, Lemmon, Emily Moriarty, Thallinger, Gerhard G, Sturmbauer, Christian, Meyer, Axel
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Abstract/Description: Lake Tanganyika is the oldest and phenotypically most diverse of the three East African cichlid fish adaptive radiations. It is also the cradle for the younger parallel haplochromine cichlid radiations in Lakes Malawi and Victoria. Despite its evolutionary significance, the relationships among the main Lake Tanganyika lineages remained unresolved, as did the general timescale of cichlid evolution. Here, we disentangle the deep phylogenetic structure of the Lake Tanganyika radiation using...
Show moreLake Tanganyika is the oldest and phenotypically most diverse of the three East African cichlid fish adaptive radiations. It is also the cradle for the younger parallel haplochromine cichlid radiations in Lakes Malawi and Victoria. Despite its evolutionary significance, the relationships among the main Lake Tanganyika lineages remained unresolved, as did the general timescale of cichlid evolution. Here, we disentangle the deep phylogenetic structure of the Lake Tanganyika radiation using anchored phylogenomics and uncover hybridization at its base, as well as early in the haplochromine radiation. This suggests that hybridization might have facilitated these speciation bursts. Time-calibrated trees support that the radiation of Tanganyika cichlids coincided with lake formation and that Gondwanan vicariance concurred with the earliest splits in the cichlid family tree. Genes linked to key innovations show signals of introgression or positive selection following colonization of lake habitats and species' dietary adaptations are revealed as major drivers of colour vision evolution. These findings shed light onto the processes shaping the evolution of adaptive radiations.
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Date Issued: 2018-08-08
Identifier: FSU_pmch_30089797, 10.1038/s41467-018-05479-9, PMC6082878, 30089797, 30089797, 10.1038/s41467-018-05479-9
Format: Citation

Title: The Application of Dynamic Models to the Exploration of -AR Overactivation as a Cause of Heart Failure.
Creator: Wang, Xiaoyun, Zhao, Min, Wang, Xiaoqiang, Li, Shuping, Cao, Ning, Liu, Huirong
Abstract/Description: High titer of -adrenoreceptor autoantibodies (-AA) has been reported to appear in heart failure patients. It induces sustained -adrenergic receptor (-AR) activation which leads to heart failure (HF), but the mechanism is as yet unclear. In order to investigate the mechanisms causing -AR non-desensitization, we studied the beating frequency of the neonatal rat cardiomyocytes (NRCMs) under different conditions (an injection of isoprenaline (ISO) for one group and -AA for the other) and...
Show moreHigh titer of -adrenoreceptor autoantibodies (-AA) has been reported to appear in heart failure patients. It induces sustained -adrenergic receptor (-AR) activation which leads to heart failure (HF), but the mechanism is as yet unclear. In order to investigate the mechanisms causing -AR non-desensitization, we studied the beating frequency of the neonatal rat cardiomyocytes (NRCMs) under different conditions (an injection of isoprenaline (ISO) for one group and -AA for the other) and established three dynamic models in order to best describe the true relationships shown in medical experiments; one model used a control group of healthy rats; then in HF rats one focused on conformation changes in -AR; the other examined interaction between -AR and -adrenergic receptors (-AR). Comparing the experimental data and corresponding Akaike information criterion (AIC) values, we concluded that the interaction model was the most likely mechanism. We used mathematical methods to explore the mechanism for the development of heart failure and to find potential targets for prevention and treatment. The aim of the paper was to provide a strong theoretical basis for the clinical development of personalized treatment programs. We also carried out sensitivity analysis of the initial concentration -AA and found that they had a noticeable effect on the fitting results.
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Date Issued: 2018-07-30
Identifier: FSU_pmch_30154911, 10.1155/2018/1613290, PMC6091447, 30154911, 30154911
Format: Citation

Title: Quantitative Morphological Variation in the Developing Wing.
Creator: Matamoro-Vidal, Alexis, Huang, Yunxian, Salazar-Ciudad, Isaac, Shimmi, Osamu, Houle, David
Abstract/Description: Quantitative genetic variation in morphology is pervasive in all species and is the basis for the evolution of differences among species. The measurement of morphological form in adults is now beginning to be combined with comparable measurements of form during development. Here we compare the shape of the developing wing to its adult form in a holometabolous insect, We used protein expression patterns to measure shape in the developing precursors of the final adult wing. Three developmental...
Show moreQuantitative genetic variation in morphology is pervasive in all species and is the basis for the evolution of differences among species. The measurement of morphological form in adults is now beginning to be combined with comparable measurements of form during development. Here we compare the shape of the developing wing to its adult form in a holometabolous insect, We used protein expression patterns to measure shape in the developing precursors of the final adult wing. Three developmental stages were studied: late larval third instar, post-pupariation and in the adult fly. We studied wild-type animals in addition to mutants of two genes ( and ) that have known effects on adult wing shape and size. Despite experimental noise related to the difficulty of comparing developing structures, we found consistent differences in wing shape and size at each developmental stage between genotypes. Quantitative comparisons of variation arising at different developmental stages with the variation in the final structure enable us to determine when variation arises, and to generate hypotheses about the causes of that variation. In addition we provide linear rules allowing us to link wing morphology in the larva, with wing morphology in the pupa. Our approach provides a framework to analyze quantitative morphological variation in the developing fly wing. This framework should help to characterize the natural variation of the larval and pupal wing shape, and to measure the contribution of the processes occurring during these developmental stages to the natural variation in adult wing morphology.
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Date Issued: 2018-07-02
Identifier: FSU_pmch_29844017, 10.1534/g3.118.200372, PMC6027878, 29844017, 29844017, g3.118.200372
Format: Citation

Title: Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions..
Creator: Schoenfelder, Stefan, Javierre, Biola-Maria, Furlan-Magaril, Mayra, Wingett, Steven W, Fraser, Peter
Abstract/Description: The three-dimensional organization of the genome is linked to its function. For example, regulatory elements such as transcriptional enhancers control the spatio-temporal expression of their target genes through physical contact, often bridging considerable (in some cases hundreds of kilobases) genomic distances and bypassing nearby genes. The human genome harbors an estimated one million enhancers, the vast majority of which have unknown gene targets. Assigning distal regulatory regions to...
Show moreThe three-dimensional organization of the genome is linked to its function. For example, regulatory elements such as transcriptional enhancers control the spatio-temporal expression of their target genes through physical contact, often bridging considerable (in some cases hundreds of kilobases) genomic distances and bypassing nearby genes. The human genome harbors an estimated one million enhancers, the vast majority of which have unknown gene targets. Assigning distal regulatory regions to their target genes is thus crucial to understand gene expression control. We developed Promoter Capture Hi-C (PCHi-C) to enable the genome-wide detection of distal promoter-interacting regions (PIRs), for all promoters in a single experiment. In PCHi-C, highly complex Hi-C libraries are specifically enriched for promoter sequences through in-solution hybrid selection with thousands of biotinylated RNA baits complementary to the ends of all promoter-containing restriction fragments. The aim is to then pull-down promoter sequences and their frequent interaction partners such as enhancers and other potential regulatory elements. After high-throughput paired-end sequencing, a statistical test is applied to each promoter-ligated restriction fragment to identify significant PIRs at the restriction fragment level. We have used PCHi-C to generate an atlas of long-range promoter interactions in dozens of human and mouse cell types. These promoter interactome maps have contributed to a greater understanding of mammalian gene expression control by assigning putative regulatory regions to their target genes and revealing preferential spatial promoter-promoter interaction networks. This information also has high relevance to understanding human genetic disease and the identification of potential disease genes, by linking non-coding disease-associated sequence variants in or near control sequences to their target genes.
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Date Issued: 2018-06-28
Identifier: FSU_pmch_30010637, 10.3791/57320, PMC6102006, 30010637, 30010637
Format: Citation

Title: Isotope niche dimension and trophic overlap between bigheaded carps and native filter-feeding fish in the lower Missouri River, USA.
Creator: Wang, Jianzhu, Chapman, Duane, Xu, Jun, Wang, Yang, Gu, Binhe
Abstract/Description: Stable carbon and nitrogen isotope values (δ13C and δ15N) were used to evaluate trophic niche overlap between two filter-feeding fishes (known together as bigheaded carp) native to China, silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), and three native filter-feeding fish including bigmouth buffalo (Ictiobus cyprinellus), gizzard shad (Dorosoma cepedianum) and paddlefish (Polyodon spathula) in the lower Missouri River, USA, using the Bayesian Stable...
Show moreStable carbon and nitrogen isotope values (δ13C and δ15N) were used to evaluate trophic niche overlap between two filter-feeding fishes (known together as bigheaded carp) native to China, silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), and three native filter-feeding fish including bigmouth buffalo (Ictiobus cyprinellus), gizzard shad (Dorosoma cepedianum) and paddlefish (Polyodon spathula) in the lower Missouri River, USA, using the Bayesian Stable Isotope in R statistics. Results indicate that except for bigmouth buffalo, all species displayed similar trophic niche size and trophic diversity. Bigmouth buffalo occupied a small trophic niche and had the greatest trophic overlap with silver carp (93.6%) and bighead carp (94.1%) followed by gizzard shad (91.0%). Paddlefish had a trophic niche which relied on some resources different from those used by other species, and therefore had the lowest trophic overlap with bigheaded carp and other two native fish. The trophic overlap by bigheaded carp onto native fish was typically stronger than the reverse effects from native fish. Average niche overlap between silver carp and native species was as high as 71%, greater than niche overlap between bighead carp and native fish (64%). Our findings indicate that bigheaded carps are a potential threat to a diverse and stable native fish community.
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Date Issued: 2018-05-21
Identifier: FSU_pmch_29782547, 10.1371/journal.pone.0197584, PMC5962084, 29782547, 29782547, PONE-D-17-44424
Format: Citation

Title: mTOR signaling regulates central and peripheral circadian clock function.
Creator: Ramanathan, Chidambaram, Kathale, Nimish D, Liu, Dong, Lee, Choogon, Freeman, David A, Hogenesch, John B, Cao, Ruifeng, Liu, Andrew C
Abstract/Description: The circadian clock coordinates physiology and metabolism. mTOR (mammalian/mechanistic target of rapamycin) is a major intracellular sensor that integrates nutrient and energy status to regulate protein synthesis, metabolism, and cell growth. Previous studies have identified a key role for mTOR in regulating photic entrainment and synchrony of the central circadian clock in the suprachiasmatic nucleus (SCN). Given that mTOR activities exhibit robust circadian oscillations in a variety of...
Show moreThe circadian clock coordinates physiology and metabolism. mTOR (mammalian/mechanistic target of rapamycin) is a major intracellular sensor that integrates nutrient and energy status to regulate protein synthesis, metabolism, and cell growth. Previous studies have identified a key role for mTOR in regulating photic entrainment and synchrony of the central circadian clock in the suprachiasmatic nucleus (SCN). Given that mTOR activities exhibit robust circadian oscillations in a variety of tissues and cells including the SCN, here we continued to investigate the role of mTOR in orchestrating autonomous clock functions in central and peripheral circadian oscillators. Using a combination of genetic and pharmacological approaches we show that mTOR regulates intrinsic clock properties including period and amplitude. In peripheral clock models of hepatocytes and adipocytes, mTOR inhibition lengthens period and dampens amplitude, whereas mTOR activation shortens period and augments amplitude. Constitutive activation of mTOR in Tsc2-/-fibroblasts elevates levels of core clock proteins, including CRY1, BMAL1 and CLOCK. Serum stimulation induces CRY1 upregulation in fibroblasts in an mTOR-dependent but Bmal1- and Period-independent manner. Consistent with results from cellular clock models, mTOR perturbation also regulates period and amplitude in the ex vivo SCN and liver clocks. Further, mTOR heterozygous mice show lengthened circadian period of locomotor activity in both constant darkness and constant light. Together, these results support a significant role for mTOR in circadian timekeeping and in linking metabolic states to circadian clock functions.
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Date Issued: 2018-05-11
Identifier: FSU_pmch_29750810, 10.1371/journal.pgen.1007369, PMC5965903, 29750810, 29750810, PGENETICS-D-17-02178
Format: Citation

Title: NADPH Oxidases and Mitochondria in Vascular Senescence.
Creator: Salazar, Gloria
Abstract/Description: Aging is the major risk factor in the development of cardiovascular diseases (CVDs), including hypertension, atherosclerosis, and myocardial infarction. Oxidative stress caused by overproduction of reactive oxygen species (ROS) and/or by reduced expression of antioxidant enzymes is a major contributor to the progression of vascular senescence, pathologic remodeling of the vascular wall, and disease. Both oxidative stress and inflammation promote the development of senescence, a process by...
Show moreAging is the major risk factor in the development of cardiovascular diseases (CVDs), including hypertension, atherosclerosis, and myocardial infarction. Oxidative stress caused by overproduction of reactive oxygen species (ROS) and/or by reduced expression of antioxidant enzymes is a major contributor to the progression of vascular senescence, pathologic remodeling of the vascular wall, and disease. Both oxidative stress and inflammation promote the development of senescence, a process by which cells stop proliferating and become dysfunctional. This review focuses on the role of the mitochondria and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidases Nox1 and Nox4 in vascular senescence, and their contribution to the development of atherosclerosis. Recent findings are reviewed, supporting a critical role of the mitochondrial regulator peroxisome proliferator-activated receptor gamma (PPARγ) coactivator-1α (PGC-1α), the inflammatory gene nuclear factor κB (NF-κB), zinc, the zinc transporters (ZnTs) ZnT3 and ZnT10, and angiotensin II (Ang II) in mitochondrial function, and their role in telomere stability, which provides new mechanistic insights into a previously proposed unified theory of aging.
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Date Issued: 2018-04-29
Identifier: FSU_pmch_29710840, 10.3390/ijms19051327, PMC5983750, 29710840, 29710840, ijms19051327
Format: Citation

