1
|
Horvath A, Janapala Y, Woodward K, Mahmud S, Cleynen A, Gardiner E, Hannan R, Eyras E, Preiss T, Shirokikh N. Comprehensive translational profiling and STE AI uncover rapid control of protein biosynthesis during cell stress. Nucleic Acids Res 2024; 52:7925-7946. [PMID: 38721779 PMCID: PMC11260467 DOI: 10.1093/nar/gkae365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/21/2024] [Accepted: 04/25/2024] [Indexed: 07/23/2024] Open
Abstract
Translational control is important in all life, but it remains a challenge to accurately quantify. When ribosomes translate messenger (m)RNA into proteins, they attach to the mRNA in series, forming poly(ribo)somes, and can co-localize. Here, we computationally model new types of co-localized ribosomal complexes on mRNA and identify them using enhanced translation complex profile sequencing (eTCP-seq) based on rapid in vivo crosslinking. We detect long disome footprints outside regions of non-random elongation stalls and show these are linked to translation initiation and protein biosynthesis rates. We subject footprints of disomes and other translation complexes to artificial intelligence (AI) analysis and construct a new, accurate and self-normalized measure of translation, termed stochastic translation efficiency (STE). We then apply STE to investigate rapid changes to mRNA translation in yeast undergoing glucose depletion. Importantly, we show that, well beyond tagging elongation stalls, footprints of co-localized ribosomes provide rich insight into translational mechanisms, polysome dynamics and topology. STE AI ranks cellular mRNAs by absolute translation rates under given conditions, can assist in identifying its control elements and will facilitate the development of next-generation synthetic biology designs and mRNA-based therapeutics.
Collapse
Affiliation(s)
- Attila Horvath
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
| | - Yoshika Janapala
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
| | - Katrina Woodward
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
| | - Shafi Mahmud
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
| | - Alice Cleynen
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
- Institut Montpelliérain Alexander Grothendieck, Université de Montpellier, CNRS, Montpellier, France
| | - Elizabeth E Gardiner
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The National Platelet Research and Referral Centre, The Australian National University, Canberra, ACT 2601, Australia
| | - Ross D Hannan
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3010, Australia
- Peter MacCallum Cancer Centre, Melbourne 3000, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton 3800, Australia
- School of Biomedical Sciences, University of Queensland, St Lucia 4067, Australia
| | - Eduardo Eyras
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Centre for Computational Biomedical Sciences, The Australian National University, Canberra, ACT 2601, Australia
- EMBL Australia Partner Laboratory Network at the Australian National University, Canberra, ACT 2601, Australia
| | - Thomas Preiss
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Nikolay E Shirokikh
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, and The Shine-Dalgarno Centre for RNA Innovation, The Australian National University, Canberra, ACT 2601, Australia
| |
Collapse
|
2
|
Huang T, Choi J, Prabhakar A, Puglisi JD, Petrov A. Partial spontaneous intersubunit rotations in pretranslocation ribosomes. Proc Natl Acad Sci U S A 2023; 120:e2114979120. [PMID: 37801472 PMCID: PMC10576065 DOI: 10.1073/pnas.2114979120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 08/29/2023] [Indexed: 10/08/2023] Open
Abstract
The two main steps of translation, peptidyl transfer, and translocation are accompanied by counterclockwise and clockwise rotations of the large and small ribosomal subunits with respect to each other. Upon peptidyl transfer, the small ribosomal subunit rotates counterclockwise relative to the large subunit, placing the ribosome into the rotated conformation. Simultaneously, tRNAs move into the hybrid conformation, and the L1 stalk moves inward toward the P-site tRNA. The conformational dynamics of pretranslocation ribosomes were extensively studied by ensemble and single-molecule methods. Different experimental modalities tracking ribosomal subunits, tRNAs, and the L1 stalk showed that pretranslocation ribosomes undergo spontaneous conformational transitions. Thus, peptidyl transfer unlocks the ribosome and decreases an energy barrier for the reverse ribosome rotation during translocation. However, the tracking of translation with ribosomes labeled at rRNA helices h44 and H101 showed a lack of spontaneous rotations in pretranslocation complexes. Therefore, reverse intersubunit rotations occur during EF-G catalyzed translocation. To reconcile these views, we used high-speed single-molecule microscopy to follow translation in real time. We showed spontaneous rotations in puromycin-released h44-H101 dye-labeled ribosomes. During elongation, the h44-H101 ribosomes undergo partial spontaneous rotations. Spontaneous rotations in h44-H101-labeled ribosomes are restricted prior to aminoacyl-tRNA binding. The pretranslocation h44-H101 ribosomes spontaneously exchanged between three different rotational states. This demonstrates that peptidyl transfer unlocks spontaneous rotations and pretranslocation ribosomes can adopt several thermally accessible conformations, thus supporting the Brownian model of translocation.
Collapse
Affiliation(s)
- Tianhan Huang
- Department of Biological Sciences, Auburn University, Auburn, AL36849
| | - Junhong Choi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA94305
| | - Arjun Prabhakar
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA94305
| | - Joseph D. Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA94305
| | - Alexey Petrov
- Department of Biological Sciences, Auburn University, Auburn, AL36849
| |
Collapse
|
3
|
Iizuka R, Yamazaki H, Uemura S. Zero-mode waveguides and nanopore-based sequencing technologies accelerate single-molecule studies. Biophys Physicobiol 2022; 19:e190032. [DOI: 10.2142/biophysico.bppb-v19.0032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/26/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
- Ryo Iizuka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo
| | - Hirohito Yamazaki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo
| | - Sotaro Uemura
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo
| |
Collapse
|
4
|
Seefeldt AC, Aguirre Rivera J, Johansson M. Direct Measurements of Erythromycin's Effect on Protein Synthesis Kinetics in Living Bacterial Cells. J Mol Biol 2021; 433:166942. [PMID: 33744313 DOI: 10.1016/j.jmb.2021.166942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 03/09/2021] [Accepted: 03/09/2021] [Indexed: 10/21/2022]
Abstract
Macrolide antibiotics, such as erythromycin, bind to the nascent peptide exit tunnel (NPET) of the bacterial ribosome and modulate protein synthesis depending on the nascent peptide sequence. Whereas in vitro biochemical and structural methods have been instrumental in dissecting and explaining the molecular details of macrolide-induced peptidyl-tRNA drop-off and ribosome stalling, the dynamic effects of the drugs on ongoing protein synthesis inside live bacterial cells are far less explored. In the present study, we used single-particle tracking of dye-labeled tRNAs to study the kinetics of mRNA translation in the presence of erythromycin, directly inside live Escherichia coli cells. In erythromycin-treated cells, we find that the dwells of elongator tRNAPhe on ribosomes extend significantly, but they occur much more seldom. In contrast, the drug barely affects the ribosome binding events of the initiator tRNAfMet. By overexpressing specific short peptides, we further find context-specific ribosome binding dynamics of tRNAPhe, underscoring the complexity of erythromycin's effect on protein synthesis in bacterial cells.
