1
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Badonyi M, Marsh JA. Hallmarks and evolutionary drivers of cotranslational protein complex assembly. FEBS J 2024; 291:3557-3567. [PMID: 37202910 DOI: 10.1111/febs.16869] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 05/20/2023]
Abstract
Recent discoveries have highlighted the prevalence of cotranslational assembly in proteomes, revealing a range of mechanisms that enables the assembly of protein complex subunits on the ribosome. Structural analyses have uncovered emergent properties that may inherently control whether a subunit undergoes cotranslational assembly. However, the evolutionary paths that have yielded such complexes over an extended timescale remain largely unclear. In this review, we reflect on historical experiments that contributed to the field, including breakthroughs that have made possible the proteome-wide detection of cotranslational assembly, and the technical challenges yet to be overcome. We introduce a simple framework that encapsulates the hallmarks of cotranslational assembly and discuss how results from new experiments are shaping our view of the mechanistic, structural and evolutionary factors driving the phenomenon.
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Affiliation(s)
- Mihaly Badonyi
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, UK
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, UK
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2
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Zhao J, Song W, Huang Z, Yuan X, Huang Y, Hou Y, Liu K, Jin P, Hu SQ. "Top-down" overexpression optimization of butelase-1 in Escherichia coli and its application in anti-tumor peptides. Int J Biol Macromol 2024; 276:133933. [PMID: 39025194 DOI: 10.1016/j.ijbiomac.2024.133933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 07/14/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Butelase-1, the fastest known Asn/Asp-specific peptide ligase capable of catalyzing peptide ligation and cyclization, holds promising application prospects in the fields of food and biology. However, limited research exists on its recombinant expression and potential applications in peptide drugs. In this study, the activity of recombinantly-produced butelase-1 was enhanced by co-expressing it with a molecular chaperone in the SHuffle T7 strain. By introducing single or multiple synonymous rare codons at the beginning of the coding regions of beta-strand or alpha-helix, in combination with ribosomal binding site engineering, the activity of butelase-1 could be further improved. Consequently, the butelase-1 with a specific activity of 386.93 U/mg and a catalytic efficiency of 11,048 M-1 s-1 was successfully prepared in E. coli, resulting in a total activity of 8183.54 U/L and a yield of about 100 mg/L. This optimized butelase-1 was then used to efficiently cyclize the redesigned anti-cancer peptide lunasin, leading to enhanced bioavailability and anti-cancer effects. Overall, this study not only provided valuable biotechnology strategies for improving the recombinant expression of butelase-1 but also demonstrated a successful application for enhancing the biological efficacy of anti-cancer peptides.
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Affiliation(s)
- Jinsong Zhao
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; College of Agricultural and Food Sciences, Zhejiang A & F University, Hangzhou 311300, China
| | - Wen Song
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Zhiqiang Huang
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Xin Yuan
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Yanbo Huang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, Guangdong 510640, China
| | - Yi Hou
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, Guangdong 510640, China
| | - Kun Liu
- Experimental Education/Administration Center, National Demonstration Center for Experimental Education of Basic Medical Sciences, Key Laboratory of Functional Proteomics of Guangdong Province, Department of Cell Biology, School of Basic Medical Sciences Southern Medical University, Guangzhou 510515, China
| | - Peng Jin
- College of Agricultural and Food Sciences, Zhejiang A & F University, Hangzhou 311300, China
| | - Song-Qing Hu
- Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
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3
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Herling TW, Cassaignau AME, Wentink AS, Peter QAE, Kumar PC, Kartanas T, Schneider MM, Cabrita LD, Christodoulou J, Knowles TPJ. Thermodynamic profiles for cotranslational trigger factor substrate recognition. SCIENCE ADVANCES 2024; 10:eadn4824. [PMID: 38985872 PMCID: PMC11235164 DOI: 10.1126/sciadv.adn4824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 06/04/2024] [Indexed: 07/12/2024]
Abstract
Molecular chaperones are central to the maintenance of proteostasis in living cells. A key member of this protein family is trigger factor (TF), which acts throughout the protein life cycle and has a ubiquitous role as the first chaperone encountered by proteins during synthesis. However, our understanding of how TF achieves favorable interactions with such a diverse substrate base remains limited. Here, we use microfluidics to reveal the thermodynamic determinants of this process. We find that TF binding to empty 70S ribosomes is enthalpy-driven, with micromolar affinity, while nanomolar affinity is achieved through a favorable entropic contribution for both intrinsically disordered and folding-competent nascent chains. These findings suggest a general mechanism for cotranslational TF function, which relies on occupation of the exposed TF-substrate binding groove rather than specific complementarity between chaperone and nascent chain. These insights add to our wider understanding of how proteins can achieve broad substrate specificity.
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Affiliation(s)
- Therese W. Herling
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Anaïs M. E. Cassaignau
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1 6BT, UK
| | - Anne S. Wentink
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1 6BT, UK
| | - Quentin A. E. Peter
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Pavan C. Kumar
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Tadas Kartanas
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Matthias M. Schneider
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Lisa D. Cabrita
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1 6BT, UK
| | - John Christodoulou
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, London WC1 6BT, UK
| | - Tuomas P. J. Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
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4
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Roeselová A, Maslen SL, Shivakumaraswamy S, Pellowe GA, Howell S, Joshi D, Redmond J, Kjær S, Skehel JM, Balchin D. Mechanism of chaperone coordination during cotranslational protein folding in bacteria. Mol Cell 2024; 84:2455-2471.e8. [PMID: 38908370 DOI: 10.1016/j.molcel.2024.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/12/2024] [Accepted: 06/01/2024] [Indexed: 06/24/2024]
Abstract
Protein folding is assisted by molecular chaperones that bind nascent polypeptides during mRNA translation. Several structurally distinct classes of chaperones promote de novo folding, suggesting that their activities are coordinated at the ribosome. We used biochemical reconstitution and structural proteomics to explore the molecular basis for cotranslational chaperone action in bacteria. We found that chaperone binding is disfavored close to the ribosome, allowing folding to precede chaperone recruitment. Trigger factor recognizes compact folding intermediates that expose an extensive unfolded surface, and dictates DnaJ access to nascent chains. DnaJ uses a large surface to bind structurally diverse intermediates and recruits DnaK to sequence-diverse solvent-accessible sites. Neither Trigger factor, DnaJ, nor DnaK destabilize cotranslational folding intermediates. Instead, the chaperones collaborate to protect incipient structure in the nascent polypeptide well beyond the ribosome exit tunnel. Our findings show how the chaperone network selects and modulates cotranslational folding intermediates.
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Affiliation(s)
- Alžběta Roeselová
- Protein Biogenesis Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Sarah L Maslen
- Proteomics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | | | - Grant A Pellowe
- Protein Biogenesis Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Steven Howell
- Proteomics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Dhira Joshi
- Chemical Biology Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Joanna Redmond
- Chemical Biology Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - J Mark Skehel
- Proteomics Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - David Balchin
- Protein Biogenesis Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
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5
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Wales TE, Pajak A, Roeselová A, Shivakumaraswamy S, Howell S, Kjær S, Hartl FU, Engen JR, Balchin D. Resolving chaperone-assisted protein folding on the ribosome at the peptide level. Nat Struct Mol Biol 2024:10.1038/s41594-024-01355-x. [PMID: 38987455 DOI: 10.1038/s41594-024-01355-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 06/17/2024] [Indexed: 07/12/2024]
Abstract
Protein folding in vivo begins during synthesis on the ribosome and is modulated by molecular chaperones that engage the nascent polypeptide. How these features of protein biogenesis influence the maturation pathway of nascent proteins is incompletely understood. Here, we use hydrogen-deuterium exchange mass spectrometry to define, at peptide resolution, the cotranslational chaperone-assisted folding pathway of Escherichia coli dihydrofolate reductase. The nascent polypeptide folds along an unanticipated pathway through structured intermediates not populated during refolding from denaturant. Association with the ribosome allows these intermediates to form, as otherwise destabilizing carboxy-terminal sequences remain confined in the ribosome exit tunnel. Trigger factor binds partially folded states without disrupting their structure, and the nascent chain is poised to complete folding immediately upon emergence of the C terminus from the exit tunnel. By mapping interactions between the nascent chain and ribosomal proteins, we trace the path of the emerging polypeptide during synthesis. Our work reveals new mechanisms by which cellular factors shape the conformational search for the native state.
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Affiliation(s)
- Thomas E Wales
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, USA
| | - Aleksandra Pajak
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK
| | - Alžběta Roeselová
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK
| | | | - Steven Howell
- Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - John R Engen
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA, USA.
| | - David Balchin
- Protein Biogenesis Laboratory, The Francis Crick Institute, London, UK.
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6
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Nyerges A, Chiappino-Pepe A, Budnik B, Baas-Thomas M, Flynn R, Yan S, Ostrov N, Liu M, Wang M, Zheng Q, Hu F, Chen K, Rudolph A, Chen D, Ahn J, Spencer O, Ayalavarapu V, Tarver A, Harmon-Smith M, Hamilton M, Blaby I, Yoshikuni Y, Hajian B, Jin A, Kintses B, Szamel M, Seregi V, Shen Y, Li Z, Church GM. Synthetic genomes unveil the effects of synonymous recoding. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.16.599206. [PMID: 38915524 PMCID: PMC11195188 DOI: 10.1101/2024.06.16.599206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Engineering the genetic code of an organism provides the basis for (i) making any organism safely resistant to natural viruses and (ii) preventing genetic information flow into and out of genetically modified organisms while (iii) allowing the biosynthesis of genetically encoded unnatural polymers1-4. Achieving these three goals requires the reassignment of multiple of the 64 codons nature uses to encode proteins. However, synonymous codon replacement-recoding-is frequently lethal, and how recoding impacts fitness remains poorly explored. Here, we explore these effects using whole-genome synthesis, multiplexed directed evolution, and genome-transcriptome-translatome-proteome co-profiling on multiple recoded genomes. Using this information, we assemble a synthetic Escherichia coli genome in seven sections using only 57 codons to encode proteins. By discovering the rules responsible for the lethality of synonymous recoding and developing a data-driven multi-omics-based genome construction workflow that troubleshoots synthetic genomes, we overcome the lethal effects of 62,007 synonymous codon swaps and 11,108 additional genomic edits. We show that synonymous recoding induces transcriptional noise including new antisense RNAs, leading to drastic transcriptome and proteome perturbation. As the elimination of select codons from an organism's genetic code results in the widespread appearance of cryptic promoters, we show that synonymous codon choice may naturally evolve to minimize transcriptional noise. Our work provides the first genome-scale description of how synonymous codon changes influence organismal fitness and paves the way for the construction of functional genomes that provide genetic firewalls from natural ecosystems and safely produce biopolymers, drugs, and enzymes with an expanded chemistry.
