title: Crystal structure analysis of the translation factor RF3 (release factor 3).
abstract: The bacterial translational GTPases release factor RF3 promotes translation termination by recycling RF1 or RF2. Here, we present the crystal structures of RF3 complexed with GDP and guanosine 3',5'-(bis)diphosphate (ppGpp) at resolutions of 1.8 and 3.0Å, respectively. ppGpp is involved in the so-called "stringent response" of bacteria. ppGpp binds at the same site as GDP, suggesting that GDP and ppGpp are two alternative physiologically relevant ligands of RF3. We also found that ppGpp decelerates the recycling of RF1 by RF3. These lines of evidence suggest that RF3 functions both as a cellular metabolic sensor and as a regulator.
authors.affiliation: Graduate School of Life Science, University of Hyogo, Ako 678-1297, Japan.
authors.forename: Kiyohito
authors.initials: K
authors.lastname: Kihira
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Shomura
authors.forename: Naoki
authors.initials: N
authors.lastname: Shibata
authors.forename: Masaya
authors.initials: M
authors.lastname: Kitamura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nakagawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Ueda
authors.forename: Kozo
authors.initials: K
authors.lastname: Ochi
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Higuchi
mesh_terms: D018360:Crystallography, X-Ray; D016969:Desulfovibrio vulgaris; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism*; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D008958:Models, Molecular; D010454:Peptide Termination Factors / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation
chemical_list: D029968:Escherichia coli Proteins; D010454:Peptide Termination Factors; C489005:prfA protein, E coli; C489007:prfC protein, E coli; D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate