Microarrays were used to detail the global programme of gene expression comparing wild-type and RNAi knock-down plants of SPT4-1 and SPT4-2
The transcript elongation factor SPT4/SPT5 is involved in auxin-related gene expression in Arabidopsis.
Age, Specimen part
View SamplesThe identification of multiple signals at individual loci could explain additional phenotypic variance ('missing heritability') of common traits, and help identify causal genes. We examined gene expression levels as a model trait because of the large number of strong genetic effects acting in cis. Using expression profiles from 613 individuals, we performed genome-wide single nucleotide polymorphism (SNP) analyses to identify cis-expression quantitative trait loci (eQTLs), and conditional analysis to identify second signals. We examined patterns of association when accounting for multiple SNPs at a locus and when including additional SNPs from the 1000 Genomes Project. We identified 1298 cis-eQTLs at an approximate false discovery rate 0.01, of which 118 (9%) showed evidence of a second independent signal. For this subset of 118 traits, accounting for two signals resulted in an average 31% increase in phenotypic variance explained (Wilcoxon P< 0.0001). The association of SNPs with cis gene expression could increase, stay similar or decrease in significance when accounting for linkage disequilibrium with second signals at the same locus. Pairs of SNPs increasing in significance tended to have gene expression increasing alleles on opposite haplotypes, whereas pairs of SNPs decreasing in significance tended to have gene expression increasing alleles on the same haplotypes. Adding data from the 1000 Genomes Project showed that apparently independent signals could be potentially explained by a single association signal. Our results show that accounting for multiple variants at a locus will increase the variance explained in a substantial fraction of loci, but that allelic heterogeneity will be difficult to define without resequencing loci and functional work.
Allelic heterogeneity and more detailed analyses of known loci explain additional phenotypic variation and reveal complex patterns of association.
Specimen part
View SamplesWe exploited microarrays to detail the global program of gene expression underlying normal stem cells and cancer stem cells in the cerebellum and in medulloblastomas (MBs).
Gene signatures associated with mouse postnatal hindbrain neural stem cells and medulloblastoma cancer stem cells identify novel molecular mediators and predict human medulloblastoma molecular classification.
Specimen part
View SamplesInflammatory mediators play a role in the pathogenesis/progression of chronic heart failure (CHF). The aim of the present study was to identify diagnostic/prognostic markers and gene expression profiles of CHF vs control.
Gene expression profiles in peripheral blood mononuclear cells of chronic heart failure patients.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cancer exosomes perform cell-independent microRNA biogenesis and promote tumorigenesis.
Specimen part, Cell line
View SamplesHuman lymphoid tissues harbor, in addition to CD56bright and CD56dim natural killer (NK) cells, a third NK cell population: CD69+CXCR6+ lymphoid tissue (lt)NK cells. The function and development of ltNK cells remain poorly understood. In this study we performed RNA sequencing on the CD56bright and CD56dim NK cells (from bone marrow and blood), and the ltNK cells (from bone marrow). In addition, the blood derived CD56dim, and bone marrow derived ltNK cells were further subdivided into a NKG2A+ and NKG2A- fraction. Paired blood and bone marrow samples of 4 healthy donors were included. When comparing the NKG2A fractions, only 3 genes (of 9382 genes included) had a significantly differential expression. Therefore, we pooled the expression data proportionally from the NKG2A+ and NKG2A- fractions in subsequent analyses. In ltNK cells, 1353 genes were differentially expressed compared to circulating NK cells. Several molecules involved in migration were downregulated in ltNK cells: S1PR1, SELPLG and CD62L. By flow cytometry we confirmed that the expression profile of adhesion molecules (CD49e-, CD29low, CD81high, CD62L-, CD11c-) and transcription factors (Eomeshigh, Tbetlow) of ltNK cells differed from their circulating counterparts. LtNK cells were characterized by enhanced expression of inhibitory receptors TIGIT and CD96 and low expression of DNAM1 and cytolytic molecules (GZMB, GZMH, GNLY). Their proliferative capacity was reduced compared to the circulating NK cells. By performing gene set enrichment analysis we identified DUSP6 and EGR2 as potential regulators of the ltNK cell transcriptome. Remarkably, comparison of the ltNK cell transcriptome to the published human spleen-resident memory CD8+ T (Trm) cell transcriptome revealed an overlapping gene signature. Moreover, the phenotypic profile of ltNK cells resembled that of CD8+ Trm cells in bone marrow. Together, we provide a comprehensive molecular framework of the conventional CD56bright and CD56dim NK cells as well as the tissue-resident ltNK cells and provide a core gene signature which might be involved in promoting tissue-residency. Overall design: mRNA sequencing of NK cell populations isolated from blood: CD56bright, NKG2A+ CD56dim and NKG2A- CD56dim, and bone marrow: CD56bright, CD56dim, NKG2A+ ltNK, and NKG2A- ltNK. Each sample has 4 biological replicates.
