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'Stop' in protein synthesis is modulated with exquisite subtlety by an extended RNA translation signal. Biochem Soc Trans 2018; 46:1615-1625. [PMID: 30420414 DOI: 10.1042/bst20180190] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 09/30/2018] [Accepted: 10/04/2018] [Indexed: 02/08/2023]
Abstract
Translational stop codons, UAA, UAG, and UGA, form an integral part of the universal genetic code. They are of significant interest today for their underlying fundamental role in terminating protein synthesis, but also for their potential utilisation for programmed alternative translation events. In diverse organisms, UAA has wide usage, but it is puzzling that the high fidelity UAG is selected against and yet UGA, vulnerable to suppression, is widely used, particularly in those archaeal and bacterial genomes with a high GC content. In canonical protein synthesis, stop codons are interpreted by protein release factors that structurally and functionally mimic decoding tRNAs and occupy the decoding site on the ribosome. The release factors make close contact with the decoding complex through multiple interactions. Correct interactions cause conformational changes resulting in new and enhanced contacts with the ribosome, particularly between specific bases in the mRNA and rRNA. The base following the stop codon (fourth or +4 base) may strongly influence decoding efficiency, facilitating alternative non-canonical events like frameshifting or selenocysteine incorporation. The fourth base is drawn into the decoding site with a compacted stop codon in the eukaryotic termination complex. Surprisingly, mRNA sequences upstream and downstream of this core tetranucleotide signal have a significant influence on the strength of the signal. Since nine bases downstream of the stop codon are within the mRNA channel, their interactions with rRNA, and r-proteins may affect efficiency. With this understanding, it is now possible to design stop signals of desired strength for specific applied purposes.
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Baggett NE, Zhang Y, Gross CA. Global analysis of translation termination in E. coli. PLoS Genet 2017; 13:e1006676. [PMID: 28301469 PMCID: PMC5373646 DOI: 10.1371/journal.pgen.1006676] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 03/30/2017] [Accepted: 03/08/2017] [Indexed: 01/01/2023] Open
Abstract
Terminating protein translation accurately and efficiently is critical for both protein fidelity and ribosome recycling for continued translation. The three bacterial release factors (RFs) play key roles: RF1 and 2 recognize stop codons and terminate translation; and RF3 promotes disassociation of bound release factors. Probing release factors mutations with reporter constructs containing programmed frameshifting sequences or premature stop codons had revealed a propensity for readthrough or frameshifting at these specific sites, but their effects on translation genome-wide have not been examined. We performed ribosome profiling on a set of isogenic strains with well-characterized release factor mutations to determine how they alter translation globally. Consistent with their known defects, strains with increasingly severe release factor defects exhibit increasingly severe accumulation of ribosomes over stop codons, indicative of an increased duration of the termination/release phase of translation. Release factor mutant strains also exhibit increased occupancy in the region following the stop codon at a significant number of genes. Our global analysis revealed that, as expected, translation termination is generally efficient and accurate, but that at a significant number of genes (≥ 50) the ribosome signature after the stop codon is suggestive of translation past the stop codon. Even native E. coli K-12 exhibits the ribosome signature suggestive of protein extension, especially at UGA codons, which rely exclusively on the reduced function RF2 variant of the K-12 strain for termination. Deletion of RF3 increases the severity of the defect. We unambiguously demonstrate readthrough and frameshifting protein extensions and their further accumulation in mutant strains for a few select cases. In addition to enhancing recoding, ribosome accumulation over stop codons disrupts attenuation control of biosynthetic operons, and may alter expression of some overlapping genes. Together, these functional alterations may either augment the protein repertoire or produce deleterious proteins. Proteins are the cellular workhorses, performing essentially all of the functions required for cell and organismal survival. But, it takes a great deal of energy to make proteins, making it critical that proteins are made accurately and in the proper time frame. After a ribosome synthesizes a protein, release factors catalyze the accurate and timely release of the finished protein from the ribosome, a process called termination. Ribosomes are then recycled and start the next protein. We utilized ribosome profiling, a method that allows us to follow the position of every ribosome that is making a protein, to globally investigate and strengthen insights on termination fidelity for cells with and without mutant release factors. We find that as we decrease release factor function, the time to terminate/release a protein increases across the genome. We observe that the accuracy of terminating a protein at the correct place decreases on a global scale. Using this metric we identify genes with inherently low termination efficiency and confirm two novel events resulting in extended protein products. In addition we find that beyond disrupting accurate protein synthesis, release factor mutations can alter expression of genes involved in the production of key amino acids.
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Affiliation(s)
- Natalie E. Baggett
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
| | - Yan Zhang
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
| | - Carol A. Gross
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, California, United States of America
- California Institute of Quantitative Biology, University of California, San Francisco, San Francisco, California, United States of America
- * E-mail:
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Dujeancourt L, Richter R, Chrzanowska-Lightowlers ZM, Bonnefoy N, Herbert CJ. Interactions between peptidyl tRNA hydrolase homologs and the ribosomal release factor Mrf1 in S. pombe mitochondria. Mitochondrion 2013; 13:871-80. [PMID: 23892058 PMCID: PMC3919214 DOI: 10.1016/j.mito.2013.07.115] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 06/19/2013] [Accepted: 07/18/2013] [Indexed: 11/22/2022]
Abstract
Mitochondrial translation synthesizes key subunits of the respiratory complexes. In Schizosaccharomyces pombe, strains lacking Mrf1, the mitochondrial stop codon recognition factor, are viable, suggesting that other factors can play a role in translation termination. S. pombe contains four predicted peptidyl tRNA hydrolases, two of which (Pth3 and Pth4), have a GGQ motif that is conserved in class I release factors. We show that high dosage of Pth4 can compensate for the absence of Mrf1 and loss of Pth4 exacerbates the lack of Mrf1. Also Pth4 is a component of the mitochondrial ribosome, suggesting that it could help recycling stalled ribosomes. In S. pombe the peptidyl tRNA hydrolases Pth3 and Pth4 are mitochondrial proteins. Pth3 and Pth4 are associated with the mitochondrial ribosome and the large subunit. Deletion of pth4 and mrf1, encoding the mitochondrial release factor, is co-lethal. Over-expression of pth4 compensates for the deletion of mrf1. Pth4 can act as a release factor in S. pombe mitochondria.