Collapse
Affiliation(s)
| | | | - Magnus Johansson
- Department of Cell and Molecular Biology, Uppsala University, Sweden.
| |
Collapse
|
5
|
Variability in mRNA translation: a random matrix theory approach. Sci Rep 2021; 11:5300. [PMID: 33674667 PMCID: PMC7970873 DOI: 10.1038/s41598-021-84738-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/19/2021] [Indexed: 01/31/2023] Open
Abstract
The rate of mRNA translation depends on the initiation, elongation, and termination rates of ribosomes along the mRNA. These rates depend on many "local" factors like the abundance of free ribosomes and tRNA molecules in the vicinity of the mRNA molecule. All these factors are stochastic and their experimental measurements are also noisy. An important question is how protein production in the cell is affected by this considerable variability. We develop a new theoretical framework for addressing this question by modeling the rates as identically and independently distributed random variables and using tools from random matrix theory to analyze the steady-state production rate. The analysis reveals a principle of universality: the average protein production rate depends only on the of the set of possible values that the random variable may attain. This explains how total protein production can be stabilized despite the overwhelming stochasticticity underlying cellular processes.
Collapse
|
6
|
Jednačak T, Mikulandra I, Novak P. Advanced Methods for Studying Structure and Interactions of Macrolide Antibiotics. Int J Mol Sci 2020; 21:E7799. [PMID: 33096889 PMCID: PMC7589898 DOI: 10.3390/ijms21207799] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 10/09/2020] [Accepted: 10/19/2020] [Indexed: 11/17/2022] Open
Abstract
Macrolide antibiotics are macrocyclic compounds that are clinically used and prescribed for the treatment of upper and lower respiratory tract infections. They inhibit the synthesis of bacterial proteins by reversible binding to the 23S rRNA at or near the peptidyl transferase center. However, their excellent antibacterial profile was largely compromised by the emergence of bacterial resistance. Today, fighting resistance to antibiotics is one of the greatest challenges in medicinal chemistry. Considering various physicochemical properties of macrolides, understanding their structure and interactions with macromolecular targets is crucial for the design of new antibiotics efficient against resistant pathogens. The solid-state structures of some macrolide-ribosome complexes have recently been solved, throwing new light on the macrolide binding mechanisms. On the other hand, a combination of NMR spectroscopy and molecular modeling calculations can be applied to study free and bound conformations in solution. In this article, a description of advanced physicochemical methods for elucidating the structure and interactions of macrolide antibiotics in solid state and solution will be provided, and their principal advantages and drawbacks will be discussed.
Collapse
Affiliation(s)
- Tomislav Jednačak
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia;
| | | | - Predrag Novak
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia;
| |
Collapse
|
7
|
Gorin G, Wang M, Golding I, Xu H. Stochastic simulation and statistical inference platform for visualization and estimation of transcriptional kinetics. PLoS One 2020; 15:e0230736. [PMID: 32214380 PMCID: PMC7098607 DOI: 10.1371/journal.pone.0230736] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/06/2020] [Indexed: 12/20/2022] Open
Abstract
Recent advances in single-molecule fluorescent imaging have enabled quantitative measurements of transcription at a single gene copy, yet an accurate understanding of transcriptional kinetics is still lacking due to the difficulty of solving detailed biophysical models. Here we introduce a stochastic simulation and statistical inference platform for modeling detailed transcriptional kinetics in prokaryotic systems, which has not been solved analytically. The model includes stochastic two-state gene activation, mRNA synthesis initiation and stepwise elongation, release to the cytoplasm, and stepwise co-transcriptional degradation. Using the Gillespie algorithm, the platform simulates nascent and mature mRNA kinetics of a single gene copy and predicts fluorescent signals measurable by time-lapse single-cell mRNA imaging, for different experimental conditions. To approach the inverse problem of estimating the kinetic parameters of the model from experimental data, we develop a heuristic optimization method based on the genetic algorithm and the empirical distribution of mRNA generated by simulation. As a demonstration, we show that the optimization algorithm can successfully recover the transcriptional kinetics of simulated and experimental gene expression data. The platform is available as a MATLAB software package at https://data.caltech.edu/records/1287.
Collapse
Affiliation(s)
- Gennady Gorin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, United States of America
| | - Mengyu Wang
- Department of Physics, Grainger College of Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Ido Golding
- Department of Physics, Grainger College of Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Heng Xu
- School of Physics and Astronomy, Shanghai Jiao Tong University, Minhang District, Shanghai, China
- Institute of Natural Sciences, Shanghai Jiao Tong University, Minhang District, Shanghai, China
- * E-mail:
| |
Collapse
|
8
|
Verma M, Choi J, Cottrell KA, Lavagnino Z, Thomas EN, Pavlovic-Djuranovic S, Szczesny P, Piston DW, Zaher HS, Puglisi JD, Djuranovic S. A short translational ramp determines the efficiency of protein synthesis. Nat Commun 2019; 10:5774. [PMID: 31852903 PMCID: PMC6920384 DOI: 10.1038/s41467-019-13810-1] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 11/25/2019] [Indexed: 01/26/2023] Open
Abstract
Translation initiation is a major rate-limiting step for protein synthesis. However, recent studies strongly suggest that the efficiency of protein synthesis is additionally regulated by multiple factors that impact the elongation phase. To assess the influence of early elongation on protein synthesis, we employed a library of more than 250,000 reporters combined with in vitro and in vivo protein expression assays. Here we report that the identity of the amino acids encoded by codons 3 to 5 impact protein yield. This effect is independent of tRNA abundance, translation initiation efficiency, or overall mRNA structure. Single-molecule measurements of translation kinetics revealed pausing of the ribosome and aborted protein synthesis on codons 4 and 5 of distinct amino acid and nucleotide compositions. Finally, introduction of preferred sequence motifs only at specific codon positions improves protein synthesis efficiency for recombinant proteins. Collectively, our data underscore the critical role of early elongation events in translational control of gene expression. Several factors contribute to the efficiency of protein expression. Here the authors show that the identity of amino acids encoded by codons at position 3–5 significantly impact translation efficiency and protein expression levels.
