Reciprocal regulation of m⁶A and noncoding RNAs across kingdoms

N⁶-methyladenosine (m⁶A) extends beyond mRNAs to modify diverse noncoding RNAs (ncRNAs), including long ncRNAs, circular RNAs, and miRNAs. Through stage-specific regulation, m⁶A orchestrates ncRNA biogenesis by modulating processing, stability, localization, and translation. At higher regulatory levels, m⁶A fine-tunes ncRNA functions across molecular and structural hierarchies by reshaping RNA-RNA and RNA-protein interactions that influence gene expression. Conversely, ncRNAs impose multilayered feedback on m⁶A writers, erasers, and readers, forming reciprocal loops that couple chromatin regulation with RNA metabolism. These hierarchical circuits constitute an epitranscriptomic layer that coordinates transcriptional and posttranscriptional control. We further outline conserved yet lineage-specific m⁶A-ncRNA networks across animals and plants, illustrating how this dynamic system integrates chemical marks with gene regulatory complexity across kingdoms.