Title: 14-3-3 Proteins in Glutamatergic Synapses.
Creator: Zhang, Jiajing, Zhou, Yi
Abstract/Description: The 14-3-3 proteins are a family of proteins that are highly expressed in the brain and particularly enriched at synapses. Evidence accumulated in the last two decades has implicated 14-3-3 proteins as an important regulator of synaptic transmission and plasticity. Here, we will review previous and more recent research that has helped us understand the roles of 14-3-3 proteins at glutamatergic synapses. A key challenge for the future is to delineate the 14-3-3-dependent molecular pathways...
Show moreThe 14-3-3 proteins are a family of proteins that are highly expressed in the brain and particularly enriched at synapses. Evidence accumulated in the last two decades has implicated 14-3-3 proteins as an important regulator of synaptic transmission and plasticity. Here, we will review previous and more recent research that has helped us understand the roles of 14-3-3 proteins at glutamatergic synapses. A key challenge for the future is to delineate the 14-3-3-dependent molecular pathways involved in regulating synaptic functions.
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Date Issued: 2018-04-23
Identifier: FSU_pmch_29849571, 10.1155/2018/8407609, PMC5937437, 29849571, 29849571
Format: Citation

Title: Hippocampal protein kinase D1 is necessary for DHPG-induced learning and memory impairments in rats.
Creator: Wang, Wei, Duclot, Florian, Groveman, Bradley R, Carrier, Nicole, Qiao, Haifa, Fang, Xiao-Qian, Wang, Hui, Xin, Wenkuan, Jiang, Xing-Hong, Salter, Michael W, Ding, Xin-Sheng,...
Show moreWang, Wei, Duclot, Florian, Groveman, Bradley R, Carrier, Nicole, Qiao, Haifa, Fang, Xiao-Qian, Wang, Hui, Xin, Wenkuan, Jiang, Xing-Hong, Salter, Michael W, Ding, Xin-Sheng, Kabbaj, Mohamed, Yu, Xian-Min
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Abstract/Description: Understanding molecular mechanisms underlying the induction of learning and memory impairments remains a challenge. Recent investigations have shown that the activation of group I mGluRs (mGluR1 and mGluR5) in cultured hippocampal neurons by application of (S)-3,5-Dihydroxyphenylglycine (DHPG) causes the regulated internalization of N-methyl-D-aspartate receptors (NMDARs), which subsequently activates protein kinase D1 (PKD1). Through phosphorylating the C-terminals of the NMDAR GluN2...
Show moreUnderstanding molecular mechanisms underlying the induction of learning and memory impairments remains a challenge. Recent investigations have shown that the activation of group I mGluRs (mGluR1 and mGluR5) in cultured hippocampal neurons by application of (S)-3,5-Dihydroxyphenylglycine (DHPG) causes the regulated internalization of N-methyl-D-aspartate receptors (NMDARs), which subsequently activates protein kinase D1 (PKD1). Through phosphorylating the C-terminals of the NMDAR GluN2 subunits, PKD1 down-regulates the activity of remaining (non-internalized) surface NMDARs. The knockdown of PKD1 does not affect the DHPG-induced inhibition of AMPA receptor-mediated miniature excitatory post-synaptic currents (mEPSCs) but prevents the DHPG-induced inhibition of NMDAR-mediated mEPSCs in vitro. Thus, we investigated the in vivo effects of bilateral infusions of DHPG into the hippocampal CA1 area of rats in the Morris water maze (MWM) and the novel object discrimination (NOD) tests. A total of 300 adult male Sprague Dawley rats (250-280 g) were used for behavioral tests. One hundred ninety four were used in MWM test and the other 106 rats in the NOD test. Following one week of habituation to the vivarium, rats were bilaterally implanted under deep anesthesia with cannulas aimed at the CA1 area of the hippocampus (CA1 coordinates in mm from Bregma: AP -3.14; lateral +/-2; DV -3.0). Through implanted cannulas artificial cerebrospinal fluid (ACSF), the group1 mGluR antagonist 6-Methyl-2-(phenylethynyl)pyridine (MPEP), the dynamin-dependent internalization inhibitor Dynasore, or the PKD1 inhibitor CID755673 were infused into the bilateral hippocampal CA1 areas (2 μL per side, over 5 min). The effects of these infusions and the effects of PKD1 knockdown were examined in MWM or NOD test. DHPG infusion increased the latency to reach the platform in the MWM test and reduced the preference for the novel object in the NOD task. We found that the DHPG effects were dose-dependent and could be maintained for up to 2 days. Notably, these effects could be prevented by pre-infusion of the group1 mGluR antagonist MPEP, the dynamin-dependent internalization inhibitor Dynasore, the PKD1 inhibitor CID755673, or by PKD1 knockdown in the hippocampal CA1 area. Altogether, these findings provide direct evidence that PKD1-mediated signaling may play a critical role in the induction of learning and memory impairments by DHPG infusion into the hippocampal CA1 area.
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Date Issued: 2018-04-03
Identifier: FSU_pmch_29614089, 10.1371/journal.pone.0195095, PMC5882104, 29614089, 29614089, PONE-D-17-33748
Format: Citation

Title: Effects of pharmacologic sclerostin inhibition or testosterone administration on soleus muscle atrophy in rodents after spinal cord injury.
Creator: Phillips, Ean G, Beggs, Luke A, Ye, Fan, Conover, Christine F, Beck, Darren T, Otzel, Dana M, Ghosh, Payal, Bassit, Anna C F, Borst, Stephen E, Yarrow, Joshua F
Abstract/Description: Sclerostin is a circulating osteocyte-derived glycoprotein that negatively regulates Wnt-signaling after binding the LRP5/LRP6 co-receptors. Pharmacologic sclerostin inhibition produces bone anabolic effects after spinal cord injury (SCI), however, the effects of sclerostin-antibody (Scl-Ab) on muscle morphology remain unknown. In comparison, androgen administration produces bone antiresorptive effects after SCI and some, but not all, studies have reported that testosterone treatment...
Show moreSclerostin is a circulating osteocyte-derived glycoprotein that negatively regulates Wnt-signaling after binding the LRP5/LRP6 co-receptors. Pharmacologic sclerostin inhibition produces bone anabolic effects after spinal cord injury (SCI), however, the effects of sclerostin-antibody (Scl-Ab) on muscle morphology remain unknown. In comparison, androgen administration produces bone antiresorptive effects after SCI and some, but not all, studies have reported that testosterone treatment ameliorates skeletal muscle atrophy in this context. Our purposes were to determine whether Scl-Ab prevents hindlimb muscle loss after SCI and compare the effects of Scl-Ab to testosterone enanthate (TE), an agent with known myotrophic effects. Male Sprague-Dawley rats aged 5 months received: (A) SHAM surgery (T8 laminectomy), (B) moderate-severe contusion SCI, (C) SCI+TE (7.0 mg/wk, im), or (D) SCI+Scl-Ab (25 mg/kg, twice weekly, sc). Twenty-one days post-injury, SCI animals exhibited a 31% lower soleus mass in comparison to SHAM, accompanied by >50% lower soleus muscle fiber cross-sectional area (fCSA) (p<0.01 for all fiber types). Scl-Ab did not prevent soleus atrophy, consistent with the relatively low circulating sclerostin concentrations and with the 91-99% lower LRP5/LRP6 gene expressions in soleus versus tibia (p<0.001), a tissue with known anabolic responsiveness to Scl-Ab. In comparison, TE partially prevented soleus atrophy and increased levator ani/bulbocavernosus (LABC) mass by 30-40% (p<0.001 vs all groups). The differing myotrophic responsiveness coincided with a 3-fold higher androgen receptor gene expression in LABC versus soleus (p<0.01). This study provides the first direct evidence that Scl-Ab does not prevent soleus muscle atrophy in rodents after SCI and suggests that variable myotrophic responses in rodent muscles after androgen administration are influenced by androgen receptor expression.
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Date Issued: 2018-03-26
Identifier: FSU_pmch_29579075, 10.1371/journal.pone.0194440, PMC5868788, 29579075, 29579075, PONE-D-17-24505
Format: Citation

Title: Advancing behavioural genomics by considering timescale.
Creator: Rittschof, Clare C, Hughes, Kimberly A
Abstract/Description: Animal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain...
Show moreAnimal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain genomic regulatory mechanisms may predict the timescale of an environmental effect on behaviour. This temporally minded approach could inform both organismal and evolutionary questions ranging from the remediation of early life social trauma to understanding the evolution of trait plasticity.
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Date Issued: 2018-02-12
Identifier: FSU_pmch_29434301, 10.1038/s41467-018-02971-0, PMC5809431, 29434301, 29434301, 10.1038/s41467-018-02971-0
Format: Citation

Title: Single-cell replication profiling to measure stochastic variation in mammalian replication timing.
Creator: Dileep, Vishnu, Gilbert, David M
Abstract/Description: Mammalian DNA replication is regulated via multi-replicon segments that replicate in a defined temporal order during S-phase. Further, early/late replication of RDs corresponds to active/inactive chromatin interaction compartments. Although replication origins are selected stochastically, variation in replication timing is poorly understood. Here we devise a strategy to measure variation in replication timing using DNA copy number in single mouse embryonic stem cells. We find that borders...
Show moreMammalian DNA replication is regulated via multi-replicon segments that replicate in a defined temporal order during S-phase. Further, early/late replication of RDs corresponds to active/inactive chromatin interaction compartments. Although replication origins are selected stochastically, variation in replication timing is poorly understood. Here we devise a strategy to measure variation in replication timing using DNA copy number in single mouse embryonic stem cells. We find that borders between replicated and unreplicated DNA are highly conserved between cells, demarcating active and inactive compartments of the nucleus. Fifty percent of replication events deviated from their average replication time by ± 15% of S phase. This degree of variation is similar between cells, between homologs within cells and between all domains genomewide, regardless of their replication timing. These results demonstrate that stochastic variation in replication timing is independent of elements that dictate timing or extrinsic environmental variation.
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Date Issued: 2018-01-30
Identifier: FSU_pmch_29382831, 10.1038/s41467-017-02800-w, PMC5789892, 29382831, 29382831, 10.1038/s41467-017-02800-w
Format: Citation

Title: Impacts of the Deepwater Horizon oil spill evaluated using an end-to-end ecosystem model.
Creator: Ainsworth, Cameron H, Paris, Claire B, Perlin, Natalie, Dornberger, Lindsey N, Patterson, William F, Chancellor, Emily, Murawski, Steve, Hollander, David, Daly, Kendra, Romero,...
Show moreAinsworth, Cameron H, Paris, Claire B, Perlin, Natalie, Dornberger, Lindsey N, Patterson, William F, Chancellor, Emily, Murawski, Steve, Hollander, David, Daly, Kendra, Romero, Isabel C, Coleman, Felicia, Perryman, Holly
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Abstract/Description: We use a spatially explicit biogeochemical end-to-end ecosystem model, Atlantis, to simulate impacts from the Deepwater Horizon oil spill and subsequent recovery of fish guilds. Dose-response relationships with expected oil concentrations were utilized to estimate the impact on fish growth and mortality rates. We also examine the effects of fisheries closures and impacts on recruitment. We validate predictions of the model by comparing population trends and age structure before and after the...
Show moreWe use a spatially explicit biogeochemical end-to-end ecosystem model, Atlantis, to simulate impacts from the Deepwater Horizon oil spill and subsequent recovery of fish guilds. Dose-response relationships with expected oil concentrations were utilized to estimate the impact on fish growth and mortality rates. We also examine the effects of fisheries closures and impacts on recruitment. We validate predictions of the model by comparing population trends and age structure before and after the oil spill with fisheries independent data. The model suggests that recruitment effects and fishery closures had little influence on biomass dynamics. However, at the assumed level of oil concentrations and toxicity, impacts on fish mortality and growth rates were large and commensurate with observations. Sensitivity analysis suggests the biomass of large reef fish decreased by 25% to 50% in areas most affected by the spill, and biomass of large demersal fish decreased even more, by 40% to 70%. Impacts on reef and demersal forage caused starvation mortality in predators and increased reliance on pelagic forage. Impacts on the food web translated effects of the spill far away from the oiled area. Effects on age structure suggest possible delayed impacts on fishery yields. Recovery of high-turnover populations generally is predicted to occur within 10 years, but some slower-growing populations may take 30+ years to fully recover.
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Date Issued: 2018-01-25
Identifier: FSU_pmch_29370187, 10.1371/journal.pone.0190840, PMC5784916, 29370187, 29370187, PONE-D-17-15401
Format: Citation