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Affiliation(s)
- Laurent Dujeancourt
- Centre de Génétique Moléculaire, UPR3404, FRC3115, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
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Leung EKY, Suslov N, Tuttle N, Sengupta R, Piccirilli JA. The Mechanism of Peptidyl Transfer Catalysis by the Ribosome. Annu Rev Biochem 2011; 80:527-55. [DOI: 10.1146/annurev-biochem-082108-165150] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Nikolai Suslov
- Department of Biochemistry and Molecular Biology, Chicago, Illinois 60637
| | - Nicole Tuttle
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637;
| | - Raghuvir Sengupta
- Department of Biochemistry, Stanford University, Stanford, California 94305
| | - Joseph Anthony Piccirilli
- Department of Biochemistry and Molecular Biology, Chicago, Illinois 60637
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637;
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Nakamura Y, Ito K. tRNA mimicry in translation termination and beyond. WILEY INTERDISCIPLINARY REVIEWS-RNA 2011; 2:647-68. [DOI: 10.1002/wrna.81] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Youngman EM, McDonald ME, Green R. Peptide release on the ribosome: mechanism and implications for translational control. Annu Rev Microbiol 2008; 62:353-73. [PMID: 18544041 DOI: 10.1146/annurev.micro.61.080706.093323] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Peptide release, the reaction that hydrolyzes a completed protein from the peptidyl-tRNA upon completion of translation, is catalyzed in the active site of the large subunit of the ribosome and requires a class I release factor protein. The ribosome and release factor protein cooperate to accomplish two tasks: recognition of the stop codon and catalysis of peptidyl-tRNA hydrolysis. Although many fundamental questions remain, substantial progress has been made in the past several years. This review summarizes those advances and presents current models for the mechanisms of stop codon specificity and catalysis of peptide release. Finally, we discuss how these views fit into a larger emerging theme in the translation field: the importance of induced fit and conformational changes for progression through the translation cycle.
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Affiliation(s)
- Elaine M Youngman
- Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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Poole ES, Young DJ, Askarian-Amiri ME, Scarlett DJG, Tate WP. Accommodating the bacterial decoding release factor as an alien protein among the RNAs at the active site of the ribosome. Cell Res 2007; 17:591-607. [PMID: 17621307 DOI: 10.1038/cr.2007.56] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The decoding release factor (RF) triggers termination of protein synthesis by functionally mimicking a tRNA to span the decoding centre and the peptidyl transferase centre (PTC) of the ribosome. Structurally, it must fit into a site crafted for a tRNA and surrounded by five other RNAs, namely the adjacent peptidyl tRNA carrying the completed polypeptide, the mRNA and the three rRNAs. This is achieved by extending a structural domain from the body of the protein that results in a critical conformational change allowing it to contact the PTC. A structural model of the bacterial termination complex with the accommodated RF shows that it makes close contact with the first, second and third bases of the stop codon in the mRNA with two separate loops of structure: the anticodon loop and the loop at the tip of helix alpha5. The anticodon loop also makes contact with the base following the stop codon that is known to strongly influence termination efficiency. It confirms the close contact of domain 3 of the protein with the key RNA structures of the PTC. The mRNA signal for termination includes sequences upstream as well as downstream of the stop codon, and this may reflect structural restrictions for specific combinations of tRNA and RF to be bound onto the ribosome together. An unbiased SELEX approach has been investigated as a tool to identify potential rRNA-binding contacts of the bacterial RF in its different binding conformations within the active centre of the ribosome.
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Affiliation(s)
- Elizabeth S Poole
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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8
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Chapman B, Brown C. Translation termination in Arabidopsis thaliana: characterisation of three versions of release factor 1. Gene 2004; 341:219-25. [PMID: 15474304 DOI: 10.1016/j.gene.2004.06.053] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Revised: 05/14/2004] [Accepted: 06/29/2004] [Indexed: 10/26/2022]
Abstract
Translation termination is mediated in all eukaryotes by the two release factors eRF1 and eRF3. Most organisms have a single eRF1 gene, however, three isogenes of eRF1 are found in Arabidopsis thaliana. They have no introns in the coding region which may indicate that some are pseudogenes. However, each was expressed and able to rescue a temperature sensitive eRF1-mutant of Saccharomyces cerevisiae indicating functional redundancy in A. thaliana. While normally a highly accurate process, translation termination can be directed to fail by sequence elements within an messenger RNA (mRNA). Interestingly, a well-characterised readthrough element follows the stop codon in one of these three isogenes (designated eRF1-1). This element was shown to be capable of inducing readthrough in an in vitro assay using a dual luciferase reporter, but surprisingly readthrough could not be detected using the complete gene context. The results highlight the diversity and duplication of genes within plant genomes, but also emphasize the conservation of the translation process across kingdoms.
