N6-Methyladenosine Sequencing Highlights the Involvement of mRNA Methylation in Oocyte Meiotic Maturation and Embryo Development by Regulating Translation in Xenopus laevis.
During the oogenesis of Xenopus laevis, oocytes accumulate maternal materials for early embryo development. As the transcription activity of the oocyte is silenced at the fully grown stage and the global genome is reactivated only by the mid-blastula embryo stage, the translation of maternal mRNAs accumulated during oocyte growth should be accurately regulated. Previous evidence has illustrated that the poly(A) tail length and RNA binding elements mediate RNA translation regulation in the oocyte. Recently, RNA methylation has been found to exist in various systems. In this study, we sequenced the N6-methyladenosine (m6A) modified mRNAs in fully grown germinal vesicle-stage and metaphase II-stage oocytes. As a result, we identified 4207 mRNAs with m6A peaks in germinal vesicle-stage or metaphase II-stage oocytes. When we integrated the mRNA methylation data with transcriptome and proteome data, we found that the highly methylated mRNAs showed significantly lower protein levels than those of the hypomethylated mRNAs, although the RNA levels showed no significant difference. We also found that the hypomethylated mRNAs were mainly enriched in the cell cycle and translation pathways, whereas the highly methylated mRNAs were mainly associated with protein phosphorylation. Our results suggest that oocyte mRNA methylation can regulate cellular translation and cell division during oocyte meiotic maturation and early embryo development.
From the State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China and.
Shu-Tao
ST
Qi
the College of Animal Science and Technology, Qingdao Agricultural University, Qingdao 266109, China.
Jun-Yu
JY
Ma
From the State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China and.
Zhen-Bo
ZB
Wang
From the State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China and.
Lei
L
Guo
From the State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China and.
Yi
Y
Hou
From the State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China and sunqy@ioz.ac.cn.|the College of Animal Science and Technology, Qingdao Agricultural University, Qingdao 266109, China.
Qing-Yuan
QY
Sun
D000241:Adenosine / Q000031:analogs & derivatives* / Q000378:metabolism; D000818:Animals; D005260:Female; D018507:Gene Expression Regulation, Developmental; D008297:Male; D008540:Meiosis; D009865:Oocytes / Q000254:growth & development* / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D029867:Xenopus Proteins / Q000235:genetics* / Q000378:metabolism; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*
D012333:RNA, Messenger; D029867:Xenopus Proteins; C010223:N-methyladenosine; D000241:Adenosine
RNA methylation; embryo; meiosis; oocyte; translation