N6-methyladenosine regulates maternal RNA maintenance in oocytes and timely RNA decay during mouse maternal-to-zygotic transition

Abstract N6-methyladenosine (m6A) on RNA and its regulatory components play critical roles in various developmental processes in mammals. However, the landscape and function of m6A in early embryos remain unclear due to limited materials. Current methods typically need total RNA greater than microgram amount to map m6A positions, which prevents us from revealing the crucial role of m6A in early embryonic development in mice. Here, we developed an ultra-low-input(ULI) MeRIP-seq method to reveal the transcriptome-wide m6A landscape in limited biological materials which contain as low as 50ng total RNA. Antibody-based ULI MeRIP-seq reveal the high efficiency of immunoprecipitation and reduced RNA loss during the experiments. Sequencing data reveal the m6A enrichment of mRNAs as well as non-coding RNAs which are highly recapitulated the results generated by 2µg of total RNA.To further promote the application on limited RNA materials, we describe a step-by-step protocol about how to construct a successful ULI MeRIP-seq library.