1
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Litberg TJ, Horowitz S. Roles of Nucleic Acids in Protein Folding, Aggregation, and Disease. ACS Chem Biol 2024; 19:809-823. [PMID: 38477936 PMCID: PMC11149768 DOI: 10.1021/acschembio.3c00695] [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] [Indexed: 03/14/2024]
Abstract
The role of nucleic acids in protein folding and aggregation is an area of continued research, with relevance to understanding both basic biological processes and disease. In this review, we provide an overview of the trajectory of research on both nucleic acids as chaperones and their roles in several protein misfolding diseases. We highlight key questions that remain on the biophysical and biochemical specifics of how nucleic acids have large effects on multiple proteins' folding and aggregation behavior and how this pertains to multiple protein misfolding diseases.
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Affiliation(s)
- Theodore J Litberg
- Department of Chemistry & Biochemistry and The Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado 80208, United States
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Scott Horowitz
- Department of Chemistry & Biochemistry and The Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado 80208, United States
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2
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Leone S, Srivastava A, Herrero-Ruiz A, Hummel B, Tittel L, Campalastri R, Aprile-Garcia F, Tan JH, Rawat P, Andersson P, Willis AE, Sawarkar R. HSP70 binds to specific non-coding RNA and regulates human RNA polymerase III. Mol Cell 2024; 84:687-701.e7. [PMID: 38266641 DOI: 10.1016/j.molcel.2024.01.001] [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: 02/18/2022] [Revised: 10/20/2023] [Accepted: 01/02/2024] [Indexed: 01/26/2024]
Abstract
Molecular chaperones are critical for protein homeostasis and are implicated in several human pathologies such as neurodegeneration and cancer. While the binding of chaperones to nascent and misfolded proteins has been studied in great detail, the direct interaction between chaperones and RNA has not been systematically investigated. Here, we provide the evidence for widespread interaction between chaperones and RNA in human cells. We show that the major chaperone heat shock protein 70 (HSP70) binds to non-coding RNA transcribed by RNA polymerase III (RNA Pol III) such as tRNA and 5S rRNA. Global chromatin profiling revealed that HSP70 binds genomic sites of transcription by RNA Pol III. Detailed biochemical analyses showed that HSP70 alleviates the inhibitory effect of cognate tRNA transcript on tRNA gene transcription. Thus, our study uncovers an unexpected role of HSP70-RNA interaction in the biogenesis of a specific class of non-coding RNA with wider implications in cancer therapeutics.
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Affiliation(s)
- Sergio Leone
- MRC Toxicology Unit, University of Cambridge, Cambridge CB21QR, UK.
| | | | | | - Barbara Hummel
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg 79108, Germany
| | - Lena Tittel
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg 79108, Germany
| | | | | | - Jun Hao Tan
- MRC Toxicology Unit, University of Cambridge, Cambridge CB21QR, UK
| | - Prashant Rawat
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg 79108, Germany
| | - Patrik Andersson
- Safety Innovation, Clinical Pharmacology and Safety Sciences, AstraZeneca R&D, Gothenburg 43183, Sweden
| | - Anne E Willis
- MRC Toxicology Unit, University of Cambridge, Cambridge CB21QR, UK
| | - Ritwick Sawarkar
- MRC Toxicology Unit, University of Cambridge, Cambridge CB21QR, UK; Max Planck Institute of Immunobiology and Epigenetics, Freiburg 79108, Germany.
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3
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Park C, Han B, Choi Y, Jin Y, Kim KP, Choi SI, Seong BL. RNA-dependent proteome solubility maintenance in Escherichia coli lysates analysed by quantitative mass spectrometry: Proteomic characterization in terms of isoelectric point, structural disorder, functional hub, and chaperone network. RNA Biol 2024; 21:1-18. [PMID: 38361426 PMCID: PMC10878026 DOI: 10.1080/15476286.2024.2315383] [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] [Accepted: 02/02/2024] [Indexed: 02/17/2024] Open
Abstract
Protein aggregation, a consequence of misfolding and impaired proteostasis, can lead to cellular malfunctions such as various proteinopathies. The mechanisms protecting proteins from aggregation in complex cellular environments have long been investigated, often from a protein-centric viewpoint. However, our study provides insights into a crucial, yet overlooked actor: RNA. We found that depleting RNAs from Escherichia coli lysates induces global protein aggregation. Our quantitative mass spectrometry analysis identified over 900 statistically significant proteins from the Escherichia coli proteome whose solubility depends on RNAs. Proteome-wide characterization showed that the RNA dependency is particularly enriched among acidic proteins, intrinsically disordered proteins, and structural hub proteins. Moreover, we observed distinct differences in RNA-binding mode and Gene Ontology categories between RNA-dependent acidic and basic proteins. Notably, the solubility of key molecular chaperones [Trigger factor, DnaJ, and GroES] is largely dependent on RNAs, suggesting a yet-to-be-explored hierarchical relationship between RNA-based chaperone (termed as chaperna) and protein-based chaperones, both of which constitute the whole chaperone network. These findings provide new insights into the RNA-centric role in maintaining healthy proteome solubility in vivo, where proteins associate with a variety of RNAs, either stably or transiently.
