Widespread Expression of piRNA-like Molecules in Somatic Tissues
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ABSTRACT:
ORGANISM(S): Mus musculus Macaca mulatta
PROVIDER: GSE27369 | GEO | 2011/06/01
SECONDARY ACCESSION(S): PRJNA137293
REPOSITORIES: GEO
Similar Datasets
Project description:Piwi-interacting RNA (piRNA) are small RNA abundant in the germline across animal species. In fruit flies and mice, piRNA were implicated in maintenance of genomic integrity by transposable elements silencing. Outside of the germline, piRNA have only been found in Drosophila ovarian follicle cells. Previous studies further reported the presence of multiple piRNA-like small RNA (pilRNA) in fly heads and a small number of pilRNA in mouse tissues and human NK cells. Here, by analyzing high-throughput small RNA sequencing data in more than 130 fruit fly, mouse and rhesus macaque samples, we show widespread presence of pilRNA displaying all known characteristics of piRNA in multiple somatic tissues of these three species. In mouse pancreas and macaque epididymis, pilRNA abundance was compatible with piRNA abundance in the germline. Using in situ hybridizations, we further demonstrate pilRNA co-localization with mRNA expression of Piwi-family genes in all macaque tissues. These findings indicate that piRNA-like molecules might play important roles outside of the germline. Small RNA expression profiles were examined in five rhesus macaque tissues (testis, epididymis, prostate, seminal vesicles, cortex) and one mouse tissue (epididymis).
2011-06-01 | E-GEOD-27369 | biostudies-arrayexpress
Project 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. These studies show that vreteno (vret) has a role in germline development and primary piRNA regulation in Drosophila. Transposable element expression profiles from Drosophila ovaries mutant for vreteno, piwi and aubergine were compared using genome-wide mRNA expression profiling by Affymetrix GeneChip arrays (Drosophila 2.0). Key targets were validated by qPCR experiments.
2011-09-28 | E-GEOD-30360 | biostudies-arrayexpress
Project 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. These studies show that vreteno (vret) has a role in germline development and primary piRNA regulation in Drosophila.
2011-09-29 | GSE30360 | GEO
Project description:Small RNA including microRNA (miRNA) and Piwi-interacting RNA (piRNA) play important roles in germline maintenance and maturation in wide variety of species. Relatively little however is known about role played by miRNA in male germline maturation in humans and closely related primate species. Here we focused on rhesus macaques as a model species closely related to humans to study small RNA expression in testis samples throughout postnatal development and maturation. We observe clear transition in miRNA and piRNA expression resulting in the overall increase of piRNA expression levels and corresponding decrease in miRNA expression. Unexpectedly, this transition takes place at approximately one year of age – far earlier then rhesus macaque sexual maturation occurring at 4-5 years of age. Notably, contradictory to the overall trend of expression decline, a group of 29 miRNA showed marked expression increase in macaque testis at approximately five years of age – the time interval associated with sexual maturation. Keywords: miRNA piRNA Age Series Rhesus macaque post-mortem testicle samples were collected. The age ranges of the indibiual in rhesus macaque covered the whole life span fom newborn to death.
2013-03-05 | E-GEOD-44820 | biostudies-arrayexpress
Project description:Transposable elements are a serious threat for genome integrity and their control via small RNA mediated silencing pathways is an ancient strategy. The fruit fly Drosophila melanogaster has two silencing mechanisms that repress TEs expression: endogenous siRNAs (esiRNAs or endo-siRNAs) and Piwi-interacting small RNAs (piRNAs). The biogenesis of endo-siRNAs involves Loqs-PD, which acts predominantly during processing of dsRNA by Dcr-2, and R2D2 that primarily helps to direct siRNAs for loading into Ago2. We provide deep sequencing evidence consistent with the idea that R2D2 and Loqs-PD can function in part redundantly. Certain transposons display a preference for either dsRBD-protein for production or loading; this appeared to correlate neither with overall abundance, classification of the transposon or a specific site of genomic origin. The endo-siRNA biogenesis pathway in the germline operates according to the same principles as the existing model for the soma, and its impairment does not significantly affect piRNAs. Expanding the analysis, we confirmed the occurrence of somatic piRNA-like RNAs (pilRNAs) that show a ping-pong signature. We detected expression of the Piwi-family protein mRNAs only barely above background, indicating that the somatic pilRNAs may arise from a small sub-population of somatic cells that express a functional piRNA pathway.
2015-01-19 | GSE45290 | GEO
Project description:PIWI-interacting RNAs (piRNAs) are animal gonad-specific small RNAs that control the activity of transposable elements. Long single stranded RNAs from a variety of sources are substrates for the nebulous primary processing pathway that converts these into thousands of 24-30 nucleotide (nt) piRNAs. How these transcripts are selected as precursors is not known. Here we show that targeting a transcript with PIWI slicer activity of cysosolic Ago3 is sufficient to trigger ~30-nt waves of non-overlapping primary piRNAs in the fly ovarian germline. The generated primary piRNAs are almost exclusively loaded into the nuclear PIWI protein, Piwi. In the fly ovarian somatic environment we find that an RNA fragment from the 5? end of a piRNA cluster is able to direct a heterologous sequence into primary processing. This piRNA trigger sequence (PTS) element drives generation of overlapping piRNAs from the transcript. Both mechanisms proceed with general 5?-3? directionality. We propose that the former pathway serves to link cytoplasmic silencing of a target to nuclear transcriptional repression, while the latter extracts silencing information from a wide variety of genomic sources including piRNA clusters, select protein coding and transposon transcripts. Total or immunoprecipitated small RNAs were purified from transfected BmN4 cells, Drosophila ovarian somatic cells (OSC) and from fly ovaries and high-throughput sequencing libraries were prepared. The mouse testicular RNAs were purified after ribozero treatment.
