Queuosine formation in eukaryotic tRNA occurs via a mitochondrial localized heteromeric transglycoslase.
Item Type:Journal Article
Citation:Boland C., Hayes P.A., Santa-Maria I., Nishimura S. and Kelly V.P. 'Queuosine formation in eukaryotic tRNA occurs via a mitochondrial localized heteromeric transglycoslase' in Journal of Biological Chemistry, 284, (27), 2009, pp 18218-18227
Queuosine formation in eukaryotic tRNA occurs via a mitochondria-localized.pdf (published (author copy) peer-reviewed) 2.106Mb
tRNA guanine transglycosylase (TGT) enzymes are responsible for the formation of queuosine in the anticodon loop (position 34) of tRNAAsp, tRNAAsn, tRNAHis, and tRNATyr; an almost universal event in eubacterial and eukaryotic species. Despite extensive characterization of the eubacterial TGT the eukaryotic activity has remained undefined. Our search of mouse EST and cDNA data bases identified a homologue of the Escherichia coli TGT and three spliced variants of the queuine tRNA guanine transglycosylase domain containing 1 (QTRTD1) gene. QTRTD1 variant_1 (Qv1) was found to be the predominant adult form. Functional cooperativity of TGT and Qv1 was suggested by their coordinate mRNA expression in Northern blots and from their association in vivo by immunoprecipitation. Neither TGT nor Qv1 alone could complement a tgt mutation in E. coli. However, transglycosylase activity could be obtained when the proteins were combined in vitro. Confocal and immunoblot analysis suggest that TGT weakly interacts with the outer mitochondrial membrane possibly through association with Qv1, which was found to be stably associated with the organelle.
Science Foundation Ireland
Author: KELLY, VINCENT PATRICK
Publisher:The American Society for Biochemistry and Molecular Biology
Type of material:Journal Article
Series/Report no:Journal of Biological Chemistry
Availability:Full text available