The expanding role of m6A RNA modification in plant-virus dynamics: friend, foe, or both?

Abstract

N⁶-methyladenosine (m⁶A), the most prevalent internal mRNA modification, regulates plant development and stress responses through modulating various mRNA metabolic processes and epigenetic effects. Although well studied in animals, its roles in plant-virus interactions have only recently begun to be elucidated. Multiple plant viruses carry m⁶A modifications on their RNAs, validated by MeRIP-seq, LC-MS/MS, and direct RNA sequencing. Viral RNAs acquire m⁶A through the recruitment or relocalization of host methyltransferase complexes, which is often mediated by viral proteins. Functionally, m⁶A can restrict infection by promoting viral RNA decay via YTH-domain readers and RNA surveillance pathways, or alternatively stabilize viral RNAs to enhance replication and systemic spread. In turn, viruses disrupt the functionality of host m⁶A machinery to promote infection. Moreover, viral infection reprograms host m⁶A homeostasis, altering methylation landscapes in immune and hormone pathways. These findings establish m⁶A as a dynamic epitranscriptomic switch in plant-virus interactions, with promising implications for antiviral strategies and crop improvement.