Ethanol inhibits the proliferation of neural stem cells in the fetal, adolescent, and adult brain. The consequences are cognitive deficits associated with fetal alcohol spectrum disorder and alcohol use disorder. We tested the hypothesis that ethanol affects progression through cell cycle checkpoints by differentially modifying transcriptional processes. Monolayer cultures of NS-5 neural stem cells were treated for 48 hr with the mitogenic agent FGF2 or the anti-mitogenic TGF1 in the absence or presence of ethanol. Cell cycle elongation was induced by a global down-regulation of genes involved in cell cycle progression, including the cyclin E system. Checkpoint regulation occurred downstream of p21 and Jun-oncogene signaling cascades. Thus, ethanol can affect cell cycle progression by altering transcript expression of strategic genes downstream of the G1/S checkpoint.
Ethanol-induced methylation of cell cycle genes in neural stem cells.
Specimen part, Treatment
View SamplesThe Ag receptors on alpha/beta and gamma/delta T cells differ not only in the nature of the ligands that they recognize but also in their signaling potential. We hypothesized that the differences in alpha/beta - and gamma/delta TCR signal transduction were due to differences in the intracellular signaling pathways coupled to these two TCRs. To investigate this, we employed transcriptional profiling to identify genes encoding signaling molecules that are differentially expressed in mature alpha/beta and gamma/delta T cell populations. Unexpectedly, we found that B lymphoid kinase (Blk), a Src family kinase expressed primarily in B cells, is expressed in gamma/delta T cells but not in alpha/beta T cells. Analysis of Blk-deficient mice revealed that Blk is required for the development of IL-17-producing gamma/delta T cells. Furthermore, Blk is expressed in lymphoid precursors and, in this capacity, plays a role in regulating thymus cellularity during ontogeny.
Unexpected role for the B cell-specific Src family kinase B lymphoid kinase in the development of IL-17-producing γδ T cells.
Specimen part
View SamplesPurpose: Investigate the molecular determinants of retinal regeneration in adult vertebrates by analyzing the gene expression profiles of control and post-lesion retina of adult zebrafish, a system that regenerates following injury. Methods: Gene expression profiles of zebrafish retina and brain were determined with DNA microarray, RT-PCR, and real-time quantitative PCR analyses. Damaged retinas and their corresponding controls were analyzed 2-5 days post-lesion (acute injury condition) or 14 d post-lesion (cell regeneration condition). Results: Expected similarities and differences in the gene expression profile of zebrafish retina and brain were observed, confirming the applicability of the gene expression techniques. Mechanical lesion of retina triggered significant, time-dependent changes in retinal gene expression. The induced transcriptional changes were consistent with cellular phenomena known to occur, in a time-dependent manner, subsequent to retinal lesion, including cell cycle progression, axonal regeneration, and regenerative cytogenesis. Conclusions: The results indicate that retinal regeneration in adult zebrafish involves a complex set of induced, targeted changes in gene transcription, and suggest that these molecular changes underlie the ability of the adult vertebrate retina to regenerate. Keywords: time course; injury response; cellular correlation Control brain and retina (unlesioned); Control and lesioned retina (matched animals, at least n = 8 for each condition).
Gene expression profiles of intact and regenerating zebrafish retina.
Specimen part, Subject, Time
View SamplesT cells that encounter cultured ocular pigment epithelial cells in vitro are inhibited from undergoing T cell receptor-triggered activation. Because retinal pigment epithelial (RPE) cells are able to suppress T-cell activation, we studied whether RPE cells could suppress cytokine production by activated T helper (Th) cells. In this study we showed that primary cultured RPE cells greatly suppressed activation of bystander CD4+ T cells in vitro, especially the cytokine production by the target T helper cells (Th1 cells, Th2 cells, Th17 cells, but not Th3 cells). Cultured RPE cells and RPE-supernatants significantly suppressed IL-17 producing CD4+ T cells, and RPE cells fully suppressed polarized Th17 cell lines that induced by recombinant proteins, IL-6 and TGFb2. Moreover, RPE cells failed to suppress IL-17 producing T cells in the presence of rIL-6. In addition, Th17 cells exposed to RPE were suppressed via TGFb, which produce RPE cells. These results indicate that retinal PE cells have immunosuppressive capacity in order to inhibit Th17-type effector T cells. Thus, ocular resident cells play a role in establishing immune regulation in the eye.
No associated publication
Sex, Specimen part
View SamplesThese samples are part of the MMRRC study conducted at UAlbany
No associated publication
Sex, Age, Specimen part
View SamplesDifferential gene expression of cerebral cortex might be responsible for distinct neurovascular developments between different mouse strains
A novel genetic locus modulates infarct volume independently of the extent of collateral circulation.
