title: Discovery of a gene family critical to wyosine base formation in a subset of phenylalanine-specific transfer RNAs.
abstract: A large number of post-transcriptional base modifications in transfer RNAs have been described (Sprinzl, M., Horn, C., Brown, M., Ioudovitch, A., and Steinberg, S. (1998) Nucleic Acids Res. 26, 148-153). These modifications enhance and expand tRNA function to increase cell viability. The intermediates and genes essential for base modifications in many instances remain unclear. An example is wyebutosine (yW), a fluorescent tricyclic modification of an invariant guanosine situated on the 3'-side of the tRNA(Phe) anticodon. Although biosynthesis of yW involves several reaction steps, only a single pathway-specific enzyme has been identified (Kalhor, H. R., Penjwini, M., and Clarke, S. (2005) Biochem. Biophys. Res. Commun. 334, 433-440). We used comparative genomics analysis to identify a cluster of orthologous groups (COG0731) of wyosine family biosynthetic proteins. Gene knock-out and complementation studies in Saccharomyces cerevisiae established a role for YPL207w, a COG0731 ortholog that encodes an 810-amino acid polypeptide. Further analysis showed the accumulation of N(1)-methylguanosine (m(1)G(37)) in tRNA from cells bearing a YPL207w deletion. A similar lack of wyosine base and build-up of m(1)G(37) is seen in certain mammalian tumor cell lines. We proposed that the 810-amino acid COG0731 polypeptide participates in converting tRNA(Phe)-m(1)G(37) to tRNA(Phe)-yW.
authors.affiliation: Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: William F
authors.initials: WF
authors.lastname: Waas
authors.forename: Valérie
authors.initials: V
authors.lastname: de Crécy-Lagard
authors.forename: Paul
authors.initials: P
authors.lastname: Schimmel
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005816:Genetic Complementation Test; D006151:Guanosine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry; D006575:Heterocyclic Compounds, 3-Ring / Q000737:chemistry; D006868:Hydrolysis; D015394:Molecular Structure; D005810:Multigene Family; D010802:Phylogeny; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*
chemical_list: D006575:Heterocyclic Compounds, 3-Ring; D012346:RNA, Transfer, Amino Acyl; C506909:wyebutosine; D006151:Guanosine; C012100:wyosine