Abstract：N6-methyladenosine (m6A), the predominantly internal epigenetic modification in eukaryotic RNA, plays an important role in a variety of physiological and pathological processes. With the rapid development of high-throughput sequencing and single-base resolution detection technologies, an increasing number of m6A modification-related proteins and their target genes have been successfully identified in aquatic animals, and the corresponding regulatory functions and molecular mechanisms have gradually been clarified. This review systematically summarized the functions and mechanisms of m6A modification in aquatic animals such as reptiles, amphibians, fish, crustaceans, mollusks, and echinoderms, which aim to reveal the functional conservation and species specificity of this modification during evolution, and to provide potential molecular targets and biomarkers for the growth and development, stress-resistant breeding, and disease control of aquatic animals.
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