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Affiliation(s)
- Akos Nyerges
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - Bogdan Budnik
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | | | - Regan Flynn
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Shirui Yan
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- BGI Research, Shenzhen 518083, China
| | - Nili Ostrov
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Min Liu
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | | | | | | | | | - Alexandra Rudolph
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Dawn Chen
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Jenny Ahn
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Owen Spencer
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - Angela Tarver
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Miranda Harmon-Smith
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Matthew Hamilton
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ian Blaby
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yasuo Yoshikuni
- DOE Joint Genome Institute (JGI), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Behnoush Hajian
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Adeline Jin
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | - Balint Kintses
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Monika Szamel
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Viktoria Seregi
- Institute of Biochemistry, HUN-REN Biological Research Centre, Szeged, 6726, Hungary
| | - Yue Shen
- BGI Research, Shenzhen 518083, China
- BGI Research, Changzhou 213299, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, BGI Research, Shenzhen 518083, China
| | - Zilong Li
- GenScript USA Inc., Piscataway, NJ 08854, USA
| | - George M. Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
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7
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Masse MM, Guzman-Luna V, Varela AE, Mahfuza Shapla U, Hutchinson RB, Srivastava A, Wei W, Fuchs AM, Cavagnero S. Nascent chains derived from a foldable protein sequence interact with specific ribosomal surface sites near the exit tunnel. Sci Rep 2024; 14:12324. [PMID: 38811604 PMCID: PMC11137106 DOI: 10.1038/s41598-024-61274-1] [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: 03/25/2023] [Accepted: 05/03/2024] [Indexed: 05/31/2024] Open
Abstract
In order to become bioactive, proteins must be translated and protected from aggregation during biosynthesis. The ribosome and molecular chaperones play a key role in this process. Ribosome-bound nascent chains (RNCs) of intrinsically disordered proteins and RNCs bearing a signal/arrest sequence are known to interact with ribosomal proteins. However, in the case of RNCs bearing foldable protein sequences, not much information is available on these interactions. Here, via a combination of chemical crosslinking and time-resolved fluorescence-anisotropy, we find that nascent chains of the foldable globin apoHmp1-140 interact with ribosomal protein L23 and have a freely-tumbling non-interacting N-terminal compact region comprising 63-94 residues. Longer RNCs (apoHmp1-189) also interact with an additional yet unidentified ribosomal protein, as well as with chaperones. Surprisingly, the apparent strength of RNC/r-protein interactions does not depend on nascent-chain sequence. Overall, foldable nascent chains establish and expand interactions with selected ribosomal proteins and chaperones, as they get longer. These data are significant because they reveal the interplay between independent conformational sampling and nascent-protein interactions with the ribosomal surface.
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Affiliation(s)
- Meranda M Masse
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Valeria Guzman-Luna
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Angela E Varela
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Ummay Mahfuza Shapla
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Rachel B Hutchinson
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Food Science, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Aniruddha Srivastava
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- McGaw Medical Center, Northwestern University, Chicago, IL, 60611, USA
| | - Wanting Wei
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- AIDS Vaccine Research Laboratory, University of Wisconsin-Madison, Madison, WI, 53711, USA
| | - Andrew M Fuchs
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Silvia Cavagnero
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
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8
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Wu W, Pang CNI, Mediati DG, Tree JJ. The functional small RNA interactome reveals targets for the vancomycin-responsive sRNA RsaOI in vancomycin-tolerant Staphylococcus aureus. mSystems 2024; 9:e0097123. [PMID: 38534138 PMCID: PMC11019875 DOI: 10.1128/msystems.00971-23] [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: 09/11/2023] [Accepted: 03/11/2024] [Indexed: 03/28/2024] Open
Abstract
Small RNAs have been found to control a broad range of bacterial phenotypes including tolerance to antibiotics. Vancomycin tolerance in multidrug resistance Staphylococcus aureus is correlated with dysregulation of small RNAs although their contribution to antibiotic tolerance is poorly understood. RNA-RNA interactome profiling techniques are expanding our understanding of sRNA-mRNA interactions in bacteria; however, determining the function of these interactions for hundreds of sRNA-mRNA pairs is a major challenge. At steady-state, protein and mRNA abundances are often highly correlated and lower than expected protein abundance may indicate translational repression of an mRNA. To identify sRNA-mRNA interactions that regulate mRNA translation, we examined the correlation between gene transcript abundance, ribosome occupancy, and protein levels. We used the machine learning technique self-organizing maps (SOMs) to cluster genes with similar transcription and translation patterns and identified a cluster of mRNAs that appeared to be post-transcriptionally repressed. By integrating our clustering with sRNA-mRNA interactome data generated in vancomycin-tolerant S. aureus by RNase III-CLASH, we identified sRNAs that may be mediating translational repression. We have confirmed sRNA-dependant post-transcriptional repression of several mRNAs in this cluster. Two of these interactions are mediated by RsaOI, a sRNA that is highly upregulated by vancomycin. We demonstrate the regulation of HPr and the cell-wall autolysin Atl. These findings suggest that RsaOI coordinates carbon metabolism and cell wall turnover during vancomycin treatment. IMPORTANCE The emergence of multidrug-resistant Staphylococcus aureus (MRSA) is a major public health concern. Current treatment is dependent on the efficacy of last-line antibiotics like vancomycin. The most common cause of vancomycin treatment failure is strains with intermediate resistance or tolerance that arise through the acqusition of a diverse repertoire of point mutations. These strains have been shown to altered small RNA (sRNA) expression in response to antibiotic treatment. Here, we have used a technique termed RNase III-CLASH to capture sRNA interactions with their target mRNAs. To understand the function of these interactions, we have looked at RNA and protein abundance for mRNAs targeted by sRNAs. Messenger RNA and protein levels are generally well correlated and we use deviations from this correlation to infer post-transcriptional regulation and the function of individual sRNA-mRNA interactions. Using this approach we identify mRNA targets of the vancomycin-induced sRNA, RsaOI, that are repressed at the translational level. We find that RsaOI represses the cell wall autolysis Atl and carbon transporter HPr suggestion a link between vancomycin treatment and suppression of cell wall turnover and carbon metabolism.
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Affiliation(s)
- Winton Wu
- School of Biotechnology and Biomolecular Sciences, Sydney, New South Wales, Australia
| | | | - Daniel G. Mediati
- School of Biotechnology and Biomolecular Sciences, Sydney, New South Wales, Australia
| | - Jai Justin Tree
- School of Biotechnology and Biomolecular Sciences, Sydney, New South Wales, Australia
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9
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McGrath KM, Russell SJ, Fer E, Garmendia E, Hosgel A, Baltrus DA, Kaçar B. Fitness benefits of a synonymous substitution in an ancient EF-Tu gene depend on the genetic background. J Bacteriol 2024; 206:e0032923. [PMID: 38289064 PMCID: PMC10882980 DOI: 10.1128/jb.00329-23] [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: 10/02/2023] [Accepted: 01/05/2024] [Indexed: 02/13/2024] Open
Abstract
Synonymous mutations are changes to DNA sequence, which occur within translated genes but which do not affect the protein sequence. Although often referred to as silent mutations, evidence suggests that synonymous mutations can affect gene expression, mRNA stability, and even translation efficiency. A collection of both experimental and bioinformatic data has shown that synonymous mutations can impact cell phenotype, yet less is known about the molecular mechanisms and potential of beneficial or adaptive effects of such changes within evolved populations. Here, we report a beneficial synonymous mutation acquired via experimental evolution in an essential gene variant encoding the translation elongation factor protein EF-Tu. We demonstrate that this particular synonymous mutation increases EF-Tu mRNA and protein levels as well as global polysome abundance on RNA transcripts. Although presence of the synonymous mutation is clearly causative of such changes, we also demonstrate that fitness benefits are highly contingent on other potentiating mutations present within the genetic background in which the mutation arose. Our results underscore the importance of beneficial synonymous mutations, especially those that affect levels of proteins that are key for cellular processes.IMPORTANCEThis study explores the degree to which synonymous mutations in essential genes can influence adaptation in bacteria. An experimental system whereby an Escherichia coli strain harboring an engineered translation protein elongation factor-Tu (EF-Tu) was subjected to laboratory evolution. We find that a synonymous mutation acquired on the gene encoding for EF-Tu is conditionally beneficial for bacterial fitness. Our findings provide insight into the importance of the genetic background when a synonymous substitution is favored by natural selection and how such changes have the potential to impact evolution when critical cellular processes are involved.
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Affiliation(s)
- Kaitlyn M. McGrath
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona, USA
- School of Plant Sciences, University of Arizona, Tucson, Arizona, USA
| | - Steven J. Russell
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Evrim Fer
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbial Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Eva Garmendia
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Ali Hosgel
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - David A. Baltrus
- School of Plant Sciences, University of Arizona, Tucson, Arizona, USA
| | - Betül Kaçar
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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10
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Teteneva N, Sanches-Medeiros A, Sourjik V. Genome-wide screen of genetic determinants that govern Escherichia coli growth and persistence in lake water. THE ISME JOURNAL 2024; 18:wrae096. [PMID: 38874171 PMCID: PMC11188689 DOI: 10.1093/ismejo/wrae096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/23/2024] [Accepted: 05/31/2024] [Indexed: 06/15/2024]
Abstract
Although enteric bacteria normally reside within the animal intestine, the ability to persist extraintestinally is an essential part of their overall lifestyle, and it might contribute to transmission between hosts. Despite this potential importance, few genetic determinants of extraintestinal growth and survival have been identified, even for the best-studied model, Escherichia coli. In this work, we thus used a genome-wide library of barcoded transposon insertions to systematically identify functional clusters of genes that are crucial for E. coli fitness in lake water. Our results revealed that inactivation of pathways involved in maintaining outer membrane integrity, nucleotide biosynthesis, and chemotaxis negatively affected E. coli growth or survival in this extraintestinal environment. In contrast, inactivation of another group of genes apparently benefited E. coli growth or persistence in filtered lake water, resulting in higher abundance of these mutants. This group included rpoS, which encodes the general stress response sigma factor, as well as genes encoding several other global transcriptional regulators and RNA chaperones, along with several poorly annotated genes. Based on this co-enrichment, we identified these gene products as novel positive regulators of RpoS activity. We further observed that, despite their enhanced growth, E. coli mutants with inactive RpoS had reduced viability in lake water, and they were not enriched in the presence of the autochthonous microbiota. This highlights the duality of the general stress response pathway for E. coli growth outside the host.
