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SRP058190
Mus musculus
13 Downloadable Samples
IlluminaHiSeq2500
Description
The goal of this study is to compare the transcriptome of the 2 MVT1 subpopulations in order to identify new genes and pathways that stands beyond the CD24+ aggressive phenotype Overall design: mRNA profiles of CD24- and CD24+ cells were generated by deep sequencing, in triplicate, using Illumina HiSeq 2500
Publication Title
Deep sequencing of mRNA in CD24(-) and CD24(+) mammary carcinoma Mvt1 cell line.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 13 Downloadable Samples
- Illumina HiSeq 2000
Description
In animal gonads, 23-30nt long PIWI interacting RNAs (piRNAs) guarantee genome integrity by guiding the sequence specific silencing of selfish genetic elements such as transposons. Two major branches of piRNA biogenesis, namely primary processing and ping-pong amplification, feed into the PIWI clade of Argonaute proteins. Despite our conceptual understanding of piRNA biogenesis, major gaps exist in the mechanistic understanding of the underlying molecular processes as well as in the knowledge of the involved players. Here, we demonstrate an essential role for the female sterility gene shutdown in the piRNA pathway. Shutdown, an evolutionarily conserved co-chaperone of the immunophilin class is the first piRNA biogenesis factor that is essential for all primary and secondary piRNA populations in Drosophila. Based on these findings, we define distinct groups of piRNA biogenesis factors and reveal the core concept of how PIWI family proteins are hard-wired into piRNA biogenesis processes. Overall design: small-RNA libraries from 2 control samples and 7 knock-down samples of D. mel. ovaries and 2 small-RNA profiles from Piwi IP and Aub IP from OSCs.
Publication Title
The cochaperone shutdown defines a group of biogenesis factors essential for all piRNA populations in Drosophila.
Sample Metadata Fields
Specimen part, Subject
View Samples- Drosophila melanogaster
- 5 Downloadable Samples
- Illumina Genome Analyzer II
Description
In Drosophila, PIWI proteins and bound PIWI interacting RNAs (piRNAs) form the core of a small RNA mediated defense system against selfish genetic elements. Within germline cells piRNAs are processed from piRNA clusters and transposons to be loaded into Piwi/Aubergine/AGO3 and a subset of piRNAs undergoes target dependent amplification. In contrast, gonadal somatic support cells express only Piwi, lack signs of piRNA amplification and exhibit primary piRNA biogenesis from piRNA clusters. Neither piRNA processing/loading nor Piwi mediated target silencing is understood at the genetic, cellular or molecular level. We developed an in vivo RNAi assay for the somatic piRNA pathway and identified the RNA helicase Armitage, the Tudor domain containing RNA helicase Yb and the putative nuclease Zucchini as essential factors for primary piRNA biogenesis. Lack of any of these proteins leads to transposon de-silencing, to a collapse in piRNA levels and to a failure in Piwi nuclear accumulation. We show that Armitage and Yb interact physically and co-localize in cytoplasmic Yb-bodies, which flank P-bodies. Loss of Zucchini leads to an accumulation of Piwi and Armitage in Yb-bodies indicating that Yb-bodies are sites of primary piRNA biogenesis. Overall design: small RNA libraries were prepared from Piwi immuno-precipitates of five different genotypes
Publication Title
An in vivo RNAi assay identifies major genetic and cellular requirements for primary piRNA biogenesis in Drosophila.
Sample Metadata Fields
Subject
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Illumina Genome Analyzer II
Description
Drosophila melanogaster expresses three classes of small RNAs, which are classified according to their mechanisms of biogenesis. MicroRNAs are ~22-23-nt, ubiquitously expressed small RNAs that are sequentially processed from hairpin-like precursors by Drosha/Pasha and Dcr-1/Loquacious complexes. MicroRNAs usually associate with AGO1 and regulate the expression of protein-coding genes. Piwi-interacting RNAs (piRNAs) of ~24-28-nt associate with Piwi-family proteins and can arise from single-stranded precursors. piRNAs function in transposon silencing and are mainly restricted to gonadal tissues. Endo-siRNAs are found in both germline and somatic tissues. These ~21-nt RNAs are produced by a distinct Dicer, Dcr-2, and do not depend on Drosha/Pasha complexes. They predominantly bind to AGO2 and target both mobile elements and protein-coding genes. Surprisingly, a subset of endo-siRNAs strongly depend for their production on the dsRNA-binding protein Loquacious (Loqs), thought generally to be a partner for Dcr-1 and a co-factor for miRNA biogenesis. Endo-siRNA production depends on a specific Loqs isoform, Loqs-PD, which is distinct from the one, Loqs-PB, required for the production of microRNAs. Paralleling their roles in the biogenesis of distinct small RNA classes, Loqs-PD and Loqs-PB bind to different Dicer proteins, with Dcr-1/Loqs-PB complexes and Dcr-2/Loqs-PD complexes driving microRNA and endo-siRNA biogenesis, respectively. Small RNA profiling by high throughput sequencing Overall design: Total RNA was isolated using Trizol reagent (Invitrogen) and size-fractionated by PAGE into 19-24nt. These were independently processed and sequenced using the Illumina GAII platform. In total, six libraries were analyzed.
Publication Title
Processing of Drosophila endo-siRNAs depends on a specific Loquacious isoform.
