title: Cryo-EM visualization of the ribosome in termination complex with apo-RF3 and RF1.
abstract: Termination of messenger RNA translation in Bacteria and Archaea is initiated by release factors (RFs) 1 or 2 recognizing a stop codon in the ribosomal A site and releasing the peptide from the P-site transfer RNA. After release, RF-dissociation is facilitated by the G-protein RF3. Structures of ribosomal complexes with RF1 or RF2 alone or with RF3 alone-RF3 bound to a non-hydrolyzable GTP-analog-have been reported. Here, we present the cryo-EM structure of a post-termination ribosome containing both apo-RF3 and RF1. The conformation of RF3 is distinct from those of free RF3•GDP and ribosome-bound RF3•GDP(C/N)P. Furthermore, the conformation of RF1 differs from those observed in RF3-lacking ribosomal complexes. Our study provides structural keys to the mechanism of guanine nucleotide exchange on RF3 and to an L12-mediated ribosomal recruitment of RF3. In conjunction with previous observations, our data provide the foundation to structurally characterize the complete action cycle of the G-protein RF3. DOI:http://dx.doi.org/10.7554/eLife.00411.001.
authors.affiliation: Department of Biochemistry and Molecular Biophysics , Howard Hughes Medical Institute, Columbia University , New York City , United States.
authors.forename: Jesper
authors.initials: J
authors.lastname: Pallesen
authors.forename: Yaser
authors.initials: Y
authors.lastname: Hashem
authors.forename: Gürkan
authors.initials: G
authors.lastname: Korkmaz
authors.forename: Ravi Kiran
authors.initials: RK
authors.lastname: Koripella
authors.forename: Chenhui
authors.initials: C
authors.lastname: Huang
authors.forename: Måns
authors.initials: M
authors.lastname: Ehrenberg
authors.forename: Suparna
authors.initials: S
authors.lastname: Sanyal
authors.forename: Joachim
authors.initials: J
authors.lastname: Frank
mesh_terms: D001665:Binding Sites; D020285:Cryoelectron Microscopy; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D056004:Molecular Dynamics Simulation; D009154:Mutation; D010454:Peptide Termination Factors / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D011485:Protein Binding; D011487:Protein Conformation; D012329:RNA, Bacterial / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis*; D012269:Ribosomal Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism* / Q000648:ultrastructure; D013997:Time Factors; D061806:Transcription Termination, Genetic
chemical_list: D029968:Escherichia coli Proteins; D010454:Peptide Termination Factors; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012269:Ribosomal Proteins; C489005:prfA protein, E coli; C489007:prfC protein, E coli; C512844:rplL protein, E coli; D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate
keywords: Cryo-EM; E. coli; L7/L12; RF1; RF3; Ribosome; Structure