Collapse
Affiliation(s)
- Manasvi Verma
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA
| | - Junhong Choi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, 94305-5126, USA.,Department of Applied Physics, Stanford University, Stanford, CA, 94305-5126, USA.,Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Kyle A Cottrell
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA
| | - Zeno Lavagnino
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA.,Experimental Imaging Center, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Erica N Thomas
- Department of Biology, Washington University, St Louis, MO, 63105, USA
| | - Slavica Pavlovic-Djuranovic
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA
| | - Pawel Szczesny
- Department of Bioinformatics, Institute of Biochemistry and Biophysics Polish Academy of Sciences, Warsaw, Poland
| | - David W Piston
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA
| | - Hani S Zaher
- Department of Biology, Washington University, St Louis, MO, 63105, USA
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, 94305-5126, USA
| | - Sergej Djuranovic
- Department of Cell Biology and Physiology, Washington University School of Medicine, 600 South Euclid Avenue, Campus Box 8228, St. Louis, MO, 63110, USA.
| |
Collapse
|
9
|
Tracking of single tRNAs for translation kinetics measurements in chloramphenicol treated bacteria. Methods 2019; 162-163:23-30. [DOI: 10.1016/j.ymeth.2019.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/01/2019] [Accepted: 02/05/2019] [Indexed: 01/28/2023] Open
|
10
|
Abstract
The ribosome is a major antibiotic target. Many types of inhibitors can stop cells from growing by binding at functional centers of the ribosome and interfering with its ability to synthesize proteins. These antibiotics were usually viewed as general protein synthesis inhibitors, which indiscriminately stop translation at every codon of every mRNA, preventing the ribosome from making any protein. However, at each step of the translation cycle, the ribosome interacts with multiple ligands (mRNAs, tRNA substrates, translation factors, etc.), and as a result, the properties of the translation complex vary from codon to codon and from gene to gene. Therefore, rather than being indiscriminate inhibitors, many ribosomal antibiotics impact protein synthesis in a context-specific manner. This review presents a snapshot of the growing body of evidence that some, and possibly most, ribosome-targeting antibiotics manifest site specificity of action, which is modulated by the nature of the nascent protein, the mRNA, or the tRNAs.
Collapse
Affiliation(s)
- Nora Vázquez-Laslop
- Center for Biomolecular Sciences, University of Illinois, Chicago, Illinois 60607, USA; ,
| | - Alexander S Mankin
- Center for Biomolecular Sciences, University of Illinois, Chicago, Illinois 60607, USA; ,
| |
Collapse
|
11
|
Vázquez-Laslop N, Mankin AS. How Macrolide Antibiotics Work. Trends Biochem Sci 2018; 43:668-684. [PMID: 30054232 PMCID: PMC6108949 DOI: 10.1016/j.tibs.2018.06.011] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/17/2018] [Accepted: 06/29/2018] [Indexed: 01/24/2023]
Abstract
Macrolide antibiotics inhibit protein synthesis by targeting the bacterial ribosome. They bind at the nascent peptide exit tunnel and partially occlude it. Thus, macrolides have been viewed as 'tunnel plugs' that stop the synthesis of every protein. More recent evidence, however, demonstrates that macrolides selectively inhibit the translation of a subset of cellular proteins, and that their action crucially depends on the nascent protein sequence and on the antibiotic structure. Therefore, macrolides emerge as modulators of translation rather than as global inhibitors of protein synthesis. The context-specific action of macrolides is the basis for regulating the expression of resistance genes. Understanding the details of the mechanism of macrolide action may inform rational design of new drugs and unveil important principles of translation regulation.
Collapse
Affiliation(s)
- Nora Vázquez-Laslop
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
| | - Alexander S Mankin
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
| |
Collapse
|
12
|
Choi J, Grosely R, Prabhakar A, Lapointe CP, Wang J, Puglisi JD. How Messenger RNA and Nascent Chain Sequences Regulate Translation Elongation. Annu Rev Biochem 2018; 87:421-449. [PMID: 29925264 PMCID: PMC6594189 DOI: 10.1146/annurev-biochem-060815-014818] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Translation elongation is a highly coordinated, multistep, multifactor process that ensures accurate and efficient addition of amino acids to a growing nascent-peptide chain encoded in the sequence of translated messenger RNA (mRNA). Although translation elongation is heavily regulated by external factors, there is clear evidence that mRNA and nascent-peptide sequences control elongation dynamics, determining both the sequence and structure of synthesized proteins. Advances in methods have driven experiments that revealed the basic mechanisms of elongation as well as the mechanisms of regulation by mRNA and nascent-peptide sequences. In this review, we highlight how mRNA and nascent-peptide elements manipulate the translation machinery to alter the dynamics and pathway of elongation.
Collapse
Affiliation(s)
- Junhong Choi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
- Department of Applied Physics, Stanford University, Stanford, California 94305-4090, USA
| | - Rosslyn Grosely
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
| | - Arjun Prabhakar
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
- Program in Biophysics, Stanford University, Stanford, California 94305, USA
| | - Christopher P Lapointe
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
| | - Jinfan Wang
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305-5126, USA; , , , , ,
| |
Collapse
|
13
|
Abstract
ARE ABC-F genes have been found in numerous pathogen genomes and multi-drug resistance conferring plasmids. Further transmission will challenge the clinical use of many antibiotics. The development of improved ribosome-targeting therapeutics relies on the elucidation of the resistance mechanisms. Characterization of MsrE protein bound to the bacterial ribosome is first of its kind for ARE ABC-F members. Together with biochemical data, it sheds light on the ribosome protection mechanism by domain linker-mediated conformational change and displacement leading to drug release, suggesting a mechanism shared by other ARE ABC-F proteins. These proteins present an intriguing example of structure-function relationship and a medically relevant target of study as they collectively mediate resistance to the majority of antibiotic classes targeting the peptidyl-transferase center region. The ribosome is one of the richest targets for antibiotics. Unfortunately, antibiotic resistance is an urgent issue in clinical practice. Several ATP-binding cassette family proteins confer resistance to ribosome-targeting antibiotics through a yet unknown mechanism. Among them, MsrE has been implicated in macrolide resistance. Here, we report the cryo-EM structure of ATP form MsrE bound to the ribosome. Unlike previously characterized ribosomal protection proteins, MsrE is shown to bind to ribosomal exit site. Our structure reveals that the domain linker forms a unique needle-like arrangement with two crossed helices connected by an extended loop projecting into the peptidyl-transferase center and the nascent peptide exit tunnel, where numerous antibiotics bind. In combination with biochemical assays, our structure provides insight into how MsrE binding leads to conformational changes, which results in the release of the drug. This mechanism appears to be universal for the ABC-F type ribosome protection proteins.
