Small non-coding RNAs that associate with Piwi proteins, called piRNAs, serve as guides for repression of diverse transposable elements in germ cells of Metazoa. In Drosophila, the genomic regions that give rise to piRNAs, the so-called piRNA clusters, are transcribed to generate long precursor molecules that are processed into mature piRNAs. How genomic regions that give rise to piRNA precursor transcripts are differentiated from the rest of the genome and how these transcripts are specifically channeled into the piRNA biogenesis pathway are not known. We found that trans-generationally inherited piRNAs provide the critical trigger for piRNA production from homologous genomic regions in the next generation by two different mechanisms. First, inherited piRNAs enhance processing of homologous transcripts into mature piRNAs by initiating the ping-pong cycle in the cytoplasm. Second, inherited piRNAs induce installment of the H3K9me3 mark on genomic piRNA cluster sequences. The HP1 homolog Rhino binds to the H3K9me3 mark through its chromodomain and is enriched over piRNA clusters. Rhino recruits the piRNA biogenesis factor Cutoff to piRNA clusters and is required for efficient transcription of piRNA precursors. We propose that trans-generationally inherited piRNAs act as an epigenetic memory for identification of substrates for piRNA biogenesis on two levels, by inducing a permissive chromatin environment for piRNA precursor synthesis and by enhancing processing of these precursors. Overall design: total RNA sequencing of RNA from ovaries of cuff+/- or cuff-/- flies
Transgenerationally inherited piRNAs trigger piRNA biogenesis by changing the chromatin of piRNA clusters and inducing precursor processing.
Specimen part, Subject
View SamplesSmall non-coding RNAs that associate with Piwi proteins, called piRNAs, serve as guides for repression of diverse transposable elements in germ cells of Metazoa. In Drosophila, the genomic regions that give rise to piRNAs, the so-called piRNA clusters, are transcribed to generate long precursor molecules that are processed into mature piRNAs. How genomic regions that give rise to piRNA precursor transcripts are differentiated from the rest of the genome and how these transcripts are specifically channeled into the piRNA biogenesis pathway are not known. We found that trans-generationally inherited piRNAs provide the critical trigger for piRNA production from homologous genomic regions in the next generation by two different mechanisms. First, inherited piRNAs enhance processing of homologous transcripts into mature piRNAs by initiating the ping-pong cycle in the cytoplasm. Second, inherited piRNAs induce installment of the H3K9me3 mark on genomic piRNA cluster sequences. The HP1 homolog Rhino binds to the H3K9me3 mark through its chromodomain and is enriched over piRNA clusters. Rhino recruits the piRNA biogenesis factor Cutoff to piRNA clusters and is required for efficient transcription of piRNA precursors. We propose that trans-generationally inherited piRNAs act as an epigenetic memory for identification of substrates for piRNA biogenesis on two levels, by inducing a permissive chromatin environment for piRNA precursor synthesis and by enhancing processing of these precursors. Overall design: nuclear run-on in wildtype and Rhino knockdown to investigate the transcriptional activity in Rhino knockdown compared to wildtype
Transgenerationally inherited piRNAs trigger piRNA biogenesis by changing the chromatin of piRNA clusters and inducing precursor processing.
Specimen part, Subject
View SamplesSmall non-coding RNAs that associate with Piwi proteins, called piRNAs, serve as guides for repression of diverse transposable elements in germ cells of Metazoa. In Drosophila, the genomic regions that give rise to piRNAs, the so-called piRNA clusters, are transcribed to generate long precursor molecules that are processed into mature piRNAs. How genomic regions that give rise to piRNA precursor transcripts are differentiated from the rest of the genome and how these transcripts are specifically channeled into the piRNA biogenesis pathway are not known. We found that trans-generationally inherited piRNAs provide the critical trigger for piRNA production from homologous genomic regions in the next generation by two different mechanisms. First, inherited piRNAs enhance processing of homologous transcripts into mature piRNAs by initiating the ping-pong cycle in the cytoplasm. Second, inherited piRNAs induce installment of the H3K9me3 mark on genomic piRNA cluster sequences. The HP1 homolog Rhino binds to the H3K9me3 mark through its chromodomain and is enriched over piRNA clusters. Rhino recruits the piRNA biogenesis factor Cutoff to piRNA clusters and is required for efficient transcription of piRNA precursors. We propose that trans-generationally inherited piRNAs act as an epigenetic memory for identification of substrates for piRNA biogenesis on two levels, by inducing a permissive chromatin environment for piRNA precursor synthesis and by enhancing processing of these precursors. Overall design: total RNA sequencing of RNA from ovaries of shWhite and Rhino knockdown flies
Transgenerationally inherited piRNAs trigger piRNA biogenesis by changing the chromatin of piRNA clusters and inducing precursor processing.
Specimen part, Subject
View SamplesChlamydia trachomatis serovariants are responsible for either Trachoma, the leading cause of infectious blindness or sexually transmitted disease, wherein the endocervix is the most frequently infected site in women. Disease caused by Chlamydia typically involves chronic inflammation and scarring. Recent work with a live-attenuated A2497 plasmid deficient vaccine strain (A2497-) demonstrated protection in nonhuman primates against trachoma and a lack of measurable ocular pathology in A2497- infected monkeys. We therefore performed host cell transcriptome analysis of Hela cells infected with A2497 plasmid-containing (A2497) and A2497- Chlamydia over time. Our results indicate that relative to wild type A2497, the A2497- variant illicits a transcriptome response indicative of lowered inflammation response a delayed apoptosis response, a reduction in immune cell recruitement cytokine expression and a reduction in genes involved in cell proliferation and or fibrosis-like activities. The data provided here suggests a model that may explain how plasmid deficient chlamydia may provide an immuno-protective response without the pathology normally seen with plasmid-containing bacteria.