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Affiliation(s)
- Nataliya Teteneva
- Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), D-35043 Marburg, Germany
| | - Ananda Sanches-Medeiros
- Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), D-35043 Marburg, Germany
| | - Victor Sourjik
- Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), D-35043 Marburg, Germany
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11
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Xiao Z, Li K, Li T, Zhang F, Xue J, Zhao M, Yin H. Characterization and Mechanism Study of a Novel PL7 Family Exolytic Alginate Lyase from Marine Bacteria Vibrio sp. W13. Appl Biochem Biotechnol 2024; 196:68-84. [PMID: 37099125 DOI: 10.1007/s12010-023-04483-0] [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] [Accepted: 04/11/2023] [Indexed: 04/27/2023]
Abstract
Alginate lyase can degrade alginate into oligosaccharides through β-elimination for various biological, biorefinery, and agricultural purposes. Here, we report a novel PL7 family exolytic alginate lyase VwAlg7A from marine bacteria Vibrio sp. W13 and achieve the heterologous expression in E. coli BL21 (DE3). VwAlg7A is 348aa with a calculated molecular weight of 36 kDa, containing an alginate lyase 2 domain. VwAlg7A exhibits specificity towards poly-guluronate. The optimal temperature and pH of VwAlg7A are 30 °C and 7.0, respectively. The activity of VwAlg7A can be significantly inhibited by the Ni2+, Zn2+, and NaCl. The Km and Vmax of VwAlg7A are 36.9 mg/ml and 395.6 μM/min, respectively. The ESI and HPAEC-PAD results indicate that VwAlg7A cleaves the sugar bond in an exolytic mode. Based on the molecular docking and mutagenesis results, we further confirmed that R98, H169, and Y303 are important catalytic residues.
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Affiliation(s)
- Zhongbin Xiao
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- Department of Materials and Chemicals, Dalian Polytechnic University, Dalian, 116023, China
| | - Kuikui Li
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Tang Li
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Fanxing Zhang
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- Department of Materials and Chemicals, Dalian Polytechnic University, Dalian, 116023, China
| | - Jiayi Xue
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
- Department of Materials and Chemicals, Dalian Polytechnic University, Dalian, 116023, China
| | - Miao Zhao
- Department of Materials and Chemicals, Dalian Polytechnic University, Dalian, 116023, China
| | - Heng Yin
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
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12
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Bryant OJ, Lastovka F, Powell J, Chung BYW. The distinct translational landscapes of gram-negative Salmonella and gram-positive Listeria. Nat Commun 2023; 14:8167. [PMID: 38071303 PMCID: PMC10710512 DOI: 10.1038/s41467-023-43759-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 11/17/2023] [Indexed: 12/18/2023] Open
Abstract
Translational control in pathogenic bacteria is fundamental to gene expression and affects virulence and other infection phenotypes. We used an enhanced ribosome profiling protocol coupled with parallel transcriptomics to capture accurately the global translatome of two evolutionarily distant pathogenic bacteria-the Gram-negative bacterium Salmonella and the Gram-positive bacterium Listeria. We find that the two bacteria use different mechanisms to translationally regulate protein synthesis. In Salmonella, in addition to the expected correlation between translational efficiency and cis-regulatory features such as Shine-Dalgarno (SD) strength and RNA secondary structure around the initiation codon, our data reveal an effect of the 2nd and 3rd codons, where the presence of tandem lysine codons (AAA-AAA) enhances translation in both Salmonella and E. coli. Strikingly, none of these features are seen in efficiently translated Listeria transcripts. Instead, approximately 20% of efficiently translated Listeria genes exhibit 70 S footprints seven nt upstream of the authentic start codon, suggesting that these genes may be subject to a novel translational initiation mechanism. Our results show that SD strength is not a direct hallmark of translational efficiency in all bacteria. Instead, Listeria has evolved additional mechanisms to control gene expression level that are distinct from those utilised by Salmonella and E. coli.
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Affiliation(s)
- Owain J Bryant
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
- Centre for Structural Biology, National Cancer Institute, 21702, Frederick, MD, USA
| | - Filip Lastovka
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Jessica Powell
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Betty Y-W Chung
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK.
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13
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Ferguson L, Upton HE, Pimentel SC, Mok A, Lareau LF, Collins K, Ingolia NT. Streamlined and sensitive mono- and di-ribosome profiling in yeast and human cells. Nat Methods 2023; 20:1704-1715. [PMID: 37783882 PMCID: PMC11276118 DOI: 10.1038/s41592-023-02028-1] [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: 01/18/2023] [Accepted: 08/23/2023] [Indexed: 10/04/2023]
Abstract
Ribosome profiling has unveiled diverse regulation and perturbations of translation through a transcriptome-wide survey of ribosome occupancy, read out by sequencing of ribosome-protected messenger RNA fragments. Generation of ribosome footprints and their conversion into sequencing libraries is technically demanding and sensitive to biases that distort the representation of physiological ribosome occupancy. We address these challenges by producing ribosome footprints with P1 nuclease rather than RNase I and replacing RNA ligation with ordered two-template relay, a single-tube protocol for sequencing library preparation that incorporates adaptors by reverse transcription. Our streamlined approach reduced sequence bias and enhanced enrichment of ribosome footprints relative to ribosomal RNA. Furthermore, P1 nuclease preserved distinct juxtaposed ribosome complexes informative about yeast and human ribosome fates during translation initiation, stalling and termination. Our optimized methods for mRNA footprint generation and capture provide a richer translatome profile with low input and fewer technical challenges.
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Affiliation(s)
- Lucas Ferguson
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
- Center for Computational Biology, University of California, Berkeley, CA, USA.
| | - Heather E Upton
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Sydney C Pimentel
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Amanda Mok
- Center for Computational Biology, University of California, Berkeley, CA, USA
| | - Liana F Lareau
- Center for Computational Biology, University of California, Berkeley, CA, USA
- Department of Bioengineering, University of California, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | - Kathleen Collins
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA.
| | - Nicholas T Ingolia
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA.
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14
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McGrath KM, Russell SJ, Fer E, Garmendia E, Hosgel A, Baltrus DA, Kaçar B. A beneficial synonymous substitution in EF-Tu is contingent on genetic background. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.06.555949. [PMID: 37886545 PMCID: PMC10602032 DOI: 10.1101/2023.09.06.555949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
Synonymous mutations are changes to DNA sequence that occur within translated genes but which do not affect the protein sequence. Although often referred to as silent mutations, evidence suggests that synonymous mutations can affect gene expression, mRNA stability, and even translation efficiency. A collection of both experimental and bioinformatic data has shown that synonymous mutations can impact cell phenotype, yet less is known about the molecular mechanisms and potential of beneficial or adaptive effects of such changes within evolved populations. Here, we report a beneficial synonymous mutation acquired via experimental evolution in an essential gene variant encoding the translation Elongation Factor protein EF-Tu. We demonstrate that this particular synonymous mutation increases EF-Tu mRNA and protein levels, as well as the polysome abundance on global transcripts. Although presence of the synonymous mutation is clearly causative of such changes, we also demonstrate that fitness benefits are highly contingent on other potentiating mutations present within the genetic background in which the mutation arose. Our results underscore the importance of beneficial synonymous mutations, especially those that affect levels of proteins that are key for cellular processes.
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Affiliation(s)
- Kaitlyn M. McGrath
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
- School of Plant Sciences, University of Arizona, Tucson, AZ, USA
| | - Steven J. Russell
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Evrim Fer
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
- Microbial Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Eva Garmendia
- Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden
| | - Ali Hosgel
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - David A. Baltrus
- School of Plant Sciences, University of Arizona, Tucson, AZ, USA
| | - Betül Kaçar
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
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15
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Chen X, Kaiser CM. AP profiling resolves co-translational folding pathway and chaperone interactions in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.01.555749. [PMID: 37693575 PMCID: PMC10491307 DOI: 10.1101/2023.09.01.555749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Natural proteins have evolved to fold robustly along specific pathways. Folding begins during synthesis, guided by interactions of the nascent protein with the ribosome and molecular chaperones. However, the timing and progression of co-translational folding remain largely elusive, in part because the process is difficult to measure in the natural environment of the cytosol. We developed a high-throughput method to quantify co-translational folding in live cells that we term Arrest Peptide profiling (AP profiling). We employed AP profiling to delineate co-translational folding for a set of GTPase domains with very similar structures, defining how topology shapes folding pathways. Genetic ablation of major nascent chain-binding chaperones resulted in localized folding changes that suggest how functional redundancies among chaperones are achieved by distinct interactions with the nascent protein. Collectively, our studies provide a window into cellular folding pathways of complex proteins and pave the way for systematic studies on nascent protein folding at unprecedented resolution and throughput.
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Affiliation(s)
- Xiuqi Chen
- CMDB Graduate Program, Johns Hopkins University, Baltimore, MD, United States
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
- Present address: Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Delft, the Netherlands
| | - Christian M. Kaiser
- Department of Biology, Johns Hopkins University, Baltimore, MD, United States
- Department of Biophysics, Johns Hopkins University, Baltimore, MD, United States
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16
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Höpfler M, Hegde RS. Control of mRNA fate by its encoded nascent polypeptide. Mol Cell 2023; 83:2840-2855. [PMID: 37595554 PMCID: PMC10501990 DOI: 10.1016/j.molcel.2023.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/03/2023] [Accepted: 07/11/2023] [Indexed: 08/20/2023]
Abstract
Cells tightly regulate mRNA processing, localization, and stability to ensure accurate gene expression in diverse cellular states and conditions. Most of these regulatory steps have traditionally been thought to occur before translation by the action of RNA-binding proteins. Several recent discoveries highlight multiple co-translational mechanisms that modulate mRNA translation, localization, processing, and stability. These mechanisms operate by recognition of the nascent protein, which is necessarily coupled to its encoding mRNA during translation. Hence, the distinctive sequence or structure of a particular nascent chain can recruit recognition factors with privileged access to the corresponding mRNA in an otherwise crowded cellular environment. Here, we draw on both well-established and recent examples to provide a conceptual framework for how cells exploit nascent protein recognition to direct mRNA fate. These mechanisms allow cells to dynamically and specifically regulate their transcriptomes in response to changes in cellular states to maintain protein homeostasis.