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Affiliation(s)
- Bernice Chapman
- Department of Biochemistry, University of Otago, PO Box 56, Dunedin, New Zealand
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Abstract
It was first suggested that the ribosome is associated with protein synthesis in the 1950s. Initially, its components were revealed as surface-accessible proteins and as molecules of RNA apparently providing a scaffold for subunit shape. Attributing function to the proteins proved difficult, although bacterial protein L11 proved essential for binding one of the decoding protein release factors (RFs). With the discovery that RNA could be a catalyst, interest focussed on the rRNA that, in partnership with mRNA and tRNAs, could potentially mediate the chemical reaction underlying protein synthesis. rRNA interactions and conformational changes were invoked as key elements that facilitated function. The decoding RFs, which are proteins, are exceptions to this rule because they usurp a tRNA function in mediating stop signal recognition. Cryoelectron microscopy and associated image reconstruction technology have now given dramatic snapshots of almost every step of protein synthesis, and X-ray crystallography has revealed, at last, the subunits and monomeric ribosome in exquisite atomic detail.
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Affiliation(s)
- Warren P Tate
- Department of Biochemistry, University of Otago, Dunedin, New Zealand.
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Chavatte L, Frolova L, Laugâa P, Kisselev L, Favre A. Stop codons and UGG promote efficient binding of the polypeptide release factor eRF1 to the ribosomal A site. J Mol Biol 2003; 331:745-58. [PMID: 12909007 DOI: 10.1016/s0022-2836(03)00813-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
To investigate the codon dependence of human eRF1 binding to the mRNA-ribosome complex, we examined the formation of photocrosslinks between ribosomal components and mRNAs bearing a photoactivable 4-thiouridine probe in the first position of the codon located in the A site. Addition of eRF1 to the phased mRNA-ribosome complexes triggers a codon-dependent quenching of crosslink formation. The concentration of eRF1 triggering half quenching ranges from low for the three stop codons, to intermediate for s4UGG and high for other near-cognate triplets. A theoretical analysis of the photochemical processes occurring in a two-state bimolecular model raises a number of stringent conditions, fulfilled by the system studied here, and shows that in any case sound KD values can be extracted if the ratio mT/KD<<1 (mT is total concentration of mRNA added). Considering the KD values obtained for the stop, s4UGG and sense codons (approximately 0.06 microM, 0.45 microM and 2.3 microM, respectively) and our previous finding that only the stop and s4UGG codons are able to promote formation of an eRF1-mRNA crosslink, implying a role for the NIKS loop at the tip of the N domain, we propose a two-step model for eRF1 binding to the A site: a codon-independent bimolecular step is followed by an isomerisation step observed solely with stop and s4UGG codons. Full recognition of the stop codons by the N domain of eRF1 triggers a rearrangement of bound eRF1 from an open to a closed conformation, allowing the universally conserved GGQ loop at the tip of the M domain to come into close proximity of the peptidyl transferase center of the ribosome. UGG is expected to behave as a cryptic stop codon, which, owing to imperfect eRF1-codon recognition, does not allow full reorientation of the M domain of eRF1. As far as the physical steps of eRF1 binding to the ribosome are considered, they appear to closely mimic the behaviour of the tRNA/EF-Tu/GTP complex, but clearly eRF1 is endowed with a greater conformational flexibility than tRNA.
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Affiliation(s)
- Laurent Chavatte
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7-Paris 6, 2 place Jussieu Tour 43, 75251 Paris, France
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11
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Bulygin KN, A Demeshkina N, Frolova LY, Graifer DM, Ven'yaminova AG, Kisselev LL, Karpova GG. The ribosomal A site-bound sense and stop codons are similarly positioned towards the A1823-A1824 dinucleotide of the 18S ribosomal RNA. FEBS Lett 2003; 548:97-102. [PMID: 12885414 DOI: 10.1016/s0014-5793(03)00755-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Positioning of the mRNA codon towards the 18S ribosomal RNA in the A site of human 80S ribosomes has been studied applying short mRNA analogs containing either the stop codon UAA or the sense codon UCA with a perfluoroaryl azide group at the uridine residue. Bound to the ribosomal A site, a modified codon crosslinks exclusively to the 40S subunits under mild UV irradiation. This result is inconsistent with the hypothesis [Ivanov et al. (2001) RNA 7, 1683-1692] which requires direct contact between the large rRNA and the stop codon of the mRNA as recognition step at translation termination. Both sense and stop codons crosslink to the same A1823/A1824 invariant dinucleotide in helix 44 of 18S rRNA. The data point to the resemblance between the ternary complexes formed at elongation (sense codon.aminoacyl-tRNA.AA dinucleotide of 18S rRNA) and termination (stop codon.eRF1.AA dinucleotide of 18S rRNA) steps of protein synthesis and support the view that eRF1 may be considered as a functional mimic of aminoacyl-tRNA.
