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GSE3990
Drosophila melanogaster
6 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Drosophila 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.
Publication Title
roX RNAs are required for increased expression of X-linked genes in Drosophila melanogaster males.
Sample Metadata Fields
Sex
View Samples- Arabidopsis thaliana
- 40 Downloadable Samples
Illumina HiSeq 2000
Description
40 QC single cells multiplexed using the CEL-Seq protocol Overall design: 40 cells from the QC
Publication Title
Quantification of cell identity from single-cell gene expression profiles.
Sample Metadata Fields
Age, Subject
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
roX RNAs are involved in the chromosome-wide gene regulation that occurs during dosage compensation in Drosophila. Dosage compensation equalizes expression of X-linked and autosomal genes. Drosophila males increase transcription two-fold from their single X chromosome. This is mediated by the MSL complex, which is composed of the male-specific lethal (MSL) proteins and two noncoding roX RNAs, roX1 and roX2. Upon elimination of both roX transcripts, a global decrease of X-linked gene expression is observed in males. Expression of the genes on the entire 4th chromosome also decreased in the absence of both roX transcripts. roX1 RNA also presents in females in the early stages. To investigate the effect of loss of roX transcripts on gene expression in females, gene expression was analyzed by microarrays in roX1-roX2- female flies. To eliminate inconsistency caused by differences in genetic background, expression of roX1-roX2- females with females of virtually identical genetic background but carrying the [hsp83-roX1+] transgene were compared. Expression of any chromosome did not change in roX1-roX2- females. It was concluded that roX RNAs only effect in males .
Publication Title
Coordinated regulation of heterochromatic genes in Drosophila melanogaster males.
Sample Metadata Fields
Sex
View Samples- Arabidopsis thaliana
- 3 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
The Arabidopsis quiescent center (QC) is a small group of cells with low mitotic activity located at the center of the root stem cell niche. Its transcriptional profile was previously analyzed using two repeats of cells FACS isolated using the WOX5 marker.
Publication Title
Quantification of cell identity from single-cell gene expression profiles.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 2 Downloadable Samples
- Illumina Genome Analyzer II
Description
miRNAs are small non-coding RNAs that inhibit translation and promote mRNA decay. The levels of mature miRNAs are the result of different rates of transcription, processing, and turnover. The non-canonical polymerase Gld2 has been implicated in the stabilization of miR-122 possibly by catalyzing 3’ monoadenylation, however, there is little evidence that this relationship is one of cause and effect. Here, we biochemically characterize Gld2 involvement in miRNA monoadenylation and its effect on miRNA stability. We find that Gld2 directly monoadenylates and stabilizes specific miRNA populations in human fibroblasts and that sensitivity to monoadenylation-induced stability depends on nucleotides in the miRNA 3‘ end. These results establish a novel mechanism of miRNA stability and resulting post-transcriptional gene regulation. Overall design: Sequencing of miRNAs to assess amount and 3'' end monoadenylation state upon Gld2 knock-down.
Publication Title
Specific miRNA stabilization by Gld2-catalyzed monoadenylation.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
RhoBTB2 is a novel Rho GTPase that undergoes loss, underexpression and mutation in breast and lung cancer. We have shown that we can mimic loss of RhoBTB2 through siRNA treatment of primary cells. We propose to perform comparative microarray analysis of primary lung cells to establish the identification of the gene targets of RhoBTb2 regulation.
Publication Title
The atypical Rho GTPase RhoBTB2 is required for expression of the chemokine CXCL14 in normal and cancerous epithelial cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Xenotransplantation holds the promise of providing an unlimited supply of donor organs for terminal patients with organ failure. The gal carbohydrate results in rejection of wild type pig grafts, however, chimerism established by expression of the GalT gene prior to transplantation in GalT knockout mice results in tolerance to Gal+ heart grafts.
