Bisection of the X Chromosome Disrupts the Initiation of Chromosome Silencing during Meiosis in Caenorhabditis elegans
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA721425 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR14215362.fastq.gz | Fastqsanger.gz | |||
| SRR14215363.fastq.gz | Fastqsanger.gz | |||
| SRR14215364.fastq.gz | Fastqsanger.gz | |||
| SRR14215365.fastq.gz | Fastqsanger.gz | |||
| SRR14215366.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 8 |
Similar Datasets
Project description:During meiosis, gene expression is silenced in aberrantly unsynapsed chromatin and in heterogametic sex chromosomes. Initiation of sex chromosome silencing is disrupted in meiocytes with sex chromosome-autosome translocations. To determine whether this is due to aberrant synapsis or loss of continuity of sex chromosomes, we engineered Caenorhabditis elegans with non-translocated, bisected X chromosomes. In early meiocytes of mutant males and hermaphrodites, X segments were enriched with euchromatin assembly markers and active RNA polymerase II staining, indicating active transcription. Analysis of RNA-seq data showed that genes from the X chromosome were upregulated in gonads of mutant worms. Contrary to previous models, which predicted that any unsynapsed chromatin is silenced during meiosis, our data indicate that unsynapsed X segments are transcribed. Therefore, our results suggest that sex chromosome chromatin has a unique character that facilitates its meiotic expression when its continuity is lost, regardless of whether or not it is synapsed.
2021-05-24 | GSE171938 | GEO
Project description:During meiosis, gene expression is silenced in aberrantly unsynapsed chromatin and in heterogametic sex chromosomes. Initiation of sex chromosome silencing is disrupted in meiocytes with sex chromosome-autosome translocations. To determine whether this is due to aberrant synapsis or loss of continuity of sex chromosomes, we engineered Caenorhabditis elegans nematodes with non-translocated, bisected X chromosomes. In early meiocytes of mutant males and hermaphrodites, X segments are enriched with euchromatin assembly markers and active RNA polymerase II staining, indicating active transcription. Analysis of RNA-seq data showed that genes from the X chromosome are upregulated in gonads of mutant worms. Contrary to previous models, which predicted that any unsynapsed chromatin is silenced during meiosis, our data indicate that unsynapsed X segments are transcribed. Therefore, our results suggest that sex chromosome chromatin has a unique character that facilitates its meiotic expression when its continuity is lost, regardless of whether or not it is synapsed.
| S-EPMC8355143 | biostudies-literature
Project description:During Caenorhabditis elegans oocyte meiosis, a multi-protein complex localised between homologous chromosomes, the ring complex (RC), promotes chromosome congression through the action of the chromokinesin KLP-19. While some RC components are known, the mechanism of RC assembly has remained obscure. A germline-specific screen identified KLP-19 as a SUMO substrate in vivo and we found that the SUMO E3 ligase GEI-17/PIAS is required for KLP-19 recruitment to the RC. Additionally, KLP-19 is efficiently sumoylated in vitro in a GEI-17-dependent manner. Further biochemical analysis showed that KLP-19 and GEI-17 are efficiently modified by SUMO and that GEI-17 and another RC component, the kinase BUB-1, can interact non-covalently with SUMO. While SUMO conjugation is required for RC assembly, we also provide evidence consistent with non-covalent SUMO interactions contributing to RC assembly in vivo. Our results highlight the importance of sumoylation and non-covalent SUMO interaction in regulating dynamic protein complex assembly during oocyte meiosis.
2020-10-15 | PXD005202 | Pride
Project description:Meiosis produces gametes through a specialised, two-step cell division, which is highly error-prone in humans. Reductional meiosis I, where maternal and paternal chromosomes (homologs) segregate, is followed by equational meiosis II, where sister chromatids separate. Uniquely during meiosis I, sister kinetochores are monooriented and pericentromeric cohesin is protected. Here, we demonstrate that these key adaptations for reductional chromosome segregation are achieved through separable control of multiple kinases by the meiosis I-specific budding yeast Spo13 protein. Recruitment of Polo kinase to kinetochores directs monoorientation, while, independently, cohesin protection is achieved by controlling the effects of cohesin kinases. Therefore, reductional chromosome segregation, the defining feature of meiosis, is established by multifaceted kinase control by a master regulator. The recent identification of Spo13 orthologs, fission yeast Moa1 and mouse MEIKIN, suggests that kinase coordination by a master meiosis I regulator may be a general feature in the establishment of reductional chromosome segregation.
2019-11-13 | PXD012627 | Pride
Project description:As a serine/threonine phosphatase, protein phosphatase 2A (PP2A) is essential in numerous physiological processes. Our previously study confirmed PP2A dysfunction can cause azoospermia by generating catalytic subunit of PP2A (Ppp2ca) conditional knockout (CKO) in C57BL/6J mice. Here, we further explored the possible mechanisms by focusing on meiosis initiation and spermatogenesis. The deficiency of Ppp2ca in germ cells conspicuously disturbed spermatogonial differentiation and lead to pachytene arrest, accompanied by defects in programmed double-strand break (DSB) repair and meiotic sex chromosome inactivation (MSCI). Furthermore, Ppp2ca-deficient spermatocytes exhibited abnormal agglutination and cohesion complex degradation of chromosome, probably contributing to pachytene arrest. Our study demonstrates the irreplaceable role of PP2A in spermatogenesis and provide more evidences on azoospermia etiology.
