ABSTRACT: A gene co-expression network analysis has been conducted to identify T2D-associated gene modules. Donors 1-48 were used for the initial analysis and donors 49-80 for the replication and were normalized separately in this study Islets from cadaver donors (57 non-diabetic and 20 diabetic) 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:Close to 50 genetic loci have been associated with type 2 diabetes (T2D), but they explain only 15% of the heritability. In an attempt to identify additional T2D genes, we analyzed global gene expression in human islets from 63 donors. Islets from cadaver donors (54 non-diabetic and 9 diabetic) 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:Expression profiling of cell cycle genes in human pancreatic islets with and without type 2 diabetes 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 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:Pancreatic islets are central in type 2-diabetes development, which coincides with increased activity of innate immunity. Intriguingly, human pancreatic islets express many complement genes. The most highly expressed gene was the complement inhibitor CD59 that is GPI anchored to the cell membrane, which unexpectedly was found in high amounts intracellularly in beta cells. Silencing of CD59 strongly suppressed insulin secretion. Importantly, this suppression was unrelated to established CD59 functions, but rather depletion of intracellular CD59. Imaging experiments identified a distal site of inhibition in the exocytotic pathway, but prior to emptying of the insulin granules. Proximity Ligation Assays pin-pointed the mechanism to impaired turnover of exocytosis-regulating SNARE-proteins and CD59 was detected in complex with VAMP2 and syntaxin. CD59 was downregulated by 24-h glucose incubations in human islets, rat cell lines and in islets from three rodent diabetes models. 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:In Arabidopsis thaliana, four different DICER-LIKE (DCL) proteins have distinct, but partially overlapping functions in the biogenesis of microRNAs (miRNAs) and small interfering RNAs (siRNAs) from longer, non-coding precursor RNAs. To analyze the impact of different components of the small RNA (sRNA) biogenesis machinery on the transcriptome, we subjected dcl and other mutants impaired in sRNA biogenesis to whole-genome tiling array analysis. We compared both protein-coding genes and noncoding transcripts, including most pri-miRNAs, in two tissues and several stress conditions. We discovered distinct effects of dcl1, hyl1 and se mutations on the transcriptome, as well as a number of common genes affected in dcl1 and dcl2 dcl3 dcl4 triple mutants. Our results furthermore suggest that the DCL1 is not only involved in miRNA action, but can also contribute to silencing of certain transposons, apparently through an effect on DNA methylation. Together, our findings contribute to the knowledge of both specialization and overlap between different RNA silencing pathways. Wild type and dcl1-100, se-3, hyl1-2, rdr6-15 ans dcl2,3,4 mutants were grown on MS or soil at 23M-BM-0C and LL. 7 day old seedlings (grown on MS plates) and inflorescences from 28 (>40) day old plants (dcl1) were used for RNA extraction. For stress treatments, seedlings had been grown for 10 days on solid MS medium at 21M-BM-0C, they were transferred to liquid MS medium containing no additives (mock control), 200 mM NaCl (salt stress), 300 mM mannitol (osmotic stress) or 100 M-NM-<M ABA. For cold and heat stress, seedlings were transferred to pre-chilled or pre-warmed liquid MS medium and incubated at 8M-BM-0C and 30M-BM-0C, respectively. Samples were taken after 1 h and 12 h of continuous stress treatment. RNA was extracted from whole seedlings. All RNA samples were converted into double stranded DNA targets that were hybridized to whole genome tiling arrays (Affymetrix Arabidopis Tiling1.0RM-BM-.). All hybridizations were performed with 3 biological replicates.
Project description:A major effort is underway to study the natural variation within the model plant species, Arabidopsis thaliana. Much of this effort is focused on genome resequencing, however the translation of genotype to phenotype will be largely effected through variations within the transcriptomes at the sequence and expression levels. To examine the cross-talk between natural variation in genomes and transcriptomes, we have examined the transcriptomes of three divergent A. thaliana accessions using tiling arrays. Combined with genome resequencing efforts, we were able to adjust the tiling array datasets to account for polymorphisms between the accessions and therefore gain a more accurate comparison of the transcriptomes. The corrected results for the transcriptomes allowed us to correlate higher gene polymorphism with greater variation in transcript level among the accessions. Our results demonstrate the utility of combining genomic data with tiling arrays to assay non-reference accession transcriptomes. Wild type accessions Col-0 were grown on soil at 16M-BM-0C with a 16 hour light period. Inflorescence tissue up to floral stage 14 was used for RNA extraction. Samples were collected 7-8 hours into the light period, with tissue from five plants pooled for each sample. RNA samples were converted into double stranded and hybridized to whole genome tiling arrays (Affymetrix Arabidopis Tiling1.0RM-BM-.). Three biological replicates were performed for each accession.
Project description:Dynamic changes in the mouse liver DNA methylome associated with short (1 day) and prolonged (7, 28 and 91 days) exposure to the rodent liver non-genotoxic carcinogen (NGC), phenobarbital (PB). Full expression dataset (all time points: 1, 7, 28, 91 days) Replicated control vs. pb treated study
Project description:A major effort is underway to study the natural variation within the model plant species, Arabidopsis thaliana. Much of this effort is focused on genome resequencing, however the translation of genotype to phenotype will be largely effected through variations within the transcriptomes at the sequence and expression levels. To examine the cross-talk between natural variation in genomes and transcriptomes, we have examined the transcriptomes of three divergent A. thaliana accessions using tiling arrays. Combined with genome resequencing efforts, we were able to adjust the tiling array datasets to account for polymorphisms between the accessions and therefore gain a more accurate comparison of the transcriptomes. The corrected results for the transcriptomes allowed us to correlate higher gene polymorphism with greater variation in transcript level among the accessions. Our results demonstrate the utility of combining genomic data with tiling arrays to assay non-reference accession transcriptomes. Wild type accessions Col-0, Bur-0 and C24 were grown on soil at 23M-BM-0C with a 16 hour light period. Inflorescence tissue up to floral stage 14 was used for RNA extraction. Samples were collected 7-8 hours into the light period, with tissue from five plants pooled for each sample. RNA samples were converted into double stranded and hybridized to whole genome tiling arrays (Affymetrix Arabidopis Tiling1.0RM-BM-.). Three biological replicates were performed for each accession.