Heat shock factor 5 is indispensable for pachynema progression and LINE1 silencing during spermatogenesis in mice [smallRNA-Seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE327624 | GEO | 2026/04/17
REPOSITORIES: GEO
Similar Datasets
Project description:Germline-specific RNA helicase Spindle-E (Spn-E) is known to be essential for piRNA silencing in Drosophila that takes place mainly in the perinuclear nuage granules. Loss-of-function spn-E mutations lead to tandem Stellate genes derepression in the testes and retrotransposon mobilization in the ovaries. However, Spn-E functions in the piRNA pathway are still obscure. Analysis of total library of short RNAs from the testes of spn-E heterozygous flies revealed the presence of abundant piRNA ping-pong pairs originating from Su(Ste) transcripts. The abundance of these ping-pong pairs were sharply reduced in the library from the testes of spn-E mutants. Thus we found that ping-pong mechanism contributed to Su(Ste) piRNA generation in the testes. The lack of Spn-E caused a significant drop of protein levels of key ping-pong participants, Aubergine (Aub) and AGO3 proteins of PIWI subfamily, in the germline of both males and females, but did not disrupt of their assembly in nuage granules. We found that observed decline of the protein expression was not caused by suppression of aub and ago3 transcription as well as total transcription, indicating possible contribution of Spn-E to post-transcriptional regulation.
2016-06-08 | GSE50984 | GEO
Project description:The piRNA pathway is studied in great detail in Drosophila female germline. In this study we show that unlike the female germline where all Piwi proteins are expressed throughout oogenesis, Ago3 - a Piwi family protein shows a spatial expression male germline. To understand dynamics of piRNA pathway during spermatogonia and primary spermatocyte stages of male germline development, we used arrest mutants. The bag of marbles (bam) and benign gonial cell neoplasm (bgcn) mutants have only early mitotic dividing germline cells in the testes due to failure to progress to primary spermatocyte stage, the cannonball (can) and spermatocyte arrest (sa) mutant germline cells cannot progress beyond primary spermatocyte stage. To investigate the dynamics of the piRNA pathway during spermatogenesis in spermatogonia and primary spermatocyte stages, we used testicular tissues from these stage-specific arrested mutants. While we used entire bam and bgcn mutant testes for spermatogonia purification, we while we manually removed the apical regions of can and sa mutant testes to exclude mitotically dividing undifferentiated germline cells for primary spermatocytes purification. Our results show that piRNAs mapping to transposons are more abundant in spermatogonia, whereas those mapping to Suppressor of Stellate [Su(Ste)] and AT-chX are mostly expressed in primary spermatocytes. Furthermore we observed that transposon-mapping piRNAs with ping-pong signature are more abundant in spermatogonia albeit still detectable in primary spermatocytes where Ago3 is not expressed. These results suggest that robust piRNA production via ping-pong cycle takes place in spermatogonia, and to a lesser extent in primary spermatocytes even in the absence of Ago3. Consistently, piRNAs from ago3 mutant testes also exhibit the ping-pong signature, confirming that a non-canonical ping-pong cycle is acting during spermatogenesis. Our study provides a developmental dimension to the piRNA pathway and uncovers a new mechanism used in the male germline to silence transposons.
2016-08-10 | GSE69417 | GEO
Project description:The piRNA pathway is studied in great detail in Drosophila female germline. In this study we show that unlike the female germline where all Piwi proteins are expressed throughout oogenesis, Ago3 - a Piwi family protein shows a spatial expression male germline. To understand dynamics of piRNA pathway during spermatogonia and primary spermatocyte stages of male germline development, we used arrest mutants. The bag of marbles (bam) and benign gonial cell neoplasm (bgcn) mutants have only early mitotic dividing germline cells in the testes due to failure to progress to primary spermatocyte stage, the cannonball (can) and spermatocyte arrest (sa) mutant germline cells cannot progress beyond primary spermatocyte stage. To investigate the dynamics of the piRNA pathway during spermatogenesis in spermatogonia and primary spermatocyte stages, we used testicular tissues from these stage-specific arrested mutants. While we used entire bam and bgcn mutant testes for spermatogonia purification, we while we manually removed the apical regions of can and sa mutant testes to exclude mitotically dividing undifferentiated germline cells for primary spermatocytes purification. Our results show that piRNAs mapping to transposons are more abundant in spermatogonia, whereas those mapping to Suppressor of Stellate [Su(Ste)] and AT-chX are mostly expressed in primary spermatocytes. Furthermore we observed that transposon-mapping piRNAs with ping-pong signature are more abundant in spermatogonia albeit still detectable in primary spermatocytes where Ago3 is not expressed. These results suggest that robust piRNA production via ping-pong cycle takes place in spermatogonia, and to a lesser extent in primary spermatocytes even in the absence of Ago3. Consistently, piRNAs from ago3 mutant testes also exhibit the ping-pong signature, confirming that a non-canonical ping-pong cycle is acting during spermatogenesis. Our study provides a developmental dimension to the piRNA pathway and uncovers a new mechanism used in the male germline to silence transposons. The difference in piRNA from spermatogonia and primary spermatocyte stages was studied by comparing small RNAs from bam and bgcn mutant testis, which represent spermatogonia stages with the small RNAs from apex removed can and sa testis, representing primary spermatocyte stages. In the study we also studied effect of loss of Piwi family proteins Aub and Ago3, which have different spatial expression during male germline development.