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17
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Allen WJ, Collinson I. A unifying mechanism for protein transport through the core bacterial Sec machinery. Open Biol 2023; 13:230166. [PMID: 37643640 PMCID: PMC10465204 DOI: 10.1098/rsob.230166] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/21/2023] [Indexed: 08/31/2023] Open
Abstract
Encapsulation and compartmentalization are fundamental to the evolution of cellular life, but they also pose a challenge: how to partition the molecules that perform biological functions-the proteins-across impermeable barriers into sub-cellular organelles, and to the outside. The solution lies in the evolution of specialized machines, translocons, found in every biological membrane, which act both as gate and gatekeeper across and into membrane bilayers. Understanding how these translocons operate at the molecular level has been a long-standing ambition of cell biology, and one that is approaching its denouement; particularly in the case of the ubiquitous Sec system. In this review, we highlight the fruits of recent game-changing technical innovations in structural biology, biophysics and biochemistry to present a largely complete mechanism for the bacterial version of the core Sec machinery. We discuss the merits of our model over alternative proposals and identify the remaining open questions. The template laid out by the study of the Sec system will be of immense value for probing the many other translocons found in diverse biological membranes, towards the ultimate goal of altering or impeding their functions for pharmaceutical or biotechnological purposes.
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Affiliation(s)
- William J. Allen
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, UK
| | - Ian Collinson
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, UK
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18
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Meindl A, Romberger M, Lehmann G, Eichner N, Kleemann L, Wu J, Danner J, Boesl M, Mesitov M, Meister G, König J, Leidel S, Medenbach J. A rapid protocol for ribosome profiling of low input samples. Nucleic Acids Res 2023; 51:e68. [PMID: 37246712 PMCID: PMC10359457 DOI: 10.1093/nar/gkad459] [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: 10/28/2022] [Revised: 05/04/2023] [Accepted: 05/13/2023] [Indexed: 05/30/2023] Open
Abstract
Ribosome profiling provides quantitative, comprehensive, and high-resolution snapshots of cellular translation by the high-throughput sequencing of short mRNA fragments that are protected by ribosomes from nucleolytic digestion. While the overall principle is simple, the workflow of ribosome profiling experiments is complex and challenging, and typically requires large amounts of sample, limiting its broad applicability. Here, we present a new protocol for ultra-rapid ribosome profiling from low-input samples. It features a robust strategy for sequencing library preparation within one day that employs solid phase purification of reaction intermediates, allowing to reduce the input to as little as 0.1 pmol of ∼30 nt RNA fragments. Hence, it is particularly suited for the analyses of small samples or targeted ribosome profiling. Its high sensitivity and its ease of implementation will foster the generation of higher quality data from small samples, which opens new opportunities in applying ribosome profiling.
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Affiliation(s)
- Andreas Meindl
- Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Markus Romberger
- Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Gerhard Lehmann
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Norbert Eichner
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Leon Kleemann
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Jie Wu
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Johannes Danner
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Maria Boesl
- Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | | | - Gunter Meister
- Biochemistry I, University of Regensburg, Regensburg, Germany
| | - Julian König
- Institute of Molecular Biology (IMB), Mainz, Germany
| | - Sebastian Andreas Leidel
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Jan Medenbach
- Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
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19
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Müller MBD, Kasturi P, Jayaraj GG, Hartl FU. Mechanisms of readthrough mitigation reveal principles of GCN1-mediated translational quality control. Cell 2023:S0092-8674(23)00587-1. [PMID: 37339632 PMCID: PMC10364623 DOI: 10.1016/j.cell.2023.05.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 05/17/2023] [Accepted: 05/24/2023] [Indexed: 06/22/2023]
Abstract
Readthrough into the 3' untranslated region (3' UTR) of the mRNA results in the production of aberrant proteins. Metazoans efficiently clear readthrough proteins, but the underlying mechanisms remain unknown. Here, we show in Caenorhabditis elegans and mammalian cells that readthrough proteins are targeted by a coupled, two-level quality control pathway involving the BAG6 chaperone complex and the ribosome-collision-sensing protein GCN1. Readthrough proteins with hydrophobic C-terminal extensions (CTEs) are recognized by SGTA-BAG6 and ubiquitylated by RNF126 for proteasomal degradation. Additionally, cotranslational mRNA decay initiated by GCN1 and CCR4/NOT limits the accumulation of readthrough products. Unexpectedly, selective ribosome profiling uncovered a general role of GCN1 in regulating translation dynamics when ribosomes collide at nonoptimal codons, enriched in 3' UTRs, transmembrane proteins, and collagens. GCN1 dysfunction increasingly perturbs these protein classes during aging, resulting in mRNA and proteome imbalance. Our results define GCN1 as a key factor acting during translation in maintaining protein homeostasis.
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Affiliation(s)
- Martin B D Müller
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Prasad Kasturi
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Gopal G Jayaraj
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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20
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Seidel M, Romanov N, Obarska-Kosinska A, Becker A, Trevisan Doimo de Azevedo N, Provaznik J, Nagaraja SR, Landry JJM, Benes V, Beck M. Co-translational binding of importins to nascent proteins. Nat Commun 2023; 14:3418. [PMID: 37296145 PMCID: PMC10256725 DOI: 10.1038/s41467-023-39150-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
Various cellular quality control mechanisms support proteostasis. While, ribosome-associated chaperones prevent the misfolding of nascent chains during translation, importins were shown to prevent the aggregation of specific cargoes in a post-translational mechanism prior the import into the nucleoplasm. Here, we hypothesize that importins may already bind ribosome-associated cargo in a co-translational manner. We systematically measure the nascent chain association of all importins in Saccharomyces cerevisiae by selective ribosome profiling. We identify a subset of importins that bind to a wide range of nascent, often uncharacterized cargoes. This includes ribosomal proteins, chromatin remodelers and RNA binding proteins that are aggregation prone in the cytosol. We show that importins act consecutively with other ribosome-associated chaperones. Thus, the nuclear import system is directly intertwined with nascent chain folding and chaperoning.
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Affiliation(s)
- Maximilian Seidel
- Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
- Faculty of Bioscience, Heidelberg University, Heidelberg, Germany
| | - Natalie Romanov
- Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | | | - Anja Becker
- Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | | | - Jan Provaznik
- Genomics Core Facility, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Sankarshana R Nagaraja
- Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Jonathan J M Landry
- Genomics Core Facility, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Vladimir Benes
- Genomics Core Facility, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Martin Beck
- Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany.
- Institute of Biochemistry, Goethe University Frankfurt, Frankfurt, Germany.
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21
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Moon S, Ham S, Jeong J, Ku H, Kim H, Lee C. Temperature Matters: Bacterial Response to Temperature Change. J Microbiol 2023; 61:343-357. [PMID: 37010795 DOI: 10.1007/s12275-023-00031-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/13/2023] [Accepted: 02/13/2023] [Indexed: 04/04/2023]
Abstract
Temperature is one of the most important factors in all living organisms for survival. Being a unicellular organism, bacterium requires sensitive sensing and defense mechanisms to tolerate changes in temperature. During a temperature shift, the structure and composition of various cellular molecules including nucleic acids, proteins, and membranes are affected. In addition, numerous genes are induced during heat or cold shocks to overcome the cellular stresses, which are known as heat- and cold-shock proteins. In this review, we describe the cellular phenomena that occur with temperature change and bacterial responses from a molecular perspective, mainly in Escherichia coli.
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Affiliation(s)
- Seongjoon Moon
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Soojeong Ham
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Juwon Jeong
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Heechan Ku
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea
| | - Hyunhee Kim
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea.
| | - Changhan Lee
- Department of Biological Sciences, Ajou University, Suwon, 16499, Republic of Korea.
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22
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Majumdar S, Deep A, Sharma MR, Canestrari J, Stone M, Smith C, Koripella RK, Keshavan P, Banavali NK, Wade JT, Gray TA, Derbyshire KM, Agrawal RK. The small mycobacterial ribosomal protein, bS22, modulates aminoglycoside accessibility to its 16S rRNA helix-44 binding site. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535098. [PMID: 37034768 PMCID: PMC10081302 DOI: 10.1101/2023.03.31.535098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Treatment of tuberculosis continues to be challenging due to the widespread latent form of the disease and the emergence of antibiotic-resistant strains of the pathogen, Mycobacterium tuberculosis. Bacterial ribosomes are a common and effective target for antibiotics. Several second line anti-tuberculosis drugs, e.g. kanamycin, amikacin, and capreomycin, target ribosomal RNA to inhibit protein synthesis. However, M. tuberculosis can acquire resistance to these drugs, emphasizing the need to identify new drug targets. Previous cryo-EM structures of the M. tuberculosis and M. smegmatis ribosomes identified two novel ribosomal proteins, bS22 and bL37, in the vicinity of two crucial drug-binding sites: the mRNA-decoding center on the small (30S), and the peptidyl-transferase center on the large (50S) ribosomal subunits, respectively. The functional significance of these two small proteins is unknown. In this study, we observe that an M. smegmatis strain lacking the bs22 gene shows enhanced susceptibility to kanamycin compared to the wild-type strain. Cryo-EM structures of the ribosomes lacking bS22 in the presence and absence of kanamycin suggest a direct role of bS22 in modulating the 16S rRNA kanamycin-binding site. Our structures suggest that amino-acid residue Lys-16 of bS22 interacts directly with the phosphate backbone of helix 44 of 16S rRNA to influence the micro-configuration of the kanamycin-binding pocket. Our analysis shows that similar interactions occur between eukaryotic homologues of bS22, and their corresponding rRNAs, pointing to a common mechanism of aminoglycoside resistance in higher organisms.
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Affiliation(s)
| | - Ayush Deep
- Division of Translational Medicine, Albany, NY 12237
| | | | - Jill Canestrari
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
| | - Melissa Stone
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
| | - Carol Smith
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
| | | | | | - Nilesh K Banavali
- Division of Translational Medicine, Albany, NY 12237
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY 12222
| | - Joseph T Wade
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY 12222
| | - Todd A Gray
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY 12222
| | - Keith M Derbyshire
- Division of Genetics, Wadsworth Center, New York State, Department of Health, Albany, NY 12237
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY 12222
| | - Rajendra K Agrawal
- Division of Translational Medicine, Albany, NY 12237
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY 12222
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23
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Günnigmann M, Koubek J, Kramer G, Bukau B. Selective ribosome profiling as a tool to study interactions of translating ribosomes in mammalian cells. Methods Enzymol 2023; 684:1-38. [PMID: 37230585 DOI: 10.1016/bs.mie.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The processing, membrane targeting and folding of newly synthesized polypeptides is closely linked to their synthesis at the ribosome. A network of enzymes, chaperones and targeting factors engages ribosome-nascent chain complexes (RNCs) to support these maturation processes. Exploring the modes of action of this machinery is critical for our understanding of functional protein biogenesis. Selective ribosome profiling (SeRP) is a powerful method for interrogating co-translational interactions of maturation factors with RNCs. It provides proteome-wide information on the factor's nascent chain interactome, the timing of factor binding and release during the progress of translation of individual nascent chain species, and the mechanisms and features controlling factor engagement. SeRP is based on the combination of two ribosome profiling (RP) experiments performed on the same cell population. In one experiment the ribosome-protected mRNA footprints of all translating ribosomes of the cell are sequenced (total translatome), while the other experiment detects only the ribosome footprints of the subpopulation of ribosomes engaged by the factor of interest (selected translatome). The codon-specific ratio of ribosome footprint densities from selected over total translatome reports on the factor enrichment at specific nascent chains. In this chapter, we provide a detailed SeRP protocol for mammalian cells. The protocol includes instructions on cell growth and cell harvest, stabilization of factor-RNC interactions, nuclease digest and purification of (factor-engaged) monosomes, as well as preparation of cDNA libraries from ribosome footprint fragments and deep sequencing data analysis. Purification protocols of factor-engaged monosomes and experimental results are exemplified for the human ribosomal tunnel exit-binding factor Ebp1 and chaperone Hsp90, but the protocols are readily adaptable to other co-translationally acting mammalian factors.