Sex, Specimen part
View SamplesAtrial fibrillation (AF) is a progressive arrhythmia for which current therapy is inadequate. During AF, rapid stimulation causes atrial remodeling that promotes further AF. The cellular signals that trigger this process remain poorly understood, however, and elucidation of these factors would likely identify new therapeutic targets. We have previously shown that immortalized mouse atrial (HL-1) myocytes subjected to 24 hr of rapid stimulation in culture undergo remodeling similar to that seen in animal models of atrial tachycardia (AT) and human AF. This preparation is devoid of confounding in vivo variables that can modulate gene expression (e.g., hemodynamics). Therefore, we investigated the transcriptional profile associated with early atrial cell remodeling. RNA was harvested from HL-1 cells cultured for 24 hr in the absence and presence of rapid stimulation and subjected to microarray analysis. Data were normalized using Robust Multichip Analysis (RMA), and genes exhibiting significant differential expression were identified using the Significance Analysis of Microarrays (SAM) method. Using this approach, 919 genes were identified that were significantly altered with rapid stimulation (763 up-regulated and 156 down-regulated). For many individual transcripts, changes typical of AF/AT were observed, with marked up-regulation of genes encoding BNP and ANP precursors, heat shock proteins, and MAP kinases, while novel signaling pathways and molecules were also identified. Both stress and survival response were evident, as well as up-regulation of multiple transcription factors. Genes were also functionally classified based on cellular component, biologic process, and molecular function using the Gene Ontology database to permit direct comparison of our data with other gene sets regulated in human AF and experimental AT. For broad categories of genes grouped by functional classification, there was striking conservation between rapidly stimulated HL-1 cells and AF/AT. Results were confirmed using real-time quantitative RT-PCR on 13 genes selected by physiological relevance in AF/AT and regulation in the microarray analysis (up, down, and nonregulated). Rapidly-stimulated atrial myocytes provide a complementary experimental paradigm to explore the initial cellular signals in AT remodeling to identify novel targets in the treatment of AF.
No associated publication
No sample metadata fields
View SamplesIn order to elucidate the molecular mechanisms underlying individual variation in sensitivity to ethanol we profiled the prefrontal cortex transcriptomes of two inbred strains that exhibit divergent responses to acute ethanol, the C57BL6/J (B6) and DBA/2J (D2) strains, as well as 27 members of the BXD recombinant inbred panel, which was derived from a B6 x D2 cross. With this dataset we were able to identify several gene co-expression networks that were robustly altered by acute ethanol across the BXD panel. These ethanol-responsive gene-enriched networks were heavily populated by genes regulating synaptic transmission and neuroplasticity, and showed strong genetic linkage to discreet chromosomal loci. Network-based measurements of node importance identified several hub genes as established regulators of ethanol response phenotypes, while other hubs represent novel candidate modulators of ethanol responses.
Genetic dissection of acute ethanol responsive gene networks in prefrontal cortex: functional and mechanistic implications.
Sex, Specimen part
View SamplesThroughout postnatal life in mammals, neural stem cells (NSCs) are located in the subventricular zone (SVZ) of the lateral ventricles. The greatest diversity of neuronal and glial lineages they generate occurs during early postnatal life in a region-specific manner. In order to evaluate potential heterogeneity in the NSC pool, we microdissected the dorsal and lateral SVZ at different postnatal ages and isolated NSCs and their immediate progeny based on their expression of Hes5-EGFP/Prominin1 and Ascl1-EGFP, respectively. Whole genome comparative transcriptome analysis revealed transcriptional regulators as major hallmarks that sustain postnatal SVZ regionalization. Manipulation of single genes encoding for locally enriched transcription factors influenced NSC specification indicating that the fate of regionalized postnatal SVZ NSCs can be readily modified . These findings reveal functional heterogeneity of NSCs in the postnatal SVZ and provide targets to recruit region-specific lineages in regenerative contexts.
Transcriptional Hallmarks of Heterogeneous Neural Stem Cell Niches of the Subventricular Zone.
Specimen part
View SamplesZebrafish (Danio rerio) were obtained from the Zebrafish Research Facility maintained in the Center for Environmental Biotechnology at the University of Tennessee. Fish husbandry, spawning, and experimental procedures were conducted with approval from the University of Tennessee Institutional Animal Care and Use Committee (Protocol #1690-1007). Water for holding fish and conducting experiments (hereafter referred to as fish water) consisted of MilliQ water (Millipore, Bedford, MA) with ions added: 19 mg/L NaHCO3, 1 mg/L sea salt (Instant Ocean Synthetic Sea Salt, Mentor, OH), 10 mg/L CaSO4, 10 mg/L MgSO4, 2 mg/L KCl. Embryos were obtained by spawning adult fish with no history of contaminant exposure. Fertilization of embryos took place at the same time ( 15 min.), such that larvae used in experiments were of similar age at the time of exposure. All activities (maintenance of adult fish, spawning, and experiments) were conducted in an environmental chamber with a temperature of 27 1 C and 14:10h light:dark photoperiod.
Global gene expression profiling in larval zebrafish exposed to microcystin-LR and microcystis reveals endocrine disrupting effects of Cyanobacteria.
No sample metadata fields
View Samples