We adopted a transcriptome-wide microarray analysis approach to determine the extent to which vascular gene expression is altered as a result of juvenile obesity and identify obesity-responsive mRNAs. We examined transcriptional profiles in the left anterior descending coronary artery (LAD), perivascular fat adjacent to the LAD, and descending thoracic aorta between obese (n=5) and lean (n=6) juvenile Ossabaw pigs (age=22 weeks). Obesity was experimentally induced by feeding the animals a high-fat/high fructose corn syrup/high-cholesterol diet for 16 weeks. We found that expression of 189 vascular cell genes in the LAD and expression of 165 genes in the thoracic aorta were altered with juvenile obesity (FDR10%) with an overlap of only 28 genes between both arteries. Notably, a number of genes found to be markedly up-regulated in the LAD of obese pigs are implicated in atherosclerosis, including ACP5, LYZ, CXCL14, APOE, PLA2G7, LGALS3, SPP1, ITGB2, CYBB, and P2RY12. Furthermore, pathway analysis revealed the induction of pro-inflammatory and pro-oxidant pathways with obesity primarily in the LAD. Gene expression in the LAD perivascular fat was minimally altered with juvenile obesity. Together, we provide new evidence that obesity produces artery-specific changes in pre-translational regulation with a clear up-regulation of pro-atherogenic genes in the LAD. Our data may offer potential viable drug targets and mechanistic insights regarding the molecular precursors involved in the origins of over-nutrition and obesity-associated vascular disease. In particular, our results suggest that the oxLDL-LOX-1-NFB signaling axis may be involved in the early initiation of a juvenile obesity-induced pro-atherogenic coronary artery phenotype.
Vascular transcriptional alterations produced by juvenile obesity in Ossabaw swine.
Specimen part
View SamplesGene expression microarrays have made a profound impact in biomedical research. The diversity of platforms and analytical methods has made comparison of data from multiple platforms very challenging. In this study, we describe a framework for comparisons across platforms and laboratories. We have attempted to include nearly all the available commercial and in house platforms. Using probe sequences matched at the exon level improved consistency of measurements across the different microarray platforms compared to annotation-based matches. Generally, consistency was good for highly expressed genes, and variable for genes with lower expression values as confirmed by QRT-PCR. Concordance of measurements was higher between laboratories on the same platform than across platforms. We demonstrate that, after stringent pre-processing, commercial arrays were more consistent than in-house arrays, and by most measures, one-dye platforms were more consistent than two-dye platforms.
A sequence-oriented comparison of gene expression measurements across different hybridization-based technologies.
No sample metadata fields
View SamplesGene expression microarrays have made a profound impact in biomedical research. The diversity of platforms and analytical methods has made comparison of data from multiple platforms very challenging. In this study, we describe a framework for comparisons across platforms and laboratories. We have attempted to include nearly all the available commercial and in-house platforms. Using probe sequences matched at the exon level improved consistency of measurements across the different microarray platforms compared to annotation-based matches. Generally, consistency was good for highly expressed genes, and variable for genes with lower expression values as confirmed by QRT-PCR. Concordance of measurements was higher between laboratories on the same platform than across platforms. We demonstrate that, after stringent pre-processing, commercial arrays were more consistent than in-house arrays, and by most measures, one-dye platforms were more consistent than two-dye platforms.
A sequence-oriented comparison of gene expression measurements across different hybridization-based technologies.
No sample metadata fields
View SamplesWorms that inherited the sperm genome lacking the repressive mark H3K27me3 (K27me3 M+P-) misexpress genes in their germlines when compared to genetically identitical worms that inherited the sperm genome with H3K27me3 (K27me3 M+P+). Overall design: Transcriptome profiles of hermaphrodite germlines from hybrid worms that inherited the sperm genome with H3K27me3 (4 replicates of K27me3 M+P+) vs without H3K27me3 (4 replicates K27me3 M+P-) to compare to 4 replicates of 'wildtype'.
Sperm-inherited H3K27me3 impacts offspring transcription and development in C. elegans.
