N6metüüladenosiin

N6-methyladenosine, often abbreviated as m6A, is the most abundant and prevalent internal modification of eukaryotic messenger RNA (mRNA). It is also found on other RNA species, including ribosomal RNA, transfer RNA, and long non-coding RNA. This modification involves the methylation of the nitrogen atom at the sixth position of adenine. The m6A modification is dynamic, meaning it can be added (methylated) and removed (demethylated), suggesting a regulatory role in gene expression.

The m6A modification plays a critical role in a variety of cellular processes. These include mRNA splicing, nuclear export, translation efficiency, and RNA stability. The "writer" enzymes responsible for m6A deposition are primarily members of the methyltransferase-like (METTL) family, with METTL3 and METTL14 being key components of the core m6A methyltransferase complex. Conversely, "eraser" enzymes, such as the Fat mass and obesity-associated (FTO) protein and the AlkB homolog 5 (ALKBH5), are responsible for demethylating m6A.

"Reader" proteins, such as YTH domain-containing proteins, recognize and bind to m6A-modified RNA, thereby mediating the downstream effects of the modification. These reader proteins can influence mRNA fate, including its degradation or translation. Due to its widespread involvement in fundamental biological processes, dysregulation of m6A modification has been implicated in numerous diseases, including cancer, neurological disorders, and metabolic diseases, making it a significant area of research in molecular biology and medicine.