Characteristics and functions of DNA N(6)-methyladenine in embryonic chicken muscle development.

DNA N(6)-methyladenine (DNA-6mA) is a new epigenetic mark in eukaryotes, the distribution and functions of which in genomic DNA remain unknown. Although recent studies have suggested that 6mA is present in multiple model organisms and is dynamically regulated during development, the genomic features of 6mA in avian species have yet to be elucidated. 6mA immunoprecipitation sequencing approach was used to analysis the distribution and function of 6mA in the muscle genomic DNA during embryonic chicken development. 6mA immunoprecipitation sequencing was combined with transcriptomic sequencing to reveal the role of 6mA in the regulation of gene expression and to explore possible pathways by which 6mA is involved in muscle development. We here provide evidence that 6mA modification exists widely throughout the chicken genome, and show preliminary data regarding genome-wide distribution of this epigenetic mark. Gene expression was shown to be inhibited by 6mA modification in promoter regions. In addition, the promoters of some genes related to development were modified by 6mA, indicating that 6mA may be involved in embryonic chicken development. Furthermore, 6mA may participate in muscle development and immune function by regulating HSPB8 and OASL expression. Our study improves our understanding of the distribution and function of 6mA modification in higher organisms and provide new information about differences between mammals and other vertebrates. These findings demonstrate an epigenetic role for 6mA in gene expression and potential involvement in chicken muscle development. Furthermore, the results suggest a potential epigenetic role for 6mA in avian embryonic development.