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MESH Headings
- Azides
- Base Sequence
- Binding Sites
- Codon
- Codon, Terminator
- Cross-Linking Reagents
- Dinucleoside Phosphates
- Oligoribonucleotides/metabolism
- Protein Biosynthesis/genetics
- RNA, Bacterial/metabolism
- RNA, Messenger/metabolism
- RNA, Ribosomal, 18S/chemistry
- RNA, Ribosomal, 18S/metabolism
- RNA, Transfer, Amino Acyl
- RNA, Transfer, Phe
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Affiliation(s)
- Konstantin N Bulygin
- Novosibirsk Institute of Bioorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090 Russia
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12
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Scarlett DJG, McCaughan KK, Wilson DN, Tate WP. Mapping functionally important motifs SPF and GGQ of the decoding release factor RF2 to the Escherichia coli ribosome by hydroxyl radical footprinting. Implications for macromolecular mimicry and structural changes in RF2. J Biol Chem 2003; 278:15095-104. [PMID: 12458201 DOI: 10.1074/jbc.m211024200] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The function of the decoding release factor (RF) in translation termination is to couple cognate recognition of the stop codon in the mRNA with hydrolysis of the completed polypeptide from its covalently linked tRNA. For this to occur, the RF must interact with specific A-site components of the active centers within both the small and large ribosomal subunits. In this work, we have used directed hydroxyl radical footprinting to map the ribosomal binding site of the Escherichia coli class I release factor RF2, during translation termination. In the presence of the cognate UGA stop codon, residues flanking the universally conserved (250)GGQ(252) motif of RF2 were each shown to footprint to the large ribosomal subunit, specifically to conserved elements of the peptidyltransferase and GTPase-associated centers. In contrast, residues that flank the putative "peptide anticodon" of RF2, (205)SPF(207), were shown to make a footprint in the small ribosomal subunit at positions within well characterized 16 S rRNA motifs in the vicinity of the decoding center. Within the recently solved crystal structure of E. coli RF2, the GGQ and SPF motifs are separated by 23 A only, a distance that is incompatible with the observed cleavage sites that are up to 100 A apart. Our data suggest that RF2 may undergo gross conformational changes upon ribosome binding, the implications of which are discussed in terms of the mechanism of RF-mediated termination.
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Affiliation(s)
- Debbie-Jane G Scarlett
- Department of Biochemistry and Centre for Gene Research, University of Otago, P. O. Box 56, Dunedin, New Zealand
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Klaholz BP, Pape T, Zavialov AV, Myasnikov AG, Orlova EV, Vestergaard B, Ehrenberg M, van Heel M. Structure of the Escherichia coli ribosomal termination complex with release factor 2. Nature 2003; 421:90-4. [PMID: 12511961 DOI: 10.1038/nature01225] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2002] [Accepted: 10/08/2002] [Indexed: 11/09/2022]
Abstract
Termination of protein synthesis occurs when the messenger RNA presents a stop codon in the ribosomal aminoacyl (A) site. Class I release factor proteins (RF1 or RF2) are believed to recognize stop codons via tripeptide motifs, leading to release of the completed polypeptide chain from its covalent attachment to transfer RNA in the ribosomal peptidyl (P) site. Class I RFs possess a conserved GGQ amino-acid motif that is thought to be involved directly in protein-transfer-RNA bond hydrolysis. Crystal structures of bacterial and eukaryotic class I RFs have been determined, but the mechanism of stop codon recognition and peptidyl-tRNA hydrolysis remains unclear. Here we present the structure of the Escherichia coli ribosome in a post-termination complex with RF2, obtained by single-particle cryo-electron microscopy (cryo-EM). Fitting the known 70S and RF2 structures into the electron density map reveals that RF2 adopts a different conformation on the ribosome when compared with the crystal structure of the isolated protein. The amino-terminal helical domain of RF2 contacts the factor-binding site of the ribosome, the 'SPF' loop of the protein is situated close to the mRNA, and the GGQ-containing domain of RF2 interacts with the peptidyl-transferase centre (PTC). By connecting the ribosomal decoding centre with the PTC, RF2 functionally mimics a tRNA molecule in the A site. Translational termination in eukaryotes is likely to be based on a similar mechanism.
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Affiliation(s)
- Bruno P Klaholz
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AY, UK
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Poole ES, Askarian-Amiri ME, Major LL, McCaughan KK, Scarlett DJG, Wilson DN, Tate WP. Molecular Mimicry in the Decoding of Translational Stop Signals. ACTA ACUST UNITED AC 2003; 74:83-121. [PMID: 14510074 DOI: 10.1016/s0079-6603(03)01011-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
Abstract
Molecular mimicry was a concept that was revived as we understood more about the ligands that bound to the active center of the ribosome, and the characteristics of the active center itself. It has been particularly useful for the termination phase of protein synthesis, because for many years this major process seemed not only to be out of step) with the initiation and elongation phases but also there were no common features of the process between eubacteria and eukaryotes. As the facts that supported molecular mimicry emerged, it was seen that the protein factors that facilitated polypeptide chain release when the decoding of an mRNA was complete had common features with the ligands involved in the other phases. Moreover, now common features and mechanisms began to emerge between the eubacterial and eukaryotic RFs and suddenly there seemed to be remarkable synergy between the external ligands and commonality in at least some features of the mechanistic prnciples. Almost 10 years after molecular mimicry took hold as a framework concept, we can now see that this idea is probably too simple. For example, structural mimicry can be apparent if there are extensive conformational changes either in the ribosome active center or in the ligand itself or, most likely, both. Early indications are that the bacterial RF may indeed undergo extensive conformational changes from its solution structure to achieve this accommodation. Thus, as important if not more important than structural and functional mimicry among the ligands, might be their accomodation of a common single active center made up of at least three parts to carry out a complex series of reactions. One part of the ribosomal active center is committed to decoding, a second is committed to the chemistry of putting the protein together and releasing it, and a third part, perhaps residing in the subdomains, is committed to binding ligands so that they can perform their respective single or multiple functions. It might be more accurate to regard the decoding RF as the cuckoo taking over the nest that was crafted and honed through evolution by another, the tRNA. A somewhat ungainly RF, perhaps bigger in dimensions than the tRNA, is able, nevertheless, like the cuckoo, to maneuvre into the nest. Perhaps it pushes the nest a little out of shape, but is still able to use the site for its own functions of stop signal decoding and for facilitating the release of the polypeptide. The term molecular mimicry has been dominant in the literature for a period of important advances in the understanding of protein synthesis. When the first structures of the ribosome appeared, the concept survived and was seen to be valid still. Now, we are at the stage of understanding the more detailed molecular interactions between ligands and the rRNA in particular, and how subtle changes in localized spatial orientations of atoms occur within these interactions. The simplicity of the original concept of mimicry will inevitably be blurred by this more detailed analysis. Nevertheless, it has provided a significant set of principles that allowed development of experimental programs to enhance our understanding of the dynamic events at this remarkable active site at the interface between the two subunits of this fascinating cell organelle, the ribosome.
