The m6A epitranscriptome and the emerging role of m6Am: Molecular hubs for regulating abiotic stress tolerance in cotton

RNA modifications, especially N6-methyladenosine (m6A) and N6,2′-O-dimethyladenosine (m6Am), are emerging as important regulators of gene expression during plant responses to abiotic stress. In cotton (Gossypium hirsutum), m6A improves transcript stability and regulates critical stress signals, including abscisic acid and calcium, which increase drought tolerance. Although m6Am is less studied, it is highly intertwined with m6A and may therefore play a significant role, despite not having been fully explored. The current review is devoted to the chemical characteristics, enzyme regulation and functional activity of m6A and m6Am in the reaction of cotton to abiotic stress. It also presents the recent developments in high-resolution mapping and functional validation methods. It explains how RNA methylation can be utilized in molecular breeding strategies to enhance the stress resilience of cotton. In general, RNA methylation is a dynamic process of epitranscriptomics that is essential in cotton adaptation to the conditions of stress.