Title: Synchrotron-generated microbeams induce hippocampal transections in rats.
Creator: Fardone, Erminia, Pouyatos, Benoît, Bräuer-Krisch, Elke, Bartzsch, Stefan, Mathieu, Hervè, Requardt, Herwig, Bucci, Domenico, Barbone, Giacomo, Coan, Paola, Battaglia, Giuseppe,...
Show moreFardone, Erminia, Pouyatos, Benoît, Bräuer-Krisch, Elke, Bartzsch, Stefan, Mathieu, Hervè, Requardt, Herwig, Bucci, Domenico, Barbone, Giacomo, Coan, Paola, Battaglia, Giuseppe, Le Duc, Geraldine, Bravin, Alberto, Romanelli, Pantaleo
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Abstract/Description: Synchrotron-generated microplanar beams (microbeams) provide the most stereo-selective irradiation modality known today. This novel irradiation modality has been shown to control seizures originating from eloquent cortex causing no neurological deficit in experimental animals. To test the hypothesis that application of microbeams in the hippocampus, the most common source of refractory seizures, is safe and does not induce severe side effects, we used microbeams to induce transections to the...
Show moreSynchrotron-generated microplanar beams (microbeams) provide the most stereo-selective irradiation modality known today. This novel irradiation modality has been shown to control seizures originating from eloquent cortex causing no neurological deficit in experimental animals. To test the hypothesis that application of microbeams in the hippocampus, the most common source of refractory seizures, is safe and does not induce severe side effects, we used microbeams to induce transections to the hippocampus of healthy rats. An array of parallel microbeams carrying an incident dose of 600 Gy was delivered to the rat hippocampus. Immunohistochemistry of phosphorylated γ-H2AX showed cell death along the microbeam irradiation paths in rats 48 hours after irradiation. No evident behavioral or neurological deficits were observed during the 3-month period of observation. MR imaging showed no signs of radio-induced edema or radionecrosis 3 months after irradiation. Histological analysis showed a very well preserved hippocampal cytoarchitecture and confirmed the presence of clear-cut microscopic transections across the hippocampus. These data support the use of synchrotron-generated microbeams as a novel tool to slice the hippocampus of living rats in a minimally invasive way, providing (i) a novel experimental model to study hippocampal function and (ii) a new treatment tool for patients affected by refractory epilepsy induced by mesial temporal sclerosis.
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Date Issued: 2018-01-09
Identifier: FSU_pmch_29317649, 10.1038/s41598-017-18000-x, PMC5760574, 29317649, 29317649, 10.1038/s41598-017-18000-x
Format: Citation

Title: Coupling between myosin head conformation and the thick filament backbone structure.
Creator: Hu, Zhongjun, Taylor, Dianne W, Edwards, Robert J, Taylor, Kenneth A
Abstract/Description: The recent high-resolution structure of the thick filament from Lethocerus asynchronous flight muscle shows aspects of thick filament structure never before revealed that may shed some light on how striated muscles function. The phenomenon of stretch activation underlies the function of asynchronous flight muscle. It is most highly developed in flight muscle, but is also observed in other striated muscles such as cardiac muscle. Although stretch activation is likely to be complex, involving...
Show moreThe recent high-resolution structure of the thick filament from Lethocerus asynchronous flight muscle shows aspects of thick filament structure never before revealed that may shed some light on how striated muscles function. The phenomenon of stretch activation underlies the function of asynchronous flight muscle. It is most highly developed in flight muscle, but is also observed in other striated muscles such as cardiac muscle. Although stretch activation is likely to be complex, involving more than a single structural aspect of striated muscle, the thick filament itself, would be a prime site for regulatory function because it must bear all of the tension produced by both its associated myosin motors and any externally applied force. Here we show the first structural evidence that the arrangement of myosin heads within the interacting heads motif is coupled to the structure of the thick filament backbone. We find that a change in helical angle of 0.16° disorders the blocked head preferentially within the Lethocerus interacting heads motif. This observation suggests a mechanism for how tension affects the dynamics of the myosin heads leading to a detailed hypothesis for stretch activation and shortening deactivation, in which the blocked head preferentially binds the thin filament followed by the free head when force production occurs.
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Date Issued: 2017-12-01
Identifier: FSU_pmch_28964844, 10.1016/j.jsb.2017.09.009, PMC5733691, 28964844, 28964844, S1047-8477(17)30160-0
Format: Citation

Title: The structure of the actin-smooth muscle myosin motor domain complex in the rigor state.
Creator: Banerjee, Chaity, Hu, Zhongjun, Huang, Zhong, Warrington, J Anthony, Taylor, Dianne W, Trybus, Kathleen M, Lowey, Susan, Taylor, Kenneth A
Abstract/Description: Myosin-based motility utilizes catalysis of ATP to drive the relative sliding of F-actin and myosin. The earliest detailed model based on cryo-electron microscopy (cryoEM) and X-ray crystallography postulated that higher actin affinity and lever arm movement were coupled to closure of a feature of the myosin head dubbed the actin-binding cleft. Several studies since then using crystallography of myosin-V and cryoEM structures of F-actin bound myosin-I, -II and -V have provided details of this...
Show moreMyosin-based motility utilizes catalysis of ATP to drive the relative sliding of F-actin and myosin. The earliest detailed model based on cryo-electron microscopy (cryoEM) and X-ray crystallography postulated that higher actin affinity and lever arm movement were coupled to closure of a feature of the myosin head dubbed the actin-binding cleft. Several studies since then using crystallography of myosin-V and cryoEM structures of F-actin bound myosin-I, -II and -V have provided details of this model. The smooth muscle myosin II interaction with F-actin may differ from those for striated and non-muscle myosin II due in part to different lengths of important surface loops. Here we report a ∼6 Å resolution reconstruction of F-actin decorated with the nucleotide-free recombinant smooth muscle myosin-II motor domain (MD) from images recorded using a direct electron detector. Resolution is highest for F-actin and the actin-myosin interface (3.5-4 Å) and lowest (∼6-7 Å) for those parts of the MD at the highest radius. Atomic models built into the F-actin density are quite comparable to those previously reported for rabbit muscle actin and show density from the bound ADP. The atomic model of the MD, is quite similar to a recently published structure of vertebrate non-muscle myosin II bound to F-actin and a crystal structure of nucleotide free myosin-V. Larger differences are observed when compared to the cryoEM structure of F-actin decorated with rabbit skeletal muscle myosin subfragment 1. The differences suggest less closure of the 50 kDa domain in the actin bound skeletal muscle myosin structure.
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Date Issued: 2017-12-01
Identifier: FSU_pmch_29038012, 10.1016/j.jsb.2017.10.003, PMC5748330, 29038012, 29038012, S1047-8477(17)30171-5
Format: Citation

Title: Vertical organization of the division of labor within nests of the Florida harvester ant, Pogonomyrmex badius.
Creator: Tschinkel, Walter R, Hanley, Nicholas
Abstract/Description: In the Florida harvester ant, Pogonomyrmex badius, foragers occur only in the top 15 cm of the nest, whereas brood and brood-care workers reside mostly in the deepest regions, yet the food and seeds foragers collect must be transported downward 30 to 80 cm to seed chambers and up to 2 m to brood chambers. Using mark-recapture techniques with fluorescent printer's ink, we identified a class of workers that ranges widely within the vertical structure of the nest, rapidly moving materials...
Show moreIn the Florida harvester ant, Pogonomyrmex badius, foragers occur only in the top 15 cm of the nest, whereas brood and brood-care workers reside mostly in the deepest regions, yet the food and seeds foragers collect must be transported downward 30 to 80 cm to seed chambers and up to 2 m to brood chambers. Using mark-recapture techniques with fluorescent printer's ink, we identified a class of workers that ranges widely within the vertical structure of the nest, rapidly moving materials dropped by foragers in the upper regions downward, and excavated soil from deeper upward. Within the nest, only 5% of foragers were recovered below 20 cm depth, but about 30% of transfer workers and 82% of unmarked workers were found there. Below 70 cm depth, 90% of workers were unmarked, and were probably involved mostly in brood care. During the summer, the transfer workers comprise about a quarter of the nest population, while foragers make up about 40%. Workers marked as transfer workers later appear as foragers, while those marked as foragers die and disappear from the foraging population, suggesting that transfer workers are younger, and age into foraging. The importance of these findings for laboratory studies of division of labor are discussed. The efficient allocation of labor is a key component of superorganismal fitness.
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Date Issued: 2017-11-28
Identifier: FSU_pmch_29182686, 10.1371/journal.pone.0188630, PMC5705139, 29182686, 29182686, PONE-D-17-32984
Format: Citation

Title: Stability of Wake-Sleep Cycles Requires Robust Degradation of the PERIOD Protein.
Creator: D'Alessandro, Matthew, Beesley, Stephen, Kim, Jae Kyoung, Jones, Zachary, Chen, Rongmin, Wi, Julie, Kyle, Kathleen, Vera, Daniel, Pagano, Michele, Nowakowski, Richard, Lee, Choogon
Abstract/Description: Robustness in biology is the stability of phenotype under diverse genetic and/or environmental perturbations. The circadian clock has remarkable stability of period and phase that-unlike other biological oscillators-is maintained over a wide range of conditions. Here, we show that the high fidelity of the circadian system stems from robust degradation of the clock protein PERIOD. We show that PERIOD degradation is regulated by a balance between ubiquitination and deubiquitination, and that...
Show moreRobustness in biology is the stability of phenotype under diverse genetic and/or environmental perturbations. The circadian clock has remarkable stability of period and phase that-unlike other biological oscillators-is maintained over a wide range of conditions. Here, we show that the high fidelity of the circadian system stems from robust degradation of the clock protein PERIOD. We show that PERIOD degradation is regulated by a balance between ubiquitination and deubiquitination, and that disruption of this balance can destabilize the clock. In mice with a loss-of-function mutation of the E3 ligase gene β-Trcp2, the balance of PERIOD degradation is perturbed and the clock becomes dramatically unstable, presenting a unique behavioral phenotype unlike other circadian mutant animal models. We believe that our data provide a molecular explanation for how circadian phases, such as wake-sleep onset times, can become unstable in humans, and we present a unique mouse model to study human circadian disorders with unstable circadian rhythm phases.
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Date Issued: 2017-11-20
Identifier: FSU_pmch_29103939, 10.1016/j.cub.2017.10.014, PMC5698108, 29103939, 29103939, S0960-9822(17)31317-9
Format: Citation

Title: Direct detection of neural activity in vitro using magnetic resonance electrical impedance tomography (MREIT).
Creator: Sadleir, Rosalind J, Fu, Fanrui, Falgas, Corey, Holland, Stephen, Boggess, May, Grant, Samuel C, Woo, Eung Je
Abstract/Description: We describe a sequence of experiments performed in vitro to verify the existence of a new magnetic resonance imaging contrast - Magnetic Resonance Electrical Impedance Tomography (MREIT) -sensitive to changes in active membrane conductivity. We compared standard deviations in MREIT phase data from spontaneously active Aplysia abdominal ganglia in an artificial seawater background solution (ASW) with those found after treatment with an excitotoxic solution (KCl). We found significant increases...
Show moreWe describe a sequence of experiments performed in vitro to verify the existence of a new magnetic resonance imaging contrast - Magnetic Resonance Electrical Impedance Tomography (MREIT) -sensitive to changes in active membrane conductivity. We compared standard deviations in MREIT phase data from spontaneously active Aplysia abdominal ganglia in an artificial seawater background solution (ASW) with those found after treatment with an excitotoxic solution (KCl). We found significant increases in MREIT treatment cases, compared to control ganglia subject to extra ASW. This distinction was not found in phase images from the same ganglia using no imaging current. Further, significance and effect size depended on the amplitude of MREIT imaging current used. We conclude that our observations were linked to changes in cell conductivity caused by activity. Functional MREIT may have promise as a more direct method of functional neuroimaging than existing methods that image correlates of blood flow such as BOLD fMRI.
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Date Issued: 2017-11-01
Identifier: FSU_pmch_28818695, 10.1016/j.neuroimage.2017.08.004, PMC5696120, 28818695, 28818695, S1053-8119(17)30651-1
Format: Citation

Title: Neuronal Intrinsic Physiology Changes During Development of a Learned Behavior.
Creator: Ross, Matthew T, Flores, Diana, Bertram, Richard, Johnson, Frank, Hyson, Richard L
Abstract/Description: Juvenile male zebra finches learn their songs over distinct auditory and sensorimotor stages, the former requiring exposure to an adult tutor song pattern. The cortical premotor nucleus HVC (acronym is name) plays a necessary role in both learning stages, as well as the production of adult song. Consistent with neural network models where synaptic plasticity mediates developmental forms of learning, exposure to tutor song drives changes in the turnover, density, and morphology of HVC synapses...
Show moreJuvenile male zebra finches learn their songs over distinct auditory and sensorimotor stages, the former requiring exposure to an adult tutor song pattern. The cortical premotor nucleus HVC (acronym is name) plays a necessary role in both learning stages, as well as the production of adult song. Consistent with neural network models where synaptic plasticity mediates developmental forms of learning, exposure to tutor song drives changes in the turnover, density, and morphology of HVC synapses during vocal development. A network's output, however, is also influenced by the intrinsic properties (e.g., ion channels) of the component neurons, which could change over development. Here, we use patch clamp recordings to show cell-type-specific changes in the intrinsic physiology of HVC projection neurons as a function of vocal development. Developmental changes in HVC neurons that project to the basal ganglia include an increased voltage sag response to hyperpolarizing currents and an increased rebound depolarization following hyperpolarization. Developmental changes in HVC neurons that project to vocal-motor cortex include a decreased resting membrane potential and an increased spike amplitude. HVC interneurons, however, show a relatively stable range of intrinsic features across vocal development. We used mathematical models to deduce possible changes in ionic currents that underlie the physiological changes and to show that the magnitude of the observed changes could alter HVC circuit function. The results demonstrate developmental plasticity in the intrinsic physiology of HVC projection neurons and suggest that intrinsic plasticity may have a role in the process of song learning.
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Date Issued: 2017-10-20
Identifier: FSU_pmch_29062887, 10.1523/ENEURO.0297-17.2017, PMC5649544, 29062887, 29062887, eN-NWR-0297-17
Format: Citation

