During embryogenesis, many key transcription factors are used repeatedly, achieving different outcomes depending on cell type and developmental stage. The epigenetic modification of the genome functions as a memory of a cells developmental history, and it has been proposed that such modification shapes the cellular response to transcription factors. To investigate the role of DNA methylation in the response to transcription factor Gata4, we examined expression profiles of Dnmt3a-/-Dnmt3b-/- ES cell-derived mesoderm cells cultured for 4 days with or without Gata4 activation, as well as the wild-type counterparts, using Affymetrix microarrays.
DNA methylation restricts lineage-specific functions of transcription factor Gata4 during embryonic stem cell differentiation.
Specimen part
View SamplesThe adult mammalian brain is composed of distinct regions that have specialized roles. To dissect molecularly this complex structure, we conducted a project, named the BrainStars (B*) project, in which we sampled ~50 small brain regions, including sensory centers and centers for motion, time, memory, fear, and feeding. To avoid confusion from temporal differences in gene expression, we sampled each region every 4 hours for 24 hours, and pooled the sample sets for DNA-microarray assays. Therefore, we focused only on spatial differences in gene expression. We then used informatics to identify candidates for (1) genes with high or low expression in specific regions, (2) switch-like genes with bimodal or multimodal expression patterns, and (3) genes with a uni-modal expression pattern that exhibit stable or variable levels of expression across brain regions. We used our findings to develop an integrated database (http://brainstars.org/) for exploring genome-wide expression in the adult mouse brain.
Quantitative expression profile of distinct functional regions in the adult mouse brain.
Sex, Specimen part
View SamplesLiving organisms detect seasonal changes in day length (photoperiod), and alter their physiological functions accordingly, to fit seasonal environmental changes. This photoperiodic system is implicated in seasonal affective disorders and the season-associated symptoms observed in bipolar disease and schizophrenia. Thyroid-stimulating hormone beta subunit (Tshb), induced in the pars tuberalis (PT), plays a key role in the pathway that regulates animal photoperiodism. However, the upstream inducers of Tshb expression remain unknown. Here we show that late-night light stimulation acutely triggers the Eya3-Six1 pathway, which directly induces Tshb expression. Using melatonin-proficient CBA/N mice, which preserve the photoperiodic Tshb-expression response, we performed a genome-wide expression analysis of the PT under chronic short-day and long-day conditions. These data comprehensively identified long-day and short-day genes, and indicated that late-night light stimulation induces long-day genes. We verified this by advancing and extending the light period by 8 hours, which acutely induced Tshb expression, within one day. In a genome-wide expression analysis under this condition, we searched for candidate upstream genes by looking for expression that preceded Tshbs, and identified Eya3 gene. These results elucidate the comprehensive transcriptional photoperiodic response in the PT, revealing the complex regulation of Tshb expression and unexpectedly rapid response to light changes in the mammalian photoperiodic system.
Acute induction of Eya3 by late-night light stimulation triggers TSHβ expression in photoperiodism.
Sex, Age, Specimen part, Time
View SamplesThe adult mammalian brain is composed of distinct regions that have specialized roles. The BF/POA regions are thought to have an important role in the regulation of sleep/wake behavior. However, genetic markers of the responsible cells for the regulation of sleep/wake behavior are largely unknown. To identify the molecular markers of the BF/POA regions, we sampled the BF/POA regions and compared gene expression in the BF/POA regions with those of other brain regions which we previously reported in the BrainStars (B*) project, in which we sampled ~50 small brain regions, including sensory centers and centers for motion, time, memory, fear, and feeding.
Muscarinic Acetylcholine Receptors Chrm1 and Chrm3 Are Essential for REM Sleep.
Sex, Specimen part
View SamplesIt has been reported that repeated intra-tracheal instillation of S. chartarum spores induced significant pulmonary arterial remodeling in mice, which resulted in pathological changes like human pulmonary arterial hypertension (PAH) and elevation right ventricle systolic pressure.
