Structure and mechanism of the methyltransferase ribozyme MTR1.

ABSTRACT: RNA-catalyzed RNA methylation was recently shown to be part of the catalytic repertoire of ribozymes. The methyltransferase ribozyme MTR1 catalyzes the site-specific synthesis of 1-methyladenosine (m¹A) in RNA, using O⁶-methylguanine (m⁶G) as a methyl group donor. Here, we report the crystal structure of MTR1 at a resolution of 2.8 Å, which reveals a guanine-binding site reminiscent of natural guanine riboswitches. The structure represents the postcatalytic state of a split ribozyme in complex with the m¹A-containing RNA product and the demethylated cofactor guanine. The structural data suggest the mechanistic involvement of a protonated cytidine in the methyl transfer reaction. A synergistic effect of two 2'-O-methylated ribose residues in the a

SUBMITTER: Scheitl CPM 

PROVIDER: S-EPMC7612680 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature