title: Assigning a function to a conserved group of proteins: the tRNA 3'-processing enzymes.
abstract: Accurate tRNA 3' end maturation is essential for aminoacylation and thus for protein synthesis in all organisms. Here we report the first identification of protein and DNA sequences for tRNA 3'-processing endonucleases (RNase Z). Purification of RNase Z from wheat identified a 43 kDa protein correlated with the activity. Peptide sequences obtained from the purified protein were used to identify the corresponding gene. In vitro expression of the homologous proteins from Arabidopsis thaliana and Methano coccus janaschii confirmed their tRNA 3'-processing activities. These RNase Z proteins belong to the ELAC1/2 family of proteins and to the cluster of orthologous proteins COG 1234. The RNase Z enzymes from A.thaliana and M.janaschii are the first members of these families to which a function can now be assigned. Proteins with high sequence similarity to the RNase Z enzymes from A.thaliana and M.janaschii are present in all three kingdoms.
authors.affiliation: Molekulare Botanik, Universität Ulm, D-89069 Ulm, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Schiffer
authors.forename: Sylvia
authors.initials: S
authors.lastname: Rösch
authors.forename: Anita
authors.initials: A
authors.lastname: Marchfelder
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology; D001105:Archaea / Q000201:enzymology; D001419:Bacteria / Q000201:enzymology; D002467:Cell Nucleus / Q000201:enzymology; D002736:Chloroplasts / Q000201:enzymology; D002850:Chromatography, Gel; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000378:metabolism; D019992:Databases as Topic; D004720:Endonucleases / Q000378:metabolism; D004722:Endoribonucleases / Q000737:chemistry; D020224:Expressed Sequence Tags; D006801:Humans; D017017:Methanococcus / Q000201:enzymology; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D017434:Protein Structure, Tertiary; D012343:RNA, Transfer / Q000737:chemistry / Q000378:metabolism*; D014908:Triticum / Q000201:enzymology
chemical_list: D018076:DNA, Complementary; D012343:RNA, Transfer; D004720:Endonucleases; D004722:Endoribonucleases; C110250:RNase Z