Reading m6A marks in mRNA: A potent mechanism of gene regulation in plants

Abstract

Modifications to RNA have recently been recognized as a pivotal regulator of gene expression in living organisms. More than 170 chemical modifications have been identified in RNAs, with N⁶-methyladenosine (m⁶A) being the most abundant modification in eukaryotic mRNAs. The addition and removal of m⁶A marks are catalyzed by methyltransferases (referred to as “writers”) and demethylases (referred to as “erasers”), respectively. In addition, the m⁶A marks in mRNAs are recognized and interpreted by m⁶A-binding proteins (referred to as “readers”), which regulate the fate of mRNAs, including stability, splicing, transport, and translation. Therefore, exploring the mechanism underlying the m⁶A reader-mediated modulation of RNA metabolism is essential for a much deeper understanding of the epigenetic role of RNA modification in plants. Recent discoveries have improved our understanding of the functions of m⁶A readers in plant growth and development, stress response, and disease resistance. This review highlights the latest developments in m⁶A reader research, emphasizing the diverse RNA-binding domains crucial for m⁶A reader function and the biological and cellular roles of m⁶A readers in the plant response to developmental and environmental signals. Moreover, we propose and discuss the potential future research directions and challenges in identifying novel m⁶A readers and elucidating the cellular and mechanistic role of m⁶A readers in plants.