Publication Title
Intragraft gene expression profile associated with the induction of tolerance.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
Description
Approximately 75% of the human genome is transcribed, the majority of which does not encode protein. However, most noncoding RNA (ncRNA) is rapidly degraded after transcription, and relatively few have established functions, questioning the significance of this observation. Here we show that esBAF, a SWI/SNF family nucleosome remodeling factor, suppresses transcription of ncRNAs from approximately 57,000 nucleosome-depleted regions (NDRs) throughout the genome of mouse embryonic stem cells (ESCs). We show that esBAF functions both to keep NDRs nucleosome-free and to promote elevated nucleosome occupancy adjacent to NDRs. Reduction of adjacent nucleosome occupancy upon esBAF depletion is strongly correlated with ncRNA expression, suggesting that flanking nucleosomes form a barrier to pervasive transcription. Upon forcing nucleosome occupancy near an NDR using a nucleosome-positioning sequence, we find that esBAF is no longer required to silence transcription. These data reveal a novel role for esBAF in suppressing pervasive transcription from open chromatin regions in ESCs. Overall design: Examine nucleosome occupancy (MNase-Seq) and transcript production (CapSeq and RNA-Seq) in EGFP KD and Smarca4 KD ESCs
Publication Title
Suppression of pervasive noncoding transcription in embryonic stem cells by esBAF.
Sample Metadata Fields
No sample metadata fields
View Samples- Caenorhabditis elegans
- 11 Downloadable Samples
- Illumina Genome Analyzer II
Description
Organisms exhibit a fascinating array of gene-silencing pathways, which have evolved in part, to confront invasive nucleic acids such as transposons and viruses. A key question raised by the existence of these pathways is how do they distinguish “self” from “non-self” nucleic acids? Evidence exists for a number of mechanisms that might facilitate detection of foreign sequences including mechanisms that sense copy-number, unpaired DNA, or aberrant RNA (e.g.dsRNA). Here we describe an RNA-induced epigenetic silencing pathway, RNAe, that permanently silences single-copy transgenes. We show that the Piwi Argonaute PRG-1 and its genomically encoded piRNA cofactors initiate RNAe, while maintenance depends on chromatin factors and the WAGO Argonaute pathway. Our findings support a model in which PRG-1 scans for foreign sequences, while two other Argonaute pathways serve as epigenetic memories of "self" and "non-self" RNAs. These findings suggest how organisms may utilize RNAi-related mechanisms not only to recognize and silence foreign genes, but also to keep inventory of all genes expressed in the germ-line. Overall design: Examine small RNA population changes in different transgene lines. FLAG::WAGO-9 was immunoprecipitated from 20 mg of lysate essentially as described (Gu et al., 2009). Small RNAs were extracted from WAGO-9 immune complexes as well as a portion of the input lysate, gel-purified, pre-treated with TAP, cloned and sequenced as described (Gu et al., 2009).
Publication Title
A Sex Chromosome piRNA Promotes Robust Dosage Compensation and Sex Determination in C. elegans.
Sample Metadata Fields
Specimen part, Disease, Subject
View Samples- Caenorhabditis elegans
- 10 Downloadable Samples
- Illumina Genome Analyzer II
Description
Diverse naturally-occurring small RNA species interact with Argonaute proteins to mediate sequence-specific regulation in animals. In addition to micro-RNAs (miRNAs), which collectively regulate thousands of target mRNAs, other endogenous small RNA species include the Piwi-associated piRNAs that are important for fertility and a less well-characterized class of small RNAs often referred to simply as endo-siRNAs. Here we have utilized deep-sequencing technology and C. elegans genetics to explore the biogenesis and function of endo-siRNAs. We describe conditional alleles of the dicer-related helicase, drh-3, that implicate DRH-3 in both the response to foreign dsRNA as well as the RNA-dependent RNA Polymerase (RdRP)-dependent biogenesis of a diverse class of endogenous small RNAs, termed 22G-RNAs. We show that 22G-RNAs are abundantly expressed in the germline and maternally inherited and are the products of at least two distinct 22G-RNA systems. One system is dependent on worm-specific AGOs, including WAGO-1, which localizes to germline nuage-related structures termed P-granules. The WAGO 22G-RNA system silences transposons, pseudogenes and cryptic loci as well as a number of genes. Finally, we demonstrate that components of the nonsense-mediated decay pathway function in at least one of the multiple, distinct WAGO surveillance pathways. These findings broaden our understanding of the biogenesis and diversity of 22G-RNA species and suggest potential novel regulatory functions for these small RNAs. Overall design: 18 samples examined. Small RNA libraries generated from: C. elegans animals with mutations in the WAGO pathway and a WAGO-1 immunopercipitate.
Publication Title
A Sex Chromosome piRNA Promotes Robust Dosage Compensation and Sex Determination in C. elegans.
Sample Metadata Fields
Disease, Cell line, Subject
View Samples