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Affiliation(s)
- Chan Park
- Department of Microbiology, College of Medicine, Yonsei University, Seoul, Korea
- Vaccine Innovative Technology ALliance (VITAL)-Korea, Yonsei University, Seoul, Korea
| | - Bitnara Han
- Department of Applied Chemistry, Institute of Natural Science, Global Center for Pharmaceutical Ingredient Materials, Kyung Hee University, Yongin, Korea
| | - Yura Choi
- Vaccine Innovative Technology ALliance (VITAL)-Korea, Yonsei University, Seoul, Korea
- The Interdisciplinary Graduate Program in Integrative Biotechnology and Translational Medicine, Yonsei University, Incheon, Korea
| | - Yoontae Jin
- Vaccine Innovative Technology ALliance (VITAL)-Korea, Yonsei University, Seoul, Korea
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, Korea
| | - Kwang Pyo Kim
- Department of Applied Chemistry, Institute of Natural Science, Global Center for Pharmaceutical Ingredient Materials, Kyung Hee University, Yongin, Korea
- Department of Biomedical Science and Technology, Kyung Hee Medical Science Research Institute, Kyung Hee University, Seoul, Republic of Korea
| | - Seong Il Choi
- Department of Pediatrics, Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea
| | - Baik L. Seong
- Department of Microbiology, College of Medicine, Yonsei University, Seoul, Korea
- Vaccine Innovative Technology ALliance (VITAL)-Korea, Yonsei University, Seoul, Korea
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4
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Guzman BB, Son A, Litberg TJ, Huang Z, Dominguez D, Horowitz S. Emerging roles for G-quadruplexes in proteostasis. FEBS J 2023; 290:4614-4625. [PMID: 36017725 PMCID: PMC10071977 DOI: 10.1111/febs.16608] [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: 04/05/2022] [Revised: 07/22/2022] [Accepted: 08/25/2022] [Indexed: 11/29/2022]
Abstract
How nucleic acids interact with proteins, and how they affect protein folding, aggregation, and misfolding is a still-evolving area of research. Considerable effort is now focusing on a particular structure of RNA and DNA, G-quadruplexes, and their role in protein homeostasis and disease. In this state-of-the-art review, we track recent reports on how G-quadruplexes influence protein aggregation, proteolysis, phase separation, and protein misfolding diseases, and pose currently unanswered questions in the advance of this scientific field.
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Affiliation(s)
- Bryan B Guzman
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ahyun Son
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Theodore J Litberg
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Zijue Huang
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Daniel Dominguez
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
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5
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Ham S, Lee C. Exploring the impact of nucleic acids on protein stability in bacterial cell lysate. Biochim Biophys Acta Gen Subj 2023; 1867:130445. [PMID: 37591417 DOI: 10.1016/j.bbagen.2023.130445] [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: 04/24/2023] [Revised: 08/02/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023]
Abstract
- Addition of salt enhanced thermal stability of model substrate proteins by reducing electrostatic repulsion between protein molecules. - However, the opposite effect was observed with bacterial cell lysate, indicating that certain molecules within the lysate could enhance protein stability via electrostatic interactions. - Such molecules present in cell lysate were found to be nucleic acids known to have a potent anti-aggregation activity toward proteins involving electrostatic interactions. - Nucleic acids showed chaperone activity in physiological salt concentration within cells and in buffer or medium commonly used in experiments. - The chaperone activity of nucleic acids should be taken into account when performing various in vitro assays using cell lysate or samples containing nucleic acids.
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Affiliation(s)
- Soojeong Ham
- Department of Biological Sciences, Ajou University, Suwon, South Korea
| | - Changhan Lee
- Department of Biological Sciences, Ajou University, Suwon, South Korea.
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6
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Son A, Huizar Cabral V, Huang Z, Litberg TJ, Horowitz S. G-quadruplexes rescuing protein folding. Proc Natl Acad Sci U S A 2023; 120:e2216308120. [PMID: 37155907 PMCID: PMC10194009 DOI: 10.1073/pnas.2216308120] [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: 09/23/2022] [Accepted: 04/12/2023] [Indexed: 05/10/2023] Open
Abstract
Maintaining the health of the proteome is a critical cellular task. Recently, we found G-quadruplex (G4) nucleic acids are especially potent at preventing protein aggregation in vitro and could at least indirectly improve the protein folding environment of Escherichia coli. However, the roles of G4s in protein folding were not yet explored. Here, through in vitro protein folding experiments, we discover that G4s can accelerate protein folding by rescuing kinetically trapped intermediates to both native and near-native folded states. Time-course folding experiments in E. coli further demonstrate that these G4s primarily improve protein folding quality in E. coli as opposed to preventing protein aggregation. The ability of a short nucleic acid to rescue protein folding opens up the possibility of nucleic acids and ATP-independent chaperones to play considerable roles in dictating the ultimate folding fate of proteins.
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Affiliation(s)
- Ahyun Son
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO80208
| | - Veronica Huizar Cabral
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO80208
| | - Zijue Huang
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO80208
| | - Theodore J. Litberg
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO80208
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO80208
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7
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Substoichiometric action of long noncoding RNAs. Nat Cell Biol 2022; 24:608-615. [PMID: 35562482 DOI: 10.1038/s41556-022-00911-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 04/01/2022] [Indexed: 11/08/2022]
Abstract
Low expression levels and stoichiometric imbalances of long noncoding RNAs (lncRNAs) are often used as evidence for their probable lack of function or for limiting the scope of their potential influence. Recent advances in our understanding of the substoichiometric functions of lncRNAs challenge these notions and suggest routes through which unabundant lncRNAs can affect cellular functions and gene regulatory networks.
