Dual Roles of m⁶A Modification: Orchestrating Development and Abiotic Stress Resilience in Plants

RNA N⁶-methyladenosine (m⁶A) is a prevalent epitranscriptomic modification that governs plant growth, development, and environmental adaptation. This review synthesizes recent advances in understanding the molecular mechanisms and biological functions of m⁶A in plants. The m⁶A landscape is dynamically regulated by methyltransferases (writers), demethylases (erasers), and m⁶A-binding proteins (readers), which collectively influence mRNA stability, translation efficiency, alternative polyadenylation (APA), and chromatin crosstalk. Functionally, m⁶A integrates diverse developmental processes-including embryogenesis, organogenesis, flowering, fruit ripening, and leaf senescence-with abiotic stress responses such as salt, drought, cold, and heat. Notably, m⁶A modification exhibits remarkable species-, cultivar-, and tissue-specific plasticity, enabling precise spatiotemporal gene regulation. Recent breakthroughs have revealed bidirectional crosstalk between m⁶A and histone modifications, forming a multi-layered regulatory network, while emerging concepts including phase separation, RNA structure dynamics, and stress memory further expand the functional repertoire of m⁶A. Despite significant progress, plant epitranscriptomics remains mechanistically underexplored, with critical gaps persisting in our understanding of translation initiation mechanisms, upstream regulatory signals controlling writers/erasers activities, and the functional significance of individual m⁶A sites. This review provided systematic insights into the complexity and specificity of m⁶A regulation in plants, offering a theoretical foundation for future efforts to decipher and ultimately manipulate this epitranscriptional layer for crop improvement.