Physiologically relevant miRNAs in mammalian oocytes are rare and highly abundant

0554909 - ÚMG 2023 RIV US eng J - Journal Article
Kataruka, Shubhangini - Kinterová, Veronika - Horvat, Filip - Kulmann, Marcos Iuri Roos - Kaňka, Jiří - Svoboda, Petr
Physiologically relevant miRNAs in mammalian oocytes are rare and highly abundant.
Embo Reports. Roč. 23, č. 2 (2022), č. článku e53514. ISSN 1469-221X. E-ISSN 1469-3178
Institutional support: RVO:68378050 ; RVO:67985904
Keywords : miR-10b * miR-205 * miRNA * NanoLuc * oocyte
OECD category: Biochemistry and molecular biology
Impact factor: 7.7, year: 2022
Method of publishing: Open access
https://www.embopress.org/doi/full/10.15252/embr.202153514

miRNAs, similar to 22nt small RNAs associated with Argonaute (AGO) proteins, are important negative regulators of gene expression in mammalian cells. However, mammalian maternal miRNAs show negligible repressive activity and the miRNA pathway is dispensable for oocytes and maternal-to-zygotic transition. The stoichiometric hypothesis proposed that this is caused by dilution of maternal miRNAs during oocyte growth. As the dilution affects miRNAs but not mRNAs, it creates unfavorable miRNA:mRNA stoichiometry for efficient repression of cognate mRNAs. Here, we report that porcine ssc-miR-205 and bovine bta-miR-10b are exceptional miRNAs, which resist the diluting effect of oocyte growth and can efficiently suppress gene expression. Additional analysis of ssc-miR-205 shows that it has higher stability, reduces expression of endogenous targets, and contributes to the porcine oocyte-to-embryo transition. Consistent with the stoichiometric hypothesis, our results show that the endogenous miRNA pathway in mammalian oocytes is intact and that maternal miRNAs can efficiently suppress gene expression when a favorable miRNA:mRNA stoichiometry is established.
Permanent Link: http://hdl.handle.net/11104/0329524