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8
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Bevilacqua PC, Williams AM, Chou HL, Assmann SM. RNA multimerization as an organizing force for liquid-liquid phase separation. RNA (NEW YORK, N.Y.) 2022; 28:16-26. [PMID: 34706977 PMCID: PMC8675289 DOI: 10.1261/rna.078999.121] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
RNA interactions are exceptionally strong and highly redundant. As such, nearly any two RNAs have the potential to interact with one another over relatively short stretches, especially at high RNA concentrations. This is especially true for pairs of RNAs that do not form strong self-structure. Such phenomena can drive liquid-liquid phase separation, either solely from RNA-RNA interactions in the presence of divalent or organic cations, or in concert with proteins. RNA interactions can drive multimerization of RNA strands via both base-pairing and tertiary interactions. In this article, we explore the tendency of RNA to form stable monomers, dimers, and higher order structures as a function of RNA length and sequence through a focus on the intrinsic thermodynamic, kinetic, and structural properties of RNA. The principles we discuss are independent of any specific type of biomolecular condensate, and thus widely applicable. We also speculate how external conditions experienced by living organisms can influence the formation of nonmembranous compartments, again focusing on the physical and structural properties of RNA. Plants, in particular, are subject to diverse abiotic stresses including extreme temperatures, drought, and salinity. These stresses and the cellular responses to them, including changes in the concentrations of small molecules such as polyamines, salts, and compatible solutes, have the potential to regulate condensate formation by melting or strengthening base-pairing. Reversible condensate formation, perhaps including regulation by circadian rhythms, could impact biological processes in plants, and other organisms.
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Affiliation(s)
- Philip C Bevilacqua
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biochemistry, Microbiology, and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Allison M Williams
- Department of Biochemistry, Microbiology, and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Hong-Li Chou
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Sarah M Assmann
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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9
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Ren C, Zheng Y, Liu C, Mencius J, Wu Z, Quan S. Molecular Characterization of an Intrinsically Disordered Chaperone Reveals Net-Charge Regulation in Chaperone Action. J Mol Biol 2021; 434:167405. [PMID: 34914967 DOI: 10.1016/j.jmb.2021.167405] [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: 08/13/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/18/2022]
Abstract
Molecular chaperones are diverse biomacromolecules involved in the maintenance of cellular protein homeostasis (proteostasis). Here we demonstrate that in contrast to most chaperones with defined three-dimensional structures, the acid-inducible protein Asr in Escherichia coli is intrinsically disordered and exhibits varied aggregation-preventing or aggregation-promoting activities, acting as a "conditionally active chaperone". Bioinformatics and experimental analyses of Asr showed that it is devoid of hydrophobic patches but rich in positive charges and local polyproline II backbone structures. Asr contributes to the integrity of the bacterial outer membrane under mildly acidic conditions in vivo and possesses chaperone activities toward model clients in vitro. Notably, its chaperone activity is dependent on the net charges of clients: on the one hand, it inhibits the aggregation of clients with similar net charges; on the other hand, it stimulates the aggregation of clients with opposite net charges. Mutational analysis confirmed that positively charged residues in Asr are essential for the varied effects on protein aggregation, suggesting that electrostatic interactions are the major driving forces underlying Asr's proteostasis-related activity. These findings present a unique example of an intrinsically disordered molecular chaperone with distinctive dual functions-as an aggregase or as a chaperone-depending on the net charges of clients.
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Affiliation(s)
- Chang Ren
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Yongxin Zheng
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Chunlan Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Jun Mencius
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Zhili Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China
| | - Shu Quan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), Shanghai 200237, China; Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Shanghai 200237, China.
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10
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Hwang BJ, Jang Y, Kwon SB, Yu JE, Lim J, Roh YH, Seong BL. RNA-assisted self-assembly of monomeric antigens into virus-like particles as a recombinant vaccine platform. Biomaterials 2021; 269:120650. [PMID: 33465537 DOI: 10.1016/j.biomaterials.2021.120650] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 12/15/2020] [Accepted: 12/30/2020] [Indexed: 12/11/2022]
Abstract
Representing highly ordered repetitive structures of antigen macromolecular assemblies, virus-like particles (VLPs) serve as a high-priority vaccine platform against emerging viral infections, as alternatives to traditional cell culture-based vaccines. RNAs can function as chaperones (Chaperna) and are extremely effective in promoting protein folding. Beyond their canonical function as translational adaptors, tRNAs may moonlight as chaperones for the kinetic control of macromolecular antigen assembly. Capitalizing on genomic RNA co-assembly in infectious virions, we present the first report of a biomimetic assembly of viral capsids that was assisted by non-viral host RNAs into genome-free, non-infectious empty particles. Here, we demonstrate the assembly of bacterially-produced soluble norovirus VP1 forming VLPs (n = 180) in vitro. A tRNA-interacting domain (tRID) was genetically fused with the VP1 capsid protein, as a tRNA docking tag, in the bacterial host to transduce chaperna function for de novo viral antigen folding. tRID/tRNA removal prompted the in vitro assembly of monomeric antigens into highly ordered repetitive structures that elicited robust protective immune responses after immunization. The chaperna-based assembly of monomeric antigens will impact the development and deployment of VLP vaccines for emerging and re-emerging viral infections.