2015-07-09 | E-GEOD-69102 | biostudies-arrayexpress
Project description:Small RNA including microRNA (miRNA) and Piwi-interacting RNA (piRNA) play important roles in germline maintenance and maturation in wide variety of species. Relatively little however is known about role played by miRNA in male germline maturation in humans and closely related primate species. Here we focused on rhesus macaques as a model species closely related to humans to study small RNA expression in testis samples throughout postnatal development and maturation. We observe clear transition in miRNA and piRNA expression resulting in the overall increase of piRNA expression levels and corresponding decrease in miRNA expression. Unexpectedly, this transition takes place at approximately one year of age – far earlier then rhesus macaque sexual maturation occurring at 4-5 years of age. Notably, contradictory to the overall trend of expression decline, a group of 29 miRNA showed marked expression increase in macaque testis at approximately five years of age – the time interval associated with sexual maturation. Keywords: miRNA piRNA Age Series
2013-03-05 | GSE44820 | GEO
Project description:23-29 nt Piwi-interacting RNAs (piRNAs) are crucial components of the ribonucleoprotein complexes which silence the most abundant class of mobile genetic elements in human genome, retrotransposons, in germline (germ) cells. In these cells, antisense piRNAs serve as RNA guides for Piwi proteins, base pairing with transposon RNAs which are subsequently cleaved by Piwi proteins. Germ cells belong to special class of stem cells which ultimately give rise to eggs and sperm and therefore, to next generations. Therefore, piRNAs protect next-generation genomes from devastating mutations caused by transposon insertions. Although, role of piRNAs in germ cells has been studied, functions of piRNAs and their associated proteins in somatic cells are not well understood. Importantly, Piwi proteins are expressed in the fruit fly Drosophila brain and are required for the silencing of transposable elements there, clearly indicating that Piwi-associated piRNAs are involved in this process in the brain. Furthermore, piRNAs have been implicated in the memory formation mechanisms in Aplysia brain. In addition to Piwi proteins, their associated partner, molecular scaffold Tudor protein, participates in piRNA biogenesis in germ cells and it is absolutely required for germline development. However, although tudor gene is expressed in the fly brain, its role in the central nervous system is not understood. In this study, we look at the role of Tudor as an essential player in piRNA biogenesis in Drosophila brain.
2020-11-27 | GSE149748 | GEO
Project description:PIWI-interacting RNAs (piRNAs) are genomically-encoded small RNAs that regulate germ cell development and guarantee germline integrity. Mature piRNAs engage Piwi Argonaute proteins to silence complementary transcripts, including transposable elements and endogenous genes. To date, piRNA biogenesis mechanisms are still unclear. Here, we show that the RNA Polymerase II subunit RPB-9 is required to promote transcription elongation at piRNA loci. Through genetic and biochemical experiments, we demonstrate that rpb-9-mediated piRNA production is needed to repress two DNA transposon families and a subset of somatic genes in the C. elegans germline.
2020-12-07 | PXD018657 | Pride
Project description:Transposable elements are a serious threat for genome integrity and their control via small RNA mediated silencing pathways is an ancient strategy. The fruit fly Drosophila melanogaster has two silencing mechanisms that repress TEs expression: endogenous siRNAs (esiRNAs or endo-siRNAs) and Piwi-interacting small RNAs (piRNAs). The biogenesis of endo-siRNAs involves Loqs-PD, which acts predominantly during processing of dsRNA by Dcr-2, and R2D2 that primarily helps to direct siRNAs for loading into Ago2. We provide deep sequencing evidence consistent with the idea that R2D2 and Loqs-PD can function in part redundantly. Certain transposons display a preference for either dsRBD-protein for production or loading; this appeared to correlate neither with overall abundance, classification of the transposon or a specific site of genomic origin. The endo-siRNA biogenesis pathway in the germline operates according to the same principles as the existing model for the soma, and its impairment does not significantly affect piRNAs. Expanding the analysis, we confirmed the occurrence of somatic piRNA-like RNAs (pilRNAs) that show a ping-pong signature. We detected expression of the Piwi-family protein mRNAs only barely above background, indicating that the somatic pilRNAs may arise from a small sub-population of somatic cells that express a functional piRNA pathway. small RNA sampling experiment; small RNAs were prepared from head & thorax as well as dissected ovaries of Adult female Drosophila melanogaster. We used homozygous mutants of the dsRBD proteins Loqs and r2d2 to determine their contribution to the biogenesis of transposon-derived small RNAs. Heterozygous mutant animals served as control. For each RNA sample, we performed one deep-sequencing run without any treatment, and in parallel one sequencing run after periodate oxidation and beta-elimination. After this treatment, only Ago2, Piwi, Aub and Ago3-loaded small RNAs remain as they carry a 2'-O-methyl modification at their 3'-end. This helps to determine the loading status of the small RNAs detected. In total 8 different RNA samples were prepared and 16 libraries were sequenced.
2015-01-19 | E-GEOD-45290 | biostudies-arrayexpress