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Affiliation(s)
- Manuel Günnigmann
- Center for Molecular Biology of Heidelberg University (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Jiří Koubek
- Center for Molecular Biology of Heidelberg University (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Günter Kramer
- Center for Molecular Biology of Heidelberg University (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Bernd Bukau
- Center for Molecular Biology of Heidelberg University (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Heidelberg, Germany.
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24
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Kohler V, Andréasson C. Reversible protein assemblies in the proteostasis network in health and disease. Front Mol Biosci 2023; 10:1155521. [PMID: 37021114 PMCID: PMC10067754 DOI: 10.3389/fmolb.2023.1155521] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/09/2023] [Indexed: 04/07/2023] Open
Abstract
While proteins populating their native conformations constitute the functional entities of cells, protein aggregates are traditionally associated with cellular dysfunction, stress and disease. During recent years, it has become clear that large aggregate-like protein condensates formed via liquid-liquid phase separation age into more solid aggregate-like particles that harbor misfolded proteins and are decorated by protein quality control factors. The constituent proteins of the condensates/aggregates are disentangled by protein disaggregation systems mainly based on Hsp70 and AAA ATPase Hsp100 chaperones prior to their handover to refolding and degradation systems. Here, we discuss the functional roles that condensate formation/aggregation and disaggregation play in protein quality control to maintain proteostasis and why it matters for understanding health and disease.
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Affiliation(s)
- Verena Kohler
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Claes Andréasson
- Department of Molecular Biosciences, Stockholm University, Stockholm, Sweden
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25
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Bögeholz LA, Mercier E, Wintermeyer W, Rodnina MV. Deformylation of nascent peptide chains on the ribosome. Methods Enzymol 2023; 684:39-70. [DOI: 10.1016/bs.mie.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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26
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Eismann L, Fijalkowski I, Galmozzi CV, Koubek J, Tippmann F, Van Damme P, Kramer G. Selective ribosome profiling reveals a role for SecB in the co-translational inner membrane protein biogenesis. Cell Rep 2022; 41:111776. [PMID: 36476862 DOI: 10.1016/j.celrep.2022.111776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 10/04/2022] [Accepted: 11/11/2022] [Indexed: 12/12/2022] Open
Abstract
The chaperone SecB has been implicated in de novo protein folding and translocation across the membrane, but it remains unclear which nascent polypeptides SecB binds, when during translation SecB acts, how SecB function is coordinated with other chaperones and targeting factors, and how polypeptide engagement contributes to protein biogenesis. Using selective ribosome profiling, we show that SecB binds many nascent cytoplasmic and translocated proteins generally late during translation and controlled by the chaperone trigger factor. Revealing an uncharted role in co-translational translocation, inner membrane proteins (IMPs) are the most prominent nascent SecB interactors. Unlike other substrates, IMPs are bound early during translation, following the membrane targeting by the signal recognition particle. SecB remains bound until translation is terminated, and contributes to membrane insertion. Our study establishes a role of SecB in the co-translational maturation of proteins from all cellular compartments and functionally implicates cytosolic chaperones in membrane protein biogenesis.
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Affiliation(s)
- Lena Eismann
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Igor Fijalkowski
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
| | - Carla Verónica Galmozzi
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/ Universidad de Sevilla, 41013 Seville, Spain
| | - Jiří Koubek
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Frank Tippmann
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Petra Van Damme
- iRIP Unit, Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, 9000 Ghent, Belgium
| | - Günter Kramer
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany.
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27
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Abstract
In bacteria, transcription and translation take place in the same cellular compartment. Therefore, a messenger RNA can be translated as it is being transcribed, a process known as transcription-translation coupling. This process was already recognized at the dawn of molecular biology, yet the interplay between the two key players, the RNA polymerase and ribosome, remains elusive. Genetic data indicate that an RNA sequence can be translated shortly after it has been transcribed. The closer both processes are in time, the less accessible the RNA sequence is between the RNA polymerase and ribosome. This temporal coupling has important consequences for gene regulation. Biochemical and structural studies have detailed several complexes between the RNA polymerase and ribosome. The in vivo relevance of this physical coupling has not been formally demonstrated. We discuss how both temporal and physical coupling may mesh to produce the phenomenon we know as transcription-translation coupling.
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Affiliation(s)
- Gregor M Blaha
- Department of Biochemistry, University of California, Riverside, California, USA;
| | - Joseph T Wade
- Wadsworth Center, New York State Department of Health, Albany, New York, USA;
- Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, New York, USA
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28
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Hör J, Jung J, Ðurica-Mitić S, Barquist L, Vogel J. INRI-seq enables global cell-free analysis of translation initiation and off-target effects of antisense inhibitors. Nucleic Acids Res 2022; 50:e128. [PMID: 36229039 PMCID: PMC9825163 DOI: 10.1093/nar/gkac838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 09/11/2022] [Accepted: 09/19/2022] [Indexed: 01/29/2023] Open
Abstract
Ribosome profiling (Ribo-seq) is a powerful method for the transcriptome-wide assessment of protein synthesis rates and the study of translational control mechanisms. Yet, Ribo-seq also has limitations. These include difficulties with the analysis of translation-modulating molecules such as antibiotics, which are often toxic or challenging to deliver into living cells. Here, we have developed in vitro Ribo-seq (INRI-seq), a cell-free method to analyze the translational landscape of a fully customizable synthetic transcriptome. Using Escherichia coli as an example, we show how INRI-seq can be used to analyze the translation initiation sites of a transcriptome of interest. We also study the global impact of direct translation inhibition by antisense peptide nucleic acid (PNA) to analyze PNA off-target effects. Overall, INRI-seq presents a scalable, sensitive method to study translation initiation in a transcriptome-wide manner without the potentially confounding effects of extracting ribosomes from living cells.
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Affiliation(s)
- Jens Hör
- Institute for Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Jakob Jung
- Institute for Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Svetlana Ðurica-Mitić
- Institute for Molecular Infection Biology, University of Würzburg, D-97080 Würzburg, Germany
| | - Lars Barquist
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), D-97080 Würzburg, Germany,Faculty of Medicine, University of Würzburg, D-97080 Würzburg, Germany
| | - Jörg Vogel
- To whom correspondence should be addressed. Tel: +49 931 3182576;
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29
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Mangano K, Marks J, Klepacki D, Saha CK, Atkinson GC, Vázquez-Laslop N, Mankin AS. Context-based sensing of orthosomycin antibiotics by the translating ribosome. Nat Chem Biol 2022; 18:1277-1286. [PMID: 36138139 DOI: 10.1038/s41589-022-01138-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 08/10/2022] [Indexed: 11/09/2022]
Abstract
Orthosomycin antibiotics inhibit protein synthesis by binding to the large ribosomal subunit in the tRNA accommodation corridor, which is traversed by incoming aminoacyl-tRNAs. Structural and biochemical studies suggested that orthosomycins block accommodation of any aminoacyl-tRNAs in the ribosomal A-site. However, the mode of action of orthosomycins in vivo remained unknown. Here, by carrying out genome-wide analysis of antibiotic action in bacterial cells, we discovered that orthosomycins primarily inhibit the ribosomes engaged in translation of specific amino acid sequences. Our results reveal that the predominant sites of orthosomycin-induced translation arrest are defined by the nature of the incoming aminoacyl-tRNA and likely by the identity of the two C-terminal amino acid residues of the nascent protein. We show that nature exploits this antibiotic-sensing mechanism for directing programmed ribosome stalling within the regulatory open reading frame, which may control expression of an orthosomycin-resistance gene in a variety of bacterial species.
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Affiliation(s)
- Kyle Mangano
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL, USA.,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL, USA.,Amgen Research, Thousand Oaks, CA, USA
| | - James Marks
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL, USA.,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL, USA.,National Institute of Arthritis and Musculoskeletal and Skin Disease, Bethesda, MD, USA
| | - Dorota Klepacki
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL, USA.,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Chayan Kumar Saha
- Department of Experimental Medicine, Lund University, Lund, Sweden.,Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Gemma C Atkinson
- Department of Experimental Medicine, Lund University, Lund, Sweden
| | - Nora Vázquez-Laslop
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL, USA. .,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL, USA.
| | - Alexander S Mankin
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL, USA. .,Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, IL, USA.
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30
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García-Santibañez T, Rosenblueth M, Bolaños LM, Martínez-Romero J, Martínez-Romero E. The divergent genome of Scorpion Group 1 (SG1) intracellular bacterium from the venom glands of Vaejovis smithi (Scorpiones: Vaejovidae). Syst Appl Microbiol 2022; 45:126358. [PMID: 36174465 DOI: 10.1016/j.syapm.2022.126358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/12/2022] [Accepted: 09/07/2022] [Indexed: 10/31/2022]
Abstract
Scorpions were among the first animals on land around 430 million years ago. Like many arachnids, scorpions have evolved complex venoms used to paralyze their prey and for self-defense. Here we sequenced and analyzed the metagenomic DNA from venom glands from Vaejovis smithi scorpions. A metagenome-assembled genome (MAG) of 624,025 bp was obtained corresponding to the previously reported Scorpion Group 1 (SG1). The SG1 genome from venom glands had a low GC content (25.8%) characteristic of reduced genomes, many hypothetical genes and genes from the reported minimal set of bacterial genes. Phylogenomic reconstructions placed the uncultured SG1 distant from other reported bacteria constituting a taxonomic novelty. By PCR we detected SG1 in all tested venom glands from 30 independent individuals. Microscopically, we observed SG1 inside epithelial cells from the venom glands using FISH and its presence in scorpion embryos suggested that SG1 is transferred from mother to offspring.
