Dataset Information

USP16-mediated Histone H2A Lysine-119 Deubiquitination during Oocyte Maturation is a Prerequisite for Zygotic Genome Activation

ABSTRACT: Maternal-to-zygotic transition (MZT) is the first and key step in the control of animal development and is intimately related to changes of chromatin structure and histone modifications. Mono-ubiquitination of histone H2A at lysine-119 (H2AK119ub1), an important epigenetic modification in regulating chromatin configuration and function, is primarily catalyzed by polycomb repressive complex 1 (PRC1) and contributes to resistance to transcriptional reprogramming in mouse embryos. In this study, the genome-wide dynamic distribution of H2AK119ub1 during MZT in mice was investigated by chromosome immunoprecipitation and sequencing. The results indicated that H2AK119ub1 accumulated in fully grown oocytes, enriched at the transcriptional start sequences (TSSs) of maternal genes, but was promptly removed after meiotic resumption, particularly at the TSSs of early zygotic genes, by a previously unidentified mechanism. Genetic evidences indicated that ubiquitin-specific peptidase 16 (USP16) is the major deubiquitinase of H2AK119ub1 in mouse oocytes. Conditional knockout of Usp16 in oocytes did not impair their survival, growth, andor meiotic maturation. However, oocytes lacking USP16 were unable to undergo zygotic genome activation or gain developmental competence after fertilization, due to high levels of H2AK119ub1 deposition on the zygotic genomes. Taken together, this study indicates that H2AK119ub1 is erased during oocyte maturation by an USP16-dependent mechanism, which ensures zygotic genome reprogramming and transcriptional activation of essential early zygotic genes.

ORGANISM(S): Mus musculus

PROVIDER: GSE154412 | GEO | 2022/06/05

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Background: Metazoan embryos undergo a maternal-to-zygotic transition (MZT) during which a subset of maternal gene products is eliminated and the zygotic genome becomes transcriptionally active. RNA-binding proteins (RBPs) and the microRNA-induced silencing complex (miRISC) â of which Argonaute 1 (AGO1) is a key component in Drosophila â target maternal mRNAs for degradation. The Drosophila Smaug, Brain tumor (BRAT) and Pumilio (PUM) RBPs direct the degradation of maternal mRNAs. Here we elucidate Smaugâs roles in regulation of miRNAs and miRISC during the MZT. Results: By global analysis of small RNAs at several stages during the MZT, we show that the vast majority of all miRNA species encoded by the Drosophila genome (85%) are expressed during the MZT. Whereas a subset of these miRNAs is loaded into oocytes by the mother and stays at constant levels during the MZT, dozens of miRNA species are either newly synthesized or re-expressed in the early embryo. Loss of Smaug has a profound effect on miRNAsÂ but little effect on piRNAs or siRNAs. Smaug is required for production of new miRNAs during the MZT; Smaug-bound AGO1 reflects the constellation and abundance of the miRNAs present in early embryos; and Smaug is required for the increase in AGO1 protein levels that occurs during the MZT. As a consequence of low miRISC activity in smaug mutants, maternal mRNAs that are normally targeted for degradation by zygotic miRNAs fail to be cleared. BRAT and PUM share target mRNAs with miRISC during the MZT while the miR-309 miRNA family coregulates targets of BRAT but not PUM. Conclusions: Smaug controls the MZT through direct targeting of a subset of maternal mRNAs for degradation and, indirectly, through production and function of miRNAs and miRISC, which control clearance of a distinct subset of maternal mRNAs. BRAT and/or PUM function together with miRISC during the latter process. With respect to miRISC-dependent transcript degradation, Smaug is required (1) for the synthesis of miRNAs, (2) for synthesis and stabilization of AGO1, and (3) for action of AGO1 in association with its bound miRNAs. In smaug mutants a large number of maternal mRNAs persist and the MZT fails. Examination of miRNA expresssion at different time points in wild type and smuag mutant early embryos .

Dataset Information

USP16-mediated Histone H2A Lysine-119 Deubiquitination during Oocyte Maturation is a Prerequisite for Zygotic Genome Activation

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure