Project description:To understand the mechanisms through which JunB regulates Tregs-mediated immune regulation, we examined the global gene expression profiles in the JunB WT and KO Tregs by performing RNA sequencing (RNA-seq) analysis.
Project description:Oxidative stress is pathogenic in neurological diseases including stroke. The identity of oxidative stress-inducible transcription factors and their role(s) in propagating the death cascade are poorly understood. Microarray analysis of neurons undergoing oxidative stress showed significant induction of prodeath genes. These genes have been shown to be regulated by the bZip transcription factor, ATF4. ATF4 protein localized to the promoter of a putative death gene in neurons in vitro and in vivo. Germline deletion of ATF4 in neurons resulted in a reduction in oxidative stress-induced gene expression and resistance to oxidative death. ATF4 knockout mice experienced significantly smaller infarcts and improved behavioral recovery as compared to wild-type mice subjected to the same reductions in blood flow in a rodent model of stroke. ATF4 modulates an early, upstream event in the death pathway, as resistance to oxidative death by ATF4 deletion was associated with decreased consumption of the antioxidant glutathione. Restoration of ATF4 protein in knockout neurons was sufficient to restore sensitivity to oxidative death and to reaccelerate loss of glutathione. Together, these findings establish ATF4 as a redox-regulated, pro-death transcriptional activator in the nervous system that propagates death responses to oxidative stress in vitro and to stroke in vivo. Keywords: ATF4, oxidative stress, gene expression, neuroprotection, stroke WT and ATF4 KO embryonic neurons were studied. Untreated neurons (no=8 per genotype) and neurons challenged with oxidative stress with the glutamate homolog homocysteate (HCA, no=4 per genotype) were studied, for a total of 24 samples.
Project description:Activating Transcription Factor 4 (ATF4) is a transcription factor induced by the integrated stress response (ISR). This experiment is a genome-wide profiling of ATF4-dependent RNA expression in human HAP-1 cells. HAP-1 is a near-haploid human cell line that was derived from KBM-7 cells isolated from a patient with Chronic Myelogenous Leukemia. We analyzed WT and ATF4 KO cells. We induced ATF4 expression by mimicking amino acid starvation with the drug histidinol. RNA expression profiles were generated for WT and ATF4 KO HAP1 cells. ATF4 genes were mutated using Cas9 genome editing technology. Amino acid starvation was mimicked by treating WT and ATF4 KO cells with 2 mM histidinol for 24 hours, which increases ATF4 expression.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.