Title: Metabolic Support of Excised, Living Brain Tissues During Magnetic Resonance Microscopy Acquisition.
Creator: Flint, Jeremy J, Menon, Kannan, Hansen, Brian, Forder, John, Blackband, Stephen J
Abstract/Description: This protocol describes the procedures necessary to support normal metabolic functions of acute brain slice preparations during the collection of magnetic resonance (MR) microscopy data. While it is possible to perform MR collections on living, excised mammalian tissue, such experiments have traditionally been constrained by resolution limits and are thus incapable of visualizing tissue microstructure. Conversely, MR protocols that did achieve microscopic image resolution required the use of...
Show moreThis protocol describes the procedures necessary to support normal metabolic functions of acute brain slice preparations during the collection of magnetic resonance (MR) microscopy data. While it is possible to perform MR collections on living, excised mammalian tissue, such experiments have traditionally been constrained by resolution limits and are thus incapable of visualizing tissue microstructure. Conversely, MR protocols that did achieve microscopic image resolution required the use of fixed samples to accommodate the need for static, unchanging conditions over lengthy scan times. The current protocol describes the first available MR technique that enables imaging of living, mammalian tissue samples at microscopic resolutions. Such data is of great importance to the understanding of how pathology-based contrast changes occurring at the microscopic level influence the content of macroscopic MR scans such as those used in the clinic. Once such an understanding is realized, diagnostic methods with greater sensitivity and accuracy can be developed, which will translate directly to earlier disease treatment, more accurate therapy monitoring and improved patient outcomes. While the described methodology focuses on brain slice preparations, the protocol is adaptable to any excised tissue slice given that changes are made to the gas and perfusate preparations to accommodate the tissue's specific metabolic needs. Successful execution of the protocol should result in living, acute slice preparations that exhibit MR diffusion signal stability for periods up to 15.5 h. The primary advantages of the current system over other MR compatible perfusion apparatuses are its compatibility with the MR microscopy hardware required to attain higher resolution images and ability to provide constant, uninterrupted flow with carefully regulated perfusate conditions. Reduced sample throughput is a consideration with this design as only one tissue slice may be imaged at a time.
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Date Issued: 2017-10-18
Identifier: FSU_pmch_29155793, 10.3791/56282, PMC5752427, 29155793, 29155793
Format: Citation

Title: 3'-UTR and microRNA-24 regulate circadian rhythms by repressing PERIOD2 protein accumulation.
Creator: Yoo, Seung-Hee, Kojima, Shihoko, Shimomura, Kazuhiro, Koike, Nobuya, Buhr, Ethan D, Furukawa, Tadashi, Ko, Caroline H, Gloston, Gabrielle, Ayoub, Christopher, Nohara, Kazunari,...
Show moreYoo, Seung-Hee, Kojima, Shihoko, Shimomura, Kazuhiro, Koike, Nobuya, Buhr, Ethan D, Furukawa, Tadashi, Ko, Caroline H, Gloston, Gabrielle, Ayoub, Christopher, Nohara, Kazunari, Reyes, Bryan A, Tsuchiya, Yoshiki, Yoo, Ook-Joon, Yagita, Kazuhiro, Lee, Choogon, Chen, Zheng, Yamazaki, Shin, Green, Carla B, Takahashi, Joseph S
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Abstract/Description: We previously created two PER2::LUCIFERASE (PER2::LUC) circadian reporter knockin mice that differ only in the 3'-UTR region: , which retains the endogenous 3'-UTR and , where the endogenous 3'-UTR was replaced by an SV40 late poly(A) signal. To delineate the in vivo functions of 3'-UTR, we analyzed circadian rhythms of mice. Interestingly, mice displayed more than threefold stronger amplitude in bioluminescence rhythms than mice, and also exhibited lengthened free-running periods (∼24.0 h),...
Show moreWe previously created two PER2::LUCIFERASE (PER2::LUC) circadian reporter knockin mice that differ only in the 3'-UTR region: , which retains the endogenous 3'-UTR and , where the endogenous 3'-UTR was replaced by an SV40 late poly(A) signal. To delineate the in vivo functions of 3'-UTR, we analyzed circadian rhythms of mice. Interestingly, mice displayed more than threefold stronger amplitude in bioluminescence rhythms than mice, and also exhibited lengthened free-running periods (∼24.0 h), greater phase delays following light pulse, and enhanced temperature compensation relative to Analysis of the 3'-UTR sequence revealed that miR-24, and to a lesser degree miR-30, suppressed PER2 protein translation, and the reversal of this inhibition in augmented PER2::LUC protein level and oscillatory amplitude. Interestingly, mRNA and protein oscillatory amplitude as well as CRY1 protein oscillation were increased in mice, suggesting rhythmic overexpression of PER2 enhances expression of and other core clock genes. Together, these studies provide important mechanistic insights into the regulatory roles of 3'-UTR, miR-24, and PER2 in expression and core clock function.
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Date Issued: 2017-10-17
Identifier: FSU_pmch_28973913, 10.1073/pnas.1706611114, PMC5651750, 28973913, 28973913, 1706611114
Format: Citation

Title: Proteomic analyses of nucleus laminaris identified candidate targets of the fragile X mental retardation protein.
Creator: Sakano, Hitomi, Zorio, Diego A R, Wang, Xiaoyu, Ting, Ying S, Noble, William S, MacCoss, Michael J, Rubel, Edwin W, Wang, Yuan
Abstract/Description: The avian nucleus laminaris (NL) is a brainstem nucleus necessary for binaural processing, analogous in structure and function to the mammalian medial superior olive. In chickens (Gallus gallus), NL is a well-studied model system for activity-dependent neural plasticity. Its neurons have bipolar extension of dendrites, which receive segregated inputs from two ears and display rapid and compartment-specific reorganization in response to unilateral changes in auditory input. More recently,...
Show moreThe avian nucleus laminaris (NL) is a brainstem nucleus necessary for binaural processing, analogous in structure and function to the mammalian medial superior olive. In chickens (Gallus gallus), NL is a well-studied model system for activity-dependent neural plasticity. Its neurons have bipolar extension of dendrites, which receive segregated inputs from two ears and display rapid and compartment-specific reorganization in response to unilateral changes in auditory input. More recently, fragile X mental retardation protein (FMRP), an RNA-binding protein that regulates local protein translation, has been shown to be enriched in NL dendrites, suggesting its potential role in the structural dynamics of these dendrites. To explore the molecular role of FMRP in this nucleus, we performed proteomic analysis of NL, using micro laser capture and liquid chromatography tandem mass spectrometry. We identified 657 proteins, greatly represented in pathways involved in mitochondria, translation and metabolism, consistent with high levels of activity of NL neurons. Of these, 94 are potential FMRP targets, by comparative analysis with previously proposed FMRP targets in mammals. These proteins are enriched in pathways involved in cellular growth, cellular trafficking and transmembrane transport. Immunocytochemistry verified the dendritic localization of several proteins in NL. Furthermore, we confirmed the direct interaction of FMRP with one candidate, RhoC, by in vitro RNA binding assays. In summary, we provide a database of highly expressed proteins in NL and in particular a list of potential FMRP targets, with the goal of facilitating molecular characterization of FMRP signaling in future studies.
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Date Issued: 2017-10-15
Identifier: FSU_pmch_28685837, 10.1002/cne.24281, PMC5564178, 28685837, 28685837
Format: Citation

Title: Aging and circadian dysfunction increase alcohol sensitivity and exacerbate mortality in Drosophila melanogaster.
Creator: De Nobrega, Aliza K, Mellers, Alana P, Lyons, Lisa C
Abstract/Description: Alcohol abuse is a rising problem in middle-aged and older individuals resulting in serious health, family and economic consequences. Effective treatment necessitates the identification of factors influencing alcohol toxicity with aging. We investigated the interaction between aging, alcohol toxicity and circadian function using Drosophila as a model system. We found as wild type flies age, sensitivity to alcohol increases and circadian regulation of alcohol-induced behaviors weakens....
Show moreAlcohol abuse is a rising problem in middle-aged and older individuals resulting in serious health, family and economic consequences. Effective treatment necessitates the identification of factors influencing alcohol toxicity with aging. We investigated the interaction between aging, alcohol toxicity and circadian function using Drosophila as a model system. We found as wild type flies age, sensitivity to alcohol increases and circadian regulation of alcohol-induced behaviors weakens. Decreased circadian modulation is correlated with significantly greater alcohol sensitivity during the subjective day. The circadian clock modulates alcohol-induced mortality in younger flies with increased mortality following alcohol exposure at night. Older flies exhibit significantly longer recovery times following alcohol-induced sedation and increased mortality following binge-like or chronic alcohol exposure. Flies rendered arrhythmic either genetically or environmentally exhibit significantly increased alcohol sensitivity, longer recovery times and increased mortality. We hypothesize that the circadian clock phase specifically buffers behavioral and cellular alcohol sensitivity with this protection diminishing as the circadian clock weakens with age.
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Date Issued: 2017-10-15
Identifier: FSU_pmch_28750752, 10.1016/j.exger.2017.07.014, PMC6158789, 28750752, 28750752, S0531-5565(17)30055-4
Format: Citation

Title: The Hox proteins Ubx and AbdA collaborate with the transcription pausing factor M1BP to regulate gene transcription.
Creator: Zouaz, Amel, Auradkar, Ankush, Delfini, Marie Claire, Macchi, Meiggie, Barthez, Marine, Ela Akoa, Serge, Bastianelli, Leila, Xie, Gengqiang, Deng, Wu-Min, Levine, Stuart S,...
Show moreZouaz, Amel, Auradkar, Ankush, Delfini, Marie Claire, Macchi, Meiggie, Barthez, Marine, Ela Akoa, Serge, Bastianelli, Leila, Xie, Gengqiang, Deng, Wu-Min, Levine, Stuart S, Graba, Yacine, Saurin, Andrew J
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Abstract/Description: In metazoans, the pausing of RNA polymerase II at the promoter (paused Pol II) has emerged as a widespread and conserved mechanism in the regulation of gene transcription. While critical in recruiting Pol II to the promoter, the role transcription factors play in transitioning paused Pol II into productive Pol II is, however, little known. By studying how Hox transcription factors control transcription, we uncovered a molecular mechanism that increases productive transcription. We found that...
Show moreIn metazoans, the pausing of RNA polymerase II at the promoter (paused Pol II) has emerged as a widespread and conserved mechanism in the regulation of gene transcription. While critical in recruiting Pol II to the promoter, the role transcription factors play in transitioning paused Pol II into productive Pol II is, however, little known. By studying how Hox transcription factors control transcription, we uncovered a molecular mechanism that increases productive transcription. We found that the Hox proteins AbdA and Ubx target gene promoters previously bound by the transcription pausing factor M1BP, containing paused Pol II and enriched with promoter-proximal Polycomb Group (PcG) proteins, yet lacking the classical H3K27me3 PcG signature. We found that AbdA binding to M1BP-regulated genes results in reduction in PcG binding, the release of paused Pol II, increases in promoter H3K4me3 histone marks and increased gene transcription. Linking transcription factors, PcG proteins and paused Pol II states, these data identify a two-step mechanism of Hox-driven transcription, with M1BP binding leading to Pol II recruitment followed by AbdA targeting, which results in a change in the chromatin landscape and enhanced transcription.
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Date Issued: 2017-10-02
Identifier: FSU_pmch_28871058, 10.15252/embj.201695751, PMC5623858, 28871058, 28871058, embj.201695751
Format: Citation