2021-12-01 | GSE181132 | GEO
Project description:Male spermatogenesis is an essential and complex developmental process with the purpose to gain totipotency and allow a whole new organism to develop upon fertilization. While single-gene based studies have provided insights into the mechanisms at work, global profiling is clearly required to deconvolute these processes. Here, by isolating highly enriched mouse meiotic cell populations, we report a comprehensive gene expression map of mammalian meiosis. Our data reveal in unique details the dynamic of fundamental expression patterns such as the global chromosome X inactivation and reactivation allowing to precisely dissect this unique process. It also reveals a rapid global expression switch at the initiation of the long pachytene stage reminiscent and coincident with the commitment to meiosis observed in budding yeast. Overall, this meiotic atlas provides an exhaustive blueprint and resource for deconvoluting mammalian gametogenesis and meiosis.
2010-12-16 | GSE21447 | GEO
Project description:Male spermatogenesis is an essential and complex developmental process with the purpose to gain totipotency and allow a whole new organism to develop upon fertilization. While single-gene based studies have provided insights into the mechanisms at work, global profiling is clearly required to deconvolute these processes. Here, by isolating highly enriched mouse meiotic cell populations, we report a comprehensive gene expression map of mammalian meiosis. Our data reveal in unique details the dynamic of fundamental expression patterns such as the global chromosome X inactivation and reactivation allowing to precisely dissect this unique process. It also reveals a rapid global expression switch at the initiation of the long pachytene stage reminiscent and coincident with the commitment to meiosis observed in budding yeast. Overall, this meiotic atlas provides an exhaustive blueprint and resource for deconvoluting mammalian gametogenesis and meiosis. 10- to 16-week-old male C57BL/6 x DBA/2J F1 testis were used for sorting multiple meiotic fractions. These samples were used for subsequent RNA purification, labeling and hybridization to Affymetrix arrays. 1-4 biological replicates per fraction.
2010-12-16 | E-GEOD-21447 | biostudies-arrayexpress
Project description:Meiosis is a specialized form of cell division essential for sexual reproduction. The unique cellular events of meiosis have been extensively studied in model eukaryotes, including mammals. In mammals, the molecular and cellular changes that germ cells must undergo to transition from mitotic spermatogonia to meiotic spermatocytes remain largely undefined. Retinoic acid (RA) has been proposed as the meiosis inducing substance (MIS) required for female and male meiotic initiation. However, evidence for this presumption is based on studies of fetal gonads – meiosis is initiated in fetal ovaries but suppressed in fetal testes. Critically, the requirement for RA in meiosis has never been formally tested because germ cell differentiation and meiotic initiation in the fetal ovary are temporally inseparable. Using the postnatal mouse testis, where differentiation and meiotic initiation are temporally distinct (8.6 days apart), we test the hypothesis that RA is dispensable for initiation and progression through meiosis. Complementary in vivo experimental models were designed to address the hypothesis. In the first, “RA-sufficient” (RA-suf) model, spermatogenesis was synchronized by administration of potent and selective RA synthesis inhibitor; as a result, testes contained only undifferentiated spermatogonia. Then, the inhibitor was discontinued, and mice were given a single dose of exogenous RA to initiate spermatogonial differentiation. Germ cells completed differentiation, entered and completed meiosis, and formed haploid gametes at predicted timepoints. In the second, “RA-deficient” (RA-def) model, mice were treated as above, except the inhibitor was administered continuously. The lack of testicular RA in this model was confirmed in multiple ways, including assessment of RA-responsive gene expression, in vitro serum-free cultures, and dose-response experiments. To our surprise, germ cells in RA-def testes completed differentiation, underwent meiotic DNA replication, completed the landmark cytological processes of meiosis, and formed postmeiotic haploid spermatids, all on the predicted timeline of the RA-suf model. To define the effect of RA-deficiency on gene expression during meiotic initiation, large, highly enriched populations of premeiotic spermatogonia from RA-suf mice, and meiotic preleptotene spermatocytes from both models were FACS-isolated and subjected to bulk RNA-seq. Interestingly, analyses revealed few significant differences in expression of characteristic meiotic genes at the mRNA level. However, genes that were significantly different between RA-suf and RA-def preleptotene spermatocytes were associated with spermiogenesis functions. Taken together, our data reveal that, after initiating spermatogonial differentiation, RA is dispensable for initiation, progression through, and completion of meiosis in the male germline.
2023-07-03 | GSE194376 | GEO
Project description:Catalytic Subunit of Protein Phosphatase 2A (PP2Ac) Influences the Meiosis Initiation During Spermatocyte Meiosis Prophase I
| PRJNA750761 | ENA
Project description:During meiosis, a single round of DNA replication is followed by two consecutive rounds of nuclear divisions called meiosis I and meiosis II. In meiosis I, homologous chromosomes segregate, while sister chromatids remain together. Determining how this unusual chromosome segregation behavior is established is central to understanding germ cell development. Here we show that preventing microtubule-kinetochore interactions during premeiotic S phase and prophase I is essential for establishing the meiosis I chromosome segregation pattern. Premature interactions of kinetochores with microtubules transform meiosis I into a mitosis-like division by disrupting two key meiosis I events: coorientation of sister kinetochores and protection of centromeric cohesin removal from chromosomes. Furthermore we find that restricting outer kinetochore assembly contributes to preventing premature engagement of microtubules with kinetochores. We propose that inhibition of microtubule-kinetochore interactions during premeiotic S phase and prophase I is central to establishing the unique meiosis I chromosome segregation pattern.
2012-10-05 | GSE41339 | GEO