RNF17 referees ping-pong in mouse testes [smallRNAseq]
Ontology highlight
ABSTRACT: In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters. Examination of small RNA profile in heterozygous and homozygous RNF17 adult testes, pachytene or round spermatid sorted cells
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters1-6. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters. Examination of small RNAs isolated from MIWI and MILI IPs of heterozygous and homozygous RNF17 adult testes
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters. Refer to individual Series
Project description:The genome of male germ cells is actively transcribed during spermatogenesis to produce phase-specific protein coding mRNAs and a considerable amount of different non-coding RNAs. Ribonucleoprotein (RNP) granule-mediated RNA regulation provides a powerful means to secure the quality and correct expression of the requisite transcripts. Haploid spermatids are characterized by a unique, unusually large cytoplasmic granule, the chromatoid body (CB), that emerges during the switch between the meiotic and post-meiotic phases of spermatogenesis. To better understand the role of the CB in male germ cell differentiation, we isolated CBs from mouse testes and revealed its full RNA and protein composition. We showed that the CB is mainly composed of RNA-binding proteins and other proteins involved RNA regulation. The CB was loaded with RNA, including pachytene piRNAs, a diverse set of mRNAs and a number of uncharacterized long non-coding transcripts. The CB was demonstrated to accumulate nascent RNA during all the steps of round spermatid differentiation. Our results revealed the CB as a large germ cell -specific RNP platform that is involved in the control of the highly complex transcriptome of haploid male germ cells. Small RNA profiling of purified chromatoid body, each steps of chromatoid body purification, and sortred round spermatid cells
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters. Examination of 5'RACE in heterozygous and homozygous RNF17 adult testes or MIWI/MILI immunoprecipitates
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters. Examination of transcriptom in heterozygous and homozygous RNF17 adult testes and RNF17 immunoprecipitates
Project description:We have found that oncogenic Ras combined with loss of the Hippo tumour-suppressor pathway reactivates a primary piRNA pathway in Drosophila somatic cells, coincident with oncogenic transformation. In these cells, Piwi becomes loaded with piRNAs derived from generative loci, which are normally restricted to either the germline or the somatic follicle cells. Negating the pathway leads to increases in the expression of a wide variety of transposons and also to altered expression of some protein coding genes. This correlates with a reduction in the proliferation of the transformed cells in culture, suggesting that at least in this context, the piRNA pathway may play a functional role in cancer. Small RNAs cloned from whole cells, piwi-bound small RNAs and long RNA-Seq were performed in wts-RNAi;RasV12 cells to identify piRNAs and gene expression and compared to RasV12 cells, somatic OSS cells, and germline UAS-wts-RNAi;UAS-RasV12 control ovaries. After knock-down of several components of the piRNA machinery in WRR-1 cells (piwi, zuchini, armitage, aubergine, argonaute3) and GFP and/or dsRED control knock-downs, small RNAs were cloned and gene expression profiles (RNA-Seq) were established.
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters1-6. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters.
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters.
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly 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 (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters.
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.