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Affiliation(s)
- Beom Jeung Hwang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea; Vaccine Innovative Technology Alliance-Korea, Yonsei University, Seoul, 03722, Republic of Korea
| | - Yohan Jang
- Department of Biological Sciences and Biotechnology Major in Bio-Vaccine Engineering, Andong National University, Andong, South Korea
| | - Soon Bin Kwon
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Ji Eun Yu
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Jongkwan Lim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Young Hoon Roh
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
| | - Baik L Seong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea; Vaccine Innovative Technology Alliance-Korea, Yonsei University, Seoul, 03722, Republic of Korea.
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11
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Louka A, Zacco E, Temussi PA, Tartaglia GG, Pastore A. RNA as the stone guest of protein aggregation. Nucleic Acids Res 2020; 48:11880-11889. [PMID: 33068411 PMCID: PMC7708036 DOI: 10.1093/nar/gkaa822] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/12/2020] [Accepted: 10/14/2020] [Indexed: 12/13/2022] Open
Abstract
The study of prions as infectious aggregates dates several decades. From its original formulation, the definition of a prion has progressively changed to the point that many aggregation-prone proteins are now considered bona fide prions. RNA molecules, not included in the original 'protein-only hypothesis', are also being recognized as important factors contributing to the 'prion behaviour', that implies the transmissibility of an aberrant fold. In particular, an association has recently emerged between aggregation and the assembly of prion-like proteins in RNA-rich complexes, associated with both physiological and pathological events. Here, we discuss the historical rising of the concept of prion-like domains, their relation to RNA and their role in protein aggregation. As a paradigmatic example, we present the case study of TDP-43, an RNA-binding prion-like protein associated with amyotrophic lateral sclerosis. Through this example, we demonstrate how the current definition of prions has incorporated quite different concepts making the meaning of the term richer and more stimulating. An important message that emerges from our analysis is the dual role of RNA in protein aggregation, making RNA, that has been considered for many years a 'silent presence' or the 'stone guest' of protein aggregation, an important component of the process.
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Affiliation(s)
- Alexandra Louka
- UK Dementia Research Institute at the Maurice Wohl Institute of King's College London, London SE5 9RT, UK
| | - Elsa Zacco
- Center for Human Technologies, Central RNA laboratory, Istituto Italiano di Tecnologia, Genova 16152, Italy
| | - Piero Andrea Temussi
- UK Dementia Research Institute at the Maurice Wohl Institute of King's College London, London SE5 9RT, UK
- University “Federico II’’ Napoli, via Cynthia, Napoli 80100, Italy
| | - Gian Gaetano Tartaglia
- Center for Human Technologies, Central RNA laboratory, Istituto Italiano di Tecnologia, Genova 16152, Italy
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona 08003, Spain and ICREA, 23 Passeig Lluıs Companys, Barcelona 08010, Spain
- Charles Darwin department of Biology and Biotechnology, Sapienza University of Rome, Piazzale A. Moro 5, Rome 00185, Italy
| | - Annalisa Pastore
- UK Dementia Research Institute at the Maurice Wohl Institute of King's College London, London SE5 9RT, UK
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12
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Aarum J, Cabrera CP, Jones TA, Rajendran S, Adiutori R, Giovannoni G, Barnes MR, Malaspina A, Sheer D. Enzymatic degradation of RNA causes widespread protein aggregation in cell and tissue lysates. EMBO Rep 2020; 21:e49585. [PMID: 32945072 PMCID: PMC7534620 DOI: 10.15252/embr.201949585] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 06/28/2020] [Accepted: 07/30/2020] [Indexed: 12/12/2022] Open
Abstract
Most proteins in cell and tissue lysates are soluble. We show here that in lysate from human neurons, more than 1,300 proteins are maintained in a soluble and functional state by association with endogenous RNA, as degradation of RNA invariably leads to protein aggregation. The majority of these proteins lack conventional RNA‐binding domains. Using synthetic oligonucleotides, we identify the importance of nucleic acid structure, with single‐stranded pyrimidine‐rich bulges or loops surrounded by double‐stranded regions being particularly efficient in the maintenance of protein solubility. These experiments also identify an apparent one‐to‐one protein‐nucleic acid stoichiometry. Furthermore, we show that protein aggregates isolated from brain tissue from Amyotrophic Lateral Sclerosis patients can be rendered soluble after refolding by both RNA and synthetic oligonucleotides. Together, these findings open new avenues for understanding the mechanism behind protein aggregation and shed light on how certain proteins remain soluble.
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Affiliation(s)
- Johan Aarum
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Claudia P Cabrera
- Barts and The London NIHR Cardiovascular Biomedical Research Centre, William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Tania A Jones
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Shiron Rajendran
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Rocco Adiutori
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Gavin Giovannoni
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Michael R Barnes
- Barts and The London NIHR Cardiovascular Biomedical Research Centre, William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Andrea Malaspina
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
| | - Denise Sheer
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
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13
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Begeman A, Son A, Litberg TJ, Wroblewski TH, Gehring T, Huizar Cabral V, Bourne J, Xuan Z, Horowitz S. G-Quadruplexes act as sequence-dependent protein chaperones. EMBO Rep 2020; 21:e49735. [PMID: 32945124 PMCID: PMC7534610 DOI: 10.15252/embr.201949735] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 07/29/2020] [Accepted: 08/05/2020] [Indexed: 01/06/2023] Open
Abstract
Maintaining proteome health is important for cell survival. Nucleic acids possess the ability to prevent protein aggregation more efficiently than traditional chaperone proteins. In this study, we explore the sequence specificity of the chaperone activity of nucleic acids. Evaluating over 500 nucleic acid sequences' effects on protein aggregation, we show that the holdase chaperone effect of nucleic acids is sequence-dependent. G-Quadruplexes prevent protein aggregation via quadruplex:protein oligomerization. They also increase the folded protein level of a biosensor in E. coli. These observations contextualize recent reports of quadruplexes playing important roles in aggregation-related diseases, such as fragile X and amyotrophic lateral sclerosis (ALS), and provide evidence that nucleic acids have the ability to modulate the folding environment of E. coli.
