Fig. 2
From: m6A-modified circRNAs: detections, mechanisms, and prospects in cancers
The dynamic and reversible process of m6A modification. The m6A modification can be installed by the multicomponent m6A methyltransferases complex (writers) which includes METTL3, METTL14, WTAP, VIRMA, RBM15/15B, ZC3H13 and CBLL1, as well as independent RNA methyltransferases such as METTL16, METTL5, ZCCHC4, and removed by demethylases (erasers) FTO and ALKBH5. Various binding proteins (readers) can then recognize the m6A modification to perform specific biological functions. In the nucleus, m6A can be identified by YTHDC1, HNRNPC/G, HNRNPA2B1, YTHDF2 and FMRP, and is involved in RNA alternative splicing, nuclear RNA processing, R-loop degradation, and RNA export. In the cytoplasm, m6A can be identified by YTHDF1/2/3, YTHDC2, IGF2BPs, eIF3, FMRP and PRRC2A, and regulates RNA stability, translation, and degradation