Dynamic <scp>N⁶</scp>‐methyladenosine <scp>RNA</scp> modification regulates peanut resistance to bacterial wilt

Abstract

N⁶ -methyladenosine (m⁶ A) is the most abundant mRNA modification in eukaryotes and is an important regulator of gene expression as well as many other critical biological processes. However, the characteristics and functions of m⁶ A in peanut (Arachis hypogea L.) resistance to bacterial wilt (BW) remain unknown. Here, we analyzed the dynamic of m⁶ A during infection of resistant (H108) and susceptible (H107) peanut accessions with Ralstonia solanacearum (R. solanacearum), the causative agent of BW. Throughout the transcriptome, we identified 'URUAY' as a highly conserved motif for m⁶ A in peanut. The majority of differential m⁶ A located within the 3' untranslated region (UTR) of the transcript, with fewer in the exons. Integrative analysis of RNA-Seq and m⁶ A methylomes suggests the correlation between m⁶ A and gene expression in peanut R. solanacearum infection, and functional analysis reveals that m⁶ A-associated genes were related to plant-pathogen interaction. Our experimental analysis suggests that AhALKBH15 is an m⁶ A demethylase in peanut, leading to decreased m⁶ A levels and upregulation of the resistance gene AhCQ2G6Y. The upregulation of AhCQ2G6Y expression appears to promote BW resistance in the H108 accession.