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Affiliation(s)
- Adam Begeman
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Ahyun Son
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Theodore J Litberg
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Tadeusz H Wroblewski
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Thane Gehring
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Veronica Huizar Cabral
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
| | - Jennifer Bourne
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Zhenyu Xuan
- Department of Biological Sciences, Center for Systems Biology, University of Texas at Dallas, Richardson, TX, USA
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, CO, USA
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14
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Abstract
As a mental framework for the transition of self-replicating biological forms, the RNA world concept stipulates a dual function of RNAs as genetic substance and catalyst. The chaperoning function is found intrinsic to ribozymes involved in protein synthesis and tRNA maturation, enriching the primordial RNA world with proteins of biological relevance. The ribozyme-resident protein folding activity, even before the advent of protein-based molecular chaperone, must have expedited the transition of the RNA world into the present protein theatre.
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Affiliation(s)
- Ahyun Son
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver , Denver, CO, USA
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver , Denver, CO, USA
| | - Baik L Seong
- Department of Biotechnology, College of Bioscience and Biotechnology, Yonsei University , Seoul, Korea.,Vaccine Innovation Technology Alliance (VITAL)-Korea, Yonsei University , Seoul, Korea
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15
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Ferdosh S, Banerjee S, Pathak BK, Sengupta J, Barat C. Hibernating ribosomes exhibit chaperoning activity but can resist unfolded protein-mediated subunit dissociation. FEBS J 2020; 288:1305-1324. [PMID: 32649051 DOI: 10.1111/febs.15479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/24/2020] [Accepted: 07/07/2020] [Indexed: 02/03/2023]
Abstract
Ribosome hibernation is a prominent cellular strategy to modulate protein synthesis during starvation and the stationary phase of bacterial cell growth. Translational suppression involves the formation of either factor-bound inactive 70S monomers or dimeric 100S hibernating ribosomal complexes, the biological significance of which is poorly understood. Here, we demonstrate that the Escherichia coli 70S ribosome associated with stationary phase factors hibernation promoting factor or protein Y or ribosome-associated inhibitor A and the 100S ribosome isolated from both Gram-negative and Gram-positive bacteria are resistant to unfolded protein-mediated subunit dissociation and subsequent degradation by cellular ribonucleases. Considering that the increase in cellular stress is accompanied by accumulation of unfolded proteins, such resistance of hibernating ribosomes towards dissociation might contribute to their maintenance during the stationary phase. Analysis of existing structures provided clues on the mechanism of inhibition of the unfolded protein-mediated disassembly in case of hibernating factor-bound ribosome. Further, the factor-bound 70S and 100S ribosomes can suppress protein aggregation and assist in protein folding. The chaperoning activity of these ribosomes is the first evidence of a potential biological activity of the hibernating ribosome that might be crucial for cell survival under stress conditions.
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Affiliation(s)
- Sehnaz Ferdosh
- Department of Biotechnology, St. Xavier's College, Kolkata, India
| | - Senjuti Banerjee
- Department of Biotechnology, St. Xavier's College, Kolkata, India
| | - Bani K Pathak
- Structural Biology and Bio-Informatics Division, Indian Institute of Chemical Biology (Council of Scientific and Industrial Research), Kolkata, India
| | - Jayati Sengupta
- Structural Biology and Bio-Informatics Division, Indian Institute of Chemical Biology (Council of Scientific and Industrial Research), Kolkata, India
| | - Chandana Barat
- Department of Biotechnology, St. Xavier's College, Kolkata, India
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16
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Bowman JC, Petrov AS, Frenkel-Pinter M, Penev PI, Williams LD. Root of the Tree: The Significance, Evolution, and Origins of the Ribosome. Chem Rev 2020; 120:4848-4878. [PMID: 32374986 DOI: 10.1021/acs.chemrev.9b00742] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The ribosome is an ancient molecular fossil that provides a telescope to the origins of life. Made from RNA and protein, the ribosome translates mRNA to coded protein in all living systems. Universality, economy, centrality and antiquity are ingrained in translation. The translation machinery dominates the set of genes that are shared as orthologues across the tree of life. The lineage of the translation system defines the universal tree of life. The function of a ribosome is to build ribosomes; to accomplish this task, ribosomes make ribosomal proteins, polymerases, enzymes, and signaling proteins. Every coded protein ever produced by life on Earth has passed through the exit tunnel, which is the birth canal of biology. During the root phase of the tree of life, before the last common ancestor of life (LUCA), exit tunnel evolution is dominant and unremitting. Protein folding coevolved with evolution of the exit tunnel. The ribosome shows that protein folding initiated with intrinsic disorder, supported through a short, primitive exit tunnel. Folding progressed to thermodynamically stable β-structures and then to kinetically trapped α-structures. The latter were enabled by a long, mature exit tunnel that partially offset the general thermodynamic tendency of all polypeptides to form β-sheets. RNA chaperoned the evolution of protein folding from the very beginning. The universal common core of the ribosome, with a mass of nearly 2 million Daltons, was finalized by LUCA. The ribosome entered stasis after LUCA and remained in that state for billions of years. Bacterial ribosomes never left stasis. Archaeal ribosomes have remained near stasis, except for the superphylum Asgard, which has accreted rRNA post LUCA. Eukaryotic ribosomes in some lineages appear to be logarithmically accreting rRNA over the last billion years. Ribosomal expansion in Asgard and Eukarya has been incremental and iterative, without substantial remodeling of pre-existing basal structures. The ribosome preserves information on its history.
