Gene bodies of vertebrates and flowering plants are occupied by histone variant H3.3 and DNA methylation. The origin and significance of these profiles remain largely unknown. The profiles of enrichments in DNA methylation and H3.3 over gene bodies are correlated and both depend similarly on gene transcription levels. This suggests a mechanistic link between H3.3 and gene body methylation. We engineered H3.3 knockdown in Arabidopsis and observed transcription reduction that predominantly affected genes responsive to environmental cues. When H3.3 levels were reduced, gene bodies showed a loss of DNA methylation correlated with transcription levels. To study the origin of changes in DNA methylation profiles when H3.3 levels are reduced, we examined genome wide distributions of several histone H3 marks, H2A.Z, linker histone H1 and nucleosome densities. We observed that in absence of H3.3, H1 distribution increased in gene bodies. This depends on levels of gene transcription. We propose that H3.3 prevents recruitment of H1, which in turn promotes chromatin folding and antagonizes access to DNA methyltransferases responsible for gene body methylation. Thus, gene body methylation is likely shaped by H3.3 dynamics in relation with transcriptional activity. Overall design: Examination of transcription in WT and H3.3 knock down samples by RNA-Seq
The histone H3 variant H3.3 regulates gene body DNA methylation in Arabidopsis thaliana.
Subject
View SamplesCells that have been pre-exposed to mild stress (priming stress) acquire transient resistance to subsequent severe stress even under different combinations of stresses. This phenomenon is called cross-tolerance. Although it has been reported that cross-tolerance occurs in many organisms, the molecular basis is not clear yet. Here, we identified slm9+ as a responsible gene for the cross-tolerance in the fission yeast Schizosaccharomyces pombe. Slm9 is a homolog of mammalian HIRA histone chaperone. HIRA forms a conserved complex and gene disruption of other HIRA complex components, Hip1, Hip3, and Hip4, also yielded a cross-tolerance-defective phenotype, indicating that the fission yeast HIRA is involved in the cross-tolerance as a complex. We also revealed that Slm9 was recruited to the stress-responsive gene loci upon stress treatment in an Atf1-dependent manner. The expression of stress-responsive genes under stress conditions was compromised in HIRA disruptants. Consistent with this, Pol II recruitment and nucleosome eviction at these gene loci were impaired in slm9D cells. Furthermore, we found that the priming stress enhanced the expression of stress-responsive genes in wild-type cells that were exposed to the severe stress. These observations suggest that HIRA functions in stress response through transcriptional regulation.
HIRA, a conserved histone chaperone, plays an essential role in low-dose stress response via transcriptional stimulation in fission yeast.
No sample metadata fields
View SamplesBlood was extracted from embryonic hearts at E4 and E6 and non-red blood was separated by density gradient centrifugation
Expression profiling of circulating non-red blood cells in embryonic blood.
No sample metadata fields
View SamplesHumoral responses of mice specifically deleted for Moz (a histone acetyltransferase) or c-Myb (a transcription factor) in B cells were aberrant. RNA-sequencing analysis was performed to assess gene expression differences compared to wild-type controls in germinal center B cells or plasmablasts. Overall design: Moz f/f Aicda1-Cre, Aicda1-Cre, Myb f/f Cd23-Cre, Mybf/f (no cre) mice were immunized with NP-KLH precipitated in alum and germinal center B cells were sort-purified. Secondary plasmablasts were sort-purified from immunized mice boosted with NP-KLH in PBS (Myb experiment). Two independent experiments were conducted.
Regulation of germinal center responses and B-cell memory by the chromatin modifier MOZ.
Specimen part, Subject
View SamplesTo identify molecular pathophysiologic changes and novel disease mechanisms specific to myelomeningocele by analyzing AFS cfRNA in fetuses with open myelomeningocele.
Amniotic fluid transcriptomics reflects novel disease mechanisms in fetuses with myelomeningocele.
No sample metadata fields
View SamplesScreening for genes regulated by Etv2 within Flk-1+/PDGFRa+ ES derived mesoderm.Microarray analysis performed to screen for the candidate genes regulated by Etv2. TT2 ES cells differentiated on OP9 feeder cells were sorted using Flk-1 and PDGFRa antibodies.Gene expressions from these two populations were compared.
Etv2/ER71 induces vascular mesoderm from Flk1+PDGFRα+ primitive mesoderm.
Cell line
View SamplesScreening for genes up in Etv2+ cells within Flk-1+ ES derived mesoderm
Etv2/ER71 induces vascular mesoderm from Flk1+PDGFRα+ primitive mesoderm.
Cell line
View SamplesC.pn potentiated hyperlipidemia-induced inflammasome activity in cultured macrophages and in foam cells in atherosclerotic lesions of Ldlr/ mice. We discovered that C.pn-induced extracellular IL-1 triggers a negative feedback loop to inhibit GPR109a and ABCA1 expression and cholesterol efflux leading to accumulation of intracellular cholesterol and foam cell formation. Gpr109a and Abca1 were both upregulated in plaque lesions in Nlrp3/ mice in both hyperlipidemic and C.pn infection models.
Chlamydia pneumoniae Hijacks a Host Autoregulatory IL-1β Loop to Drive Foam Cell Formation and Accelerate Atherosclerosis.
Specimen part, Treatment
View SamplesThe counterregulatory response to hypoglycemia, which restores normal blood glucose levels to ensure sufficient provision of glucose to the brain, is critical for survival. To discover underlying brain regulatory systems, we performed a genetic screen in recombinant inbred mice for quantitative trait loci (QTL) controlling glucagon secretion in response to neuroglucopenia. We identified a QTL on the distal part of chromosome 7 and combined this genetic information with transcriptomic analysis of hypothalami. This revealed Fgf15 as the strongest candidate to control the glucagon response. Fgf15 was found to be expressed by neurons of the dorsomedial hypothalamus and the perifornical area. Intracerebroventricular injection of FGF19, the human ortholog of Fgf15, reduced activation by neuroglucopenia of dorsal vagal complex neurons and of the parasympathetic nerve, leading to a lower glucagon secretion. These data show that Fgf15 in hypothalamic neurons is a regulator of vagal nerve activity in response to neuroglucopenia. Overall design: 36 BXD strains + 4 parental strains, 1 time point, basal condition without treatment
A Genetic Screen Identifies Hypothalamic Fgf15 as a Regulator of Glucagon Secretion.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MAFG is a transcriptional repressor of bile acid synthesis and metabolism.
Treatment
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