Collapse
|
14
|
Larsen KP, Mathiharan YK, Kappel K, Coey AT, Chen DH, Barrero D, Madigan L, Puglisi JD, Skiniotis G, Puglisi EV. Architecture of an HIV-1 reverse transcriptase initiation complex. Nature 2018; 557:118-122. [PMID: 29695867 PMCID: PMC5934294 DOI: 10.1038/s41586-018-0055-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 03/19/2018] [Indexed: 11/29/2022]
Abstract
Reverse transcription of the HIV-1 RNA genome into double-stranded DNA is a central step in infection1 and a common target of antiretrovirals2. The reaction is catalyzed by viral reverse transcriptase (RT)3,4 that is packaged in an infectious virion along with 2 copies of dimeric viral genomic RNA5 and host tRNALys3, which acts as a primer for initiation of reverse transcription6,7. Upon viral entry, initiation is slow and non-processive compared to elongation8,9. Despite extensive efforts, the structural basis for RT function during initiation has remained a mystery. Here we apply cryo-electron microscopy (cryo-EM) to determine a three-dimensional structure of the HIV-1 RT initiation complex. RT is in an inactive polymerase conformation with open fingers and thumb and with the nucleic acid primer-template complex shifted away from the active site. The primer binding site (PBS) helix formed between tRNALys3 and HIV-1 RNA lies in the cleft of RT and is extended by additional pairing interactions. The 5′ end of the tRNA refolds and stacks on the PBS to create a long helical structure, while the remaining viral RNA forms two helical stems positioned above the RT active site, with a linker that connects these helices to the RNase H region of the PBS. Our results illustrate how RNA structure in the initiation complex alters RT conformation to decrease activity, highlighting a potential target for drug action.
Collapse
Affiliation(s)
- Kevin P Larsen
- Program in Biophysics, Stanford University, Stanford, CA, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yamuna Kalyani Mathiharan
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Kalli Kappel
- Program in Biophysics, Stanford University, Stanford, CA, USA
| | - Aaron T Coey
- Program in Biophysics, Stanford University, Stanford, CA, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Dong-Hua Chen
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Daniel Barrero
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Lauren Madigan
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Georgios Skiniotis
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA.,Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | | |
Collapse
|
15
|
Erythromycin leads to differential protein expression through differences in electrostatic and dispersion interactions with nascent proteins. Sci Rep 2018; 8:6460. [PMID: 29691429 PMCID: PMC5915450 DOI: 10.1038/s41598-018-24344-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 03/23/2018] [Indexed: 11/13/2022] Open
Abstract
The antibiotic activity of erythromycin, which reversibly binds to a site within the bacterial ribosome exit tunnel, against many gram positive microorganisms indicates that it effectively inhibits the production of proteins. Similar to other macrolides, the activity of erythromycin is far from universal, as some peptides can bypass the macrolide-obstructed exit tunnel and become partially or fully synthesized. It is unclear why, at the molecular level, some proteins can be synthesized while others cannot. Here, we use steered molecular dynamics simulations to examine how erythromycin inhibits synthesis of the peptide ErmCL but not the peptide H-NS. By pulling these peptides through the exit tunnel of the E.coli ribosome with and without erythromycin present, we find that erythromycin directly interacts with both nascent peptides, but the force required for ErmCL to bypass erythromycin is greater than that of H-NS. The largest forces arise three to six residues from their N-terminus as they start to bypass Erythromycin. Decomposing the interaction energies between erythromycin and the peptides at this point, we find that there are stronger electrostatic and dispersion interactions with the more C-terminal residues of ErmCL than with H-NS. These results suggest that erythromycin slows or stalls synthesis of ErmCL compared to H-NS due to stronger interactions with particular residue positions along the nascent protein.
Collapse
|
16
|
Jiang Y, Li F, Wu J, Shi Y, Gong Q. Structural insights into substrate selectivity of ribosomal RNA methyltransferase RlmCD. PLoS One 2017; 12:e0185226. [PMID: 28949991 PMCID: PMC5614603 DOI: 10.1371/journal.pone.0185226] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 09/09/2017] [Indexed: 11/22/2022] Open
Abstract
RlmCD has recently been identified as the S-adenosyl methionine (SAM)-dependent methyltransferase responsible for the formation of m5U at U747 and U1939 of 23S ribosomal RNA in Streptococcus pneumoniae. In this research, we determine the high-resolution crystal structures of apo-form RlmCD and its complex with SAH. Using an in-vitro methyltransferase assay, we reveal the crucial residues for its catalytic functions. Furthermore, structural comparison between RlmCD and its structural homologue RumA, which only catalyzes the m5U1939 in Escherichia coli, implicates that a unique long linker in the central domain of RlmCD is the key factor in determining its substrate selectivity. Its significance in the enzyme activity of RlmCD is further confirmed by in-vitro methyltransferase assay.
Collapse
Affiliation(s)
- Yiyang Jiang
- Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Fudong Li
- Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Jihui Wu
- Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Yunyu Shi
- Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Qingguo Gong
- Hefei National Laboratory For Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
- * E-mail:
| |
Collapse
|
17
|
Prabhakar A, Choi J, Wang J, Petrov A, Puglisi JD. Dynamic basis of fidelity and speed in translation: Coordinated multistep mechanisms of elongation and termination. Protein Sci 2017; 26:1352-1362. [PMID: 28480640 DOI: 10.1002/pro.3190] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 05/03/2017] [Indexed: 12/11/2022]
Abstract
As the universal machine that transfers genetic information from RNA to protein, the ribosome synthesizes proteins with remarkably high fidelity and speed. This is a result of the accurate and efficient decoding of mRNA codons via multistep mechanisms during elongation and termination stages of translation. These mechanisms control how the correct sense codon is recognized by a tRNA for peptide elongation, how the next codon is presented to the decoding center without change of frame during translocation, and how the stop codon is discriminated for timely release of the nascent peptide. These processes occur efficiently through coupling of chemical energy expenditure, ligand interactions, and conformational changes. Understanding this coupling in detail required integration of many techniques that were developed in the past two decades. This multidisciplinary approach has revealed the dynamic nature of translational control and uncovered how external cellular factors such as tRNA abundance and mRNA modifications affect the synthesis of the protein product. Insights from these studies will aid synthetic biology and therapeutic approaches to translation.
Collapse
Affiliation(s)
- Arjun Prabhakar
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, 94305.,Program in Biophysics, Stanford University, Stanford, California, 94305
| | - Junhong Choi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, 94305.,Department of Applied Physics, Stanford University, Stanford, California, 94305
| | - Jinfan Wang
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, 94305
| | - Alexey Petrov
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, 94305
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, California, 94305
| |
Collapse
|
18
|
Fyfe C, Grossman TH, Kerstein K, Sutcliffe J. Resistance to Macrolide Antibiotics in Public Health Pathogens. Cold Spring Harb Perspect Med 2016; 6:a025395. [PMID: 27527699 PMCID: PMC5046686 DOI: 10.1101/cshperspect.a025395] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Macrolide resistance mechanisms can be target-based with a change in a 23S ribosomal RNA (rRNA) residue or a mutation in ribosomal protein L4 or L22 affecting the ribosome's interaction with the antibiotic. Alternatively, mono- or dimethylation of A2058 in domain V of the 23S rRNA by an acquired rRNA methyltransferase, the product of an erm (erythromycin ribosome methylation) gene, can interfere with antibiotic binding. Acquired genes encoding efflux pumps, most predominantly mef(A) + msr(D) in pneumococci/streptococci and msr(A/B) in staphylococci, also mediate resistance. Drug-inactivating mechanisms include phosphorylation of the 2'-hydroxyl of the amino sugar found at position C5 by phosphotransferases and hydrolysis of the macrocyclic lactone by esterases. These acquired genes are regulated by either translation or transcription attenuation, largely because cells are less fit when these genes, especially the rRNA methyltransferases, are highly induced or constitutively expressed. The induction of gene expression is cleverly tied to the mechanism of action of macrolides, relying on antibiotic-bound ribosomes stalled at specific sequences of nascent polypeptides to promote transcription or translation of downstream sequences.