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Affiliation(s)
- Jessica C Bowman
- Center for the Origins of Life, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Anton S Petrov
- Center for the Origins of Life, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Moran Frenkel-Pinter
- Center for the Origins of Life, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Petar I Penev
- Center for the Origins of Life, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Loren Dean Williams
- Center for the Origins of Life, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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17
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Maguire G, Paler L, Green L, Mella R, Valcarcel M, Villace P. Rescue of degenerating neurons and cells by stem cell released molecules: using a physiological renormalization strategy. Physiol Rep 2020; 7:e14072. [PMID: 31050222 PMCID: PMC6497969 DOI: 10.14814/phy2.14072] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/26/2019] [Accepted: 03/31/2019] [Indexed: 12/13/2022] Open
Abstract
Evidence suggests that adult stem cell types and progenitor cells act collectively in a given tissue to maintain and heal organs, such as muscle, through a release of a multitude of molecules packaged into exosomes from the different cell types. Using this principle for the development of bioinspired therapeutics that induces homeostatic renormalization, here we show that the collection of molecules released from four cell types, including mesenchymal stem cells, fibroblast, neural stem cells, and astrocytes, rescues degenerating neurons and cells. Specifically, oxidative stress induced in a human recombinant TDP‐43‐ or FUS‐tGFP U2OS cell line by exposure to sodium arsenite was shown to be significantly reduced by our collection of molecules using in vitro imaging of FUS and TDP‐43 stress granules. Furthermore, we also show that the collective secretome rescues cortical neurons from glutamate toxicity as evidenced by increased neurite outgrowth, reduced LDH release, and reduced caspase 3/7 activity. These data are the first in a series supporting the development of stem cell‐based exosome systems therapeutics that uses a physiological renormalization strategy to treat neurodegenerative diseases.
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Affiliation(s)
- Greg Maguire
- BioRegenerative Sciences, Inc., San Diego, California.,Auditory Sound Waves, LLC, San Diego, California
| | - Lee Paler
- BioRegenerative Sciences, Inc., San Diego, California.,Auditory Sound Waves, LLC, San Diego, California
| | - Linda Green
- BioRegenerative Sciences, Inc., San Diego, California
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18
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Tsuboyama K, Osaki T, Matsuura-Suzuki E, Kozuka-Hata H, Okada Y, Oyama M, Ikeuchi Y, Iwasaki S, Tomari Y. A widespread family of heat-resistant obscure (Hero) proteins protect against protein instability and aggregation. PLoS Biol 2020; 18:e3000632. [PMID: 32163402 PMCID: PMC7067378 DOI: 10.1371/journal.pbio.3000632] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 02/05/2020] [Indexed: 01/08/2023] Open
Abstract
Proteins are typically denatured and aggregated by heating at near-boiling temperature. Exceptions to this principle include highly disordered and heat-resistant proteins found in extremophiles, which help these organisms tolerate extreme conditions such as drying, freezing, and high salinity. In contrast, the functions of heat-soluble proteins in non-extremophilic organisms including humans remain largely unexplored. Here, we report that heat-resistant obscure (Hero) proteins, which remain soluble after boiling at 95°C, are widespread in Drosophila and humans. Hero proteins are hydrophilic and highly charged, and function to stabilize various "client" proteins, protecting them from denaturation even under stress conditions such as heat shock, desiccation, and exposure to organic solvents. Hero proteins can also block several different types of pathological protein aggregations in cells and in Drosophila strains that model neurodegenerative diseases. Moreover, Hero proteins can extend life span of Drosophila. Our study reveals that organisms naturally use Hero proteins as molecular shields to stabilize protein functions, highlighting their biotechnological and therapeutic potential.
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Affiliation(s)
- Kotaro Tsuboyama
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Laboratory of RNA Function, Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Tatsuya Osaki
- Biomolecular and Cellular Engineering laboratory, Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, Japan
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Eriko Matsuura-Suzuki
- Laboratory of RNA Function, Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
| | - Hiroko Kozuka-Hata
- Medical Proteomics Laboratory, The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan
| | - Yuki Okada
- Laboratory of Pathology and Development, Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Masaaki Oyama
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Medical Proteomics Laboratory, The Institute of Medical Science, The University of Tokyo, Minato-ku, Tokyo, Japan
| | - Yoshiho Ikeuchi
- Biomolecular and Cellular Engineering laboratory, Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, Japan
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Shintaro Iwasaki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
| | - Yukihide Tomari
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
- Laboratory of RNA Function, Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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19
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Dynamic conformational flexibility and molecular interactions of intrinsically disordered proteins. J Biosci 2020. [DOI: 10.1007/s12038-020-0010-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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20
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Bhattarai A, Emerson IA. Dynamic conformational flexibility and molecular interactions of intrinsically disordered proteins. J Biosci 2020; 45:29. [PMID: 32020911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Intrinsically disordered proteins (IDPs) are highly flexible and undergo disorder to order transition upon binding. They are highly abundant in human proteomes and play critical roles in cell signaling and regulatory processes. This review mainly focuses on the dynamics of disordered proteins including their conformational heterogeneity, protein-protein interactions, and the phase transition of biomolecular condensates that are central to various biological functions. Besides, the role of RNA-mediated chaperones in protein folding and stability of IDPs were also discussed. Finally, we explored the dynamic binding interface of IDPs as novel therapeutic targets and the effect of small molecules on their interactions.