Specimen part, Cell line, Subject
View SamplesThe germ lineage is considered to be immortal. In the quest to extend lifespan, a possible strategy is to drive germline traits in somatic cells, to try to confer some of the germ lineage’s immortality on the somatic body. Notably, a study in C. elegans suggested that expression of germline genes in the somatic cells of long-lived daf-2 mutants confers some of daf-2’s longevity. Specifically, mRNAs encoding components of C. elegans germ granules (P granules) were up-regulated in daf-2 mutant worms, and knock-down of individual P-granule and other germline genes in daf-2 young adults modestly reduced their lifespan. We investigated the contribution of a germline program to daf-2’s long lifespan, and also tested if other mutants known to express germline genes in their somatic cells are long-lived. Our key findings are: 1) We could not detect P-granule proteins in the somatic cells of daf-2 mutants by immunostaining or by expression of a P-granule transgene. 2) Whole-genome transcript profiling of animals lacking a germline revealed that germline transcripts are not up-regulated in the soma of daf-2 worms compared to the soma of control worms. 3) Simultaneous removal of multiple P-granule proteins or the entire germline program from daf-2 worms did not reduce their lifespan. 4) Several mutants that robustly express a broad spectrum of germline genes in their somatic cells are not long-lived. Taken together, our findings argue against the hypothesis that acquisition of a germ cell program in somatic cells increases lifespan and contributes to daf-2’s longevity. Overall design: Transcriptome profiles of 3 replicates of sterile daf-2; mes-1 double mutants (experimental) and 3 replicates of sterile mes-1 single mutants (control) grown at 24°C
Reevaluation of whether a soma-to-germ-line transformation extends lifespan in Caenorhabditis elegans.
Cell line, Subject
View SamplesHere we uncover antagonistic regulation of transcript levels in the germline of Caenorhabditis elegans hermaphrodites. The histone methyltransferase MES-4 marks genes expressed in the germline with methylated Lys36 on histone H3 (H3K36me) and promotes their transcription; MES-4 also represses genes normally expressed in somatic cells and genes on the X chromosomes. The DRM complex, which includes E2F/DP and Retinoblastoma homologs, affects germline gene expression and prevents excessive repression of X-chromosome genes. Using genome-scale analyses of germline tissue, we show that common germline-expressed genes are activated by MES-4 and repressed by DRM, and that MES-4 and DRM co-bind many germline-expressed genes. Reciprocally, MES-4 represses and DRM activates a set of autosomal soma-expressed genes and overall X-chromosome gene expression. Mutations in mes-4 or the DRM subunit lin-54 oppositely skew target transcript levels and cause sterility; a double mutant restores near wild-type transcript levels and germ cell development. Together, yin-yang regulation by MES-4 and DRM ensures transcript levels appropriate for germ cell function, elicits robust but not excessive dampening of X-chromosome-wide transcription, and may poise genes for future expression changes. Our study reveals that conserved transcriptional regulators implicated in development and cancer counteract each other to fine-tune transcript dosage.
Opposing activities of DRM and MES-4 tune gene expression and X-chromosome repression in Caenorhabditis elegans germ cells.
Sex
View SamplesNeedle biopsies were obtained from the vastus lateralis muscle of 6 healthy, sedentary, 672.5 year-old males before and after 3 months of training.
Effects of aerobic training on gene expression in skeletal muscle of elderly men.
No sample metadata fields
View SamplesApoptosis is a controlled cell-death process mediated inter alia by proteins of the Bcl-2 family. Some proteins previously shown to promote the apoptotic process were found to have non-apoptotic functions as well. Microglia, the resident immune cells of the central nervous system, respond to brain derangements by becoming activated to contend with the brain damage. Activated microglia can also undergo activation-induced cell death. Previous studies have addressed the role of core apoptotic proteins in the death process, but whether or not these proteins also play a role in the activation process has not been reported. Here we explore the effect of the BH3-only protein Bid on the immunological features of microglia by subjecting both WT and Bid deficient primary neonatal microglial cultures to LPS treatment (100 ng/ml, 3h) or left untreated (control) and analyzing their transcription profiles in order to study the role of Bid.
Bid regulates the immunological profile of murine microglia and macrophages.
Specimen part
View SamplesWe explored mechanisms of carcinogenicity of acrylamide in the rat thyroid. We compared the transcriptome profiles of target(thyroid) vs non-target(liver) tissues.
Transcriptional profiling of male F344 rats suggests the involvement of calcium signaling in the mode of action of acrylamide-induced thyroid cancer.
No sample metadata fields
View SamplesComparison of syncytia gene expression between soybean near-isogenic lines 7923R (NIL-R) and 7923S (NIL-S) infected with the soybean cyst nematode (PA3).
The Soybean Rhg1 locus for resistance to the soybean cyst nematode Heterodera glycines regulates the expression of a large number of stress- and defense-related genes in degenerating feeding cells.
Specimen part
View Samples