Transcriptional profiling of human epithelial cells infected with plasmid-bearing and plasmid-deficient Chlamydia trachomatis.
Disease, Cell line
View SamplesEpiblast stem cells (EpiSCs) were derived from the epiblast or the ectoderm (epi/ect) of pre-gastrula stage to late-bud stage mouse embryos. To identify if the EpiSCs retain any original stage specific characteristics or which developmental stage of epi/ect they most closely related to, we performed microarray analysis to compare the gene expression profile of multiple EpiSC lines with that of epi/ect of 7 different stages.
The transcriptional and functional properties of mouse epiblast stem cells resemble the anterior primitive streak.
Specimen part
View SamplesBackground: Blocking the action of the pro-inflammatory cytokine interleukin-1 (IL-1) reduces beta-cell secretory dysfunction and apoptosis in vitro, diabetes incidence in animal models of Type 1 diabetes mellitus (T1D), and glycaemia via improved beta-cell function in patients with T2D. We hypothesised that anakinra, a recombinant human IL-1 receptor antagonist, improves beta-cell function in patients with new-onset T1D. Methods: In an individually randomised, two-group parallel trial involving 14 European tertiary referral centers, 69 patients aged 18-35 with T1D, < 12 weeks of symptoms, and standard mixed meal test (MMT) stimulated C-peptide 200 pM were enrolled between January, 2009 and July, 2011 and assigned by centralised computer-generated blocked randomisation with locked computer-file concealment to treatment with 100 mg anakinra (n=35) subcutaneously once daily or placebo (n=34) for 9 months as add-on to conventional therapy. Participants and care-givers, but not data monitoring unit, were masked to group assignment. The primary end-point was change in the two-hour area-under-the-curve C-peptide response to MMT, and secondary end-points changes in insulin requirements, glycaemia, and inflammatory markers at one, three, six, and nine months. Findings: The study was prematurely terminated due to slow accrual and is closed to follow-up. No interim analysis was performed. Ten patients withdrew in the anakinra and eight in the placebo arm, leaving 25 and 26 patients to be analysed, respectively. There was no statistical difference in adverse event category reporting between arms. Interpretation: Anakinra-treatment in T1D was safe, but the trial failed to meet primary and secondary outcome measures.
Interleukin-1 antagonism moderates the inflammatory state associated with Type 1 diabetes during clinical trials conducted at disease onset.
Subject, Time
View SamplesBackground: Blocking the action of the pro-inflammatory cytokine interleukin-1 (IL-1) reduces beta-cell secretory dysfunction and apoptosis in vitro, diabetes incidence in animal models of Type 1 diabetes mellitus (T1D), and glycaemia via improved beta-cell function in patients with T2D. We hypothesised that canakinumab, a monoclonal antibody to IL-1B, improves beta-cell function in patients with new-onset T1D. Methods: In an individually randomised, two-group parallel trial involving 12 sites in US, 69 patients aged 6-45 with T1D, < 12 weeks of symptoms, and assigned by centralised computer-generated blocked randomisation with locked computer-file concealment to treatment with 2 mg/kg (maximum 300 mg) canakinumab (n=45) or placebo (n=22) monthly for 12 months as add-on to conventional therapy. Participants and care-givers, but not data monitoring unit, were masked to group assignment. The primary end-point was change in the two-hour area-under-the-curve C-peptide response to MMT 12 months.
Interleukin-1 antagonism moderates the inflammatory state associated with Type 1 diabetes during clinical trials conducted at disease onset.
Subject, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cis-transcriptional variation in maize inbred lines B73 and Mo17 leads to additive expression patterns in the F1 hybrid.
No sample metadata fields
View SamplesSoybean aphids are phloem-feeding pests that can cause significant yield losses in soybean plants. Soybean aphids thrive on susceptible soybean lines but not on resistant lines.
Multiple phytohormone signals control the transcriptional response to soybean aphid infestation in susceptible and resistant soybean plants.
Specimen part
View SamplesMicroarray analysis of gene expression patterns in immature ear, seedling, and embryo tissues from the maize inbred lines B73 and Mo17 identified numerous genes with variable expression. Some genes had detectable expression in only one of the two inbreds; most of these genes were detected in the genomic DNA of both inbreds, indicating that the expression differences are likely caused by differential regulation rather than by differences in gene content. Gene expression was also monitored in the reciprocal F1 hybrids B73xMo17 and Mo17xB73. The reciprocal F1 hybrid lines did not display parental effects on gene expression levels. Approximately 80% of the differentially expressed genes displayed additive expression patterns in the hybrids relative to the inbred parents. The approximately 20% of genes that display nonadditive expression patterns tend to be expressed at levels within the parental range, with minimal evidence for novel expression levels greater than the high parent or less than the low parent. Analysis of allele-specific expression patterns in the hybrid suggested that intraspecific variation in gene expression levels is largely attributable to cis-regulatory variation in maize. Collectively, our data suggest that allelic cis-regulatory variation between B73 and Mo17 dictates maintenance of inbred allelic expression levels in the F1 hybrid, resulting in additive expression patterns.
Cis-transcriptional variation in maize inbred lines B73 and Mo17 leads to additive expression patterns in the F1 hybrid.
No sample metadata fields
View Samples