scholarly journals Complementary roles of initiation factor 1 and ribosome recycling factor in 70S ribosome splitting

2008 ◽  
Vol 27 (12) ◽  
pp. 1706-1717 ◽  
Author(s):  
Michael Y Pavlov ◽  
Ayman Antoun ◽  
Martin Lovmar ◽  
Måns Ehrenberg
BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Soma Jana ◽  
Partha P. Datta

Abstract Background Protein synthesis is a cellular process that takes place through the successive translation events within the ribosome by the event-specific protein factors, namely, initiation, elongation, release, and recycling factors. In this regard, we asked the question about how similar are those translation factors to each other from a wide variety of bacteria? Hence, we did a thorough in silico study of the translation factors from 495 bacterial sp., and 4262 amino acid sequences by theoretically measuring their pI and MW values that are two determining factors for distinguishing individual proteins in 2D gel electrophoresis in experimental procedures. Then we analyzed the output from various angles. Results Our study revealed the fact that it’s not all same, or all random, but there are distinct orders and the pI values of translation factors are translation event specific. We found that the translation initiation factors are mainly basic, whereas, elongation and release factors that interact with the inter-subunit space of the intact 70S ribosome during translation are strictly acidic across bacterial sp. These acidic elongation factors and release factors contain higher frequencies of glutamic acids. However, among all the translation factors, the translation initiation factor 2 (IF2) and ribosome recycling factor (RRF) showed variable pI values that are linked to the order of phylogeny. Conclusions From the results of our study, we conclude that among all the bacterial translation factors, elongation and release factors are more conserved in terms of their pI values in comparison to initiation and recycling factors. Acidic properties of these factors are independent of habitat, nature, and phylogeny of the bacterial species. Furthermore, irrespective of the different shapes, sizes, and functions of the elongation and release factors, possession of the strictly acidic pI values of these translation factors all over the domain Bacteria indicates that the acidic nature of these factors is a necessary criterion, perhaps to interact into the partially enclosed rRNA rich inter-subunit space of the translating 70S ribosome.


2007 ◽  
Vol 189 (8) ◽  
pp. 3147-3155 ◽  
Author(s):  
Ming Gong ◽  
Luis R. Cruz-Vera ◽  
Charles Yanofsky

ABSTRACT Upon tryptophan induction of tna operon expression in Escherichia coli, the leader peptidyl-tRNA, TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document} , resists cleavage, resulting in ribosome stalling at the tnaC stop codon. This stalled ribosome blocks Rho factor binding and action, preventing transcription termination in the tna operon's leader region. Plasmid-mediated overexpression of tnaC was previously shown to inhibit cell growth by reducing uncharged \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document}  availability. Which factors relieve ribosome stalling, facilitate TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document}  cleavage, and relieve growth inhibition were addressed in the current study. In strains containing the chromosomal tna operon and lacking a tnaC plasmid, the overproduction of ribosome recycling factor (RRF) and release factor 3 (RF3) reduced tna operon expression. Their overproduction in vivo also increased the rate of cleavage of TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document} , relieving the growth inhibition associated with plasmid-mediated tnaC overexpression. The overproduction of elongation factor G or initiation factor 3 did not have comparable effects, and tmRNA was incapable of attacking TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document}  in stalled ribosome complexes. The stability of TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document}  was increased appreciably in strains deficient in RRF and RF3 or deficient in peptidyl-tRNA hydrolase. These findings reveal the existence of a natural mechanism whereby an amino acid, tryptophan, binds to ribosomes that have just completed the synthesis of TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document} . Bound tryptophan inhibits RF2-mediated cleavage of TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document} , resulting in the stalling of the ribosome translating tnaC mRNA. This stalling results in increased transcription of the structural genes of the tna operon. RRF and RF3 then bind to this stalled ribosome complex and slowly release TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document} . This release allows ribosome recycling and permits the cleavage of TnaC- \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(tRNA_{2}^{Pro}\) \end{document}  by peptidyl-tRNA hydrolase.


2020 ◽  
Author(s):  
SOMA JANA ◽  
Partha Pratim Datta

Abstract Background Protein synthesis is a cellular process that takes place through the successive translation events within the ribosome with the help of the event-specific protein factors, namely, initiation, elongation, release, and recycling factors. The translation process is fundamental to all organisms living in the wide variety of environments. In this regard, we asked the questions about how similar are those translation factors to each other from a wide variety of bacteria? Hence, we did a thorough in silico study of the translation factors from 495 bacterial sp., and 4262 amino acid sequences, wherein we theoretically measured their pI and MW values that are the two determining factors for distinguishing individual proteins in 2D gel electrophoresis. Then we analyzed the output from various angles. Results Our study revealed that, not all the pI values are same or random, but there is a distinct order, such that the pI values of translation factors are translation event specific. We found that the translation initiation factors are mainly basic, whereas, elongation and release factors that interact with the inter-subunit space of the intact 70S ribosome during translation are strictly acidic. Further analysis revealed that the acidic property of those factors is due to the higher frequencies of glutamic acids. However, two translation factors, the translation initiation factor 2 (IF2) and the ribosome recycling factor (RRF) showed variable pI values. Remarkably, the variability of the pI values of these two factors showed distinct lineage with the order of phylogeny. Conclusion From our results we conclude that, among all the bacterial translation factors, elongation and release factors are more conserved in terms of their pI values in comparison to initiation and recycling factors. Acidic properties of these factors are independent of habitat, nature, or the phylogeny of the bacterial species. Furthermore; irrespective of the different shapes, sizes, and functions of the elongation and release factors, possession of their strictly acidic pI values indicate that the acidic nature of these factors is a necessary criterion, perhaps to interact into the partially enclosed rRNA rich inter-subunit space of the translating 70S ribosome.


2008 ◽  
Vol 376 (5) ◽  
pp. 1334-1347 ◽  
Author(s):  
Raj D. Pai ◽  
Wen Zhang ◽  
Barbara S. Schuwirth ◽  
Go Hirokawa ◽  
Hideko Kaji ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document