Collapse
Affiliation(s)
- Corey Fyfe
- Tetraphase Pharmaceuticals, Watertown, Massachusetts 02472
| | | | - Kathy Kerstein
- Tetraphase Pharmaceuticals, Watertown, Massachusetts 02472
| | | |
Collapse
|
19
|
Auerbach-Nevo T, Baram D, Bashan A, Belousoff M, Breiner E, Davidovich C, Cimicata G, Eyal Z, Halfon Y, Krupkin M, Matzov D, Metz M, Rufayda M, Peretz M, Pick O, Pyetan E, Rozenberg H, Shalev-Benami M, Wekselman I, Zarivach R, Zimmerman E, Assis N, Bloch J, Israeli H, Kalaora R, Lim L, Sade-Falk O, Shapira T, Taha-Salaime L, Tang H, Yonath A. Ribosomal Antibiotics: Contemporary Challenges. Antibiotics (Basel) 2016; 5:antibiotics5030024. [PMID: 27367739 PMCID: PMC5039520 DOI: 10.3390/antibiotics5030024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/07/2016] [Accepted: 06/20/2016] [Indexed: 11/30/2022] Open
Abstract
Most ribosomal antibiotics obstruct distinct ribosomal functions. In selected cases, in addition to paralyzing vital ribosomal tasks, some ribosomal antibiotics are involved in cellular regulation. Owing to the global rapid increase in the appearance of multi-drug resistance in pathogenic bacterial strains, and to the extremely slow progress in developing new antibiotics worldwide, it seems that, in addition to the traditional attempts at improving current antibiotics and the intensive screening for additional natural compounds, this field should undergo substantial conceptual revision. Here, we highlight several contemporary issues, including challenging the common preference of broad-range antibiotics; the marginal attention to alterations in the microbiome population resulting from antibiotics usage, and the insufficient awareness of ecological and environmental aspects of antibiotics usage. We also highlight recent advances in the identification of species-specific structural motifs that may be exploited for the design and the creation of novel, environmental friendly, degradable, antibiotic types, with a better distinction between pathogens and useful bacterial species in the microbiome. Thus, these studies are leading towards the design of “pathogen-specific antibiotics,” in contrast to the current preference of broad range antibiotics, partially because it requires significant efforts in speeding up the discovery of the unique species motifs as well as the clinical pathogen identification.
Collapse
Affiliation(s)
- Tamar Auerbach-Nevo
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - David Baram
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Anat Bashan
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Matthew Belousoff
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Elinor Breiner
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Chen Davidovich
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Giuseppe Cimicata
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Zohar Eyal
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Yehuda Halfon
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Miri Krupkin
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Donna Matzov
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Markus Metz
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Mruwat Rufayda
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Moshe Peretz
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Ophir Pick
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Erez Pyetan
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Haim Rozenberg
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Moran Shalev-Benami
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Itai Wekselman
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Raz Zarivach
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Ella Zimmerman
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Nofar Assis
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Joel Bloch
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Hadar Israeli
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Rinat Kalaora
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Lisha Lim
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Ofir Sade-Falk
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Tal Shapira
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Leena Taha-Salaime
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Hua Tang
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| | - Ada Yonath
- Department of Structural Biology, Weizmann Institute, Rehovot 76100, Israel.
| |
Collapse
|
20
|
The molecular choreography of protein synthesis: translational control, regulation, and pathways. Q Rev Biophys 2016; 49:e11. [PMID: 27658712 DOI: 10.1017/s0033583516000056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Translation of proteins by the ribosome regulates gene expression, with recent results underscoring the importance of translational control. Misregulation of translation underlies many diseases, including cancer and many genetic diseases. Decades of biochemical and structural studies have delineated many of the mechanistic details in prokaryotic translation, and sketched the outlines of eukaryotic translation. However, translation may not proceed linearly through a single mechanistic pathway, but likely involves multiple pathways and branchpoints. The stochastic nature of biological processes would allow different pathways to occur during translation that are biased by the interaction of the ribosome with other translation factors, with many of the steps kinetically controlled. These multiple pathways and branchpoints are potential regulatory nexus, allowing gene expression to be tuned at the translational level. As research focus shifts toward eukaryotic translation, certain themes will be echoed from studies on prokaryotic translation. This review provides a general overview of the dynamic data related to prokaryotic and eukaryotic translation, in particular recent findings with single-molecule methods, complemented by biochemical, kinetic, and structural findings. We will underscore the importance of viewing the process through the viewpoints of regulation, translational control, and heterogeneous pathways.
Collapse
|
21
|
Amino acid sequence repertoire of the bacterial proteome and the occurrence of untranslatable sequences. Proc Natl Acad Sci U S A 2016; 113:7166-70. [PMID: 27307442 DOI: 10.1073/pnas.1606518113] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bioinformatic analysis of Escherichia coli proteomes revealed that all possible amino acid triplet sequences occur at their expected frequencies, with four exceptions. Two of the four underrepresented sequences (URSs) were shown to interfere with translation in vivo and in vitro. Enlarging the URS by a single amino acid resulted in increased translational inhibition. Single-molecule methods revealed stalling of translation at the entrance of the peptide exit tunnel of the ribosome, adjacent to ribosomal nucleotides A2062 and U2585. Interaction with these same ribosomal residues is involved in regulation of translation by longer, naturally occurring protein sequences. The E. coli exit tunnel has evidently evolved to minimize interaction with the exit tunnel and maximize the sequence diversity of the proteome, although allowing some interactions for regulatory purposes. Bioinformatic analysis of the human proteome revealed no underrepresented triplet sequences, possibly reflecting an absence of regulation by interaction with the exit tunnel.