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Affiliation(s)
- Elizabeth S Poole
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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15
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Chavatte L, Seit-Nebi A, Dubovaya V, Favre A. The invariant uridine of stop codons contacts the conserved NIKSR loop of human eRF1 in the ribosome. EMBO J 2002; 21:5302-11. [PMID: 12356746 PMCID: PMC129024 DOI: 10.1093/emboj/cdf484] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
To unravel the region of human eukaryotic release factor 1 (eRF1) that is close to stop codons within the ribosome, we used mRNAs containing a single photoactivatable 4-thiouridine (s(4)U) residue in the first position of stop or control sense codons. Accurate phasing of these mRNAs onto the ribosome was achieved by the addition of tRNA(Asp). Under these conditions, eRF1 was shown to crosslink exclusively to mRNAs containing a stop or s(4)UGG codon. A procedure that yielded (32)P-labeled eRF1 deprived of the mRNA chain was developed; analysis of the labeled peptides generated after specific cleavage of both wild-type and mutant eRF1s maps the crosslink in the tripeptide KSR (positions 63-65 of human eRF1) and points to K63 located in the conserved NIKS loop as the main crosslinking site. These data directly show the interaction of the N-terminal (N) domain of eRF1 with stop codons within the 40S ribosomal subunit and provide strong support for the positioning of the eRF1 middle (M) domain on the 60S subunit. Thus, the N and M domains mimic the tRNA anticodon and acceptor arms, respectively.
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Affiliation(s)
- Laurent Chavatte
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7–Paris 6, 2 place Jussieu, F-75251 Paris cedex 05, France and Engelhardt Institute of Molecular Biology, Moscow 119991, Russia Present address: Cleveland Clinic Foundation, 9500 Euclid Avenue NC-10, Cleveland, OH 44195, USA Corresponding author e-mail:
| | - Alim Seit-Nebi
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7–Paris 6, 2 place Jussieu, F-75251 Paris cedex 05, France and Engelhardt Institute of Molecular Biology, Moscow 119991, Russia Present address: Cleveland Clinic Foundation, 9500 Euclid Avenue NC-10, Cleveland, OH 44195, USA Corresponding author e-mail:
| | - Vera Dubovaya
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7–Paris 6, 2 place Jussieu, F-75251 Paris cedex 05, France and Engelhardt Institute of Molecular Biology, Moscow 119991, Russia Present address: Cleveland Clinic Foundation, 9500 Euclid Avenue NC-10, Cleveland, OH 44195, USA Corresponding author e-mail:
| | - Alain Favre
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7–Paris 6, 2 place Jussieu, F-75251 Paris cedex 05, France and Engelhardt Institute of Molecular Biology, Moscow 119991, Russia Present address: Cleveland Clinic Foundation, 9500 Euclid Avenue NC-10, Cleveland, OH 44195, USA Corresponding author e-mail:
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16
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Chavatte L, Frolova L, Kisselev L, Favre A. The polypeptide chain release factor eRF1 specifically contacts the s(4)UGA stop codon located in the A site of eukaryotic ribosomes. ACTA ACUST UNITED AC 2001; 268:2896-904. [PMID: 11358506 DOI: 10.1046/j.1432-1327.2001.02177.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
It has been shown previously [Brown, C.M. & Tate, W.P. (1994) J. Biol. Chem. 269, 33164-33170.] that the polypeptide chain release factor RF2 involved in translation termination in prokaryotes was able to photocrossreact with mini-messenger RNAs containing stop signals in which U was replaced by 4-thiouridine (s4U). Here, using the same strategy we have monitored photocrosslinking to eukaryotic ribosomal components of 14-mer mRNA in the presence of tRNA(f)(Met), and 42-mer mRNA in the presence of tRNA(Asp) (tRNA(Asp) gene transcript). We show that: (a) both 14-mer and 42-mer mRNAs crossreact with ribosomal RNA and ribosomal proteins. The patterns of the crosslinked ribosomal proteins are similar with both mRNAs and sensitive to ionic conditions; (b) the crosslinking patterns obtained with 42-mer mRNAs show characteristic modification upon addition of tRNA(Asp) providing evidence for appropriate mRNA phasing onto the ribosome. Similar changes are not detected with the 14-mer mRNA.tRNA(f)(Met) pairs; (c) when eukaryotic polypeptide chain release factor 1 (eRF1) is added to the ribosome.tRNA(Asp) complex it crossreacts with the 42-mer mRNA containing the s(4)UGA stop codon located in the A site, but not with the s(4)UCA sense codon; this crosslink involves the N-terminal and middle domains of eRF1 but not the C domain which interacts with eukaryotic polypeptide chain release factor 3 (eRF3); (d) addition of eRF3 has no effect on the yield of eRF1-42-mer mRNA crosslinking and eRF3 does not crossreact with 42-mer mRNA. These experiments delineate the in vitro conditions allowing optimal phasing of mRNA on the eukaryotic ribosome and demonstrate a direct and specific contact of 'core' eRF1 and s(4)UGA stop codon within the ribosomal A site.
