The tRNA N2,N2,-dimethylguanosine-26 methyltransferase encoded by gene trm1 increases efficiency of suppression of an ochre codon in Schizosaccharomyces pombe
C. Niederberger et al., The tRNA N2,N2,-dimethylguanosine-26 methyltransferase encoded by gene trm1 increases efficiency of suppression of an ochre codon in Schizosaccharomyces pombe, FEBS LETTER, 464(1-2), 1999, pp. 67-70
In the majority of eukaryotic tRNAs, the guanosine at position 26 is modifi
ed by a dimethyl group, but so far a function of this modification has not
been detected. We isolated the Schizosaccharomyces pombe gene, trm1, encodi
ng the tRNA N2,N2-dimethylguanosine-26 methyltransferase. Strains having th
e gene deleted completely lack N2,N2-dimethylguanosine. In strains carrying
the weak ochre tRNA suppressor sup3-i, deletion of trm1 abolishes suppress
ion indicating that the tr ml deletion acts as an antisuppressor mutation.
The result suggests that in vivo N2,N2-dimethylguanosine-26 increases the c
apacity of the sup3-i serine tRNA to translate the UAA (ochre) codon. (C) 1
999 Federation of European Biochemical Societies.