Project description:Type 1 diabetes is an autoimmune destruction of pancreatic islet beta cell disease, and it is important to find new alternative source of the islet beta cells to replace the damaged cells. Human embryonic stem (hES) cells possess unlimited self-renewal and pluripotency and thus have the potential to provide an unlimited supply of different cell types for tissue replacement. The hES-T3 cells with normal female karyotype were first differentiated into embryoid bodies and then induced to generate the pancreatic islet-like cell clusters, which expressed pancreatic islet cell-specific markers of insulin, glucagon and somatostatin. The expression profiles of microRNAs and mRNAs from the pancreatic islet-like cell clusters were further analyzed and compared with those of undifferentiated hES-T3 cells and differentiated embryoid bodies. MicroRNAs negatively regulate the expression of protein-coding mRNAs. The pancreatic islet-like cell clusters were found to exhibit very high expression of microRNAs miR-186, miR-199a and miR-339, which down-regulated the expression of LIN28, PRDM1, CALB1, GCNT2, RBM47, PLEKHH1, RBPMS2 and PAK6. Therefore, these microRNAs are very likely to play important regulatory roles in the differentiation of pancreatic islet cells and early embryonic development. In this investigation, both miRNA and mRNA expression profiles from the pancreatic islet-like cell clusters differentiated from hES-T3 cells (T3pi) were quantitatively determined and compared with those of undifferentiated hES-T3 cells grown on mouse embryonic fibroblast (MEF) feeder (T3ES) and embryoid bodies differentiated from hES-T3 cells (T3EB). Several target genes of pancreatic islet cell-specific miRNAs were identified. ***This submission represents the mRNA expression component of the study only***
Project description:Type 1 diabetes is an autoimmune destruction of pancreatic islet beta cell disease, and it is important to find new alternative source of the islet beta cells to replace the damaged cells. Human embryonic stem (hES) cells possess unlimited self-renewal and pluripotency and thus have the potential to provide an unlimited supply of different cell types for tissue replacement. The hES-T3 cells with normal female karyotype were first differentiated into embryoid bodies and then induced to generate the pancreatic islet-like cell clusters, which expressed pancreatic islet cell-specific markers of insulin, glucagon and somatostatin. The expression profiles of microRNAs and mRNAs from the pancreatic islet-like cell clusters were further analyzed and compared with those of undifferentiated hES-T3 cells and differentiated embryoid bodies. MicroRNAs negatively regulate the expression of protein-coding mRNAs. The pancreatic islet-like cell clusters were found to exhibit very high expression of microRNAs miR-186, miR-199a and miR-339, which down-regulated the expression of LIN28, PRDM1, CALB1, GCNT2, RBM47, PLEKHH1, RBPMS2 and PAK6. Therefore, these microRNAs are very likely to play important regulatory roles in the differentiation of pancreatic islet cells and early embryonic development.
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:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Recent advances in the understanding of the genetics of type 2 diabetes (T2D) susceptibility have focused attention on the regulation of transcriptional activity within the pancreatic beta-cell. MicroRNAs (miRNAs) represent an important component of regulatory control, and have proven roles in the development of human disease and control of glucose homeostasis. We set out to establish the miRNA profile of human pancreatic islets and of enriched beta-cell populations, and to explore their potential involvement in T2D susceptibility. We used Illumina small RNA sequencing to profile the miRNA fraction in three preparations each of primary human islets and of enriched beta-cells generated by fluorescence-activated cell sorting. In total, 366 miRNAs were found to be expressed (i.e. >100 cumulative reads) in islets and 346 in beta-cells; of the total of 384 unique miRNAs, 328 were shared. A comparison of the islet-cell miRNA profile with those of 15 other human tissues identified 40 miRNAs predominantly expressed (i.e. >50% of all reads seen across the tissues) in islets. Several highly-expressed islet miRNAs, such as miR-375, have established roles in the regulation of islet function, but others (e.g. miR-27b-3p, miR-192-5p) have not previously been described in the context of islet biology. As a first step towards exploring the role of islet-expressed miRNAs and their predicted mRNA targets in T2D pathogenesis, we looked at published T2D association signals across these sites. We found evidence that predicted mRNA targets of islet-expressed miRNAs were globally enriched for signals of T2D association (p-values <0.01, q-values <0.1). At six loci with genome-wide evidence for T2D association (AP3S2, KCNK16, NOTCH2, SCL30A8, VPS26A, and WFS1) predicted mRNA target sites for islet-expressed miRNAs overlapped potentially causal variants. In conclusion, we have described the miRNA profile of human islets and beta-cells and provide evidence linking islet miRNAs to T2D pathogenesis. Examination of the miRNA profiles in 3 preparations of isolated pancreatic islets and 3 preparations of FACS-enriched pancreatic beta-cells