Epitranscriptomic mRNA modifications governing plant stress responses: underlying mechanism and potential application

Plants inevitably encounter environmental adversities, including abiotic and biotic stresses, which significantly impede plant growth and reduce crop yield. Thus, fine-tuning the fate and function of stress-responsive RNAs is indispensable for plant survival under such adverse conditions. Recently, post-transcriptional RNA modifications have been studied as a potent route to regulate plant gene expression under stress. Among over 160 mRNA modifications identified to date, N-6-methyladenosine (m(6)A) in mRNAs is notable because of its multifaceted roles in plant development and stress response. Recent transcriptome-wide mapping has revealed the distribution and patterns of m(6)A in diverse stress-responsive mRNAs in plants, building a foundation for elucidating the molecular link between m(6)A and stress response. Moreover, the identification and characterization of m(6)A writers, readers and erasers in Arabidopsis and other model crops have offered insights into the biological roles of m(6)A in plant abiotic stress responses. Here, we review the recent progress of research on mRNA modifications, particularly m(6)A, and their dynamics, distribution, regulation and biological functions in plant stress responses. Further, we posit potential strategies for breeding stress-tolerant crops by engineering mRNA modifications and propose the future direction of research on RNA modifications to gain a much deeper understanding of plant stress biology.