RNA Modification N 6 Methyladenosine in Post transcriptional Regulation
N 6 methyladenosine (m6A) is the most prevalent internal messenger RNA (mRNA) chemical modification in eukaryotes. This methylation has been shown to be reversible in mammals. It is installed by a methyltransferase complex (writers) of METTL3, METTL14, and Wilms' tumor 1 associating protein (WTAP) and can be removed by demethylases (erasers) FTO and ALKBH5, which are iron(II) and a ketoglutarate dependent dioxygenases. The reversible and dynamic methylation exhibits significant functional roles in various biological processes. The m6A modification as an RNA mark is recognized by reader proteins, such as YTH domain family proteins. YTHDF2 regulates the stability of the methylated transcripts in cytoplasm; YTHDF1 promotes protein synthesis of the methylated mRNA by interacting with translation machinery. m6A as a switch controls the RNA structure to affect RNA protein interactions for biological regulation. Meanwhile, many m6A detection techniques were developed and applied in biology and medicine. The total m6A level in mRNA can be determined by ultra performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC QQQ MS/MS) two dimensional thin layer chromatography (2 D TLC) and dot blot. The m6A antibody affinity sequencing (MeRIP seq) was developed to map the m6A site location in a transcriptome wide manner. The single base resolution methods for single gene or whole transcripts were also invented.