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SRP013751
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
- 6 Downloadable Samples
- Illumina Genome Analyzer IIx, Illumina HiSeq 2000
Description
The animal piRNA pathway is a small RNA silencing system that acts in gonads and protects the genome against the deleterious influence of transposons. A major bottleneck in the field is the lack of comprehensive knowledge of the factors and molecular processes that constitute this pathway. We conducted an RNAi screen in Drosophila and identified ~50 genes that strongly impact the ovarian somatic piRNA pathway. Many identified genes fall into functional categories that indicate essential roles for mitochondrial metabolism, RNA export, the nuclear pore, transcription elongation and chromatin regulation in the pathway. Follow-up studies on two factors demonstrate the identification of components acting at distinct hierarchical levels of the pathway. Finally, we define CG2183/Gasz as a novel primary piRNA biogenesis factor in somatic and germline cells. Based on the similarities between insect and vertebrate piRNA pathways our results have far-reaching implications for the understanding of this conserved genome defense system. Overall design: Steady-state RNA levels in wild-type ovarian somatic cells (OSC) and RNAi knock-downs of the piRNA pathway components.
Publication Title
The genetic makeup of the Drosophila piRNA pathway.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 125 Downloadable Samples
Illumina HumanWG-6 v3.0 expression beadchip
Description
Genome-wide analysis of decidual transcriptome in pre-eclampsia compared with normotensive controls to find differentially expressed genes/pathways.
Publication Title
Genome-wide transcriptome directed pathway analysis of maternal pre-eclampsia susceptibility genes.
Sample Metadata Fields
Specimen part, Disease stage
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Illumina Genome Analyzer II
Description
PIWI proteins and their bound piRNAs form the core of a gonad specific small RNA silencing pathway in animals that protects the genome against the deleterious activity of transposable elements. Recent studies linked the piRNA pathway to TUDOR biology, where TUDOR domains of various proteins recognize and bind symmetrically methylated Arginine residues in PIWI proteins. We systematically analyzed the Drosophila TUDOR protein family and identified three previously not characterized TUDOR domain-containing genes (CG4771, CG14303 and CG11133) as essential piRNA pathway members. We characterized CG4771 (Avocado) in detail and demonstrate a critical role for this protein during primary piRNA biogenesis in somatic and germline cells of the ovary. Avocado physically and/or genetically interacts with the primary pathway components Piwi, Armitage, Yb and Zucchini. Avocado also interacts with the Tdrd12 orthologs CG11133 and CG31755, which are essential for primary piRNA biogenesis in the germline and probably functionally replace the related and soma specific factor Yb. Overall design: small RNA libraries were prepared from total RNA isolation of 8 different genotypes
Publication Title
A systematic analysis of Drosophila TUDOR domain-containing proteins identifies Vreteno and the Tdrd12 family as essential primary piRNA pathway factors.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 6 Downloadable Samples
- Illumina HiSeq 4000
Description
Sequencing of olaparib-resistant PEO1 derivatives (C4, C5, C10 and C18) and parental PEO1 (P1 and P2) cells was performed in order to determine mechanisms of acquired resistance in the resistant cell lines. PEO1 parental cell lines were authenticated prior to sequencing. PEO1 parental were confirmed to be BRCA2-mutated (5139C>G). Olaparib PEO1 resistant cells were generated through a step-wise escalation of olaparib (10nM to 8uM olaparib). In olaparib resistant lines an increase canonical Wnt signaling and loss of of non-canonical Wnt signaling was observed. Overall design: Sequencing of olaparib-resistant PEO1 derivatives (C4, C5, C10, and C18) and parental PEO1 cells was performed in order to determine mecahnisms of acquired resistance.
Publication Title
Activation of Wnt signaling promotes olaparib resistant ovarian cancer.
Sample Metadata Fields
Cell line, Subject
View Samples- Mus musculus
- 2 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Adipose tissue iNKT cells have different functions than iNKT cells in the blood and other organs.
Publication Title
Regulatory iNKT cells lack expression of the transcription factor PLZF and control the homeostasis of T(reg) cells and macrophages in adipose tissue.
Sample Metadata Fields
Age, Specimen part
View Samples- Macaca mulatta
- 8 Downloadable Samples
- Affymetrix Rhesus Macaque Genome Array (rhesus)
Description
It is often overlooked that human ESCs are generated from in vitro cultured, often surplus/discard, embryos considered unsuitable for transfer in infertility clinics. In vitro culture of preimplantation embryos has been associated with a number of perturbations, including ultrastructure, gene expression, metabolism and post-transfer development. We report here the transcriptional profiles characteristic of ESC lines generated from either in vitro cultured or in vivo derived embryos.
Publication Title
Transcriptional differences between rhesus embryonic stem cells generated from in vitro and in vivo derived embryos.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Lacciac Acid A was indentified as an inhibitor of DMNT1. MCF-7 cells were treated with Lacciac Acid A (200 uM) for 5 days. Changes in gene expression were identified by using Affymetrix Human gene ST1.0 arrays. We used microarrays to determine global changes in gene expression upon treatment with Lacciac Acid A an inhibitor of DMNT1.
Publication Title
Laccaic acid A is a direct, DNA-competitive inhibitor of DNA methyltransferase 1.
Sample Metadata Fields
Specimen part
View Samples