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Affiliation(s)
- Anil Bhattarai
- Bioinformatics Programming Laboratory, Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore 632 014, India
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21
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Mizrak A, Morgan DO. Polyanions provide selective control of APC/C interactions with the activator subunit. Nat Commun 2019; 10:5807. [PMID: 31862931 PMCID: PMC6925294 DOI: 10.1038/s41467-019-13864-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 12/04/2019] [Indexed: 01/18/2023] Open
Abstract
Transient interactions between the anaphase-promoting complex/cyclosome (APC/C) and its activator subunit Cdc20 or Cdh1 generate oscillations in ubiquitylation activity necessary to maintain the order of cell cycle events. Activator binds the APC/C with high affinity and exhibits negligible dissociation kinetics in vitro, and it is not clear how the rapid turnover of APC/C-activator complexes is achieved in vivo. Here, we describe a mechanism that controls APC/C-activator interactions based on the availability of substrates. We find that APC/C-activator dissociation is stimulated by abundant cellular polyanions such as nucleic acids and polyphosphate. Polyanions also interfere with substrate ubiquitylation. However, engagement with high-affinity substrate blocks the inhibitory effects of polyanions on activator binding and APC/C activity. We propose that this mechanism amplifies the effects of substrate affinity on APC/C function, stimulating processive ubiquitylation of high-affinity substrates and suppressing ubiquitylation of low-affinity substrates.
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Affiliation(s)
- Arda Mizrak
- Department of Physiology, University of California, San Francisco, CA, 94143, USA
| | - David O Morgan
- Department of Physiology, University of California, San Francisco, CA, 94143, USA.
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22
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Litberg TJ, Docter B, Hughes MP, Bourne J, Horowitz S. DNA Facilitates Oligomerization and Prevents Aggregation via DNA Networks. Biophys J 2019; 118:162-171. [PMID: 31839258 DOI: 10.1016/j.bpj.2019.11.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 10/11/2019] [Accepted: 11/05/2019] [Indexed: 12/12/2022] Open
Abstract
Previous studies have shown that nucleic acids can nucleate protein aggregation in disease-related proteins, but in other cases, they can act as molecular chaperones that prevent protein aggregation, even under extreme conditions. In this study, we describe the link between these two behaviors through a combination of electron microscopy and aggregation kinetics. We find that two different proteins become soluble under harsh conditions through oligomerization with DNA. These DNA/protein oligomers form "networks," which increase the speed of oligomerization. The cases of DNA both increasing and preventing protein aggregation are observed to stem from this enhanced oligomerization. This observation raises interesting questions about the role of nucleic acids in aggregate formation in disease states.
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Affiliation(s)
- Theodore J Litberg
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado
| | - Brianne Docter
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan
| | - Michael P Hughes
- Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, California; Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California; Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, California; Department of Energy, University of California, Los Angeles, Los Angeles, California; Institute for Genomics and Proteomics, University of California, Los Angeles, Los Angeles, California
| | - Jennifer Bourne
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
| | - Scott Horowitz
- Department of Chemistry & Biochemistry, Knoebel Institute for Healthy Aging, University of Denver, Denver, Colorado.
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23
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Walter NG. Biological Pathway Specificity in the Cell-Does Molecular Diversity Matter? Bioessays 2019; 41:e1800244. [PMID: 31245864 PMCID: PMC6684156 DOI: 10.1002/bies.201800244] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 05/09/2019] [Indexed: 01/07/2023]
Abstract
Biology arises from the crowded molecular environment of the cell, rendering it a challenge to understand biological pathways based on the reductionist, low-concentration in vitro conditions generally employed for mechanistic studies. Recent evidence suggests that low-affinity interactions between cellular biopolymers abound, with still poorly defined effects on the complex interaction networks that lead to the emergent properties and plasticity of life. Mass-action considerations are used here to underscore that the sheer number of weak interactions expected from the complex mixture of cellular components significantly shapes biological pathway specificity. In particular, on-pathway-i.e., "functional"-become those interactions thermodynamically and kinetically stable enough to survive the incessant onslaught of the many off-pathway ("nonfunctional") interactions. Consequently, to better understand the molecular biology of the cell a further paradigm shift is needed toward mechanistic experimental and computational approaches that probe intracellular diversity and complexity more directly. Also see the video abstract here https://youtu.be/T19X_zYaBzg.