Title: Heterogeneous organization and connectivity of the chicken auditory thalamus (Gallus gallus).
Creator: Wang, Yuan, Zorio, Diego A R, Karten, Harvey J
Abstract/Description: The auditory ascending system contains parallel pathways in vertebrate brains. In chickens (Gallus gallus), three pathways arise from nucleus laminaris (NL), nucleus angularis (NA), and regio intermedius (RI) in the brainstem, innervating three subdivisions of the nucleus mesencephalicus lateralis pars dorsalis (MLd) in the midbrain. The current study reveals the segregation of these pathways in their subsequent projections to the nucleus ovoidalis (Ov) in the thalamus. Based on...
Show moreThe auditory ascending system contains parallel pathways in vertebrate brains. In chickens (Gallus gallus), three pathways arise from nucleus laminaris (NL), nucleus angularis (NA), and regio intermedius (RI) in the brainstem, innervating three subdivisions of the nucleus mesencephalicus lateralis pars dorsalis (MLd) in the midbrain. The current study reveals the segregation of these pathways in their subsequent projections to the nucleus ovoidalis (Ov) in the thalamus. Based on cytoarchitecture and myelin distribution, we identified seven Ov subregions, including five neuronal clusters within the Ov proper, the nucleus semilunaris parovoidalis (SPO), and the circum-ovoidalis (cOv). Immunocytochemistry further revealed that a ventromedial cluster of the Ov proper (Ovvm) contains unique cell types expressing α8 subunit nicotinic acetylcholine receptor, while SPO and cOv are characterized with expression of calcitonin-gene-related peptide and cholecystokinin. Tract tracing studies demonstrated that Ovvm is a major target of the NL-recipient zone of MLd, while the RI-recipient zone of MLd predominantly projects to a ventrolateral cluster of the Ov proper. Afferent inputs to the remaining regions of the Ov proper mostly arise from the NA-recipient zone of MLd. SPO and cOv receive a projection from the surrounding areas of MLd, named the nucleus intercollicularis. Importantly, the Ov proper, SPO and cOv all project to the Field L2 in the forebrain, the avian auditory cortex. Taken together, these results demonstrate that the avian auditory thalamus is a structurally and functionally heterogeneous structure, implicating an important role in generating novel representations for specific acoustic features.
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Date Issued: 2017-10-01
Identifier: FSU_pmch_28614906, 10.1002/cne.24262, PMC5558206, 28614906, 28614906
Format: Citation

Title: Thirst Increases Chorda Tympani Responses to Sodium Chloride.
Creator: Mast, Thomas G, Breza, Joseph M, Contreras, Robert J
Abstract/Description: In nature, water is present as a low-salt solution, thus we hypothesized that thirst would increase taste responses to low-salt solutions. We investigated the effect of thirst on the 2 different salt detection mechanisms present in the rat chorda tympani (CT) nerve. The first mechanism is dependent upon the epithelial sodium channel (ENaC), is blocked by benzamil, and is specific to the cation sodium. The second mechanism, while undefined, is independent of ENaC, and detects multiple cations....
Show moreIn nature, water is present as a low-salt solution, thus we hypothesized that thirst would increase taste responses to low-salt solutions. We investigated the effect of thirst on the 2 different salt detection mechanisms present in the rat chorda tympani (CT) nerve. The first mechanism is dependent upon the epithelial sodium channel (ENaC), is blocked by benzamil, and is specific to the cation sodium. The second mechanism, while undefined, is independent of ENaC, and detects multiple cations. We expected thirst to increase benzamil-sensitive sodium responses due to mechanistically increasing the benzamil-sensitive ENaC. We recorded CT whole-nerve electrophysiological responses to lingual application of NaCl, KCl (30, 75, 150, 300, 500, and 600 mM), and imitation rainwater in both control and 24-h water-restricted male rats. NaCl solutions were presented in artificial saliva before and after lingual application of 5µM benzamil. Water restriction significantly increased the integrated CT responses to NaCl but not to KCl or imitation rainwater. Consistent with our hypothesis, only the benzamil-sensitive, and not the benzamil-insensitive, CT sodium response significantly increased. Additionally, CT responses to salt were recorded following induction of either osmotic or volemic thirst. Both thirsts significantly enhanced the integrated CT responses to NaCl and KCl, but not imitation rainwater. Interestingly, osmotic and volemic thirsts increased CT responses by increasing both the benzamil-sensitive and benzamil-insensitive CT sodium responses. We propose that thirst increases the sensitivity of the CT nerve to sodium.
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Date Issued: 2017-10-01
Identifier: FSU_pmch_28981824, 10.1093/chemse/bjx052, PMC5863560, 28981824, 28981824, 4083245
Format: Citation

Title: Effects of pair bonding on parental behavior and dopamine activity in the nucleus accumbens in male prairie voles.
Creator: Lei, K, Liu, Y, Smith, A S, Lonstein, J S, Wang, Z
Abstract/Description: Male parental care is a vital behavior for the development as well as the physical and mental well-being of the young. However, little is known about the neurochemical regulation of male parental behavior, mainly due to the lack of appropriate animal models. In this study, we used the socially monogamous male prairie vole (Microtus ochrogaster) to investigate the effect of pair-bonding experience on paternal behavior and dopamine (DA) signaling in the nucleus accumbens (NAcc) in the brain. We...
Show moreMale parental care is a vital behavior for the development as well as the physical and mental well-being of the young. However, little is known about the neurochemical regulation of male parental behavior, mainly due to the lack of appropriate animal models. In this study, we used the socially monogamous male prairie vole (Microtus ochrogaster) to investigate the effect of pair-bonding experience on paternal behavior and dopamine (DA) signaling in the nucleus accumbens (NAcc) in the brain. We compared sexually naïve males with males that were pair bonded with a female for two weeks. Our data showed that pair-bonded males displayed enhanced paternal behavior, particularly in pup licking/grooming, associated with increased DA type-1 receptor (D1R) protein expression in the NAcc, compared to sexually naïve males. Site-specific brain microdialysis revealed a significant, but transient, increase in DA release in the NAcc associated with pup exposure in both groups of the males. Further, pharmacological blockade of D1R in the NAcc decreased pup licking/grooming in the pair-bonded males. Together, our data demonstrate that pair-bonding experience with a female facilitated male parental behavior via NAcc D1R mediation in male prairie voles.
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Date Issued: 2017-10-01
Identifier: FSU_pmch_28858415, 10.1111/ejn.13673, PMC5624856, 28858415, 28858415
Format: Citation

Title: Smart thermosensitive liposomes for effective solid tumor therapy and in vivo imaging.
Creator: Affram, Kevin, Udofot, Ofonime, Singh, Mandip, Krishnan, Sunil, Reams, Renee, Rosenberg, Jens, Agyare, Edward
Abstract/Description: In numerous studies, liposomes have been used to deliver anticancer drugs such as doxorubicin to local heat-triggered tumor. Here, we investigate: (i) the ability of thermosensitive liposomal nanoparticle (TSLnp) as a delivery system to deliver poorly membrane-permeable anticancer drug, gemcitabine (Gem) to solid pancreatic tumor with the aid of local mild hyperthermia and, (ii) the possibility of using gadolinium (Magnevist®) loaded-TSLnps (Gd-TSLnps) to increase magnetic resonance imaging ...
Show moreIn numerous studies, liposomes have been used to deliver anticancer drugs such as doxorubicin to local heat-triggered tumor. Here, we investigate: (i) the ability of thermosensitive liposomal nanoparticle (TSLnp) as a delivery system to deliver poorly membrane-permeable anticancer drug, gemcitabine (Gem) to solid pancreatic tumor with the aid of local mild hyperthermia and, (ii) the possibility of using gadolinium (Magnevist®) loaded-TSLnps (Gd-TSLnps) to increase magnetic resonance imaging (MRI) contrast in solid tumor. In this study, we developed and tested gemcitabine-loaded thermosensitive liposomal nanoparticles (Gem-TSLnps) and gadolinium-loaded thermosensitive liposomal nanoparticles (Gd-TSLnps) both in in-vitro and in-vivo. The TSLnps exhibited temperature-dependent release of Gem, at 40-42°C, 65% of Gem was released within 10 min, whereas < 23% Gem leakage occurred at 37°C after a period of 2 h. The pharmacokinetic parameters and tissue distribution of both Gem-TSLnps and Gd-TSLnps were significantly greater compared with free Gem and Gd, while Gem-TSLnps plasma clearance was reduced by 17-fold and that of Gd-TSLpns was decreased by 2-fold. Area under the plasma concentration time curve (AUC) of Gem-TSLnps (35.17± 0.04 μghr/mL) was significantly higher than that of free Gem (2.09 ± 0.01 μghr/mL) whereas, AUC of Gd-TSLnps was higher than free Gd by 3.9 fold high. TSLnps showed significant Gem accumulation in heated tumor relative to free Gem. Similar trend of increased Gd-TSLnps accumulation was observed in non-heated tumor compared to that of free Gd; however, no significant difference in MRI contrast enhancement between free Gd and Gd-TSLnps ex-vivo tumor images was observed. Despite Gem-TSLnps dose being half of free Gem dose, antitumor efficacy of Gem-TSLnps was comparable to that of free Gem(Gem-TSLnps 10 mg Gem/kg compared with free Gem 20 mg/kg). Overall, the findings suggest that TSLnps may be used to improve Gem delivery and enhance its antitumor activity. However, the formulation of Gd-TSLnp needs to be fully optimized to significantly enhance MRI contrast in tumor.
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Date Issued: 2017-09-21
Identifier: FSU_pmch_28934281, 10.1371/journal.pone.0185116, PMC5608370, 28934281, 28934281, PONE-D-17-14628
Format: Citation

Title: Laminar Organization of Encoding and Memory Reactivation in the Parietal Cortex.
Creator: Wilber, Aaron A, Skelin, Ivan, Wu, Wei, McNaughton, Bruce L
Abstract/Description: Egocentric neural coding has been observed in parietal cortex (PC), but its topographical and laminar organization is not well characterized. We used multi-site recording to look for evidence of local clustering and laminar consistency of linear and angular velocity encoding in multi-neuronal spiking activity (MUA) and in the high-frequency (300-900 Hz) component of the local field potential (HF-LFP), believed to reflect local spiking activity. Rats were trained to run many trials on a large...
Show moreEgocentric neural coding has been observed in parietal cortex (PC), but its topographical and laminar organization is not well characterized. We used multi-site recording to look for evidence of local clustering and laminar consistency of linear and angular velocity encoding in multi-neuronal spiking activity (MUA) and in the high-frequency (300-900 Hz) component of the local field potential (HF-LFP), believed to reflect local spiking activity. Rats were trained to run many trials on a large circular platform, either to LED-cued goal locations or as a spatial sequence from memory. Tuning to specific self-motion states was observed and exhibited distinct cortical depth-invariant coding properties. These patterns of collective local and laminar activation during behavior were reactivated in compressed form during post-experience sleep and temporally coupled to cortical delta waves and hippocampal sharp-wave ripples. Thus, PC neuron motion encoding is consistent across cortical laminae, and this consistency is maintained during memory reactivation.
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Date Issued: 2017-09-13
Identifier: FSU_pmch_28910623, 10.1016/j.neuron.2017.08.033, PMC5679317, 28910623, 28910623, S0896-6273(17)30748-1
Format: Citation

Title: Zika-Virus-Encoded NS2A Disrupts Mammalian Cortical Neurogenesis by Degrading Adherens Junction Proteins.
Creator: Yoon, Ki-Jun, Song, Guang, Qian, Xuyu, Pan, Jianbo, Xu, Dan, Rho, Hee-Sool, Kim, Nam-Shik, Habela, Christa, Zheng, Lily, Jacob, Fadi, Zhang, Feiran, Lee, Emily M, Huang, Wei-Kai...
Show moreYoon, Ki-Jun, Song, Guang, Qian, Xuyu, Pan, Jianbo, Xu, Dan, Rho, Hee-Sool, Kim, Nam-Shik, Habela, Christa, Zheng, Lily, Jacob, Fadi, Zhang, Feiran, Lee, Emily M, Huang, Wei-Kai, Ringeling, Francisca Rojas, Vissers, Caroline, Li, Cui, Yuan, Ling, Kang, Koeun, Kim, Sunghan, Yeo, Junghoon, Cheng, Yichen, Liu, Sheng, Wen, Zhexing, Qin, Cheng-Feng, Wu, Qingfeng, Christian, Kimberly M, Tang, Hengli, Jin, Peng, Xu, Zhiheng, Qian, Jiang, Zhu, Heng, Song, Hongjun, Ming, Guo-Li
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Abstract/Description: Zika virus (ZIKV) directly infects neural progenitors and impairs their proliferation. How ZIKV interacts with the host molecular machinery to impact neurogenesis in vivo is not well understood. Here, by systematically introducing individual proteins encoded by ZIKV into the embryonic mouse cortex, we show that expression of ZIKV-NS2A, but not Dengue virus (DENV)-NS2A, leads to reduced proliferation and premature differentiation of radial glial cells and aberrant positioning of newborn...
Show moreZika virus (ZIKV) directly infects neural progenitors and impairs their proliferation. How ZIKV interacts with the host molecular machinery to impact neurogenesis in vivo is not well understood. Here, by systematically introducing individual proteins encoded by ZIKV into the embryonic mouse cortex, we show that expression of ZIKV-NS2A, but not Dengue virus (DENV)-NS2A, leads to reduced proliferation and premature differentiation of radial glial cells and aberrant positioning of newborn neurons. Mechanistically, in vitro mapping of protein-interactomes and biochemical analysis suggest interactions between ZIKA-NS2A and multiple adherens junction complex (AJ) components. Functionally, ZIKV-NS2A, but not DENV-NS2A, destabilizes the AJ complex, resulting in impaired AJ formation and aberrant radial glial fiber scaffolding in the embryonic mouse cortex. Similarly, ZIKA-NS2A, but not DENV-NS2A, reduces radial glial cell proliferation and causes AJ deficits in human forebrain organoids. Together, our results reveal pathogenic mechanisms underlying ZIKV infection in the developing mammalian brain.
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Date Issued: 2017-09-07
Identifier: FSU_pmch_28826723, 10.1016/j.stem.2017.07.014, PMC5600197, 28826723, 28826723, S1934-5909(17)30293-X
Format: Citation