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Affiliation(s)
- L Chavatte
- Institut Jacques Monod, UMR 7592 CNRS-Universités Paris 7-Paris 6, France
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17
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Liang A, Brünen-Nieweler C, Muramatsu T, Kuchino Y, Beier H, Heckmann K. The ciliate Euplotes octocarinatus expresses two polypeptide release factors of the type eRF1. Gene 2001; 262:161-8. [PMID: 11179680 DOI: 10.1016/s0378-1119(00)00538-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Amplification of macronuclear DNA of the ciliate Euplotes octocarinatus revealed the presence of two genes encoding putative polypeptide release factors (RFs) of the codon specific class-I type. They are named eRF1a and eRF1b, respectively. cDNA amplification revealed that both eRF1 genes are expressed. Determination of their copy numbers showed that they are similarly amplified to a level of about 27,000. The deduced protein sequences of the two genes are 57 and 58% identical with human eRF1 and 79% identical to each other. The gene encoding eRF1b possesses three in-frame UGA codons. This codon is known to encode cysteine in Euplotes; only UAA and UAG are used as stop codons in this organism. The primary structure of the two release factors is analyzed and compared with the primary structure of other eukaryotic release factors including the one of Tetrahymena thermophila which uses only UGA as a stop codon. eRF1a and eRF1b of Euplotes as well as eRF1 of Tetrahymena differ from human eRF1 and other class-I release factors of eukaryotes in a domain recently proposed to be responsible for codon recognition. Based on the changes which we observe in this region and the differential use of the stop codons in these two ciliates we predict the amino acids participating in stop codon recognition in eRF1 release factors.
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Affiliation(s)
- A Liang
- Laboratory of Biotechnology, University, Shanxi, China
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18
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Abstract
Translational termination has been a largely ignored aspect of protein synthesis for many years. However, the recent identification of new release-factor genes, the mapping of release-factor functional sites and in vitro reconstitution experiments have provided a deeper understanding of the termination mechanism. In addition, protein-protein interactions among release factors and with other proteins have been revealed. The three-dimensional structures of a prokaryotic ribosome recycling factor and eukaryotic release factor 1 (eRF1) mimic the shape of transfer RNA, indicating that they bind to the same ribosomal site. Post-termination events in bacteria have been clarified, linking termination, ribosomal recycling and translation initiation.
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Affiliation(s)
- L L Kisselev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova, 117984, Moscow, Russia.
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19
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Poole E, Tate W. Release factors and their role as decoding proteins: specificity and fidelity for termination of protein synthesis. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:1-11. [PMID: 10978500 DOI: 10.1016/s0167-4781(00)00162-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The decoding of stop signals in mRNA requires protein release factors. Two classes of factor are found in both prokaryotes and eukaryotes, a decoding factor and a stimulatory recycling factor. These factors form complexes at the active centre of the ribosome and mimic in overall shape the complexes found at other stages of protein synthesis. The decoding release factor is shaped like a tRNA and has a domain for codon recognition at the decoding site of the ribosome, and a domain for peptidyl-tRNA hydrolysis that is inferred to be near the peptidyltransferase centre. Initial interaction of the decoding factor with the ribosome is a low fidelity event involving multiple contacts with the ribosomal components. A subsequent discrimination step, at present poorly defined, ensures high fidelity of codon recognition.
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Affiliation(s)
- E Poole
- Department of Biochemistry and the Centre for Gene Research, University of Otago, P.O. Box 56, Dunedin, New Zealand
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20
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Tin OF, Rykunova AI, Muranova TA, Toyoda T, Itoa K, Suzuki T, Watanabe K, Garber MB, Nakamura Y. Proteolytic fragmentation of polypeptide release factor 1 of Thermus thermophilus and crystallization of the stable fragments. Biochimie 2000; 82:765-72. [PMID: 11018294 DOI: 10.1016/s0300-9084(00)01149-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Polypeptide release factor one from Thermus thermophilus, ttRF1, was purified and subjected to crystallization. Thin crystalline needles were obtained but their quality was not satisfactory for X-ray diffraction. Stable fragments of ttRF1 suitable for crystallization were screened by limited proteolysis. Three major fragments were produced by thermolysinolysis and analyzed by N-terminal sequencing and electrospray mass spectrometry. They were N-terminal fragments generated by proteolysis at amino acid positions 211, 231 and 292. The corresponding recombinant polypeptides, ttRF1(211), ttRF1(231) and ttRF1(292), were overproduced and subjected to crystallization. Of these polypeptides, ttRF1(292) gave rise to crystals that belong to P3(1) (or P3(2)) space group with unit cell parameters a = b = 64. 5 A, c = 86.6 A and diffract up to 7 A resolution.
