In:
RNA, Cold Spring Harbor Laboratory, Vol. 9, No. 5 ( 2003-05), p. 574-585
Abstract:
Methylation of tRNA at the N-1 position of guanosine to form m 1 G occurs widely in nature. It occurs at position 37 in tRNAs from all three kingdoms, and the methyltransferase that catalyzes this reaction is known from previous work of others to be critically important for cell growth in Escherichia coli and the yeast Saccharomyces cerevisiae . m 1 G is also widely found at position 9 in eukaryotic tRNAs, but the corresponding methyltransferase was unknown. We have used a biochemical genomics approach with a collection of purified yeast GST-ORF fusion proteins to show that m 1 G 9 formation of yeast tRNA Gly is associated with ORF YOL093w, named TRM10 . Extracts lacking Trm10p have undetectable levels of m 1 G 9 methyltransferase activity but retain normal m 1 G 37 methyltransferase activity. Yeast Trm10p purified from E. coli quantitatively modifies the G 9 position of tRNA Gly in an S -adenosylmethionine-dependent fashion. Trm10p is responsible in vivo for most if not all m 1 G 9 modification of tRNAs, based on two results: tRNA Gly purified from a trm10- Δ/ trm10- Δ strain is lacking detectable m 1 G; and a primer extension block occurring at m 1 G 9 is removed in trm10- Δ/ trm10- Δ-derived tRNAs for all 9 m 1 G 9 -containing species that were testable by this method. There is no obvious growth defect of trm10- Δ/ trm10- Δ strains. Trm10p bears no detectable resemblance to the yeast m 1 G 37 methyltransferase, Trm5p, or its orthologs. Trm10p homologs are found widely in eukaryotes and many archaea, with multiple homologs in several metazoans, including at least three in humans.
Type of Medium:
Online Resource
ISSN:
1355-8382
,
1469-9001
Language:
English
Publisher:
Cold Spring Harbor Laboratory
Publication Date:
2003
detail.hit.zdb_id:
1475737-0
SSG:
12
