N4methyladenosine

N4methyladenosine, often abbreviated as m4A, is a modified form of adenosine, one of the four nucleobases found in RNA. This modification involves the addition of a methyl group to the nitrogen atom at the fourth position of the adenine base. m4A is a widespread epitranscriptomic modification, meaning it occurs on RNA molecules after they have been transcribed from DNA. It is found in various RNA species, including messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), across a wide range of organisms from bacteria to eukaryotes.

The presence and regulation of m4A modifications are thought to play significant roles in cellular processes. Research suggests that m4A can influence RNA stability, splicing, translation efficiency, and localization. While the precise mechanisms by which m4A exerts its effects are still under investigation, specific proteins known as "writer," "eraser," and "reader" enzymes are believed to mediate its installation, removal, and interpretation, respectively. The dynamic nature of m4A modification highlights its potential involvement in cellular responses to environmental changes and in the fine-tuning of gene expression. Aberrant m4A patterns have been implicated in various diseases, including cancer, underscoring the importance of this modification in cellular homeostasis.