Unique features of the m6A methylome in Arabidopsis thaliana

Abstract

Recent discoveries of reversible N⁶-methyladenosine (m⁶A) methylation on messenger RNA (mRNA) and mapping of m⁶A methylomes in mammals and yeast have revealed potential regulatory functions of this RNA modification. In plants, defects in m⁶A methyltransferase cause an embryo-lethal phenotype, suggesting a critical role of m⁶A in plant development. Here, we profile m⁶A transcriptome-wide in two accessions of Arabidopsis thaliana and reveal that m⁶A is a highly conserved modification of mRNA in plants. Distinct from mammals, m⁶A in A. thaliana is enriched not only around the stop codon and within 3′-untranslated regions, but also around the start codon. Gene ontology analysis indicates that the unique distribution pattern of m⁶A in A. thaliana is associated with plant-specific pathways involving the chloroplast. We also discover a positive correlation between m⁶A deposition and mRNA abundance, suggesting a regulatory role of m⁶A in plant gene expression.