Fig. 6: Structural comparison of MT-A70-like family members.
From: Mechanism for the substrate recognition by a eukaryotic DNA N6-adenine methyltransferase complex
a Illustration of the domain organization of Tetrahymena thermophila (Tt) MTA1, MTA9 and MTA9-B, Homo sapiens (Hs) METTL3 and METTL14, and Arabidopsis thaliana (At) METTL4. The MTase domains are aligned at their C-termini. Abbreviations: CTE C-terminal extension; MID middle domain. b–d Structural comparison between MTA1cMTA9 (b), METTL3–METTL14 complex (PDB ID: 5IL1) (c) and METTL4 (PDB ID: 7CV7) (d) in two different views. The ligand SAM is shown in sticks. e Model for MTA1c-mediated DNA methylation. DNA substrate is initially captured by p1, which is connected to MTA1 through p2. p1 together with MTA1 and MTA9 (or MTA9-B) clamps DNA near the catalytic center on MTA1. Then MTA1, assisted by p2, transfers the methyl group from SAM to the DNA substrate. The cartoon model was drawn in Adobe Illustrator.