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Affiliation(s)
| | - Mónica Rosenblueth
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Luis M Bolaños
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico; School of Biosciences, University of Exeter, Exeter, UK
| | - Julio Martínez-Romero
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
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31
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Niwa T, Nakazawa K, Hoshi K, Tadakuma H, Ito K, Taguchi H. Application of fluorescence correlation spectroscopy to investigate the dynamics of a ribosome-associated trigger factor in Escherichia coli. Front Mol Biosci 2022; 9:891128. [PMID: 36090041 PMCID: PMC9452904 DOI: 10.3389/fmolb.2022.891128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/26/2022] [Indexed: 11/15/2022] Open
Abstract
Co-translational protein folding is one of the central topics in molecular biology. In Escherichia coli, trigger factor (TF) is a primary chaperone that facilitates co-translational folding by directly interacting with nascent polypeptide chains on translating ribosomes. In this study, we applied fluorescence correlation spectroscopy (FCS), which can analyze the diffusion properties of fluorescent molecules by measuring the fluctuations of the fluorescent intensity, to investigate the interaction between TF and a nascent chain on translating ribosomes both in vitro and in vivo. The FCS analysis with a reconstituted cell-free translation system revealed that the interaction of fluorescently labeled TF with a nascent chain depended on the emergence of the nascent chain from the ribosome exit tunnel, and this interaction was not inhibited by excess amounts of other chaperones. Furthermore, the translation-dependent interaction between GFP-fused TFs and nascent chains was also observed in living E. coli cells. The FCS-based approach established here could be an effective method to investigate the dynamics of other ribosome-associated chaperones besides TF.
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Affiliation(s)
- Tatsuya Niwa
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Koki Nakazawa
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Kensuke Hoshi
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Hisashi Tadakuma
- School of Life Science and Technology and Gene Editing Center, ShanghaiTech University, Shanghai, China
| | - Koichi Ito
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Hideki Taguchi
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
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32
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A New Factor LapD Is Required for the Regulation of LpxC Amounts and Lipopolysaccharide Trafficking. Int J Mol Sci 2022; 23:ijms23179706. [PMID: 36077106 PMCID: PMC9456370 DOI: 10.3390/ijms23179706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/20/2022] [Accepted: 08/23/2022] [Indexed: 11/17/2022] Open
Abstract
Lipopolysaccharide (LPS) constitutes the major component of the outer membrane and is essential for bacteria, such as Escherichia coli. Recent work has revealed the essential roles of LapB and LapC proteins in regulating LPS amounts; although, if any additional partners are involved is unknown. Examination of proteins co-purifying with LapB identified LapD as a new partner. The purification of LapD reveals that it forms a complex with several proteins involved in LPS and phospholipid biosynthesis, including FtsH-LapA/B and Fab enzymes. Loss of LapD causes a reduction in LpxC amounts and vancomycin sensitivity, which can be restored by mutations that stabilize LpxC (mutations in lapB, ftsH and lpxC genes), revealing that LapD acts upstream of LapB-FtsH in regulating LpxC amounts. Interestingly, LapD absence results in the substantial retention of LPS in the inner membranes and synthetic lethality when either the lauroyl or the myristoyl acyl transferase is absent, which can be overcome by single-amino acid suppressor mutations in LPS flippase MsbA, suggesting LPS translocation defects in ΔlapD bacteria. Several genes whose products are involved in cell envelope homeostasis, including clsA, waaC, tig and micA, become essential in LapD’s absence. Furthermore, the overproduction of acyl carrier protein AcpP or transcriptional factors DksA, SrrA can overcome certain defects of the LapD-lacking strain.
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33
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Sawyer EB, Cortes T. Ribosome profiling enhances understanding of mycobacterial translation. Front Microbiol 2022; 13:976550. [PMID: 35992675 PMCID: PMC9386245 DOI: 10.3389/fmicb.2022.976550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/22/2022] [Indexed: 11/21/2022] Open
Abstract
A recent addition to the -omics toolkit, ribosome profiling, enables researchers to gain insight into the process and regulation of translation by mapping fragments of mRNA protected from nuclease digestion by ribosome binding. In this review, we discuss how ribosome profiling applied to mycobacteria has led to discoveries about translational regulation. Using case studies, we show that the traditional view of “canonical” translation mechanisms needs expanding to encompass features of mycobacterial translation that are more widespread than previously recognized. We also discuss the limitations of the method and potential future developments that could yield further insight into the fundamental biology of this important human pathogen.
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Affiliation(s)
- Elizabeth B. Sawyer
- School of Life Sciences, University of Westminster, London, United Kingdom
- *Correspondence: Elizabeth B. Sawyer,
| | - Teresa Cortes
- Pathogen Gene Regulation Unit, Instituto de Biomedicina de Valencia (IBV), CSIC, Valencia, Spain
- Teresa Cortes,
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34
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Kaderabkova N, Bharathwaj M, Furniss RCD, Gonzalez D, Palmer T, Mavridou DAI. The biogenesis of β-lactamase enzymes. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35943884 DOI: 10.1099/mic.0.001217] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The discovery of penicillin by Alexander Fleming marked a new era for modern medicine, allowing not only the treatment of infectious diseases, but also the safe performance of life-saving interventions, like surgery and chemotherapy. Unfortunately, resistance against penicillin, as well as more complex β-lactam antibiotics, has rapidly emerged since the introduction of these drugs in the clinic, and is largely driven by a single type of extra-cytoplasmic proteins, hydrolytic enzymes called β-lactamases. While the structures, biochemistry and epidemiology of these resistance determinants have been extensively characterized, their biogenesis, a complex process including multiple steps and involving several fundamental biochemical pathways, is rarely discussed. In this review, we provide a comprehensive overview of the journey of β-lactamases, from the moment they exit the ribosomal channel until they reach their final cellular destination as folded and active enzymes.
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Affiliation(s)
- Nikol Kaderabkova
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, USA
| | - Manasa Bharathwaj
- Centre to Impact AMR, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - R Christopher D Furniss
- Science for Life Laboratory, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Diego Gonzalez
- Laboratoire de Microbiologie, Institut de Biologie, Université de Neuchâtel, Neuchâtel, 2000, Switzerland
| | - Tracy Palmer
- Microbes in Health and Disease, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Despoina A I Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, USA.,John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, Texas, USA
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35
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Badonyi M, Marsh JA. Large protein complex interfaces have evolved to promote cotranslational assembly. eLife 2022; 11:79602. [PMID: 35899946 PMCID: PMC9365393 DOI: 10.7554/elife.79602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Assembly pathways of protein complexes should be precise and efficient to minimise misfolding and unwanted interactions with other proteins in the cell. One way to achieve this efficiency is by seeding assembly pathways during translation via the cotranslational assembly of subunits. While recent evidence suggests that such cotranslational assembly is widespread, little is known about the properties of protein complexes associated with the phenomenon. Here, using a combination of proteome-specific protein complex structures and publicly available ribosome profiling data, we show that cotranslational assembly is particularly common between subunits that form large intermolecular interfaces. To test whether large interfaces have evolved to promote cotranslational assembly, as opposed to cotranslational assembly being a non-adaptive consequence of large interfaces, we compared the sizes of first and last translated interfaces of heteromeric subunits in bacterial, yeast, and human complexes. When considering all together, we observe the N-terminal interface to be larger than the C-terminal interface 54% of the time, increasing to 64% when we exclude subunits with only small interfaces, which are unlikely to cotranslationally assemble. This strongly suggests that large interfaces have evolved as a means to maximise the chance of successful cotranslational subunit binding.
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Affiliation(s)
- Mihaly Badonyi
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom
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36
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Kaushik S, He H, Dalbey RE. Bacterial Signal Peptides- Navigating the Journey of Proteins. Front Physiol 2022; 13:933153. [PMID: 35957980 PMCID: PMC9360617 DOI: 10.3389/fphys.2022.933153] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/21/2022] [Indexed: 11/18/2022] Open
Abstract
In 1971, Blobel proposed the first statement of the Signal Hypothesis which suggested that proteins have amino-terminal sequences that dictate their export and localization in the cell. A cytosolic binding factor was predicted, and later the protein conducting channel was discovered that was proposed in 1975 to align with the large ribosomal tunnel. The 1975 Signal Hypothesis also predicted that proteins targeted to different intracellular membranes would possess distinct signals and integral membrane proteins contained uncleaved signal sequences which initiate translocation of the polypeptide chain. This review summarizes the central role that the signal peptides play as address codes for proteins, their decisive role as targeting factors for delivery to the membrane and their function to activate the translocation machinery for export and membrane protein insertion. After shedding light on the navigation of proteins, the importance of removal of signal peptide and their degradation are addressed. Furthermore, the emerging work on signal peptidases as novel targets for antibiotic development is described.
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37
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Selective footprinting of 40S and 80S ribosome subpopulations (Sel-TCP-seq) to study translation and its control. Nat Protoc 2022; 17:2139-2187. [DOI: 10.1038/s41596-022-00708-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 04/01/2022] [Indexed: 11/08/2022]
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38
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Zhu Z, Wang S, Shan SO. Ribosome profiling reveals multiple roles of SecA in cotranslational protein export. Nat Commun 2022; 13:3393. [PMID: 35697696 PMCID: PMC9192764 DOI: 10.1038/s41467-022-31061-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 05/26/2022] [Indexed: 11/18/2022] Open
Abstract
SecA, an ATPase known to posttranslationally translocate secretory proteins across the bacterial plasma membrane, also binds ribosomes, but the role of SecA’s ribosome interaction has been unclear. Here, we used a combination of ribosome profiling methods to investigate the cotranslational actions of SecA. Our data reveal the widespread accumulation of large periplasmic loops of inner membrane proteins in the cytoplasm during their cotranslational translocation, which are specifically recognized and resolved by SecA in coordination with the proton motive force (PMF). Furthermore, SecA associates with 25% of secretory proteins with highly hydrophobic signal sequences at an early stage of translation and mediates their cotranslational transport. In contrast, the chaperone trigger factor (TF) delays SecA engagement on secretory proteins with weakly hydrophobic signal sequences, thus enforcing a posttranslational mode of their translocation. Our results elucidate the principles of SecA-driven cotranslational protein translocation and reveal a hierarchical network of protein export pathways in bacteria. Using a combination of ribosome profiling methods, Zhu et al. investigate the principles governing the cotranslational interaction of SecA with nascent proteins and reveal a hierarchical organization of protein export pathways in bacteria.