Title: Zika virus directly infects peripheral neurons and induces cell death.
Creator: Oh, Yohan, Zhang, Feiran, Wang, Yaqing, Lee, Emily M, Choi, In Young, Lim, Hotae, Mirakhori, Fahimeh, Li, Ronghua, Huang, Luoxiu, Xu, Tianlei, Wu, Hao, Li, Cui, Qin, Cheng-Feng,...
Show moreOh, Yohan, Zhang, Feiran, Wang, Yaqing, Lee, Emily M, Choi, In Young, Lim, Hotae, Mirakhori, Fahimeh, Li, Ronghua, Huang, Luoxiu, Xu, Tianlei, Wu, Hao, Li, Cui, Qin, Cheng-Feng, Wen, Zhexing, Wu, Qing-Feng, Tang, Hengli, Xu, Zhiheng, Jin, Peng, Song, Hongjun, Ming, Guo-Li, Lee, Gabsang
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Abstract/Description: Zika virus (ZIKV) infection is associated with neurological disorders of both the CNS and peripheral nervous systems (PNS), yet few studies have directly examined PNS infection. Here we show that intraperitoneally or intraventricularly injected ZIKV in the mouse can infect and impact peripheral neurons in vivo. Moreover, ZIKV productively infects stem-cell-derived human neural crest cells and peripheral neurons in vitro, leading to increased cell death, transcriptional dysregulation and cell...
Show moreZika virus (ZIKV) infection is associated with neurological disorders of both the CNS and peripheral nervous systems (PNS), yet few studies have directly examined PNS infection. Here we show that intraperitoneally or intraventricularly injected ZIKV in the mouse can infect and impact peripheral neurons in vivo. Moreover, ZIKV productively infects stem-cell-derived human neural crest cells and peripheral neurons in vitro, leading to increased cell death, transcriptional dysregulation and cell-type-specific molecular pathology.
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Date Issued: 2017-09-01
Identifier: FSU_pmch_28758997, 10.1038/nn.4612, PMC5575960, 28758997, 28758997, nn.4612
Format: Citation

Title: Muroid rodent phylogenetics: 900-species tree reveals increasing diversification rates..
Creator: Steppan, Scott J, Schenk, John J
Abstract/Description: We combined new sequence data for more than 300 muroid rodent species with our previously published sequences for up to five nuclear and one mitochondrial genes to generate the most widely and densely sampled hypothesis of evolutionary relationships across Muroidea. An exhaustive screening procedure for publically available sequences was implemented to avoid the propagation of taxonomic errors that are common to supermatrix studies. The combined data set of carefully screened sequences...
Show moreWe combined new sequence data for more than 300 muroid rodent species with our previously published sequences for up to five nuclear and one mitochondrial genes to generate the most widely and densely sampled hypothesis of evolutionary relationships across Muroidea. An exhaustive screening procedure for publically available sequences was implemented to avoid the propagation of taxonomic errors that are common to supermatrix studies. The combined data set of carefully screened sequences derived from all available sequences on GenBank with our new data resulted in a robust maximum likelihood phylogeny for 900 of the approximately 1,620 muroids. Several regions that were equivocally resolved in previous studies are now more decisively resolved, and we estimated a chronogram using 28 fossil calibrations for the most integrated age and topological estimates to date. The results were used to update muroid classification and highlight questions needing additional data. We also compared the results of multigene supermatrix studies like this one with the principal published supertrees and concluded that the latter are unreliable for any comparative study in muroids. In addition, we explored diversification patterns as an explanation for why muroid rodents represent one of the most species-rich groups of mammals by detecting evidence for increasing net diversification rates through time across the muroid tree. We suggest the observation of increasing rates may be due to a combination of parallel increases in rate across clades and high average extinction rates. Five increased diversification-rate-shifts were inferred, suggesting that multiple, but perhaps not independent, events have led to the remarkable species diversity in the superfamily. Our results provide a phylogenetic framework for comparative studies that is not highly dependent upon the signal from any one gene.
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Date Issued: 2017-08-16
Identifier: FSU_pmch_28813483, 10.1371/journal.pone.0183070, PMC5559066, 28813483, 28813483, PONE-D-16-50122
Format: Citation

Title: Identification of a common Ara h 3 epitope recognized by both the capture and the detection monoclonal antibodies in an ELISA detection kit.
Creator: Zhao, Lipei, Zhao, Liang, Zhang, Buchang, Robotham, Jason M, Roux, Kenneth H, Tang, Hengli
Abstract/Description: Allergy to peanuts has become a common and severe problem, especially in westernized countries. In this study, we evaluated the target and epitope specificity of the capture and detection mouse monoclonal antibodies (mAbs) used in a commercial peanut allergen detection platform. We first identified the target of these antibodies as Ara h 3 and then used an overlapping peptide array of Ara h 3 to determine the antibody-binding epitopes. Further amino acids critical for the binding via alanine...
Show moreAllergy to peanuts has become a common and severe problem, especially in westernized countries. In this study, we evaluated the target and epitope specificity of the capture and detection mouse monoclonal antibodies (mAbs) used in a commercial peanut allergen detection platform. We first identified the target of these antibodies as Ara h 3 and then used an overlapping peptide array of Ara h 3 to determine the antibody-binding epitopes. Further amino acids critical for the binding via alanine substitutions at individual amino acid residues within the epitope were mapped. Finally, inhibition ELISA and inhibition immunoblotting using a recombinant Ara h 3 protein were performed to confirm these results. Surprisingly, the capture and detection mAbs showed identical binding characteristics and were presumed to represent two isolates of the same clone, a notion supported by both isoelectric focusing electrophoresis and Liquid chromatography-mass spectrometry experiments. The simultaneous binding of a pair of identical mAbs to an individual allergen such as Ara h3 is attributed to the multivalency of the analyte and has implications for developing diagnostic assays for additional multimeric allergens.
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Date Issued: 2017-08-11
Identifier: FSU_pmch_28800361, 10.1371/journal.pone.0182935, PMC5553815, 28800361, 28800361, PONE-D-17-08766
Format: Citation

Title: Liraglutide suppression of caloric intake competes with the intake-promoting effects of a palatable cafeteria diet, but does not impact food or macronutrient selection.
Creator: Hyde, Kellie M, Blonde, Ginger D, le Roux, Carel W, Spector, Alan C
Abstract/Description: Liraglutide, a Glucagon-Like Peptide-1 (GLP-1) receptor agonist, is used as a treatment for Type 2 diabetes mellitus and obesity because it improves glycemia and decreases food intake. Here, we tested whether chronic activation of the GLP-1 receptor system with liraglutide would induce decreases in intake accompanied by changes in proportional food or macronutrient intake similar to those seen following RYGB in rats when a variety of palatable food options are available. A "cafeteria diet"...
Show moreLiraglutide, a Glucagon-Like Peptide-1 (GLP-1) receptor agonist, is used as a treatment for Type 2 diabetes mellitus and obesity because it improves glycemia and decreases food intake. Here, we tested whether chronic activation of the GLP-1 receptor system with liraglutide would induce decreases in intake accompanied by changes in proportional food or macronutrient intake similar to those seen following RYGB in rats when a variety of palatable food options are available. A "cafeteria diet" was used that included: laboratory rodent chow, refried beans (low-fat/low-sugar), low-fat yogurt (low-fat/high-sugar), peanut butter (high-fat/low-sugar) and sugar-fat whip (high-fat/high-sugar). Liraglutide (1mg/kg daily, sc, n=6) induced significant reductions in body weight and total caloric intake compared to saline-injected control rats (n=6). Although access to a cafeteria diet induced increases in caloric intake in both groups relative to chow alone, liraglutide still effectively decreased intake compared with saline-injected rats suggesting that chronic GLP-1 activation competes with the energy density and palatability of available food options in modulating ingestive behavior. Even with the substantial effects on overall intake, liraglutide did not change food choice or relative macronutrient intake when compared to pre-treatment baseline. When drug treatment was discontinued, the liraglutide group increased caloric intake and rapidly gained body weight to match that of the saline group. These results demonstrate that, while liraglutide effectively decreases caloric intake and body weight in rats, it does not cause adjustments in relative macronutrient consumption. Our data also show that drug-induced decreases in intake and body weight are not maintained following termination of treatment.
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Date Issued: 2017-08-01
Identifier: FSU_pmch_28366815, 10.1016/j.physbeh.2017.03.045, PMC5545097, 28366815, 28366815, S0031-9384(16)31043-5
Format: Citation

Title: Upregulation of an inward rectifying K+ channel can rescue slow Ca2+ oscillations in K(ATP) channel deficient pancreatic islets.
Creator: Yildirim, Vehpi, Vadrevu, Suryakiran, Thompson, Benjamin, Satin, Leslie S, Bertram, Richard
Abstract/Description: Plasma insulin oscillations are known to have physiological importance in the regulation of blood glucose. In insulin-secreting β-cells of pancreatic islets, K(ATP) channels play a key role in regulating glucose-dependent insulin secretion. In addition, they convey oscillations in cellular metabolism to the membrane by sensing adenine nucleotides, and are thus instrumental in mediating pulsatile insulin secretion. Blocking K(ATP) channels pharmacologically depolarizes the β-cell plasma...
Show morePlasma insulin oscillations are known to have physiological importance in the regulation of blood glucose. In insulin-secreting β-cells of pancreatic islets, K(ATP) channels play a key role in regulating glucose-dependent insulin secretion. In addition, they convey oscillations in cellular metabolism to the membrane by sensing adenine nucleotides, and are thus instrumental in mediating pulsatile insulin secretion. Blocking K(ATP) channels pharmacologically depolarizes the β-cell plasma membrane and terminates islet oscillations. Surprisingly, when K(ATP) channels are genetically knocked out, oscillations in islet activity persist, and relatively normal blood glucose levels are maintained. Compensation must therefore occur to overcome the loss of K(ATP) channels in K(ATP) knockout mice. In a companion study, we demonstrated a substantial increase in Kir2.1 protein occurs in β-cells lacking K(ATP) because of SUR1 deletion. In this report, we demonstrate that β-cells of SUR1 null islets have an upregulated inward rectifying K+ current that helps to compensate for the loss of K(ATP) channels. This current is likely due to the increased expression of Kir2.1 channels. We used mathematical modeling to determine whether an ionic current having the biophysical characteristics of Kir2.1 is capable of rescuing oscillations that are similar in period to those of wild-type islets. By experimentally testing a key model prediction we suggest that Kir2.1 current upregulation is a likely mechanism for rescuing the oscillations seen in islets from mice deficient in K(ATP) channels.
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Date Issued: 2017-07-27
Identifier: FSU_pmch_28749940, 10.1371/journal.pcbi.1005686, PMC5549769, 28749940, 28749940, PCOMPBIOL-D-17-00183
Format: Citation

Title: Locomotor sensitization to intermittent ketamine administration is associated with nucleus accumbens plasticity in male and female rats.
Creator: Strong, C E, Schoepfer, K J, Dossat, A M, Saland, S K, Wright, K N, Kabbaj, M
Abstract/Description: Clinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and...
Show moreClinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and conditioned place preference (CPP) were assayed to evaluate behavioral sensitization to the locomotor activating effects of ketamine and its rewarding properties, respectively. Our results show that while neither males nor females developed CPP, males treated with 5 mg/kg and females treated with either 2.5 or 5 mg/kg ketamine behaviorally sensitized. Furthermore, dendritic spine density was increased in the NAc of both males and females administered 5 mg/kg ketamine, an effect specific to the NAc shell (NAcSh) in males but to both the NAc core (NAcC) and NAcSh in females. Additionally, males administered 5 mg/kg ketamine displayed increased protein expression of ΔfosB, calcium calmodulin kinase II alpha (CaMKIIα), and brain-derived neurotrophic factor (BDNF), an effect not observed in females administered either dose of ketamine. However, males and females administered 5 mg/kg ketamine displayed increased protein expression of AMPA receptors (GluA1). Taken together, low-dose ketamine, when administered intermittently, induces behavioral sensitization at a lower dose in females than males, accompanied by an increase in spine density in the NAc and protein expression changes in pathways commonly implicated in addiction.
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Date Issued: 2017-07-15
Identifier: FSU_pmch_28479397, 10.1016/j.neuropharm.2017.05.003, PMC5520991, 28479397, 28479397, S0028-3908(17)30199-5
Format: Citation