Sample Metadata Fields
Cell line, Subject
View Samples- Drosophila melanogaster
- 12 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
In Drosophila, Piwi proteins associate with Piwi-interacting RNAs (piRNAs) and protect the germline genome by silencing mobile genetic elements. This defense system acts in germline and gonadal somatic tissue to preserve germline development. Genetic control for these silencing pathways varies greatly between tissues of the gonad. Here, we identified Vreteno (Vret), a novel gonad-specific protein essential for germline development. Vret is required for piRNA-based transposon regulation in both germline and somatic gonadal tissues. We show that Vret, which contains Tudor domains, associates physically with Piwi and Aubergine (Aub), stabilizing these proteins via a gonad-specific mechanism, absent in other fly tissues. In the absence of vret, Piwi-bound piRNAs are lost without changes in piRNA precursor transcript production, supporting a role for Vret in primary piRNA biogenesis. In the germline, piRNAs can engage in an Aub/Argonaute 3 (AGO3)-dependent amplification in the absence of Vret, suggesting that Vret function can distinguish between primary piRNAs loaded into Piwi/Aub complexes and piRNAs engaged in the amplification cycle. We propose that Vret acts at an early step in primary piRNA processing where it plays an essential role in transposon regulation.
Publication Title
Vreteno, a gonad-specific protein, is essential for germline development and primary piRNA biogenesis in Drosophila.
Sample Metadata Fields
Specimen part, Disease
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Illumina HiSeq 2000
Description
The exon junction complex (EJC) is a highly conserved ribonucleoprotein complex which binds RNAs at a late stage of the splicing reaction and remains associated following export to the cytoplasm. This complex is involved in several cellular post-transcriptional processes including mRNA localization, translation and degradation. The EJC plays an additional role in the splicing of a subset of genes in Drosophila and in human cells but the underlying mechanism remains to be elucidated. Here, we have found a novel function for the EJC and its splicing subunit RnpS1 in preventing transposon accumulation in both Drosophila germline and surrounding follicular cells. This function is mediated specifically through the control of the splicing of the piwi transcript. In absence of RnpS1 one of the piwi intron is retained. This intron contains a weak 5’ splice site as well as degenerate transposon fragments, reminiscent of heterochromatic introns. In addition, we identified a small A/T rich region, which alters its polypyrimidine tract (PPT) and confers the RnpS1’s dependency. Finally, we showed that the removal of this intron by RnpS1 requires the initial splicing of the flanking introns, suggesting a model in which the EJC facilitates the splicing of challenging introns following its initial deposition to adjacent exon junctions. Overall design: In total there are 4 different conditions. Comparisons were made between piwi mutant vs control piwi and rnps1 KD vs controls RnpS1
Publication Title
The exon junction complex controls transposable element activity by ensuring faithful splicing of the piwi transcript.
Sample Metadata Fields
Specimen part, Subject
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
- Illumina Genome Analyzer II
Description
Here, we analyzed two small RNA libraries derived from ovarian tissue mutant for either the Drosophila SETDB1 gene, or the Bam gene. Here we show that deposition of histone 3 lysine 9 by the methyltransferase dSETDB1 (egg) is required for piRNA cluster transcription. In the absence of dSETDB1, cluster precursor transcription collapses in germline and somatic gonadal cells and TEs are activated, resulting in germline loss and a block in germline stem cell differentiation. We propose that heterochromatin protects the germline by activating the piRNA pathway. Keyword : Epigenetics Overall design: 2 libraries were analyzed, with 1 being a developmental control (Bam Mutant).
Publication Title
piRNA production requires heterochromatin formation in Drosophila.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
- Illumina Genome Analyzer II
Description
Here, we analyzed small RNA libraries derived from ovarian tissues heterozygous or mutant for the Tudor gene, Vreteno. In the absence of vret, Piwi-bound piRNAs are lost without changes in piRNA precursor transcript production, supporting a role for Vret in primary piRNA biogenesis. In the germline, piRNAs can engage in an Aub/Argonaute 3 (AGO3)-dependent amplification in the absence of Vret, suggesting that Vret function can distinguish between primary piRNAs loaded into Piwi/Aub complexes and piRNAs engaged in the amplification cycle. We propose that Vret acts at an early step in primary piRNA processing where it plays an essential role in transposon regulation. Keyword : Epigenetics Overall design: 2 libraries were analyzed, with 1 being a control (heterozygote).
Publication Title
Vreteno, a gonad-specific protein, is essential for germline development and primary piRNA biogenesis in Drosophila.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 12 Downloadable Samples
- Illumina Genome Analyzer II, Illumina Genome Analyzer IIx
Description
Here we show that MIWI is a small RNA-guided ribonuclease (Slicer) that requires extensive complementarity for target cleavage in vitro. Disruption of its catalytic activity in mice by a single point mutation results in male infertility and displays increased accumulation of LINE1 transposon transcripts. Overall design: MIWI-associated piRNAs from different genotypes were sequenced. Total RNA from purified round spermatids were subjected to Ribozero purification and strand-specific RNAseq lib prepared. Global 5'' RACE library was prepare from indicated genotypes.
Publication Title
Miwi catalysis is required for piRNA amplification-independent LINE1 transposon silencing.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Here we show that MIWI is a small RNA-guided ribonuclease (Slicer) that requires extensive complementarity for target cleavage in vitro. Disruption of its catalytic activity in mice by a single point mutation results in male infertility and displays increased accumulation of LINE1 transposon transcripts.
Publication Title
Miwi catalysis is required for piRNA amplification-independent LINE1 transposon silencing.
Sample Metadata Fields
No sample metadata fields
View Samples