InterPro domain: IPR042296

Trm1 ( 2.1.1.216 ) dimethylates a single guanine residue at position 26 of a number of tRNAs using S-adenosyl-L-methionine as donor of the methyl groups [ 1 , 2 ]. In Saccharomyces cerevisiae, Trm1 is required for the modification of both mitochondrial and cytoplasmic tRNAs [ 3 ].

This superfamily represents the C terminus of Trm1. This domain is characterised by the presence zinc-cysteine cluster where a zinc atom is bound to four cysteine residues and functions as a structural element that holds the tRNA-binding site between the N- and C-terminal domains [ 4 ].

1. The tRNA(guanine-26,N2-N2) methyltransferase (Trm1) from the hyperthermophilic archaeon Pyrococcus furiosus: cloning, sequencing of the gene and its expression in Escherichia coli. Nucleic Acids Res. 26, 3753-61
2. Characterisation and enzymatic properties of tRNA(guanine 26, N (2), N (2))-dimethyltransferase (Trm1p) from Pyrococcus furiosus. J. Mol. Biol. 291, 375-92
3. Isolation and characterization of the TRM1 locus, a gene essential for the N2,N2-dimethylguanosine modification of both mitochondrial and cytoplasmic tRNA in Saccharomyces cerevisiae. J. Biol. Chem. 261, 9703-9
4. Crystal structure of tRNA N2,N2-guanosine dimethyltransferase Trm1 from Pyrococcus horikoshii. J. Mol. Biol. 383, 871-84