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Affiliation(s)
- O F Tin
- Institute of Protein Research, Russian Academy of Sciences, Moscow Region, Pushchino, Russia
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21
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Askarian-Amiri ME, Pel HJ, Guévremont D, McCaughan KK, Poole ES, Sumpter VG, Tate WP. Functional characterization of yeast mitochondrial release factor 1. J Biol Chem 2000; 275:17241-8. [PMID: 10748224 DOI: 10.1074/jbc.m910448199] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The yeast Saccharomyces cerevisiae mitochondrial release factor was expressed from the cloned MRF1 gene, purified from inclusion bodies, and refolded to give functional activity. The gene encoded a factor with release activity that recognized cognate stop codons in a termination assay with mitochondrial ribosomes and in an assay with Escherichia coli ribosomes. The noncognate stop codon, UGA, encoding tryptophan in mitochondria, was recognized weakly in the heterologous assay. The mitochondrial release factor 1 protein bound to bacterial ribosomes and formed a cross-link with the stop codon within a mRNA bound in a termination complex. The affinity was strongly dependent on the identity of stop signal. Two alleles of MRF1 that contained point mutations in a release factor 1 specific region of the primary structure and that in vivo compensated for mutations in the decoding site rRNA of mitochondrial ribosomes were cloned, and the expressed proteins were purified and refolded. The variant proteins showed impaired binding to the ribosome compared with mitochondrial release factor 1. This structural region in release factors is likely to be involved in codon-dependent specific ribosomal interactions.
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Affiliation(s)
- M E Askarian-Amiri
- Department of Biochemistry and Centre for Gene Research, University of Otago, P. O. Box 56, 9015 Dunedin, New Zealand
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22
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Class-1 polypeptide chain release factors are structurally and functionally similar to suppressor tRNAs and comprise different structural-functional families of prokaryotic/mitochondrial and eukaryotic/archaebacterial factors. Mol Biol 2000. [DOI: 10.1007/bf02759667] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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23
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Abstract
The two translational release factors of prokaryotes, RF1 and RF2, catalyse the termination of polypeptide synthesis at UAG/UAA and UGA/UAA stop codons, respectively. However, how these polypeptide release factors read both non-identical and identical stop codons is puzzling. Here we describe the basis of this recognition. Swaps of each of the conserved domains between RF1 and RF2 in an RF1-RF2 hybrid led to the identification of a domain that could switch recognition specificity. A genetic selection among clones encoding random variants of this domain showed that the tripeptides Pro-Ala-Thr and Ser-Pro-Phe determine release-factor specificity in vivo in RF1 and RF2, respectively. An in vitro release study of tripeptide variants indicated that the first and third amino acids independently discriminate the second and third purine bases, respectively. Analysis with stop codons containing base analogues indicated that the C2 amino group of purine may be the primary target of discrimination of G from A. These findings show that the discriminator tripeptide of bacterial release factors is functionally equivalent to that of the anticodon of transfer RNA, irrespective of the difference between protein and RNA.
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Affiliation(s)
- K Ito
- Department of Tumor Biology, Institute of Medical Science, University of Tokyo, Japan
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24
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Song H, Mugnier P, Das AK, Webb HM, Evans DR, Tuite MF, Hemmings BA, Barford D. The crystal structure of human eukaryotic release factor eRF1--mechanism of stop codon recognition and peptidyl-tRNA hydrolysis. Cell 2000; 100:311-21. [PMID: 10676813 DOI: 10.1016/s0092-8674(00)80667-4] [Citation(s) in RCA: 339] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The release factor eRF1 terminates protein biosynthesis by recognizing stop codons at the A site of the ribosome and stimulating peptidyl-tRNA bond hydrolysis at the peptidyl transferase center. The crystal structure of human eRF1 to 2.8 A resolution, combined with mutagenesis analyses of the universal GGQ motif, reveals the molecular mechanism of release factor activity. The overall shape and dimensions of eRF1 resemble a tRNA molecule with domains 1, 2, and 3 of eRF1 corresponding to the anticodon loop, aminoacyl acceptor stem, and T stem of a tRNA molecule, respectively. The position of the essential GGQ motif at an exposed tip of domain 2 suggests that the Gln residue coordinates a water molecule to mediate the hydrolytic activity at the peptidyl transferase center. A conserved groove on domain 1, 80 A from the GGQ motif, is proposed to form the codon recognition site.