Title: A Splice Variant of Centrosomin Converts Mitochondria to Microtubule-Organizing Centers.
Creator: Chen, Jieyan V, Buchwalter, Rebecca A, Kao, Ling-Rong, Megraw, Timothy L
Abstract/Description: Non-centrosomal microtubule organizing centers (MTOCs) direct microtubule (MT) organization to exert diverse cell-type-specific functions. In Drosophila spermatids, the giant mitochondria provide structural platforms for MT reorganization to support elongation of the extremely long sperm. However, the molecular basis for this mitochondrial MTOC and other non-centrosomal MTOCs has not been discerned. Here we report that Drosophila centrosomin (cnn) expresses two major protein variants: the...
Show moreNon-centrosomal microtubule organizing centers (MTOCs) direct microtubule (MT) organization to exert diverse cell-type-specific functions. In Drosophila spermatids, the giant mitochondria provide structural platforms for MT reorganization to support elongation of the extremely long sperm. However, the molecular basis for this mitochondrial MTOC and other non-centrosomal MTOCs has not been discerned. Here we report that Drosophila centrosomin (cnn) expresses two major protein variants: the centrosomal form (CnnC) and a non-centrosomal form in testes (CnnT). CnnC is established as essential for functional centrosomes, the major MTOCs in animal cells. We show that CnnT is expressed exclusively in testes by alternative splicing and localizes to giant mitochondria in spermatids. In cell culture, CnnT targets to the mitochondrial surface, recruits the MT nucleator γ-tubulin ring complex (γ-TuRC), and is sufficient to convert mitochondria to MTOCs independent of core pericentriolar proteins that regulate MT assembly at centrosomes. We mapped two separate domains in CnnT: one that is necessary and sufficient to target it to mitochondria and another that is necessary and sufficient to recruit γ-TuRCs and nucleate MTs. In elongating spermatids, CnnT forms speckles on the giant mitochondria that are required to recruit γ-TuRCs to organize MTs and support spermiogenesis. This molecular characterization of the mitochondrial MTOC defines a minimal molecular requirement for MTOC generation and implicates the potent role of Cnn (or its related) proteins in the direct regulation of MT assembly and organization of non-centrosomal MTOCs.
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Date Issued: 2017-07-10
Identifier: FSU_pmch_28669756, 10.1016/j.cub.2017.05.090, PMC6147254, 28669756, 28669756, S0960-9822(17)30698-X
Format: Citation

Title: Cell-cycle dynamics of chromosomal organization at single-cell resolution.
Creator: Nagano, Takashi, Lubling, Yaniv, Várnai, Csilla, Dudley, Carmel, Leung, Wing, Baran, Yael, Mendelson Cohen, Netta, Wingett, Steven, Fraser, Peter, Tanay, Amos
Abstract/Description: Chromosomes in proliferating metazoan cells undergo marked structural metamorphoses every cell cycle, alternating between highly condensed mitotic structures that facilitate chromosome segregation, and decondensed interphase structures that accommodate transcription, gene silencing and DNA replication. Here we use single-cell Hi-C (high-resolution chromosome conformation capture) analysis to study chromosome conformations in thousands of individual cells, and discover a continuum of cis...
Show moreChromosomes in proliferating metazoan cells undergo marked structural metamorphoses every cell cycle, alternating between highly condensed mitotic structures that facilitate chromosome segregation, and decondensed interphase structures that accommodate transcription, gene silencing and DNA replication. Here we use single-cell Hi-C (high-resolution chromosome conformation capture) analysis to study chromosome conformations in thousands of individual cells, and discover a continuum of cis-interaction profiles that finely position individual cells along the cell cycle. We show that chromosomal compartments, topological-associated domains (TADs), contact insulation and long-range loops, all defined by bulk Hi-C maps, are governed by distinct cell-cycle dynamics. In particular, DNA replication correlates with a build-up of compartments and a reduction in TAD insulation, while loops are generally stable from G1 to S and G2 phase. Whole-genome three-dimensional structural models reveal a radial architecture of chromosomal compartments with distinct epigenomic signatures. Our single-cell data therefore allow re-interpretation of chromosome conformation maps through the prism of the cell cycle.
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Date Issued: 2017-07-05
Identifier: FSU_pmch_28682332, 10.1038/nature23001, PMC5567812, 28682332, 28682332, nature23001
Format: Citation

Title: The mA pathway facilitates sex determination in Drosophila.
Creator: Kan, Lijuan, Grozhik, Anya V, Vedanayagam, Jeffrey, Patil, Deepak P, Pang, Nan, Lim, Kok-Seong, Huang, Yi-Chun, Joseph, Brian, Lin, Ching-Jung, Despic, Vladimir, Guo, Jian, Yan,...
Show moreKan, Lijuan, Grozhik, Anya V, Vedanayagam, Jeffrey, Patil, Deepak P, Pang, Nan, Lim, Kok-Seong, Huang, Yi-Chun, Joseph, Brian, Lin, Ching-Jung, Despic, Vladimir, Guo, Jian, Yan, Dong, Kondo, Shu, Deng, Wu-Min, Dedon, Peter C, Jaffrey, Samie R, Lai, Eric C
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Abstract/Description: The conserved modification N-methyladenosine (mA) modulates mRNA processing and activity. Here, we establish the Drosophila system to study the mA pathway. We first apply miCLIP to map mA across embryogenesis, characterize its mA 'writer' complex, validate its YTH 'readers' CG6422 and YT521-B, and generate mutants in five mA factors. While mA factors with additional roles in splicing are lethal, mA-specific mutants are viable but present certain developmental and behavioural defects. Notably,...
Show moreThe conserved modification N-methyladenosine (mA) modulates mRNA processing and activity. Here, we establish the Drosophila system to study the mA pathway. We first apply miCLIP to map mA across embryogenesis, characterize its mA 'writer' complex, validate its YTH 'readers' CG6422 and YT521-B, and generate mutants in five mA factors. While mA factors with additional roles in splicing are lethal, mA-specific mutants are viable but present certain developmental and behavioural defects. Notably, mA facilitates the master female determinant Sxl, since multiple mA components enhance female lethality in Sxl sensitized backgrounds. The mA pathway regulates Sxl processing directly, since miCLIP data reveal Sxl as a major intronic mA target, and female-specific Sxl splicing is compromised in multiple mA pathway mutants. YT521-B is a dominant mA effector for Sxl regulation, and YT521-B overexpression can induce female-specific Sxl splicing. Overall, our transcriptomic and genetic toolkit reveals in vivo biologic function for the Drosophila mA pathway.
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Date Issued: 2017-07-04
Identifier: FSU_pmch_28675155, 10.1038/ncomms15737, PMC5500889, 28675155, 28675155, ncomms15737
Format: Citation

Title: Stability of patient-specific features of altered DNA replication timing in xenografts of primary human acute lymphoblastic leukemia.
Creator: Sasaki, Takayo, Rivera-Mulia, Juan Carlos, Vera, Daniel, Zimmerman, Jared, Das, Sunny, Padget, Michelle, Nakamichi, Naoto, Chang, Bill H, Tyner, Jeff, Druker, Brian J, Weng,...
Show moreSasaki, Takayo, Rivera-Mulia, Juan Carlos, Vera, Daniel, Zimmerman, Jared, Das, Sunny, Padget, Michelle, Nakamichi, Naoto, Chang, Bill H, Tyner, Jeff, Druker, Brian J, Weng, Andrew P, Civin, Curt I, Eaves, Connie J, Gilbert, David M
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Abstract/Description: Genome-wide DNA replication timing (RT) profiles reflect the global three-dimensional chromosome architecture of cells. They also provide a comprehensive and unique megabase-scale picture of cellular epigenetic state. Thus, normal differentiation involves reproducible changes in RT, and transformation generally perturbs these, although the potential effects of altered RT on the properties of transformed cells remain largely unknown. A major challenge to interrogating these issues in human...
Show moreGenome-wide DNA replication timing (RT) profiles reflect the global three-dimensional chromosome architecture of cells. They also provide a comprehensive and unique megabase-scale picture of cellular epigenetic state. Thus, normal differentiation involves reproducible changes in RT, and transformation generally perturbs these, although the potential effects of altered RT on the properties of transformed cells remain largely unknown. A major challenge to interrogating these issues in human acute lymphoid leukemia (ALL) is the low proliferative activity of most of the cells, which may be further reduced in cryopreserved samples and difficult to overcome in vitro. In contrast, the ability of many human ALL cell populations to expand when transplanted into highly immunodeficient mice is well documented. To examine the stability of DNA RT profiles of serially passaged xenografts of primary human B- and T-ALL cells, we first devised a method that circumvents the need for bromodeoxyuridine incorporation to distinguish early versus late S-phase cells. Using this and more standard protocols, we found consistently strong retention in xenografts of the original patient-specific RT features. Moreover, in a case in which genomic analyses indicated changing subclonal dynamics in serial passages, the RT profiles tracked concordantly. These results indicate that DNA RT is a relatively stable feature of human ALLs propagated in immunodeficient mice. In addition, they suggest the power of this approach for future interrogation of the origin and consequences of altered DNA RT in ALL.
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Date Issued: 2017-07-01
Identifier: FSU_pmch_28433605, 10.1016/j.exphem.2017.04.004, PMC5491210, 28433605, 28433605, S0301-472X(17)30136-4
Format: Citation

Title: Selection To Increase Expression, Not Sequence Diversity, Precedes Gene Family Origin and Expansion in Rattlesnake Venom.
Creator: Margres, Mark J, Bigelow, Alyssa T, Lemmon, Emily Moriarty, Lemmon, Alan R, Rokyta, Darin R
Abstract/Description: Gene duplication is the primary mechanism leading to new genes and phenotypic novelty, but the proximate evolutionary processes underlying gene family origin, maintenance, and expansion are poorly understood. Although sub- and neofunctionalization provide clear long-term advantages, selection does not act with foresight, and unless a redundant gene copy provides an immediate fitness advantage, the copy will most likely be lost. Many models for the evolution of genes immediately following...
Show moreGene duplication is the primary mechanism leading to new genes and phenotypic novelty, but the proximate evolutionary processes underlying gene family origin, maintenance, and expansion are poorly understood. Although sub- and neofunctionalization provide clear long-term advantages, selection does not act with foresight, and unless a redundant gene copy provides an immediate fitness advantage, the copy will most likely be lost. Many models for the evolution of genes immediately following duplication have been proposed, but the robustness and applicability of these models is unclear because of the lack of data at the population level. We used qPCR, protein expression data, genome sequencing, and hybrid enrichment to test three competing models that differ in whether selection favoring the spread of duplicates acts primarily on expression level or sequence diversity for specific toxin-encoding loci in the eastern diamondback rattlesnake (). We sampled 178 individuals and identified significant inter- and intrapopulation variation in copy number, demonstrated that copy number was significantly and positively correlated with protein expression, and found little to no sequence variation across paralogs in all populations. Collectively, these results demonstrate that selection for increased expression, not sequence diversity, was the proximate evolutionary process underlying gene family origin and expansion, providing data needed to resolve the debate over which evolutionary processes govern the fates of gene copies immediately following duplication.
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Date Issued: 2017-07-01
Identifier: FSU_pmch_28476866, 10.1534/genetics.117.202655, PMC5500151, 28476866, 28476866, genetics.117.202655
Format: Citation

Title: Estradiol modulates the anorexic response to central glucagon-like peptide 1.
Creator: Maske, Calyn B, Jackson, Christine M, Terrill, Sarah J, Eckel, Lisa A, Williams, Diana L
Abstract/Description: Estrogens suppress feeding in part by enhancing the response to satiation signals. Glucagon-like peptide 1 (GLP-1) acts on receptor populations both peripherally and centrally to affect food intake. We hypothesized that modulation of the central GLP-1 system is one of the mechanisms underlying the effects of estrogens on feeding. We assessed the anorexic effect of 0, 1, and 10μg doses of GLP-1 administered into the lateral ventricle of bilaterally ovariectomized (OVX) female rats on a cyclic...
Show moreEstrogens suppress feeding in part by enhancing the response to satiation signals. Glucagon-like peptide 1 (GLP-1) acts on receptor populations both peripherally and centrally to affect food intake. We hypothesized that modulation of the central GLP-1 system is one of the mechanisms underlying the effects of estrogens on feeding. We assessed the anorexic effect of 0, 1, and 10μg doses of GLP-1 administered into the lateral ventricle of bilaterally ovariectomized (OVX) female rats on a cyclic regimen of either 2μg β-estradiol-3-benzoate (EB) or oil vehicle 30min prior to dark onset on the day following hormone treatment. Central GLP-1 treatment significantly suppressed food intake in EB-treated rats at both doses compared to vehicle, whereas only the 10μg GLP-1 dose was effective in oil-treated rats. To follow up, we examined whether physiologic-dose cyclic estradiol treatment influences GLP-1-induced c-Fos in feeding-relevant brain areas of OVX females. GLP-1 significantly increased c-Fos expression in the area postrema (AP) and nucleus of the solitary tract (NTS), and the presence of estrogens may be required for this effect in the paraventricular nucleus of the hypothalamus (PVN). Together, these data suggest that modulation of the central GLP-1 system may be one of the mechanisms by which estrogens suppress food intake, and highlight the PVN as a region of interest for future investigation.
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Date Issued: 2017-07-01
Identifier: FSU_pmch_28558993, 10.1016/j.yhbeh.2017.05.012, PMC5555302, 28558993, 28558993, S0018-506X(17)30012-0
Format: Citation