Human Bone Marrow-Resident Natural Killer Cells Have a Unique Transcriptional Profile and Resemble Resident Memory CD8<sup>+</sup> T Cells.
Specimen part, Subject
View SamplesEffect of the overexpression of the oncogenic form of the Vav2 protein in the NIH3T3 cell line under serum deprivation conditions. oncovav2-transformed NIH3T3 cells grown in serum-deprived medium (Vav2SD) are compared to the parental NIH3T3 controls under the same growth conditions (ContSD). Vav2SD cells are also compared to the oncovav2-transformed NIH3T3 cells growing exponentially and the NIH3T3 growing exponentially.
Microarray analysis of gene expression with age in individual nematodes.
Cell line
View SamplesDrosophila males double transcription of their single X chromosome to equalize X-linked gene expression with females, which carry two X chromosomes. Increased transcription requires the Male-Specific Lethal (MSL) complex. One of the primary functions of the MSL complex is thought to be enrichment of H4Ac16 on the male X chromosome, a modification linked to elevated transcription. The roX1 and roX2 RNAs are essential but redundant components of the MSL complex. Simultaneous removal of both roX RNAs reduces MSL X-localization and leads to ectopic binding of these proteins at autosomal sites and to the chromocenter. Some H4Ac16 accumulates at these ectopic sites in roX1- roX2- males, suggesting the possibility of increased expression. The global effect of roX mutations on gene expression was measured by microarray analysis. We found that expression of the X chromosome was decreased by 26% in roX1- roX2- male larvae, supporting the involvement of roX RNAs in the up-regulation of X-linked genes. This finding is broadly comparable to reports of reduced X chromosome expression following msl2 RNAi knockdown in S2 cells. In spite of strong MSL binding and H4Ac16 accumulation at autosomal sites in roX1- roX2- males, enhanced gene expression could not be detected at these sites by microarray analysis or reverse northern blotting. Thus, failure to compensate X-linked genes, rather than inappropriate up-regulation of autosomal genes at ectopic sites of MSL binding, appears to cause male lethality upon loss of roX RNAs.
roX RNAs are required for increased expression of X-linked genes in Drosophila melanogaster males.
Sex
View Sampleslet-7c and miR-294 were transfected into Dgcr8 -/- miRNA deficient ES cells and RNA was harvested after 12 hours
Opposing microRNA families regulate self-renewal in mouse embryonic stem cells.
Specimen part
View SamplesDicer, which is required for the processing of both microRNAs (miRNAs) and small interfering RNAs (siRNAs), is essential for oocyte maturation. Oocytes express both miRNAs and endogenous siRNAs (endo-siRNAs). To determine whether the abnormalities in Dicer knockout oocytes during meiotic maturation are secondary to the loss of endo-siRNAs and/or miRNAs, we deleted Dgcr8, which encodes a RNA binding protein specifically required for miRNA processing. In striking contrast to Dicer, Dgcr8 deficient oocytes matured normally and, when fertilized with wild-type sperm, produced healthy appearing offspring, even though miRNA levels were reduced to similar levels as Dicer deficient oocytes. Furthermore, the deletion of both maternal and zygotic Dgcr8 alleles did not impair preimplantation development including the determination of the inner cell mass (ICM) and trophectoderm. Most surprisingly, the mRNA profiles of wild-type and Dgcr8 null oocytes were essentially identical while Dicer null oocytes showed hundreds of misregulated transcripts. These findings show that miRNA function is globally suppressed during oocyte maturation and preimplantation development and that endo-siRNAs, rather than miRNAs, underlie the Dicer knockout phenotype in oocytes.
Opposing microRNA families regulate self-renewal in mouse embryonic stem cells.
Specimen part
View Samples