Collapse
|
22
|
Translation regulation via nascent polypeptide-mediated ribosome stalling. Curr Opin Struct Biol 2016; 37:123-33. [DOI: 10.1016/j.sbi.2016.01.008] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/08/2016] [Accepted: 01/12/2016] [Indexed: 11/23/2022]
|
23
|
Coupling of mRNA Structure Rearrangement to Ribosome Movement during Bypassing of Non-coding Regions. Cell 2016; 163:1267-1280. [PMID: 26590426 DOI: 10.1016/j.cell.2015.10.064] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 09/07/2015] [Accepted: 10/21/2015] [Indexed: 01/13/2023]
Abstract
Nearly half of the ribosomes translating a particular bacteriophage T4 mRNA bypass a region of 50 nt, resuming translation 3' of this gap. How this large-scale, specific hop occurs and what determines whether a ribosome bypasses remain unclear. We apply single-molecule fluorescence with zero-mode waveguides to track individual Escherichia coli ribosomes during translation of T4's gene 60 mRNA. Ribosomes that bypass are characterized by a 10- to 20-fold longer pause in a non-canonical rotated state at the take-off codon. During the pause, mRNA secondary structure rearrangements are coupled to ribosome forward movement, facilitated by nascent peptide interactions that disengage the ribosome anticodon-codon interactions for slippage. Close to the landing site, the ribosome then scans mRNA in search of optimal base-pairing interactions. Our results provide a mechanistic and conformational framework for bypassing, highlighting a non-canonical ribosomal state to allow for mRNA structure refolding to drive large-scale ribosome movements.
Collapse
|
24
|
Zhang J, Pan X, Yan K, Sun S, Gao N, Sui SF. Mechanisms of ribosome stalling by SecM at multiple elongation steps. eLife 2015; 4. [PMID: 26670735 PMCID: PMC4737659 DOI: 10.7554/elife.09684] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 09/30/2015] [Indexed: 12/12/2022] Open
Abstract
Regulation of translating ribosomes is a major component of gene expression control network. In Escherichia coli, ribosome stalling by the C-terminal arrest sequence of SecM regulates the SecA-dependent secretion pathway. Previous studies reported many residues of SecM peptide and ribosome exit tunnel are critical for stalling. However, the underlying molecular mechanism is still not clear at the atomic level. Here, we present two cryo-EM structures of the SecM-stalled ribosomes at 3.3–3.7 Å resolution, which reveal two different stalling mechanisms at distinct elongation steps of the translation cycle: one is due to the inactivation of ribosomal peptidyl-transferase center which inhibits peptide bond formation with the incoming prolyl-tRNA; the other is the prolonged residence of the peptidyl-RNA at the hybrid A/P site which inhibits the full-scale tRNA translocation. These results demonstrate an elegant control of translation cycle by regulatory peptides through a continuous, dynamic reshaping of the functional center of the ribosome. DOI:http://dx.doi.org/10.7554/eLife.09684.001 Many genes code for proteins that carry out essential tasks. The instructions in a gene are first copied into a messenger RNA (mRNA), and a molecular machine known as a ribosome reads the copied instructions in groups of three letters at a time (called codons). The ribosome translates the order of the codons into a sequence of amino acids; each amino acid is carried into the ribosome by a transfer RNA (tRNA) molecule. As it translates, the ribosome joins each new amino acid to the one before it, like the links in a chain. Finally, the newly built protein chain passes through a tunnel to exit the ribosome. Ribosomes do not build all proteins at a constant rate; there are many examples of proteins that stall when they are in the ribosome exit tunnel. It is thought that this stalling is an important way for cells to control the expression of proteins. SecM is a bacterial protein that stalls while it is being made. Previous research has shown that a sequence of amino acids in SecM (called the arrest sequence) interacts with components of the ribosome tunnel. This interaction leads to stalling, and regulates the translation of another important bacterial protein (called SecA) that is encoded downstream on the same mRNA as SecM. If SecM-induced stalling takes place, the translation of SecA actually increases. Nevertheless, it remains poorly understood how SecM stalls in the ribosome. Zhang et al. have now solved the structures of SecM proteins stalled inside ribosomes using a method called cryo-electron microscopy. This approach identified two different states of SecM present in the ribosome, which corresponded to two different stalling mechanisms. The addition of an amino acid to a growing protein occurs in stages. First, the tRNA that carries the amino acid to the ribosome and bind to it in a region known as the A-site. After this, the tRNA moves to the P-site where the attached amino acid is incorporated into the elongating protein chain. Zhang et al. observed that the arrest sequence of SecM and the ribosome tunnel interact extensively. These interactions are strong and alter the configuration of both the A-site and P-site of the ribosome. This has two major consequences for translation. First, the tRNA cannot be stably accommodated in the A-site and secondly, its passage to the P-site is slowed down. Both these mechanisms contribute to stalling. This study provides a detailed analysis of how the ribosome can adjust to control translation. It also highlights that codon-specific control of translation constitutes an important component of how gene expression is regulated. DOI:http://dx.doi.org/10.7554/eLife.09684.002
Collapse
Affiliation(s)
- Jun Zhang
- State Key Laboratory of Membrane Biology, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Xijiang Pan
- State Key Laboratory of Membrane Biology, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Kaige Yan
- Ministry of Education Key Laboratory of Protein Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shan Sun
- State Key Laboratory of Membrane Biology, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Ning Gao
- Ministry of Education Key Laboratory of Protein Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Sen-Fang Sui
- State Key Laboratory of Membrane Biology, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| |
Collapse
|
25
|
Probing the Translation Dynamics of Ribosomes Using Zero-Mode Waveguides. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 139:1-43. [PMID: 26970189 DOI: 10.1016/bs.pmbts.2015.10.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In order to coordinate the complex biochemical and structural feat of converting triple-nucleotide codons into their corresponding amino acids, the ribosome must physically manipulate numerous macromolecules including the mRNA, tRNAs, and numerous translation factors. The ribosome choreographs binding, dissociation, physical movements, and structural rearrangements so that they synergistically harness the energy from biochemical processes, including numerous GTP hydrolysis steps and peptide bond formation. Due to the dynamic and complex nature of translation, the large cast of ligands involved, and the large number of possible configurations, tracking the global time evolution or dynamics of the ribosome complex in translation has proven to be challenging for bulk methods. Conventional single-molecule fluorescence experiments on the other hand require low concentrations of fluorescent ligands to reduce background noise. The significantly reduced bimolecular association rates under those conditions limit the number of steps that can be observed within the time window available to a fluorophore. The advent of zero-mode waveguide (ZMW) technology has allowed the study of translation at near-physiological concentrations of labeled ligands, moving single-molecule fluorescence microscopy beyond focused model systems into studying the global dynamics of translation in realistic setups. This chapter reviews the recent works using the ZMW technology to dissect the mechanism of translation initiation and elongation in prokaryotes, including complex processes such as translational stalling and frameshifting. Given the success of the technology, similarly complex biological processes could be studied in near-physiological conditions with the controllability of conventional in vitro experiments.