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MESH Headings
- Amino Acid Sequence
- Codon, Terminator
- Crystallography
- Humans
- Hydrolysis
- Models, Molecular
- Molecular Mimicry
- Molecular Sequence Data
- Peptide Chain Termination, Translational
- Peptide Termination Factors/chemistry
- Peptide Termination Factors/genetics
- RNA, Transfer/chemistry
- RNA, Transfer/metabolism
- RNA, Transfer, Amino Acyl/chemistry
- RNA, Transfer, Amino Acyl/metabolism
- Recombinant Proteins/chemistry
- Sequence Homology, Amino Acid
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Affiliation(s)
- H Song
- Section of Structural Biology, Institute of Cancer Research, London, United Kingdom
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25
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Yoshimura K, Ito K, Nakamura Y. Amber (UAG) suppressors affected in UGA/UAA-specific polypeptide release factor 2 of bacteria: genetic prediction of initial binding to ribosome preceding stop codon recognition. Genes Cells 1999; 4:253-66. [PMID: 10421836 DOI: 10.1046/j.1365-2443.1999.00260.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Prokaryotic translational release factors, RF1 and RF2, catalyse protein release at UAG/UAA and UGA/UAA stop codons, respectively. Mutations in RF1 and RF2 are known to cause non-sense suppression for UAG (amber) and UGA (opal) codons, respectively, and they do not exert a reciprocal ('cross') suppression phenotype. We aimed to isolate RF mutants of such cross-suppression activity, which we designated 'Csu' phenotype in this paper. RESULTS Using a lacZ (UAG) reporter, we selected amber suppressor alleles occurring in the plasmid-bearing RF2 gene of Salmonella typhimurium. Of nine such RF2 csu alleles, five were mis-sense mutations and four were non-sense mutations. The former mis-sense mutants retained the RF2 activity and catalysed UGA termination both in vivo and in vitro. RF2 C-terminal deletions equivalent to the non-sense alleles exerted amber suppression as well as opal suppression activity. Moreover, the equivalent RF1 segments also showed both the suppression phenotypes. CONCLUSIONS All the csu mutations were mapped at the C-terminal half of RF2 and are strikingly coincident with the highly conservative amino acids, suggesting that they affect the conserved function of bacterial RFs. We propose here that there should be an 'initial binding' step of RFs to the ribosome, preceding stop codon recognition ('initial binding' hypothesis) and that the N-terminal RF domain(s), that are truncated or affected by the csu mutations, are responsible for this step and interfere with the proper functioning of cognate release factors on the ribosome.
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Affiliation(s)
- K Yoshimura
- Department of Tumor Biology, The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo 108-8639, Japan
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26
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McCaughan KK, Poole ES, Pel HJ, Mansell JB, Mannering SA, Tate WP. Efficient in vitro translational termination in Escherichia coli is constrained by the orientations of the release factor, stop signal and peptidyl-tRNA within the termination complex. Biol Chem 1998; 379:857-66. [PMID: 9705149 DOI: 10.1515/bchm.1998.379.7.857] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
There have been contrasting reports of whether the positioning of a translational stop signal immediately after a start codon in a single oligonucleotide can act as a model template to support efficient in vitro termination. This paradox stimulated this study of what determines the constraints on the positioning of the components in the termination complex. The mini mRNA, AUGUGAA, was unable to support efficient in vitro termination in contrast to separate AUG/UGA(A) codons, unless the ribosomal interaction of the stop signal with the decoding factor, release factor 2, was stimulated with ethanol or with nucleotide-free release factor 3, or by using (L11-)-ribosomes which have a higher affinity for release factor 2, or unless the fMet-tRNA was first bound to 30S subunits independently of the mini mRNA. An additional triplet stop codon could restore activity of the mini mRNA, indicating that its recognition was not sterically restrained by the stop signal already within it. This suggests that in an initiation complex an adjoining start/stop signal is not positioned to support efficient decoding by release factor unless it is separated from the start codon. Site-directed crosslinking from mRNAs to components of the termination complex has shown that mRNA elements like the Shine-Dalgarno sequence and the codon preceding the stop signal can affect the crosslinking to release factor, and presumably the orientation of the signal to the factor.
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Affiliation(s)
- K K McCaughan
- Department of Biochemistry and Centre for Gene Research, University of Otago, Dunedin, New Zealand
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27
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Uno M, Ito K, Nakamura Y. Functional specificity of amino acid at position 246 in the tRNA mimicry domain of bacterial release factor 2. Biochimie 1996; 78:935-43. [PMID: 9150870 DOI: 10.1016/s0300-9084(97)86715-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The termination of protein synthesis in bacteria requires codon-specific polypeptide release factors RF-1 (UAG/UAA specific) and RF-2 (UGA/UAA specific). We have proposed that release factors mimic tRNA and recognize the stop codon for polypeptide release (Nakamura et al (1996) Cell 87, 147-150). In contrast to the textbook view, genetic experiments have indicated that Escherichia coli RF-2 terminates translation very weakly at UAA while Salmonella RF-2 decodes this signal efficiently. Moreover, an excess of E coli RF-2 was toxic to cells while an excess of Salmonella RF-2 was not. These two RF-2 proteins are identical except for 16 out of 365 amino acids. Fragment swap experiments and site-directed mutagenesis revealed that a residue at position 246 is solely responsible for these two phenotypes. Upon substituting Ala (equivalent to Salmonella RF-2) for Thr-246 of E coli RF-2, the protein acquired increased release activity for UAA as well as for UGA. These results led us to conclude that E coli RF-2 activity is potentially weak and that the amino acid at position 246 plays a crucial role, not for codon discrimination, but for stop codon recognition or polypeptide release, presumably constituting an essential moiety of tRNA mimicry or interacting with peptidyltransferase centers of the ribosome.
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Affiliation(s)
- M Uno
- Department of Tumor Biology, University of Tokyo, Japan
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28
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Tate WP, Poole ES, Mannering SA. Hidden infidelities of the translational stop signal. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1996; 52:293-335. [PMID: 8821264 DOI: 10.1016/s0079-6603(08)60970-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- W P Tate
- Department of Biochemistry and Center for Gene Research, University of Otago, Dunedin, New Zealand
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29
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Tate WP, Dalphin ME, Pel HJ, Mannering SA. The stop signal controls the efficiency of release factor-mediated translational termination. GENETIC ENGINEERING 1996; 18:157-82. [PMID: 8785120 DOI: 10.1007/978-1-4899-1766-9_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- W P Tate
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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30
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Brown CM, Tate WP. Direct recognition of mRNA stop signals by Escherichia coli polypeptide chain release factor two. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(20)30112-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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