title: Interactions of release factor RF3 with the translation machinery.
abstract: The bacterial release factor RF3 is a GTPase that has been implicated in multiple, incompletely understood steps of protein synthesis. This study explores the genetic interaction of RF3 with other components of the translation machinery. RF3 contributes to translation termination by recycling the class I release factors RF1 and RF2 off post-termination ribosomes. RF3 has also been implicated in dissociation of peptidyl-tRNAs from elongating ribosomes and in a post-peptidyltransferase quality control (post-PT QC) mechanism that selectively terminates ribosomes carrying erroneous peptides. A majority of the in vivo studies on RF3 have been carried out in K-12 strains of Escherichia coli which carry a partially defective RF2 protein with an Ala to Thr substitution at position 246. Here, the contribution of the K-12 specific RF2 variant to RF3 activities has been investigated. Strain reconstruction experiments in both E. coli and Salmonella enterica demonstrate that defects in termination and post-PT QC that are associated with RF3 loss, as well as phenotypes uncovered by phenotypic profiling, are all substantially ameliorated when the incompletely active K-12-specific RF2 protein is replaced by a fully active Ala246 RF2. These results indicate that RF3 loss is well tolerated in bacteria with fully active class I release factors, but that many of the previously reported phenotypes for RF3 deletion strains have been compromised by the presence of a partially defective RF2.
authors: School of Biological Sciences, University of Missouri-Kansas City, 5007 Rockhill Rd., Kansas City, MO, 64110, USA, oconnormi@umkc.edu.
authors: Michael
authors: M
authors: O'Connor
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002441:Cefsulodin / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D050296:Microbial Viability / Q000187:drug effects / Q000235:genetics; D009154:Mutation; D010443:Peptide Chain Termination, Translational; D010454:Peptide Termination Factors / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D011485:Protein Binding; D014176:Protein Biosynthesis; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism; D019779:Salmonella enterica / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D010454:Peptide Termination Factors; D012346:RNA, Transfer, Amino Acyl; C489005:prfA protein, E coli; C489006:prfB protein, E coli; C489007:prfC protein, E coli; C019037:tRNA, peptidyl-; D002441:Cefsulodin
references: Cold Spring Harb Symp Quant Biol. 1969;34:479-88
references: 4909515
references: Mol Microbiol. 1999 Jan;31(1):53-8
references: 9987109
references: J Bacteriol. 2007 Apr;189(8):3147-55
references: 17293419
references: Cell. 2011 Jan 7;144(1):143-56
references: 21185072
references: BMC Genomics. 2007 Jan 10;8:15
references: 17214893
references: Trends Biochem Sci. 2000 Nov;25(11):561-6
references: 11084369
references: J Biol Chem. 1956 Jan;218(1):97-106
references: 13278318
references: J Biol Chem. 2007 Dec 7;282(49):35638-45
references: 17932046
references: Biochimie. 2000 Aug;82(8):683-91
references: 11018284
references: J Mol Biol. 1999 Aug 27;291(4):745-59
references: 10452886
references: Biochimie. 1986 May;68(5):705-13
references: 3089329
references: Biochimie. 2011 May;93(5):834-44
references: 21281690
references: J Mol Biol. 2011 Jul 1;410(1):1-9
references: 21575643
references: Mol Syst Biol. 2006;2:2006.0008
references: 16738554
references: J Biol Chem. 2014 Jun 20;289(25):17589-96
references: 24798339
references: Cold Spring Harb Symp Quant Biol. 1969;34:469-77
references: 4909514
references: J Mol Biol. 1971 May 14;57(3):423-35
references: 4931677
references: Proc Natl Acad Sci U S A. 1994 Jun 21;91(13):5848-52
references: 8016077
references: J Bacteriol. 2011 Jan;193(1):154-62
references: 21037010
references: Nucleic Acids Res. 1997 Mar 15;25(6):1185-93
references: 9092628
references: J Biol Chem. 1995 May 5;270(18):10595-600
references: 7737996
references: Proc Natl Acad Sci U S A. 1994 Jun 21;91(13):5798-802
references: 8016068
references: Nature. 2009 Jan 8;457(7226):161-6
references: 19092806
references: Proc Natl Acad Sci U S A. 2000 Jun 6;97(12):6640-5
references: 10829079
references: Cell. 2011 Oct 14;147(2):396-408
references: 22000017
references: Mol Microbiol. 2011 Jan;79(2):331-41
references: 21219455
references: EMBO J. 1997 Jul 1;16(13):4126-33
references: 9233821
references: EMBO J. 2000 Dec 15;19(24):6900-7
references: 11118225