Project description:Stimulus-specific gene expression programs are enabled by enhancers, on which stimulus-regulated transcription factors (SRTFs) can land in a cell type- and stimulus-dependent manner. In this study, we identified the key features of enhancers that mediate differential responses to Toll-like receptor (TLR)-stimulation. We characterized the TLR3- and TLR9-induced programs and enhancers in CD8+ dendritic cells.The relevance of these features has been confirmed via machine learning application and by mapping SRTF-binding.
Project description:Stimulus-specific gene expression programs are enabled by enhancers, on which stimulus-regulated transcription factors (SRTFs) can land in a cell type- and stimulus-dependent manner. In this study, we identified the key features of enhancers that mediate differential responses to Toll-like receptor (TLR)-stimulation. We characterized the TLR3- and TLR9-induced programs and enhancers in CD8+ dendritic cells.The relevance of these features has been confirmed via machine learning application and by mapping SRTF-binding.
Project description:Stimulus-specific gene expression programs are enabled by enhancers, on which stimulus-regulated transcription factors (SRTFs) can land in a cell type- and stimulus-dependent manner. In this study, we identified the key features of enhancers that mediate differential responses to Toll-like receptor (TLR)-stimulation. We characterized the TLR3- and TLR9-induced programs and enhancers in CD8+ dendritic cells.The relevance of these features has been confirmed via machine learning application and by mapping SRTF-binding.
Project description:We inflicted TBI to chemokine-deficient mouse lines in order to establish involvement of various signalling pathways that may be addressed therapeutically. Interacting chemokine pathways in brain regulate distinct inflammatory cells. Activated microglia are separate from invading phagocytes and dendritic cells. Findings show potential targets to interfere with specific inflammatory responses after brain injury.
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.
Project description:In mammals, retinal damage is followed by Müller glia cell activation and proliferation. While retinal gliosis persists in adult mammals after an insult or disease, some vertebrates, including zebrafish, have the capacity to regenerate. We believe we are the first group to show that gliosis is a fibrotic-like process in mammals’ eyes caused by differential activation of canonical and non-canonical TGFβ signaling pathways.
Project description:Toll like receptors (TLRs) sense microbial products and initiate adaptive immune responses by activating dendritic cells (DCs). Since pathogens may contain several agonists we asked whether different TLRs may synergize in DC activation. We report that in human and mouse DC TLR3 or TLR4 potently synergize with TLR7, TLR8 or TLR9 in the induction of selected cytokine genes. Upon synergistic stimulation, IL-12, IL-23 and Delta-4 are induced at levels 50-100 fold higher than those induced by optimal concentrations of single agonists, leading to enhanced and sustained TH1 polarizing capacity. Using microarray analysis we show that only 1.5% of the transcripts induced by single TLR agonists are synergistically regulated by combinations of TLR4 and TLR8 agonists.. These results identify a combinatorial code by which DCs discriminate pathogens and provide (suggest) a rationale to design adjuvants for TH1 responses. Series_overall_design: 3 untreated, 3 treated with LPS at 2h, 3 treated with LPS at 8h, 3 treated with R848 at 2h, 3 treated with R848 at 8h, 3 treated with LPS + R848 at 2h, 3 treated with LPS + R848 at 8h
Project description:To discover the key determinants of IRF-specific enhancer selection, we identified and characterized IRF binding regions. Using chromatin immunoprecipitation coupled with deep sequencing (ChIP-seq), we mapped the binding regions of IRF3, IRF5, and IRF9 in murine dendritic cells (DCs) stimulated with TLR3 and TLR9 agonists, as well as IFNβ, respectively. We comprehensively analysed the IRF cistromes to identify characteristic features, including DNA motifs for IRFs and other transcription factors, and chromatin status.