2016-08-10 | E-GEOD-69417 | biostudies-arrayexpress
Project description:The piRNA biogenesis machinery localizes to phase-separated nuage granules, but nuage function is not well understood. We therefore assayed nuage composition, piRNA expression, and transposon silencing in Drosophila mutants that disrupt piRNA precursor production and nuclear export, ping-pong amplification, and phased piRNA biogenesis. These mutations destabilize the genome and activate Chk2 signaling, and chk2/mnk double mutants were therefore analyzed in parallel. Aub and Vasa are required for ping-pong amplification, and Armi promotes phased piRNA processing. We show that Chk2 activation releases Aub and Vasa from nuage and that piRNA precursors are required for nuage localization of the ping-pong and phased biogenesis machinery. However, this analysis also indicates that Vasa, Aub, and Armi concentration in nuage is dispensable for piRNA production and transposon silencing, indicating that dispersed cytoplasmic proteins can drive these processes. We speculate that nuage sequesters silencing effectors, which are released by Chk2 in response to transposon mobilization.
2026-02-24 | GSE236035 | GEO
Project description:PIWI proteins and their associated piRNAs protect germ cells from the activity of mobile genetic elements. Two classes of piRNAs—primary and secondary—are defined by their mechanisms of biogenesis. Primary piRNAs are processed directly from transcripts of piRNA cluster loci, whereas secondary piRNAs are generated in an adaptive amplification loop, termed the ping-pong cycle. In mammals, piRNA populations are dynamic, shifting as male germ cells develop. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, the piRNA population is transposon-poor and largely restricted to primary piRNAs derived from pachytene piRNA clusters. The transition from the embryonic to the adult piRNA pathway is not well understood. Here we show that RNF17 shapes adult meiotic piRNA content by suppressing the production of secondary piRNAs. In the absence of RNF17, ping-pong occurs inappropriately in meiotic cells. Ping-pong initiates piRNA responses against not only transposons but also protein-coding genes and long noncoding RNAs, including genes essential for germ cell development. Thus, the sterility of Rnf17 mutants may be a manifestation of a small RNA-based autoimmune reaction.
2014-12-17 | GSE53915 | GEO
Project description:PIWI proteins and their associated piRNAs protect germ cells from the activity of mobile genetic elements. Two classes of piRNAs—primary and secondary—are defined by their mechanisms of biogenesis. Primary piRNAs are processed directly from transcripts of piRNA cluster loci, whereas secondary piRNAs are generated in an adaptive amplification loop, termed the ping-pong cycle. In mammals, piRNA populations are dynamic, shifting as male germ cells develop. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, the piRNA population is transposon-poor and largely restricted to primary piRNAs derived from pachytene piRNA clusters. The transition from the embryonic to the adult piRNA pathway is not well understood. Here we show that RNF17 shapes adult meiotic piRNA content by suppressing the production of secondary piRNAs. In the absence of RNF17, ping-pong occurs inappropriately in meiotic cells. Ping-pong initiates piRNA responses against not only transposons but also protein-coding genes and long noncoding RNAs, including genes essential for germ cell development. Thus, the sterility of Rnf17 mutants may be a manifestation of a small RNA-based autoimmune reaction.
2014-12-17 | GSE53919 | GEO
Project description:RNF17 referees ping-pong in mouse testes [smallRNAseq]
| PRJNA233963 | ENA
Project description:RNF17 referees ping-pong in mouse testes [RNAseq]
| PRJNA233959 | ENA
Project description:In animals, the piRNA pathway preserves the integrity of gametic genomes, guarding them against the activity of mobile genetic elements. This innate immune mechanism relies on distinct genomic loci, termed piRNA clusters, to provide a molecular definition of transposons, enabling their discrimination from genes. piRNA clusters give rise to long, single-stranded precursors which are processed into primary piRNAs through an unknown mechanism. These can engage in an adaptive amplification loop, the ping-pong cycle, to optimize the content of small RNA populations via the generation of secondary piRNAs. Many proteins have been ascribed functions in either primary biogenesis or the ping-pong cycle, though for the most part the molecular functions of proteins implicated in these pathways remain obscure. Here, we link shutdown, a gene previously shown to be required for fertility in Drosophila, to the piRNA pathway. Analysis of knockdown phenotypes in both the germline and somatic compartments of the ovary demonstrate important roles for shutdown in both primary biogenesis and the ping-pong cycle. shutdown is a member of the FKBP family of immunophilins. Shu contains domains implicated in peptidyl-prolyl cis-trans isomerase activity and in the binding of HSP90-family chaperones, though the relevance of these domains to piRNA biogenesis is unknown.
2012-07-01 | GSE38090 | GEO
Project description:Germline-specific Piwi-interacting RNAs (piRNAs) protect the genome against selfish genetic elements and are essential for fertility in animals. piRNAs targeting active transposons are amplified by a feed-forward loop known as the Ping-pong cycle, which links endonucleolytic slicing of target RNAs by Piwi proteins to biogenesis of new piRNAs. However, the biochemical framework for this pathway remains elusive. Here, we describe the identification of a transient Amplifier complex mediating the biogenesis of secondary piRNAs in insect cells. This complex is nucleated by the RNA helicase Vasa and contains the two Piwi proteins participating in the Ping-pong loop, the Tudor protein Qin/Kumo and antisense piRNA guides. These components assemble on the surface of Vasa's helicase domain, which functions as an RNA clamp to anchor Amplifier onto transposon transcripts. We show that ATP-dependent RNP remodelling by Vasa facilitates the transfer of 5'-sliced piRNA precursors between the Ping-pong partners, and failure to achieve this results in Drosophila female sterility.
2014-06-04 | GSE57420 | GEO