Project description:Here we harnessed the potential of RNA sequencing in 89 human pancreatic islet donors to identify genes and exons regulated in this relevant tissue for T2D. mRNA profiles of 89 human pancreatic islet donors having different levels of blood glucose (HbA1c) with and without T2D. The data was generated by deep sequencing using Illumina HiSeq 2000.
Project description:Here we harnessed the potential of expression arrays in 89 human pancreatic islet donors (different levels of blood glucose (HbA1c)) to identify genes regulated in this relevant tissue for type 2 diabetes (T2D). Islets from cadaver donors were provided by the Nordic Islet Transplantation Programme (www.nordicislets.org), Uppsala University. The microarrays were performed using GeneChipM-BM-. Human Gene 1.0 ST whole transcript according to Affymetrix standard protocol.
Project description:Here we harnessed the potential of RNA sequencing in 89 human pancreatic islet donors to identify genes and exons regulated in this relevant tissue for T2D.
Project description:Here we harnessed the potential of expression arrays in 89 human pancreatic islet donors (different levels of blood glucose (HbA1c)) to identify genes regulated in this relevant tissue for type 2 diabetes (T2D).
Project description:Mechanisms driving sex differences across islet cells is unknown. Thus, studying sex differences in islet regulation and function represent a unique avenue to understand the sex-specific heterogeneity in β cell failure in diabetes. We examined sex and race differences in human pancreatic islets from 15 donors using an orthogonal series of experiments including single cell RNA-seq (scRNA-seq), single nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq), dynamic hormone secretion, and bioenergetics.
Project description:We have studied the impact of T2D on open chromatin in human pancreatic islets. We used assay for transposase-accessible chromatin using sequencing (ATAC-seq) to profile open chromatin in islets from T2D and non-diabetic donors. We identified ATAC-seq peaks representing open chromatin regions in islets of non-diabetic and diabetic donors. The majority of ATAC-seq peaks mapped near transcription start sites. Additionally, peaks were enriched in enhancer regions and in regions where islet-specific TFs bind. Islet ATAC-seq peaks overlap with SNPs associated with T2D and with additional SNPs in LD with known T2D SNPs. There was enrichment of open chromatin regions near highly expressed genes in human islets.
Project description:Human pancreatic islets were isolated from pancreas of deceased donors by Ricordi's procedure and cultured in CMRL 1066 medium additioned with human albumin. EVs were isolated from conditioned medium derived from islet culture after isolation. Once isolated, RNA of islets and islet-derived EVs was extracted and analyzed for microRNA expression within 48 hours after isolation.
Project description:Mechanisms driving sex differences across islet cells is unknown. Thus, studying sex differences in islet regulation and function represent a unique avenue to understand the sex-specific heterogeneity in β cell failure in diabetes. We examined sex and race differences in human pancreatic islets from 15 donors using an orthogonal series of experiments including single cell RNA-seq (scRNA-seq), single nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq), dynamic hormone secretion, and bioenergetics.
Project description:Identifying cis-regulatory elements is important to understand how human pancreatic islets modulate gene expression in physiologic or pathophysiologic (e.g., diabetic) conditions. We conducted genome-wide analysis of DNase I hypersensitive sites, histone H3 lysine methylation marks (K4me1, K4me3, K79me2), and CCCTC factor (CTCF) binding in human islets. This identified ~18,000 putative promoters (several hundred novel and islet-active). Surprisingly, active promoter marks were absent at genes encoding islet-specific hormones, suggesting a distinct regulatory mechanism. Of 34,039 distal (non-promoter) regulatory elements, 47% are islet-unique and 22% are CTCF-bound. These findings present a global snapshot of the human islet epigenome and should provide functional context for non-coding variants emerging from genetic studies of T2D and other pancreatic islet disorders. Three different islet samples were tested for DNase I hypersensitivity by DNase-Seq. Five different primary pancreatic islet samples were evaluated for several chromatin modifications (H3K4me3, H3K4me1, H3K79me2) by ChIP-seq. One islet sample was evaluated for CTCF binding via ChIP-seq, All ChIP-seq samples have both non-specific IP (GFP) and input DNA controls.