[RNA methylation: regulations and mechanisms]

Epigenetic modifications include the chemical modifications on DNA, RNA and proteins characterized by altered gene expression and function without any changes in the gene sequence. In addition to well-established DNA and protein epigenetic modifications, the reversible RNA methylation has led the third wave of studies in the epigenetic field. RNA has more than 100 chemical modifications, among which methylation is the major type. The identification of catalyzing enzymes for RNA methylation and the development of high-throughput detection technologies for RNA modification at the transcriptomic level are the prerequisites for revealing the regulatory role of RNA methylation in gene expression and biological functions. In this review, we summarize the recent frontier in RNA methylation-mediated epitranscriptomics from our and other laboratories, with emphasis on the discoveries of RNA modification demethylase , methyltransferase and binding protein as well as the illustration of regulatory roles of RNA methylation modification in hematopoietic stem cell differentiation, spermatogenesis, brain development and other pivotal life processes. These findings have shown that RNA methylation is just as reversible as DNA methylation, and opened up a novel field in RNA methylation-mediated epitranscriptomics, which appends a new layer of epigenetic regulation to the central genetic dogma.