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Argonaute 2 is a key regulator of maternal mRNA degradation in mouse early embryos.

ABSTRACT: In mammalian early embryos, the transition from maternal to embryonic control of gene expression requires timely degradation of a subset of maternal mRNAs (MRD). Recently, zygotic genome activation (ZGA)-dependent MRD has been characterized in mouse 2-cell embryo. However, in early embryos, the dynamics of MRD is still poorly understood, and the maternal factor-mediated MRD before and along with ZGA has not been investigated. Argonaute 2 (Ago2) is highly expressed in mouse oocyte and early embryos. In this study, we showed that Ago2-dependent degradation involving RNA interference (RNAi) and RNA activation (RNAa) pathways contributes to the decay of over half of the maternal mRNAs in mouse early embryos. We demonstrated that AGO2 guided by endogenous small interfering RNAs (endosiRNAs), generated from double-stranded RNAs (dsRNAs) formed by maternal mRNAs with their complementary long noncoding RNAs (CMR-lncRNAs), could target maternal mRNAs and cooperate with P-bodies to promote MRD. In addition, we also showed that AGO2 may interact with small activating RNAs (saRNAs) to activate Yap1 and Tead4, triggering ZGA-dependent MRD. Thus, Ago2-dependent degradation is required for timely elimination of subgroups of maternal mRNAs and facilitates the transition between developmental states.

SUBMITTER: Zhang JM

PROVIDER: S-EPMC7691497 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Argonaute 2 is a key regulator of maternal mRNA degradation in mouse early embryos.

Zhang Jia-Ming JM Hou Wei-Bo WB Du Jia-Wei JW Zong Ming M Zheng Kai-Lun KL Wang Wei-Jia WJ Wang Jia-Qiang JQ Zhang Heng H Mu Yan-Shuang YS Yin Zhi Z Ding Chun-Ming CM Sun Qing-Yuan QY Liu Zhong-Hua ZH Kong Qing-Ran QR

Cell death discovery 20201127 1

In mammalian early embryos, the transition from maternal to embryonic control of gene expression requires timely degradation of a subset of maternal mRNAs (MRD). Recently, zygotic genome activation (ZGA)-dependent MRD has been characterized in mouse 2-cell embryo. However, in early embryos, the dynamics of MRD is still poorly understood, and the maternal factor-mediated MRD before and along with ZGA has not been investigated. Argonaute 2 (Ago2) is highly expressed in mouse oocyte and early embry ...[more]

PMID: 33298889

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Argonaute 2 is a key regulator of maternal mRNA degradation in mouse early embryos.

Publications

Argonaute 2 is a key regulator of maternal mRNA degradation in mouse early embryos.

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