Collapse
|
26
|
Nilsson OB, Hedman R, Marino J, Wickles S, Bischoff L, Johansson M, Müller-Lucks A, Trovato F, Puglisi JD, O'Brien EP, Beckmann R, von Heijne G. Cotranslational Protein Folding inside the Ribosome Exit Tunnel. Cell Rep 2015; 12:1533-40. [PMID: 26321634 PMCID: PMC4571824 DOI: 10.1016/j.celrep.2015.07.065] [Citation(s) in RCA: 183] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/17/2015] [Accepted: 07/29/2015] [Indexed: 12/25/2022] Open
Abstract
At what point during translation do proteins fold? It is well established that proteins can fold cotranslationally outside the ribosome exit tunnel, whereas studies of folding inside the exit tunnel have so far detected only the formation of helical secondary structure and collapsed or partially structured folding intermediates. Here, using a combination of cotranslational nascent chain force measurements, inter-subunit fluorescence resonance energy transfer studies on single translating ribosomes, molecular dynamics simulations, and cryoelectron microscopy, we show that a small zinc-finger domain protein can fold deep inside the vestibule of the ribosome exit tunnel. Thus, for small protein domains, the ribosome itself can provide the kind of sheltered folding environment that chaperones provide for larger proteins. Cotranslational folding is studied by arrest-peptide-mediated force measurements Single-molecule measurements show that a pulling force prevents ribosome stalling A ribosome-tethered zinc-finger domain is visualized by cryo-EM (electron microscopy) The zinc-finger domain is shown to fold deep inside the ribosome exit tunnel
Collapse
Affiliation(s)
- Ola B Nilsson
- Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Rickard Hedman
- Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Jacopo Marino
- Gene Center and Center for Integrated Protein Science Munich, CiPS-M, Feodor-Lynen-Strasse 25, University of Munich, 81377 Munich, Germany
| | - Stephan Wickles
- Gene Center and Center for Integrated Protein Science Munich, CiPS-M, Feodor-Lynen-Strasse 25, University of Munich, 81377 Munich, Germany
| | - Lukas Bischoff
- Gene Center and Center for Integrated Protein Science Munich, CiPS-M, Feodor-Lynen-Strasse 25, University of Munich, 81377 Munich, Germany
| | - Magnus Johansson
- Department of Cell and Molecular Biology, Biomedical Center, Uppsala University, Box 596, 751 24 Uppsala, Sweden
| | - Annika Müller-Lucks
- Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, 106 91 Stockholm, Sweden
| | - Fabio Trovato
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305-5126, USA; Stanford Magnetic Resonance Laboratory, Stanford University School of Medicine, Stanford, CA 94305-5126, USA
| | - Edward P O'Brien
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA
| | - Roland Beckmann
- Gene Center and Center for Integrated Protein Science Munich, CiPS-M, Feodor-Lynen-Strasse 25, University of Munich, 81377 Munich, Germany
| | - Gunnar von Heijne
- Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, 106 91 Stockholm, Sweden; Science for Life Laboratory, Stockholm University, Box 1031, 171 21 Solna, Sweden.
| |
Collapse
|
27
|
Krokidis M, Bougas A, Stavropoulou M, Kalpaxis D, Dinos GP. The slow dissociation rate of K-1602 contributes to the enhanced inhibitory activity of this novel alkyl-aryl-bearing fluoroketolide. J Enzyme Inhib Med Chem 2015; 31:276-82. [PMID: 25807301 DOI: 10.3109/14756366.2015.1018246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ketolides belong to the latest generation of macrolides and are not only effective against macrolide susceptible bacterial strains but also against some macrolide resistant strains. Here we present data providing insights into the mechanism of action of K-1602, a novel alkyl-aryl-bearing fluoroketolide. According to our data, the K-1602 interacts with the ribosome as a one-step slow binding inhibitor, displaying an association rate constant equal to 0.28 × 10(4) M(-1) s(-1) and a dissociation rate constant equal to 0.0025 min(-1). Both constants contribute to produce an overall inhibition constant Ki equal to 1.49 × 10(-8) M, which correlates very well with the superior activity of this compound when compared with many other ketolides or fluoroketolides.
Collapse
Affiliation(s)
- Marios Krokidis
- a Department of Pharmacology , Medical School, University of Athens , Athens , Greece
| | - Anthony Bougas
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
| | - Maria Stavropoulou
- c Department of Chemistry , Technical University of Munich , Munich , Germany
| | - Dimitrios Kalpaxis
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
| | - George P Dinos
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
| |
Collapse
|
28
|
Noriega TR, Chen J, Walter P, Puglisi JD. Real-time observation of signal recognition particle binding to actively translating ribosomes. eLife 2014; 3. [PMID: 25358118 PMCID: PMC4213662 DOI: 10.7554/elife.04418] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/09/2014] [Indexed: 12/15/2022] Open
Abstract
The signal recognition particle (SRP) directs translating ribosome-nascent chain complexes (RNCs) that display a signal sequence to protein translocation channels in target membranes. All previous work on the initial step of the targeting reaction, when SRP binds to RNCs, used stalled and non-translating RNCs. This meant that an important dimension of the co-translational process remained unstudied. We apply single-molecule fluorescence measurements to observe directly and in real-time E. coli SRP binding to actively translating RNCs. We show at physiologically relevant SRP concentrations that SRP-RNC association and dissociation rates depend on nascent chain length and the exposure of a functional signal sequence outside the ribosome. Our results resolve a long-standing question: how can a limited, sub-stoichiometric pool of cellular SRP effectively distinguish RNCs displaying a signal sequence from those that are not? The answer is strikingly simple: as originally proposed, SRP only stably engages translating RNCs exposing a functional signal sequence. DOI:http://dx.doi.org/10.7554/eLife.04418.001 Genes contain the instructions needed to make proteins from smaller building blocks called amino acids. These instructions are first transcribed to produce molecules of messenger RNA, which are then translated by a ribosome. This ‘molecular machine’ translates the instructions in the messenger RNA into the sequence of amino acids needed to make the protein. For some proteins to carry out their role, they need to be delivered to the outside of the cell, or inserted into one of the cell's membranes. As they are being built, these proteins are identified by a so-called ‘signal recognition particle’, which is often called an SRP for short. The SRP attaches to the new protein when it is still joined to the ribosome, and pulls the protein-ribosome complex to an opening in the target membrane. The new protein chain then enters this opening and either passes through to the other side of the membrane, or ends up embedded within it. To date, most studies that have investigated this process have involved scientists stalling the building of the new protein to see how SRP interacts with inactivated protein-ribosome complexes. Unfortunately, this means that some of the details of what happens during this process have likely been missed. Now, Noriega et al. have addressed this problem by developing a method to watch, in real-time, a single active protein-ribosome complex interacting with individual SRPs. This was achieved by attaching fluorescent molecules to SRP and protein-ribosome complexes purified from the bacterium E. coli. The distance between the two fluorescent molecules was then tracked over time. This revealed that the SRP typically binds to the protein-ribosome complex after 40–55 amino acids have been built into the protein. At this point, a so-called ‘signal sequence’ of amino acids has emerged from the complex and can be recognized by the SRP. Earlier studies had suggested that signal sequences might tell the SRP when to bind, but this had not been demonstrated in experiments using active protein-ribosome complexes. The strategy of using fluorescent molecules to follow single molecules undergoing this process in real-time could now be used by other scientists to re-examine and determine new properties of the protein-ribosome complex in action. DOI:http://dx.doi.org/10.7554/eLife.04418.002
