[Modified nucleosides in eukaryotic messenger RNAs and their roles in developmental regulation]

Epigenetic nucleoside modifications are critical for the stability and translational efficiency of messenger RNA. Depending on the organism, developmental stage, and tissue/organ investigated, the location and abundance of these nucleoside modifications may differ, which in turn influence the splicing event, half-life time of mature mRNA, as well as translation efficiency. Among the approximately 170 RNA nucleoside modifications, only a handful are found in mRNAs. The low abundance and high organ specificity make it a challenging work to study the role of each specific mRNA nucleoside modification. However, with the technical advances in recent years, including meRIP, great progress has been achieved, especially on the function of m⁶A and m⁵C epigenetic markers in eukaryotes. This review summarizes recent progress on nucleoside modifications of messenger RNAs, on their distribution on transcripts and their role in regulating growth anddevelopment. We also discuss the technical bottleneck and key issues for future investigation.