Unique and Specific m⁶A RNA Methylation in Mouse Embryonic and Postnatal Cerebral Cortices

N⁶-methyladenosine (m⁶A)-mediated epitranscriptomic regulation is critical for various physiological processes. Genetic studies demonstrate that proper m⁶A-methylation is required for mouse brain development and function. Revealing landscapes of m⁶A-methylation in the cerebral cortex at different developmental stages will help to understand the biological meaning of epitranscriptomic regulation. Here, we depict the temporal-specific m⁶A-methylation status in mouse embryonic and postnatal cortices using methylated RNA immunoprecipitation (MeRIP) sequencing. We identified unique m⁶A binding motifs in stage-specific RNAs and found that more RNA transcripts are temporally methylated in embryonic cortices than in postnatal ones. Moreover, we found that cortical transcription factors and genes associated with neurological disorders are broadly as well specifically methylated at m⁶A sites. Our study highlights the importance of epitranscriptomic regulation in the developing cortex and provides a fundamental reference for future mechanistic examinations of m⁶A methylation-mediated gene expression regulation in normal brain development and neurological disorders.