N6-Methyladenosine and G-Quadruplex in Bacterial Messenger RNA

The modification and secondary structure of messenger RNA (mRNA) are tightly associated with its functions to control many intracellular events and biological processes. In the past decade, rapid development of high-resolution sequencing techniques enables the detection of chemical modifications and structures onto various types of RNA, especially the low-abundance mRNA. Unlike the rapid progress made in eukaryotes, studies on the modifications of prokaryotic mRNA remain limited. Here, we review bacterial N6-methyladenosine (m⁶A) and RNA G-quadruplex (rG4), which are two recently studied mRNA modifications or structures in bacterial mRNA. This chapter includes their occurrences, topological patterns, and potential regulatory functions in bacterial mRNA. Although the role of m⁶A in bacterial mRNA is still illusive, experiments have shown that rG4 can regulate gene expression at the post-transcriptional level. We also discuss the different characteristic s of m⁶A and rG4 between eukaryotic cells and bacteria.