title: Crystal structure of the tRNA 3' processing endoribonuclease tRNase Z from Thermotoga maritima.
abstract: The maturation of the tRNA 3' end is catalyzed by a tRNA 3' processing endoribonuclease named tRNase Z (RNase Z or 3'-tRNase) in eukaryotes, Archaea, and some bacteria. The tRNase Z generally cuts the 3' extra sequence from the precursor tRNA after the discriminator nucleotide. In contrast, Thermotoga maritima tRNase Z cleaves the precursor tRNA precisely after the CCA sequence. In this study, we determined the crystal structure of T. maritima tRNase Z at 2.6-A resolution. The tRNase Z has a four-layer alphabeta/betaalpha sandwich fold, which is classified as a metallo-beta-lactamase fold, and forms a dimer. The active site is located at one edge of the beta-sandwich and is composed of conserved motifs. Based on the structure, we constructed a docking model with the tRNAs that suggests how tRNase Z may recognize the substrate tRNAs.
authors.affiliation: Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Ishii
authors.forename: Asako
authors.initials: A
authors.lastname: Minagawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Takaku
authors.forename: Masamichi
authors.initials: M
authors.lastname: Takagi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nashimoto
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Yokoyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004722:Endoribonucleases / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D012323:RNA Processing, Post-Transcriptional; D012343:RNA, Transfer / Q000737:chemistry* / Q000378:metabolism; D016415:Sequence Alignment; D020124:Thermotoga maritima / Q000201:enzymology* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D012343:RNA, Transfer; D004722:Endoribonucleases; C110250:RNase Z; C045782:3'-pre-tRNase