Gene expression analysis of a murine model with pulmonary vascular remodeling compared to end-stage IPAH lungs.
Sex, Specimen part, Disease, Disease stage
View SamplesOur previous investigation indicated that high-virulence C. gattii (C. gattii TIMM 4097) tend to reside in the alveoli, whereas low-virulence C. gattii (C. gattii TIMM 4903) tend to be washed out from the alveoli and move into the central side of the respiratory system. To test this hypothesis, we performed microarray assay.
How histopathology can contribute to an understanding of defense mechanisms against cryptococci.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Intestinal master transcription factor CDX2 controls chromatin access for partner transcription factor binding.
Specimen part
View SamplesA congenic mouse line was constructed by introgressing a C3H chromosome 9 region harboring Ath29 into the C57BL/6 apoE-deficient background. RNA was extracted from aorta using a QIAGEN kit . Total RNA was pooled in an equal amount from 3 mice for each group. Standard Affymetrix procedures were performed using 8ug of total RNA.
Characterization of Ath29, a major mouse atherosclerosis susceptibility locus, and identification of Rcn2 as a novel regulator of cytokine expression.
Disease, Disease stage
View SamplesCell differentiation requires epigenetic modulation of tissue-specific genes and activities of master transcriptional regulators, which are recognized for their dominant control over cellular programs. Using novel epigenomic methods, we characterized enhancer elements specifically modified in differentiating intestinal epithelial cells and found enrichment of transcription factor-binding motifs corresponding to CDX2, a master regulator of the intestine. Directed investigation revealed surprising lability in CDX2 occupancy of the genome, with redistribution from hundreds of sites occupied only in progenitors to thousands of new sites in mature cells. Knockout mice confirmed distinct Cdx2 requirements in dividing and differentiated adult intestinal cells, including responsibility for the active enhancer configuration associated with maturity. Dynamic CDX2 occupancy corresponds with condition-specific gene expression and, importantly, to differential co-occupancy with other tissue-restricted transcription factors: HNF4A in mature cells and GATA6 in progenitors. These results reveal dynamic, context-specific functions and mechanisms of a master transcription factor within a cell lineage.
Differentiation-specific histone modifications reveal dynamic chromatin interactions and partners for the intestinal transcription factor CDX2.
Specimen part, Cell line
View SamplesHistone H3 lysine 9 (H3K9) methylation is an epigenetic mark of transcriptionally repressed chromatin. During mammalian development, H3K9 methylation levels seem to be spatiotemporally regulated by the opposing activities of methyltransferases and demethylases to govern correct gene expression. However, the combination(s) of H3K9 methyltransferase(s) and demethylase(s) that contribute to this regulation and the genes regulated by them remain unclear. Herein, we demonstrate the essential roles of H3K9 demethylases Jmjd1a and Jmjd1b in the embryogenesis and viability control of embryonic stem (ES) cells. Mouse embryos lacking Jmjd1a/Jmjd1b died after implantation. Depletion of Jmjd1a/Jmjd1b in mouse ES cells induced rapid cell death accompanied with a massive increase in H3K9 methylation. Jmjd1a/Jmjd1b depletion induced an increase in H3K9 methylation in the gene-rich regions of the chromosomes, indicating that Jmjd1a/Jmjd1b removes H3K9 methylation marks in the euchromatin. Importantly, the additional disruption of the H3K9 methyltransferase G9a in a Jmjd1a/Jmjd1b-deficient background rescued not only the H3K9 hypermethylation phenotype but also the cell death phenotype. We also found that Jmjd1a/Jmjd1b removes H3K9 methylation marks deposited by G9a in the Oct4 and Ccnd1 loci to activate transcription. In conclusion, Jmjd1a/Jmjd1b ensures ES cell viability by antagonizing G9a-mediated H3K9 hypermethylation in the gene-rich euchromatin.
Combined Loss of JMJD1A and JMJD1B Reveals Critical Roles for H3K9 Demethylation in the Maintenance of Embryonic Stem Cells and Early Embryogenesis.
Specimen part
View Samples