Title: Tet1 in Nucleus Accumbens Opposes Depression- and Anxiety-Like Behaviors.
Creator: Feng, Jian, Pena, Catherine J, Purushothaman, Immanuel, Engmann, Olivia, Walker, Deena, Brown, Amber N, Issler, Orna, Doyle, Marie, Harrigan, Eileen, Mouzon, Ezekiell, Vialou,...
Show moreFeng, Jian, Pena, Catherine J, Purushothaman, Immanuel, Engmann, Olivia, Walker, Deena, Brown, Amber N, Issler, Orna, Doyle, Marie, Harrigan, Eileen, Mouzon, Ezekiell, Vialou, Vincent, Shen, Li, Dawlaty, Meelad M, Jaenisch, Rudolf, Nestler, Eric J
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Abstract/Description: Depression is a leading cause of disease burden, yet current therapies fully treat
Show moreDepression is a leading cause of disease burden, yet current therapies fully treat <50% of affected individuals. Increasing evidence implicates epigenetic mechanisms in depression and antidepressant action. Here we examined a possible role for the DNA dioxygenase, ten-eleven translocation protein 1 (TET1), in depression-related behavioral abnormalities. We applied chronic social defeat stress, an ethologically validated mouse model of depression-like behaviors, and examined Tet1 expression changes in nucleus accumbens (NAc), a key brain reward region. We show decreased Tet1 expression in NAc in stress-susceptible mice only. Surprisingly, selective knockout of Tet1 in NAc neurons of adult mice produced antidepressant-like effects in several behavioral assays. To identify Tet1 targets that mediate these actions, we performed RNAseq on NAc after conditional deletion of Tet1 and found that immune-related genes are the most highly dysregulated. Moreover, many of these genes are also upregulated in the NAc of resilient mice after chronic social defeat stress. These findings reveal a novel role for TET1, an enzyme important for DNA hydroxymethylation, in the brain's reward circuitry in modulating stress responses in mice. We also identify a subset of genes that are regulated by TET1 in this circuitry. These findings provide new insight into the pathophysiology of depression, which can aid in future antidepressant drug discovery efforts.
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Date Issued: 2017-07-01
Identifier: FSU_pmch_28074830, 10.1038/npp.2017.6, PMC5518912, 28074830, 28074830, npp20176
Format: Citation

Title: Exercise training reverses age-induced diastolic dysfunction and restores coronary microvascular function.
Creator: Hotta, Kazuki, Chen, Bei, Behnke, Bradley J, Ghosh, Payal, Stabley, John N, Bramy, Jeremy A, Sepulveda, Jaime L, Delp, Michael D, Muller-Delp, Judy M
Abstract/Description: In a rat model of ageing that is free of atherosclerosis or hypertension, E/A, a diagnostic measure of diastolic filling, decreases, and isovolumic relaxation time increases, indicating that both active and passive ventricular relaxation are impaired with advancing age. Resting coronary blood flow and coronary functional hyperaemia are reduced with age, and endothelium-dependent vasodilatation declines with age in coronary resistance arterioles. Exercise training reverses age-induced declines...
Show moreIn a rat model of ageing that is free of atherosclerosis or hypertension, E/A, a diagnostic measure of diastolic filling, decreases, and isovolumic relaxation time increases, indicating that both active and passive ventricular relaxation are impaired with advancing age. Resting coronary blood flow and coronary functional hyperaemia are reduced with age, and endothelium-dependent vasodilatation declines with age in coronary resistance arterioles. Exercise training reverses age-induced declines in diastolic and coronary microvascular function. Thus, microvascular dysfunction and inadequate coronary perfusion are likely mechanisms of diastolic dysfunction in aged rats. Exercise training, initiated at an advanced age, reverses age-related diastolic and microvascular dysfunction; these data suggest that late-life exercise training can be implemented to improve coronary perfusion and diastolic function in the elderly. The risk for diastolic dysfunction increases with advancing age. Regular exercise training ameliorates age-related diastolic dysfunction; however, the underlying mechanisms have not been identified. We investigated whether (1) microvascular dysfunction contributes to the development of age-related diastolic dysfunction, and (2) initiation of late-life exercise training reverses age-related diastolic and microvascular dysfunction. Young and old rats underwent 10 weeks of exercise training or remained as sedentary, cage-controls. Isovolumic relaxation time (IVRT), early diastolic filling (E/A), myocardial performance index (MPI) and aortic stiffness (pulse wave velocity; PWV) were evaluated before and after exercise training or cage confinement. Coronary blood flow and vasodilatory responses of coronary arterioles were evaluated in all groups at the end of training. In aged sedentary rats, compared to young sedentary rats, a 42% increase in IVRT, a 64% decrease in E/A, and increased aortic stiffness (PWV: 6.36 ± 0.47 vs.4.89 ± 0.41, OSED vs. YSED, P < 0.05) was accompanied by impaired coronary blood flow at rest and during exercise. Endothelium-dependent vasodilatation was impaired in coronary arterioles from aged rats (maximal relaxation to bradykinin: 56.4 ± 5.1% vs. 75.3 ± 5.2%, OSED vs. YSED, P < 0.05). After exercise training, IVRT, a measure of active ventricular relaxation, did not differ between old and young rats. In old rats, exercise training reversed the reduction in E/A, reduced aortic stiffness, and eliminated impairment of coronary blood flow responses and endothelium-dependent vasodilatation. Thus, age-related diastolic and microvascular dysfunction are reversed by late-life exercise training. The restorative effect of exercise training on coronary microvascular function may result from improved endothelial function.
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Date Issued: 2017-06-15
Identifier: FSU_pmch_28295341, 10.1113/JP274172, PMC5471361, 28295341, 28295341
Format: Citation

Title: Regulation of BAZ1A and nucleosome positioning in the nucleus accumbens in response to cocaine.
Creator: Sun, HaoSheng, Damez-Werno, Diane M, Scobie, Kimberly N, Shao, Ning-Yi, Dias, Caroline, Rabkin, Jacqui, Wright, Katherine N, Mouzon, Ezekiell, Kabbaj, Mohamed, Neve, Rachael,...
Show moreSun, HaoSheng, Damez-Werno, Diane M, Scobie, Kimberly N, Shao, Ning-Yi, Dias, Caroline, Rabkin, Jacqui, Wright, Katherine N, Mouzon, Ezekiell, Kabbaj, Mohamed, Neve, Rachael, Turecki, Gustavo, Shen, Li, Nestler, Eric J
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Abstract/Description: Chromatin regulation, in particular ATP-dependent chromatin remodelers, have previously been shown to be important in the regulation of reward-related behaviors in animal models of mental illnesses. Here we demonstrate that BAZ1A, an accessory subunit of the ISWI family of chromatin remodeling complexes, is downregulated in the nucleus accumbens (NAc) of mice exposed repeatedly to cocaine and of cocaine-addicted humans. Viral-mediated overexpression of BAZ1A in mouse NAc reduces cocaine...
Show moreChromatin regulation, in particular ATP-dependent chromatin remodelers, have previously been shown to be important in the regulation of reward-related behaviors in animal models of mental illnesses. Here we demonstrate that BAZ1A, an accessory subunit of the ISWI family of chromatin remodeling complexes, is downregulated in the nucleus accumbens (NAc) of mice exposed repeatedly to cocaine and of cocaine-addicted humans. Viral-mediated overexpression of BAZ1A in mouse NAc reduces cocaine reward as assessed by conditioned place preference (CPP), but increases cocaine-induced locomotor activation. Furthermore, we investigate nucleosome repositioning genome-wide by conducting chromatin immunoprecipitation (ChIP)-sequencing for total H3 in NAc of control mice and after repeated cocaine administration, and find extensive nucleosome occupancy and shift changes across the genome in response to cocaine exposure. These findings implicate BAZ1A in molecular and behavioral plasticity to cocaine and offer new insight into the pathophysiology of cocaine addiction.
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Date Issued: 2017-06-14
Identifier: FSU_pmch_28412501, 10.1016/j.neuroscience.2017.04.007, PMC5473651, 28412501, 28412501, S0306-4522(17)30246-4
Format: Citation

Title: Upregulation of minichromosome maintenance complex component 3 during epithelial-to-mesenchymal transition in human prostate cancer.
Creator: Stewart, Paul A, Khamis, Zahraa I, Zhau, Haiyen E, Duan, Peng, Li, Quanlin, Chung, Leland W K, Sang, Qing-Xiang Amy
Abstract/Description: Metastasis is often associated with epithelial-to-mesenchymal transition (EMT). To understand the molecular mechanisms of this process, we conducted proteomic analysis of androgen-repressed cancer of the prostate (ARCaP), an experimental model of metastatic human prostate cancer. The protein signatures of epithelial (ARCaPE) and mesenchymal (ARCaPM) cells were consistent with their phenotypes. Importantly, the expression of mini-chromosome maintenance 3 (MCM3) protein, a crucial subunit of...
Show moreMetastasis is often associated with epithelial-to-mesenchymal transition (EMT). To understand the molecular mechanisms of this process, we conducted proteomic analysis of androgen-repressed cancer of the prostate (ARCaP), an experimental model of metastatic human prostate cancer. The protein signatures of epithelial (ARCaPE) and mesenchymal (ARCaPM) cells were consistent with their phenotypes. Importantly, the expression of mini-chromosome maintenance 3 (MCM3) protein, a crucial subunit of DNA helicase, was significantly higher in ARCaPM cells than that of ARCaPE cells. This increased MCM3 protein expression level was verified using Western blot analysis of the ARCaP cell lineages. Furthermore, immunohistochemical analysis of MCM3 protein levels in human prostate tissue specimens showed elevated expression in bone metastasis and advanced human prostate cancer tissue samples. Subcutaneous injection experiments using ARCaPE and ARCaPM cells in a mouse model also revealed increased MCM3 protein levels in mesenchymal-derived tumors. This study identifies MCM3 as an upregulated molecule in mesenchymal phenotype of human prostate cancer cells and advanced human prostate cancer specimens, suggesting MCM3 may be a new potential drug target for prostate cancer treatment.
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Date Issued: 2017-06-13
Identifier: FSU_pmch_28424404, 10.18632/oncotarget.16835, PMC5503607, 28424404, 28424404, 16835
Format: Citation

Title: Histone posttranslational modifications predict specific alternative exon subtypes in mammalian brain.
Creator: Hu, Qiwen, Kim, Eun Ji, Feng, Jian, Grant, Gregory R, Heller, Elizabeth A
Abstract/Description: A compelling body of literature, based on next generation chromatin immunoprecipitation and RNA sequencing of reward brain regions indicates that the regulation of the epigenetic landscape likely underlies chronic drug abuse and addiction. It is now critical to develop highly innovative computational strategies to reveal the relevant regulatory transcriptional mechanisms that may underlie neuropsychiatric disease. We have analyzed chromatin regulation of alternative splicing, which is...
Show moreA compelling body of literature, based on next generation chromatin immunoprecipitation and RNA sequencing of reward brain regions indicates that the regulation of the epigenetic landscape likely underlies chronic drug abuse and addiction. It is now critical to develop highly innovative computational strategies to reveal the relevant regulatory transcriptional mechanisms that may underlie neuropsychiatric disease. We have analyzed chromatin regulation of alternative splicing, which is implicated in cocaine exposure in mice. Recent literature has described chromatin-regulated alternative splicing, suggesting a novel function for drug-induced neuroepigenetic remodeling. However, the extent of the genome-wide association between particular histone modifications and alternative splicing remains unexplored. To address this, we have developed novel computational approaches to model the association between alternative splicing and histone posttranslational modifications in the nucleus accumbens (NAc), a brain reward region. Using classical statistical methods and machine learning to combine ChIP-Seq and RNA-Seq data, we found that specific histone modifications are strongly associated with various aspects of differential splicing. H3K36me3 and H3K4me1 have the strongest association with splicing indicating they play a significant role in alternative splicing in brain reward tissue.
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Date Issued: 2017-06-13
Identifier: FSU_pmch_28609483, 10.1371/journal.pcbi.1005602, PMC5487056, 28609483, 28609483, PCOMPBIOL-D-17-00526
Format: Citation

Department of Biomedical Sciences (125)	+ -
Department of Biological Science (71)	+ -
Program in Neuroscience (42)	+ -
Department of Psychology (23)	+ -
Institute of Molecular Biophysics (21)	+ -

Department of Chemistry and Biochemistry (12)	+ -
Department of Mathematics (8)	+ -
National High Magnetic Field Laboratory (7)	+ -
Department of Scientific Computing (6)	+ -
Department of Nutrition, Food and Exercise Sciences (5)	+ -
Center for Genomics and Personalized Medicine (4)	+ -
Department of Physics (4)	+ -
Department of Statistics (3)	+ -
Center for Brain Repair (2)	+ -
Department of Anthropology (2)	+ -
College of Medicine (1)	+ -
Department of Behavioral Sciences and Social Medicine (1)	+ -
Department of Chemical and Biomedical Engineering (1)	+ -
Department of Computer Science (1)	+ -
Department of Earth, Ocean and Atmospheric Science (1)	+ -
Department of Geography (1)	+ -
Florida Learning Disability Research Center (1)	+ -
Translational Science Laboratory (1)	+ -

Male (97)	+ -
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Humans (77)	+ -
Female (61)	+ -
Rats (53)	+ -

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Mice, Inbred C57BL (31)	+ -
Disease Models, Animal (26)	+ -
Mice, Knockout (22)	+ -
Cells, Cultured (16)	+ -
Protein Binding (14)	+ -
Cell Line (13)	+ -
Drosophila Proteins/metabolism (13)	+ -
Mutation (13)	+ -
RNA, Messenger/metabolism (13)	+ -
Time Factors (13)	+ -
Drosophila Proteins/genetics (12)	+ -
Gene Expression Regulation (12)	+ -
HEK293 Cells (12)	+ -
Mice, Transgenic (11)	+ -
Neurons/metabolism (11)	+ -
Phenotype (11)	+ -
Molecular Sequence Data (10)	+ -
Neurons/physiology (10)	+ -
Pregnancy (10)	+ -
Sex Characteristics (10)	+ -
Species Specificity (10)	+ -
Calcium/metabolism (9)	+ -
Dose-Response Relationship, Drug (9)	+ -

text (257)	+ -
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