Project description:ARID1A is a tumor suppressor gene mutated in 7-10% of pancreatic cancer patients. However, its function in pancreas development and endocrine regulation is unclear. We generated mice that lack Arid1a expression in the pancreas. Our results showed that deletion of the Arid1a gene in mice caused a reduction in islet numbers and insulin production, both of which are associated with diabetes mellitus (DM) phenotype.we performed chromatin immunoprecipitation-sequencing analysis (ChIP-seq) to study genome-wide HDAC6 occupancy in the control and Arid1a-depleted islet cells.
Project description:Macrophages residing within mouse pancreatic islets display an activated phenotype at steady state, yet the molecular signatures underlying their polarization remain unclear. To investigate islet macrophage heterogeneity under physiological conditions, we isolated islet-resident immune cells from chow diet-fed adult male mice and performed single-cell RNA sequencing.
Project description:The islet is composed of diverse cell types that work together to regulate its endocrine function. To investigate this, we performed comparative single-cell RNA sequencing (scRNA-seq) on islets from 16-week-old βZKO-Mip, βZKO-Rip, RIP-Cre, and MIP-Cre mice, all of which were fed a high-fat diet (HFD) from 12 to 16 weeks. Sequencing was carried out using the Chromium Next GEM Single Cell 3' Reagent Kits. Each islet sample was derived from at least three mice with the same genotype.
Project description:Single-cell sequencing of islet cells from WT , ASF knock-out, SC35 knock-out mice reveals different mechanisms of diabetes formation and development.
Project description:Single-cell RNA sequencing of pancreatic islets from adult male mice. To disect islet heterogeneity we sorted cells based on anatomical location and maturity marker (Fltp).
Project description:To get a more complete picture of the transcriptional changes associated with Pdx1 loss in ?-cells, we conducted an mRNA microarray comparing normal islet ?-cells and a-cells to the reprogrammed cells from PKO mice. Islet beta cells are from mice which has a single copy of Pdx1 flox (Pdx1L/+) allele, but is considered normal based on normal islet morphology, gene profiling, and euglycemic status. We chose to use heterozygous mice as control to avoid the litter effect. Islet alpha cells are from normal mice. To enrich for genes directly affected by Pdx1 loss, we chose the early time-point for analysis of PKO mice (5d after TAM administration). Control mRNA profiling was performed on FACS sorted islet YFP+ ?-cells and a-cells obtained from 2 month-old glucagon-Cre; RosaYFP and RIP-CreER; Pdx1fl/+, RosaYFP mice, respectively.
Project description:Chromatin-based functional genomic analyses and genomewide association studies (GWASs) together implicate enhancers as critical elements influencing gene expression and risk for common diseases. Here, we performed systematic chromatin and transcriptome pro- filing in human pancreatic islets. Integrated analysis of islet data with those generated by the ENCODE project in nine cell types identified specific and significant enrichment of type 2 diabetes and related quantitative trait GWAS variants in islet enhancers. Our integrated chromatin maps reveal that most enhancers are short (median = 0.8 kb). Each cell type also contains a substantial number of more extended (≥3 kb) enhancers. Interestingly, these stretch enhancers are often tissue-specific and overlap locus control regions, suggesting that they are important chromatin regulatory beacons. Indeed, we show that (i) tissue specificity of enhancers and nearby gene expression increase with enhancer length; (ii) neighborhoods containing stretch enhancers are enriched for important cell type– specific genes; and (iii) GWAS variants associated with traits rele- vant to a particular cell type are more enriched in stretch enhancers compared with short enhancers. Reporter constructs containing stretch enhancer sequences exhibited tissue-specific activity in cell culture experiments and in transgenic mice. These results suggest that stretch enhancers are critical chromatin elements for coordinating cell type–specific regulatory programs and that sequence variation in stretch enhancers affects risk of major common human diseases. Integrated analysis of islet chromatin modification and transcriptome data with those generated by the ENCODE project. NISC Comparative Sequencing Program