Collapse
Affiliation(s)
- Thomas R Noriega
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Jin Chen
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| | - Peter Walter
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Joseph D Puglisi
- Department of Structural Biology, Stanford University School of Medicine, Stanford, United States
| |
Collapse
|
29
|
Rudorf S, Thommen M, Rodnina MV, Lipowsky R. Deducing the kinetics of protein synthesis in vivo from the transition rates measured in vitro. PLoS Comput Biol 2014; 10:e1003909. [PMID: 25358034 PMCID: PMC4214572 DOI: 10.1371/journal.pcbi.1003909] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 09/14/2014] [Indexed: 02/02/2023] Open
Abstract
The molecular machinery of life relies on complex multistep processes that involve numerous individual transitions, such as molecular association and dissociation steps, chemical reactions, and mechanical movements. The corresponding transition rates can be typically measured in vitro but not in vivo. Here, we develop a general method to deduce the in-vivo rates from their in-vitro values. The method has two basic components. First, we introduce the kinetic distance, a new concept by which we can quantitatively compare the kinetics of a multistep process in different environments. The kinetic distance depends logarithmically on the transition rates and can be interpreted in terms of the underlying free energy barriers. Second, we minimize the kinetic distance between the in-vitro and the in-vivo process, imposing the constraint that the deduced rates reproduce a known global property such as the overall in-vivo speed. In order to demonstrate the predictive power of our method, we apply it to protein synthesis by ribosomes, a key process of gene expression. We describe the latter process by a codon-specific Markov model with three reaction pathways, corresponding to the initial binding of cognate, near-cognate, and non-cognate tRNA, for which we determine all individual transition rates in vitro. We then predict the in-vivo rates by the constrained minimization procedure and validate these rates by three independent sets of in-vivo data, obtained for codon-dependent translation speeds, codon-specific translation dynamics, and missense error frequencies. In all cases, we find good agreement between theory and experiment without adjusting any fit parameter. The deduced in-vivo rates lead to smaller error frequencies than the known in-vitro rates, primarily by an improved initial selection of tRNA. The method introduced here is relatively simple from a computational point of view and can be applied to any biomolecular process, for which we have detailed information about the in-vitro kinetics. The proverb ‘life is motion’ also applies to the molecular scale. Indeed, if we looked into any living cell with molecular resolution, we would observe a large variety of highly dynamic processes. One particularly striking aspect of these dynamics is that all macromolecules within the cell are continuously synthesized, modified, and degraded by complex biomolecular machines. These ‘nanorobots’ follow intricate reaction pathways that form networks of molecular transitions or transformation steps. Each of these steps is stochastic and takes, on average, a certain amount of time. A fundamentally important question is how these individual step times or the corresponding transition rates determine the overall speed of the process in the cell. This question is difficult to answer, however, because the step times can only be measured in vitro but not in vivo. Here, we develop a general computational method by which one can deduce the individual step times in vivo from their in-vitro values. In order to demonstrate the predictive power of our method, we apply it to protein synthesis by ribosomes, a key process of gene expression, and validate the deduced step times by three independent sets of in-vivo data.
Collapse
Affiliation(s)
- Sophia Rudorf
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| | - Michael Thommen
- Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Marina V Rodnina
- Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Reinhard Lipowsky
- Theory and Bio-Systems, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany
| |
Collapse
|
30
|
Arenz S, Meydan S, Starosta AL, Berninghausen O, Beckmann R, Vázquez-Laslop N, Wilson DN. Drug sensing by the ribosome induces translational arrest via active site perturbation. Mol Cell 2014; 56:446-452. [PMID: 25306253 DOI: 10.1016/j.molcel.2014.09.014] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/08/2014] [Accepted: 09/11/2014] [Indexed: 10/24/2022]
Abstract
During protein synthesis, nascent polypeptide chains within the ribosomal tunnel can act in cis to induce ribosome stalling and regulate expression of downstream genes. The Staphylococcus aureus ErmCL leader peptide induces stalling in the presence of clinically important macrolide antibiotics, such as erythromycin, leading to the induction of the downstream macrolide resistance methyltransferase ErmC. Here, we present a cryo-electron microscopy (EM) structure of the erythromycin-dependent ErmCL-stalled ribosome at 3.9 Å resolution. The structure reveals how the ErmCL nascent chain directly senses the presence of the tunnel-bound drug and thereby induces allosteric conformational rearrangements at the peptidyltransferase center (PTC) of the ribosome. ErmCL-induced perturbations of the PTC prevent stable binding and accommodation of the aminoacyl-tRNA at the A-site, leading to inhibition of peptide bond formation and translation arrest.
Collapse
Affiliation(s)
- Stefan Arenz
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany
| | - Sezen Meydan
- Center for Pharmaceutical Biotechnology, University of Illinois, Chicago, Chicago, IL 60607, USA
| | - Agata L Starosta
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany
| | - Otto Berninghausen
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany
| | - Roland Beckmann
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany; Center for integrated Protein Science Munich (CiPSM), University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany
| | - Nora Vázquez-Laslop
- Center for Pharmaceutical Biotechnology, University of Illinois, Chicago, Chicago, IL 60607, USA
| | - Daniel N Wilson
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany; Center for integrated Protein Science Munich (CiPSM), University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany.
| |
Collapse
|
31
|
The dynamics of SecM-induced translational stalling. Cell Rep 2014; 7:1521-1533. [PMID: 24836001 DOI: 10.1016/j.celrep.2014.04.033] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 03/27/2014] [Accepted: 04/17/2014] [Indexed: 02/01/2023] Open
Abstract
SecM is an E. coli secretion monitor capable of stalling translation on the prokaryotic ribosome without cofactors. Biochemical and structural studies have demonstrated that the SecM nascent chain interacts with the 50S subunit exit tunnel to inhibit peptide bond formation. However, the timescales and pathways of stalling on an mRNA remain undefined. To provide a dynamic mechanism for stalling, we directly tracked the dynamics of elongation on ribosomes translating the SecM stall sequence (FSTPVWISQAQGIRAGP) using single-molecule fluorescence techniques. Within 1 min, three peptide-ribosome interactions work cooperatively over the last five codons of the SecM sequence, leading to severely impaired elongation rates beginning from the terminal proline and lasting four codons. Our results suggest that stalling is tightly linked to the dynamics of elongation and underscore the roles that the exit tunnel and nascent chain play in controlling fundamental steps in translation.
Collapse
|