Box C/D RNA guides for the ribose methylation of archaeal tRNAs. The tRNATrp intron guides the formation of two ribose-methylated nucleosides in the mature tRNATrp
Following a search of the Pyrococcus genomes for homologs of eukaryotic methylation guide small nucleolar RNAs, we have experimentally identified in Pyrococcus abyssi four novel box C/D small RNAs predicted to direct 2'-O-ribose methylations onto the first position of the anticodon in tRNALeu(C...
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Published in | Nucleic acids research Vol. 29; no. 22; pp. 4518 - 4529 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
England
Oxford Publishing Limited (England)
15.11.2001
Oxford University Press |
Subjects | |
Online Access | Get full text |
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Summary: | Following a search of the Pyrococcus genomes for homologs of eukaryotic methylation guide small nucleolar RNAs, we have experimentally identified in Pyrococcus abyssi four novel box C/D small RNAs predicted to direct 2'-O-ribose methylations onto the first position of the anticodon in tRNALeu(CAA), tRNALeu(UAA), elongator tRNAMet and tRNATrp, respectively. Remarkably, one of them corresponds to the intron of its presumptive target, pre-tRNATrp. This intron is predicted to direct in cis two distinct ribose methylations within the unspliced tRNA precursor, not only onto the first position of the anticodon in the 5' exon but also onto position 39 (universal tRNA numbering) in the 3' exon. The two intramolecular RNA duplexes expected to direct methylation, which both span an exon-intron junction in pre-tRNATrp, are phylogenetically conserved in euryarchaeotes. We have experimentally confirmed the predicted guide function of the box C/D intron in halophile Haloferax volcanii by mutagenesis analysis, using an in vitro splicing/RNA modification assay in which the two cognate ribose methylations of pre-tRNATrp are faithfully reproduced. Euryarchaeal pre-tRNATrp should provide a unique system to further investigate the molecular mechanisms of RNA-guided ribose methylation and gain new insights into the origin and evolution of the complex family of archaeal and eukaryotic box C/D small RNAs. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 To whom correspondence should be addressed. Tel: +33 5 61 33 59 34; Fax: +33 5 61 33 58 86; Email: bachel@ibcg.biotoul.fr |
ISSN: | 1362-4962 0305-1048 1362-4962 |
DOI: | 10.1093/nar/29.22.4518 |