Transcriptome-wide mapping of m6A in bovine oocytes and preimplantation embryos by SAC-seq

However, the m6A dynamics at single-nucleotide resolution during preimplantation development has not been characterized, and the function of m6A marks in specific transcripts remain largely unexplored. Here, by using SAC-seq, we overcome the limitation of antibody-based m6A profiling and define m6A landscapes in bovine oocytes and pre-implantation embryos at unprecedented level.

Notably, we identify a specific m6A site on RPL12 (m6A-RPL12), which was highly methylated at the 8-cell stage. m6A-RPL12 deficient leads to reduced protein synthesis, disrupted expression of translation-related genes, and impaired zygotic genome activation and blastocyst formation. Supplementation with wild-type RPL12 mRNA failed to rescue the developmental arrest, indicating that m6A regulation extends beyond transcript abundance.