RNA m6A modifications in mammalian gametogenesis and pregnancy.

The epitranscriptome is defined as the collection of post-transcriptional chemical modifications of RNA in a cell. RNA methylation refers to the chemical post-transcriptional modification of RNA by selectively adding methyl groups under the catalysis of a methyltransferase. The N6 methyladenosine (m6A) is one of the most common of the more than 100 known RNA modifications. Recent research has revealed that RNA m6A modifications are reversible. Additionally, m6A containing RNA can be selectively identified by immunoprecipitation followed by high-throughput sequencing (MeRIP-SEQ). These two developments have inspired a tremendous effort to unravel the biological role of m6A. The role of RNA m6A modifications in immune regulation, cell division, stem cell renewal, gametogenesis, embryonic development, and placental function has gradually emerged, which is of great significance for the study of post-transcriptional regulation of gene expression in reproductive biology. This review summarizes the current knowledge about RNA m6A modification in a variety of mammalian reproductive events.