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Affiliation(s)
- Zikun Zhu
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Shuai Wang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.,Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, 94305, USA
| | - Shu-Ou Shan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
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Nissley DA, Jiang Y, Trovato F, Sitarik I, Narayan KB, To P, Xia Y, Fried SD, O’Brien EP. Universal protein misfolding intermediates can bypass the proteostasis network and remain soluble and less functional. Nat Commun 2022; 13:3081. [PMID: 35654797 PMCID: PMC9163053 DOI: 10.1038/s41467-022-30548-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 05/05/2022] [Indexed: 01/12/2023] Open
Abstract
Some misfolded protein conformations can bypass proteostasis machinery and remain soluble in vivo. This is an unexpected observation, as cellular quality control mechanisms should remove misfolded proteins. Three questions, then, are: how do long-lived, soluble, misfolded proteins bypass proteostasis? How widespread are such misfolded states? And how long do they persist? We address these questions using coarse-grain molecular dynamics simulations of the synthesis, termination, and post-translational dynamics of a representative set of cytosolic E. coli proteins. We predict that half of proteins exhibit misfolded subpopulations that bypass molecular chaperones, avoid aggregation, and will not be rapidly degraded, with some misfolded states persisting for months or longer. The surface properties of these misfolded states are native-like, suggesting they will remain soluble, while self-entanglements make them long-lived kinetic traps. In terms of function, we predict that one-third of proteins can misfold into soluble less-functional states. For the heavily entangled protein glycerol-3-phosphate dehydrogenase, limited-proteolysis mass spectrometry experiments interrogating misfolded conformations of the protein are consistent with the structural changes predicted by our simulations. These results therefore provide an explanation for how proteins can misfold into soluble conformations with reduced functionality that can bypass proteostasis, and indicate, unexpectedly, this may be a wide-spread phenomenon.
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Affiliation(s)
- Daniel A. Nissley
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA
| | - Yang Jiang
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA
| | - Fabio Trovato
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA
| | - Ian Sitarik
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA
| | - Karthik B. Narayan
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA
| | - Philip To
- grid.21107.350000 0001 2171 9311Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218 USA
| | - Yingzi Xia
- grid.21107.350000 0001 2171 9311Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218 USA
| | - Stephen D. Fried
- grid.21107.350000 0001 2171 9311Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218 USA ,grid.21107.350000 0001 2171 9311Thomas C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218 USA
| | - Edward P. O’Brien
- grid.29857.310000 0001 2097 4281Department of Chemistry, Pennsylvania State University, University Park, PA 16802 USA ,grid.29857.310000 0001 2097 4281Bioinformatics and Genomics Graduate Program, The Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802 USA ,grid.29857.310000 0001 2097 4281Institute for Computational and Data Sciences, Pennsylvania State University, University Park, PA 16802 USA
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40
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Abstract
The folding of proteins into their native structure is crucial for the functioning of all biological processes. Molecular chaperones are guardians of the proteome that assist in protein folding and prevent the accumulation of aberrant protein conformations that can lead to proteotoxicity. ATP-independent chaperones do not require ATP to regulate their functional cycle. Although these chaperones have been traditionally regarded as passive holdases that merely prevent aggregation, recent work has shown that they can directly affect the folding energy landscape by tuning their affinity to various folding states of the client. This review focuses on emerging paradigms in the mechanism of action of ATP-independent chaperones and on the various modes of regulating client binding and release.
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Affiliation(s)
- Rishav Mitra
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan, USA; .,Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kevin Wu
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan, USA; .,Department of Biophysics, University of Michigan, Ann Arbor, Michigan, USA
| | - Changhan Lee
- Department of Biological Sciences, Ajou University, Suwon, South Korea
| | - James C A Bardwell
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan, USA; .,Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
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41
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Mercier E, Wang X, Bögeholz LAK, Wintermeyer W, Rodnina MV. Cotranslational Biogenesis of Membrane Proteins in Bacteria. Front Mol Biosci 2022; 9:871121. [PMID: 35573737 PMCID: PMC9099147 DOI: 10.3389/fmolb.2022.871121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/12/2022] [Indexed: 12/26/2022] Open
Abstract
Nascent polypeptides emerging from the ribosome during translation are rapidly scanned and processed by ribosome-associated protein biogenesis factors (RPBs). RPBs cleave the N-terminal formyl and methionine groups, assist cotranslational protein folding, and sort the proteins according to their cellular destination. Ribosomes translating inner-membrane proteins are recognized and targeted to the translocon with the help of the signal recognition particle, SRP, and SRP receptor, FtsY. The growing nascent peptide is then inserted into the phospholipid bilayer at the translocon, an inner-membrane protein complex consisting of SecY, SecE, and SecG. Folding of membrane proteins requires that transmembrane helices (TMs) attain their correct topology, the soluble domains are inserted at the correct (cytoplasmic or periplasmic) side of the membrane, and – for polytopic membrane proteins – the TMs find their interaction partner TMs in the phospholipid bilayer. This review describes the recent progress in understanding how growing nascent peptides are processed and how inner-membrane proteins are targeted to the translocon and find their correct orientation at the membrane, with the focus on biophysical approaches revealing the dynamics of the process. We describe how spontaneous fluctuations of the translocon allow diffusion of TMs into the phospholipid bilayer and argue that the ribosome orchestrates cotranslational targeting not only by providing the binding platform for the RPBs or the translocon, but also by helping the nascent chains to find their correct orientation in the membrane. Finally, we present the auxiliary role of YidC as a chaperone for inner-membrane proteins. We show how biophysical approaches provide new insights into the dynamics of membrane protein biogenesis and raise new questions as to how translation modulates protein folding.
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42
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Bense S, Witte J, Preuße M, Koska M, Pezoldt L, Dröge A, Hartmann O, Müsken M, Schulze J, Fiebig T, Bähre H, Felgner S, Pich A, Häussler S. Pseudomonas aeruginosa post-translational responses to elevated c-di-GMP levels. Mol Microbiol 2022; 117:1213-1226. [PMID: 35362616 DOI: 10.1111/mmi.14902] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 03/22/2022] [Accepted: 03/27/2022] [Indexed: 11/29/2022]
Abstract
C-di-GMP signaling can directly influence bacterial behavior by affecting the functionality of c-di-GMP-binding proteins. In addition, c-di-GMP can exert a global effect on gene transcription or translation, e.g., via riboswitches or by binding to transcription factors. In this study, we investigated the effects of changes in intracellular c-di-GMP levels on gene expression and protein production in the opportunistic pathogen Pseudomonas aeruginosa. We induced c-di-GMP production via an ectopically introduced diguanylate cyclase and recorded the transcriptional, translational as well as proteomic profile of the cells. We demonstrate that rising levels of c-di-GMP under growth conditions otherwise characterized by low c-di-GMP levels caused a switch to a non-motile, auto-aggregative P. aeruginosa phenotype. This phenotypic switch became apparent before any c-di-GMP-dependent role on transcription, translation, or protein abundance was observed. Our results suggest that rising global c-di-GMP pools first affects the motility phenotype of P. aeruginosa by altering protein functionality and only then global gene transcription.
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Affiliation(s)
- Sarina Bense
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany
| | - Julius Witte
- Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany.,Research Core Unit Proteomics and Institute for Toxicology, Hannover Medical School, Hannover, Germany
| | - Matthias Preuße
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Michal Koska
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany
| | - Lorena Pezoldt
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany
| | - Astrid Dröge
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Oliver Hartmann
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany
| | - Mathias Müsken
- Central Facility for Microscopy, Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Julia Schulze
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Heike Bähre
- Research Core Unit Metabolomics and Institute of Pharmacology, Hannover Medical School, Hannover, Germany. Infection Research, Hannover, Germany
| | - Sebastian Felgner
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany
| | - Andreas Pich
- Research Core Unit Proteomics and Institute for Toxicology, Hannover Medical School, Hannover, Germany
| | - Susanne Häussler
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, Braunschweig, Germany.,Institute for Molecular Bacteriology, TWINCORE GmbH, Center of Clinical and Experimental Infection Research, a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover, Germany.,Department of Clinical Microbiology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
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43
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Protein folding in vitro and in the cell: From a solitary journey to a team effort. Biophys Chem 2022; 287:106821. [PMID: 35667131 PMCID: PMC9636488 DOI: 10.1016/j.bpc.2022.106821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/18/2022] [Accepted: 04/21/2022] [Indexed: 12/22/2022]
Abstract
Correct protein folding is essential for the health and function of living organisms. Yet, it is not well understood how unfolded proteins reach their native state and avoid aggregation, especially within the cellular milieu. Some proteins, especially small, single-domain and apparent two-state folders, successfully attain their native state upon dilution from denaturant. Yet, many more proteins undergo misfolding and aggregation during this process, in a concentration-dependent fashion. Once formed, native and aggregated states are often kinetically trapped relative to each other. Hence, the early stages of protein life are absolutely critical for proper kinetic channeling to the folded state and for long-term solubility and function. This review summarizes current knowledge on protein folding/aggregation mechanisms in buffered solution and within the bacterial cell, highlighting early stages. Remarkably, teamwork between nascent chain, ribosome, trigger factor and Hsp70 molecular chaperones enables all proteins to overcome aggregation propensities and reach a long-lived bioactive state.
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44
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Matavacas J, von Wachenfeldt C. Update on the Protein Homeostasis Network in Bacillus subtilis. Front Microbiol 2022; 13:865141. [PMID: 35350626 PMCID: PMC8957991 DOI: 10.3389/fmicb.2022.865141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Protein homeostasis is fundamental to cell function and survival. It relies on an interconnected network of processes involving protein synthesis, folding, post-translational modification and degradation as well as regulators of these processes. Here we provide an update on the roles, regulation and subcellular localization of the protein homeostasis machinery in the Gram-positive model organism Bacillus subtilis. We discuss emerging ideas and current research gaps in the field that, if tackled, increase our understanding of how Gram-positive bacteria, including several human pathogens, maintain protein homeostasis and cope with stressful conditions that challenge their survival.
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45
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Smith C, Canestrari JG, Wang AJ, Champion MM, Derbyshire KM, Gray TA, Wade JT. Pervasive translation in Mycobacterium tuberculosis. eLife 2022; 11:e73980. [PMID: 35343439 PMCID: PMC9094748 DOI: 10.7554/elife.73980] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 03/25/2022] [Indexed: 11/13/2022] Open
Abstract
Most bacterial ORFs are identified by automated prediction algorithms. However, these algorithms often fail to identify ORFs lacking canonical features such as a length of >50 codons or the presence of an upstream Shine-Dalgarno sequence. Here, we use ribosome profiling approaches to identify actively translated ORFs in Mycobacterium tuberculosis. Most of the ORFs we identify have not been previously described, indicating that the M. tuberculosis transcriptome is pervasively translated. The newly described ORFs are predominantly short, with many encoding proteins of ≤50 amino acids. Codon usage of the newly discovered ORFs suggests that most have not been subject to purifying selection, and hence are unlikely to contribute to cell fitness. Nevertheless, we identify 90 new ORFs (median length of 52 codons) that bear the hallmarks of purifying selection. Thus, our data suggest that pervasive translation of short ORFs in Mycobacterium tuberculosis serves as a rich source for the evolution of new functional proteins.
