Ribosome run through of the termination codon in the absence of the ribosome releasing factor

Ogawa, Koichi; Kaji, Akira

doi:10.1016/0005-2787(75)90266-x

Cited by 11 publications

(7 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…IF3 assists this reaction by preventing the re-association of split subunits into the 70S ribosome, in confirmation of the observations by others [9, 10, 15, 16, 34, 39, 40] that RRF/EF-G indeed splits 70S ribosomes. We emphasize that anti-association activity of IF3 is an old well established observations [39, 40] and we simply confirmed this fact in our system, In this study, we showed that, using PoTC derived from natural polysomes that are not near a SD sequence, RRF and EF-G were able to split the PoTC into subunits even in the absence of IF3 (Fig 7A, open circles).…”

Section: Discussionsupporting

confidence: 88%

“…In our prior studies, to overcome the problem that the substrate does not have the real termination codon at the A-site, we constructed the PoTC, which occurs during the infection of E . coli with R17 phage having the amber mutation on the seventh codon of the coat cistron [34]. This complex is the only natural PoTC used thus far for the reaction of RRF and EF-G. We confirmed every finding obtained with our model PoTC with this natural system.…”

Section: Discussionsupporting

confidence: 81%

See 1 more Smart Citation

Chemical and structural characterization of a model Post-Termination Complex (PoTC) for the ribosome recycling reaction: Evidence for the release of the mRNA by RRF and EF-G

Iwakura

Yokoyama²,

Quaglia

et al. 2017

PLoS ONE

Self Cite

View full text Add to dashboard Cite

A model Post-Termination Complex (PoTC) used for the discovery of Ribosome Recycling Factor (RRF) was purified and characterized by cryo-electron microscopic analysis and biochemical methods. We established that the model PoTC has mostly one tRNA, at the P/E or P/P position, together with one mRNA. The structural studies were supported by the biochemical measurement of bound tRNA and mRNA. Using this substrate, we establish that the release of tRNA, release of mRNA and splitting of ribosomal subunits occur during the recycling reaction. Order of these events is tRNA release first followed by mRNA release and splitting almost simultaneously. Moreover, we demonstrate that IF3 is not involved in any of the recycling reactions but simply prevents the re-association of split ribosomal subunits. Our finding demonstrates that the important function of RRF includes the release of mRNA, which is often missed by the use of a short ORF with the Shine-Dalgarno sequence near the termination site.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Discussionsupporting

confidence: 81%

Chemical and structural characterization of a model Post-Termination Complex (PoTC) for the ribosome recycling reaction: Evidence for the release of the mRNA by RRF and EF-G

Iwakura

Yokoyama²,

Quaglia

et al. 2017

PLoS ONE

Self Cite

View full text Add to dashboard Cite

show abstract

“…The hexapeptide is released from the ribosome-amB2 R17 RNA complex by termination factors (2)(3)(4)(5) and possibly by an additional factor called "rescue factor" (6). Subsequently, ribosome-releasing factor (RR factor) releases ribosomes from mRNA at the amber codon (7)(8)(9). In the absence ofthis factor, this mutant RNA is translated even without suppressor tRNA (8,9), leading to synthesis of polypeptide(s) with a molecular weight of 13,800, very close to that of the authentic R17 coat protein.…”

mentioning

confidence: 99%

“…Subsequently, ribosome-releasing factor (RR factor) releases ribosomes from mRNA at the amber codon (7)(8)(9). In the absence ofthis factor, this mutant RNA is translated even without suppressor tRNA (8,9), leading to synthesis of polypeptide(s) with a molecular weight of 13,800, very close to that of the authentic R17 coat protein.…”

mentioning

confidence: 99%

Reinitiation of translation from the triplet next to the amber termination codon in the absence of ribosome-releasing factor.