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Affiliation(s)
- Carol Smith
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
| | - Jill G Canestrari
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
| | - Archer J Wang
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
| | - Matthew M Champion
- Department of Chemistry and Biochemistry, University of Notre DameNotre DameUnited States
| | - Keith M Derbyshire
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
- Department of Biomedical Sciences, School of Public Health, University at AlbanyNew YorkUnited States
| | - Todd A Gray
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
- Department of Biomedical Sciences, School of Public Health, University at AlbanyNew YorkUnited States
| | - Joseph T Wade
- Wadsworth Center, Division of Genetics, New York State Department of HealthAlbanyUnited States
- Department of Biomedical Sciences, School of Public Health, University at AlbanyNew YorkUnited States
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46
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Fujita T, Yokoyama T, Shirouzu M, Taguchi H, Ito T, Iwasaki S. The landscape of translational stall sites in bacteria revealed by monosome and disome profiling. RNA (NEW YORK, N.Y.) 2022; 28:290-302. [PMID: 34906996 PMCID: PMC8848927 DOI: 10.1261/rna.078188.120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 11/24/2021] [Indexed: 05/29/2023]
Abstract
Ribosome pauses are associated with various cotranslational events and determine the fate of mRNAs and proteins. Thus, the identification of precise pause sites across the transcriptome is desirable; however, the landscape of ribosome pauses in bacteria remains ambiguous. Here, we harness monosome and disome (or collided ribosome) profiling strategies to survey ribosome pause sites in Escherichia coli Compared to eukaryotes, ribosome collisions in bacteria showed remarkable differences: a low frequency of disomes at stop codons, collisions occurring immediately after 70S assembly on start codons, and shorter queues of ribosomes trailing upstream. The pause sites corresponded with the biochemical validation by integrated nascent chain profiling (iNP) to detect polypeptidyl-tRNA, an elongation intermediate. Moreover, the subset of those sites showed puromycin resistance, presenting slow peptidyl transfer. Among the identified sites, the ribosome pause at Asn586 of ycbZ was validated by biochemical reporter assay, tRNA sequencing (tRNA-seq), and cryo-electron microscopy (cryo-EM) experiments. Our results provide a useful resource for ribosome stalling sites in bacteria.
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Affiliation(s)
- Tomoya Fujita
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198 Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503, Japan
| | - Takeshi Yokoyama
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Mikako Shirouzu
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Hideki Taguchi
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503, Japan
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Midori-ku, Yokohama 226-8503, Japan
| | - Takuhiro Ito
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Shintaro Iwasaki
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198 Japan
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
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47
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Yang CI, Kim J, Shan SO. Ribosome-nascent chain interaction regulates N-terminal protein modification. J Mol Biol 2022; 434:167535. [PMID: 35278477 PMCID: PMC9126151 DOI: 10.1016/j.jmb.2022.167535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/01/2022] [Accepted: 03/04/2022] [Indexed: 01/02/2023]
Abstract
Numerous proteins initiate their folding, localization, and modifications early during translation, and emerging data show that the ribosome actively participates in diverse protein biogenesis pathways. Here we show that the ribosome imposes an additional layer of substrate selection during N-terminal methionine excision (NME), an essential protein modification in bacteria. Biochemical analyses show that cotranslational NME is exquisitely sensitive to a hydrophobic signal sequence or transmembrane domain near the N terminus of the nascent polypeptide. The ability of the nascent chain to access the active site of NME enzymes dictates NME efficiency, which is inhibited by confinement of the nascent chain on the ribosome surface and exacerbated by signal recognition particle. In vivo measurements corroborate the inhibition of NME by an N-terminal hydrophobic sequence, suggesting the retention of formylmethionine on a substantial fraction of the secretory and membrane proteome. Our work demonstrates how molecular features of a protein regulate its cotranslational modification and highlights the active participation of the ribosome in protein biogenesis pathways via interactions of the ribosome surface with the nascent protein.
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48
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Synergistic Regulation of Transcription and Translation in Escherichia coli Revealed by Codirectional Increases in mRNA Concentration and Translation Efficiency. Microbiol Spectr 2022; 10:e0204121. [PMID: 35138139 PMCID: PMC8826937 DOI: 10.1128/spectrum.02041-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Translational regulation was investigated at the genome-scale in Escherichia coli cells. Using the polysome profiling method, the ribosome occupancy (RO) and ribosome density (RD) of different mRNA copies were determined for several hundred mRNAs during the exponential- and stationary-phases, providing the most complete characterization of such regulation in E. coli. Although for most genes, nearly all mRNAs (>90%) were undergoing translation, they were loaded with far fewer than the theoretical maximum number of ribosomes, suggesting translation limitation at the initiation step. Multiple linear regression was used to identify key intrinsic factors involved in the genome-wide regulation of RO and RD (i.e., open reading frame GC%, protein function, and localization). Unexpectedly, mRNA concentration, a factor that depends on cell physiology, was predicted to positively regulate RO and RD during the exponential- and stationary-phases. Using a set of selected genes controlled by an inducible promoter, we confirmed that increasing the mRNA concentration upon transcription induction led to increases in both RO and ribosome load. The fact that this relationship between mRNA concentration and translation parameters was also effective when E. coli cells naturally adapted to carbon source changes demonstrates its physiological relevance. This work demonstrated that translation regulation is positively controlled by transcript availability. This new mechanism contributed to the codirectional regulation of transcription and translation with synergistic effects on gene expression and provided a systemic understanding of E. coli cell function. IMPORTANCE The process of gene expression is divided into translation and transcription. Considerable efforts have been made in bacteria to characterize the mechanisms underlying translational regulation and identify the regulatory factors for particular mRNAs. However, to understand bacterial physiology and adaptation, it is important to elucidate genome-wide translational regulation and examine its coordination with transcriptional regulation. Here, we provided a genome-wide picture of translational regulation in Escherichia coli. For most genes, nearly all mRNA copies were found to undergo translation but were loaded with a low number of ribosomes. We showed that mRNA concentration had a positive effect on translation regulation, linking translational regulation to transcriptional regulation as well as to cell physiology and growth conditions. The codirectional regulation of transcription and translation had synergistic effects on gene expression, contributing to E. coli cell function optimization. This finding could be used in biotechnology to optimize strategies for recombinant protein synthesis.
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49
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Vazquez-Laslop N, Sharma CM, Mankin A, Buskirk AR. Identifying Small Open Reading Frames in Prokaryotes with Ribosome Profiling. J Bacteriol 2022; 204:e0029421. [PMID: 34339296 PMCID: PMC8765392 DOI: 10.1128/jb.00294-21] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Small proteins encoded by open reading frames (ORFs) shorter than 50 codons (small ORFs [sORFs]) are often overlooked by annotation engines and are difficult to characterize using traditional biochemical techniques. Ribosome profiling has tremendous potential to empirically improve the annotations of prokaryotic genomes. Recent improvements in ribosome profiling methods for bacterial model organisms have revealed many new sORFs in well-characterized genomes. Antibiotics that trap ribosomes just after initiation have played a key role in these developments by allowing the unambiguous identification of the start codons (and, hence, the reading frame) for novel ORFs. Here, we describe these new methods and highlight critical controls and considerations for adapting ribosome profiling to different prokaryotic species.
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Affiliation(s)
- Nora Vazquez-Laslop
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Cynthia M. Sharma
- Molecular Infection Biology II, Institute of Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Alexander Mankin
- Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Allen R. Buskirk
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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50
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Gelhausen R, Müller T, Svensson SL, Alkhnbashi OS, Sharma CM, Eggenhofer F, Backofen R. RiboReport - benchmarking tools for ribosome profiling-based identification of open reading frames in bacteria. Brief Bioinform 2022; 23:6509045. [PMID: 35037022 PMCID: PMC8921622 DOI: 10.1093/bib/bbab549] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 11/22/2021] [Accepted: 11/29/2021] [Indexed: 11/19/2022] Open
Abstract
Small proteins encoded by short open reading frames (ORFs) with 50 codons or fewer are emerging as an important class of cellular macromolecules in diverse organisms. However, they often evade detection by proteomics or in silico methods. Ribosome profiling (Ribo-seq) has revealed widespread translation in genomic regions previously thought to be non-coding, driving the development of ORF detection tools using Ribo-seq data. However, only a handful of tools have been designed for bacteria, and these have not yet been systematically compared. Here, we aimed to identify tools that use Ribo-seq data to correctly determine the translational status of annotated bacterial ORFs and also discover novel translated regions with high sensitivity. To this end, we generated a large set of annotated ORFs from four diverse bacterial organisms, manually labeled for their translation status based on Ribo-seq data, which are available for future benchmarking studies. This set was used to investigate the predictive performance of seven Ribo-seq-based ORF detection tools (REPARATION_blast, DeepRibo, Ribo-TISH, PRICE, smORFer, ribotricer and SPECtre), as well as IRSOM, which uses coding potential and RNA-seq coverage only. DeepRibo and REPARATION_blast robustly predicted translated ORFs, including sORFs, with no significant difference for ORFs in close proximity to other genes versus stand-alone genes. However, no tool predicted a set of novel, experimentally verified sORFs with high sensitivity. Start codon predictions with smORFer show the value of initiation site profiling data to further improve the sensitivity of ORF prediction tools in bacteria. Overall, we find that bacterial tools perform well for sORF detection, although there is potential for improving their performance, applicability, usability and reproducibility.
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Affiliation(s)
- Rick Gelhausen
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110, Freiburg, Germany
| | - Teresa Müller
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110, Freiburg, Germany
| | - Sarah L Svensson
- Department of Molecular Infection Biology II, Institute of Molecular Infection Biology (IMIB), University of Würzburg, Josef-Schneider-Str. 2 / D15, 97080, Würzburg, Germany
| | - Omer S Alkhnbashi
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110, Freiburg, Germany
| | - Cynthia M Sharma
- Department of Molecular Infection Biology II, Institute of Molecular Infection Biology (IMIB), University of Würzburg, Josef-Schneider-Str. 2 / D15, 97080, Würzburg, Germany
| | - Florian Eggenhofer
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110, Freiburg, Germany
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Georges-Köhler-Allee 106, 79110, Freiburg, Germany.,Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Schänzlestr. 18, 79104, State, Germany
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