Ryoji¹,

Berland²,

Kaji³

1981

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Ribosome releasing factor (RR factor) releases ribosomes from mRNA at the termination codon in Escherichia coli. In the absence of this factor, polypeptides with molecular weights very close to the molecular weight of bacteriophage R17 coat protein were synthesized in vitro under the direction of a mutant R17 phage RNA having an amber mutation at codon 7 of the coat cistron. The major coat-protein-like product shared all the R17 coat protein sequence except that the seven NH2-terminal amino acids were missing. The minor product had the complete coat protein sequence starting from formylmethionine except for a probable amino acid substitution at codon 7 (UAG). Addition of RR factor inhibited the synthesis of the major protein. These results indicate that, in the absence of RR factor, the ribosome that has released the NH2-terminal hexapeptide at the amber codon stays on the mRNA and subsequently reinitiates translation "in phase" immediately after the amber codon without formylmethionine.A mutant R17 phage amB2 has an amber mutation at the seventh triplet of the coat cistron (1), and suppressor tRNA is needed to produce complete coat protein. In the absence of suppressor tRNA, this amB2 R17 RNA directs synthesis of only NH2-terminal hexapeptide proximal to the amber codon besides the polypeptides coded for by the other genes. The hexapeptide is released from the ribosome-amB2 R17 RNA complex by termination factors (2-5) and possibly by an additional factor called "rescue factor" (6). Subsequently, ribosome-releasing factor (RR factor) releases ribosomes from mRNA at the amber codon (7-9). In the absence ofthis factor, this mutant RNA is translated even without suppressor tRNA (8, 9), leading to synthesis of polypeptide(s) with a molecular weight of 13,800, very close to that of the authentic R17 coat protein.In this paper, we demonstrate that, in the absence ofRR factor, translation is reinitiated "in phase" immediately after the amber codon without formylmethionine, resulting in synthesis of this coat-protein-like product (CPP). The implication of this finding is discussed in connection with possible ribosome movement from one cistron to the next in translation of bacterial polycistronic mRNA. MATERIALS AND METHODSIn Vitro Translation System. All in vitro translations were carried out in a reconstituted system of Escherichia coli cell extract from which RR factor had been removed as described (7,9). Where indicated, 6.0 ,ug of electrophoretically homogeneous RR factor purified from the ribosomal wash (9) was added per 70 ,u1 ofreaction mixture. For the peptide mapping, 62-94 ACi (1 Ci = 3.7 X 10'°becquerels) of [ S]methionine were used per 70 1.l ofreaction mixture. For the NH2-terminal analysis by the fluorodinitrobenzene method, a mixture of 16 "'C-labeled amino acids (total, 1.9 ACi/70 pl of reaction mixture) and nonlabeled glutamine, asparagine, cysteine, and tryptophan at 0.01 mM each was added. For determination of the equence of the NH2-terminal region of the CPP, a mixture of 18 "4C-amino acids ...

show abstract

“…The importance of RRF in the protein synthesis process was indicated by the following in vitro experiments: (i) it caused a 7-fold stimulation ofthe synthesis ofboth phage R17 coat protein and phage T4 lysozyme (8), (ii) it was necessary for the maximum synthesis of,-galactosidase (6,12), and (iii) its omission led to unwanted initiation of protein synthesis immediately adjacent to the translational termination signal (8,13,14). Despite these compelling data, a question remained about the essentiality ofthis factor.…”

mentioning

confidence: 99%

Ribosome recycling factor (ribosome releasing factor) is essential for bacterial growth.

Janosi

Shimizu

Kaji

1994

Proc. Natl. Acad. Sci. U.S.A.

111

104

View full text Add to dashboard Cite

Ribosome releasing factor, product of thefn' gene in Escherichia col, is responsible for dissociation of ribosomes from mRNA after the termination of translation. It functions to "recycle" ribosomes and is renamed ribosome recycling factor in this paper. An E. coil strain was constructed (MC1061-2), which carried frame-shifted firr in the chromosome and wild-type frr on a temperature-sensitive plasmid.MC1061-2 is temperature-sensitive in its growth and does not segregate its fir-carrying plasmid under the plasmid incompatibility pressure. In contrast, isogenic E. coil carrying wildtype frr in the chromosome and mutated firr on the temperature-sensitive plasmid is not temperature-sensitive in its growth and segregates its plasmid from incompatible plasmids.

show abstract

Ribosome run through of the termination codon in the absence of the ribosome releasing factor

Cited by 11 publications

References 26 publications

Chemical and structural characterization of a model Post-Termination Complex (PoTC) for the ribosome recycling reaction: Evidence for the release of the mRNA by RRF and EF-G

Chemical and structural characterization of a model Post-Termination Complex (PoTC) for the ribosome recycling reaction: Evidence for the release of the mRNA by RRF and EF-G

Reinitiation of translation from the triplet next to the amber termination codon in the absence of ribosome-releasing factor.

Ribosome recycling factor (ribosome releasing factor) is essential for bacterial growth.

Contact Info

Product

Resources

About