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24
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Lee HM, Kwon SB, Son A, Kim DH, Kim KH, Lim J, Kwon YG, Kang JS, Lee BK, Byun YH, Seong BL. Stabilization of Intrinsically Disordered DKK2 Protein by Fusion to RNA-Binding Domain. Int J Mol Sci 2019; 20:ijms20112847. [PMID: 31212691 PMCID: PMC6600415 DOI: 10.3390/ijms20112847] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/11/2019] [Accepted: 06/10/2019] [Indexed: 12/26/2022] Open
Abstract
Intrinsic disorders are a common feature of hub proteins in eukaryotic interactomes controlling the signaling pathways. The intrinsically disordered proteins (IDPs) are prone to misfolding, and maintaining their functional stability remains a major challenge in validating their therapeutic potentials. Considering that IDPs are highly enriched in RNA-binding proteins (RBPs), here we reasoned and confirmed that IDPs could be stabilized by fusion to RBPs. Dickkopf2 (DKK2), Wnt antagonist and a prototype IDP, was fused with lysyl-tRNA synthetase (LysRS), with or without the fragment crystallizable (Fc) domain of an immunoglobulin and expressed predominantly as a soluble form from a bacterial host. The functional competence was confirmed by in vitro Wnt signaling reporter and tube formation in human umbilical vein endothelial cells (HUVECs) and in vivo Matrigel plug assay. The removal of LysRS by site-specific protease cleavage prompted the insoluble aggregation, confirming that the linkage to RBP chaperones the functional competence of IDPs. While addressing to DKK2 as a key modulator for cancer and ischemic vascular diseases, our results suggest the use of RBPs as stabilizers of disordered proteinaceous materials for acquiring and maintaining the structural stability and functional competence, which would impact the druggability of a variety of IDPs from human proteome.
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Affiliation(s)
- Hye Min Lee
- Department of Biotechnology, College of Life Sciences and Biotechnology, Yonsei University, Seoul 03722, Korea.
- Vaccine Translational Research Center, Yonsei University, Seoul 03722, Korea.
| | - Soon Bin Kwon
- Department of Biotechnology, College of Life Sciences and Biotechnology, Yonsei University, Seoul 03722, Korea.
- Vaccine Translational Research Center, Yonsei University, Seoul 03722, Korea.
| | - Ahyun Son
- Department of Biotechnology, College of Life Sciences and Biotechnology, Yonsei University, Seoul 03722, Korea.
- Vaccine Translational Research Center, Yonsei University, Seoul 03722, Korea.
| | - Doo Hyun Kim
- Department of Pharmacology, and Center for Cancer Research and Diagnostic Medicine, IBST, School of Medicine, Konkuk University, Seoul 05030, Korea.
| | - Kyun-Hwan Kim
- Department of Pharmacology, and Center for Cancer Research and Diagnostic Medicine, IBST, School of Medicine, Konkuk University, Seoul 05030, Korea.
| | - Jonghyo Lim
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Young-Guen Kwon
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Jin Sun Kang
- ProCell R&D Institute, ProCell Therapeutics, Inc., Ace-Twin Tower II, Guro3-dong, Guro-gu, Seoul 08381, Korea.
| | - Byung Kyu Lee
- ProCell R&D Institute, ProCell Therapeutics, Inc., Ace-Twin Tower II, Guro3-dong, Guro-gu, Seoul 08381, Korea.
| | - Young Ho Byun
- Department of Biotechnology, College of Life Sciences and Biotechnology, Yonsei University, Seoul 03722, Korea.
- Vaccine Translational Research Center, Yonsei University, Seoul 03722, Korea.
| | - Baik L Seong
- Department of Biotechnology, College of Life Sciences and Biotechnology, Yonsei University, Seoul 03722, Korea.
- Vaccine Translational Research Center, Yonsei University, Seoul 03722, Korea.
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25
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Abstract
Cells under stress must adjust their physiology, metabolism, and architecture to adapt to the new conditions. Most importantly, they must down-regulate general gene expression, but at the same time induce synthesis of stress-protective factors, such as molecular chaperones. Here, we investigate how the process of phase separation is used by cells to ensure adaptation to stress. We summarize recent findings and propose that the solubility of important translation factors is specifically affected by changes in physical-chemical parameters such temperature or pH and modulated by intrinsically disordered prion-like domains. These stress-triggered changes in protein solubility induce phase separation into condensates that regulate the activity of the translation factors and promote cellular fitness. Prion-like domains play important roles in this process as environmentally regulated stress sensors and modifier sequences that determine protein solubility and phase behavior. We propose that protein phase separation is an evolutionary conserved feature of proteins that cells harness to regulate adaptive stress responses and ensure survival in extreme environmental conditions.
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26
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Conversion of a soluble protein into a potent chaperone in vivo. Sci Rep 2019; 9:2735. [PMID: 30804538 PMCID: PMC6389997 DOI: 10.1038/s41598-019-39158-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 01/18/2019] [Indexed: 01/31/2023] Open
Abstract
Molecular chaperones play an important role in cellular protein-folding assistance and aggregation inhibition. As a different but complementary model, we previously proposed that, in general, soluble cellular macromolecules with large excluded volume and surface charges exhibit intrinsic chaperone activity to prevent aggregation of their connected polypeptides irrespective of the connection type, thereby contributing to efficient protein folding. As a proof of concept, we here demonstrated that a model recombinant protein with a specific sequence-binding domain robustly exerted chaperone activity toward various proteins harbouring a short recognition tag of 7 residues in Escherichia coli. The chaperone activity of this protein was comparable to that of representative E. coli chaperones in vivo. Furthermore, in vitro refolding experiments confirmed the in vivo results. Our findings reveal that a soluble protein exhibits the intrinsic chaperone activity to prevent off-pathway aggregation of its interacting proteins, leading to more productive folding while allowing them to fold according to their intrinsic folding pathways. This study gives new insights into the plausible chaperoning role of soluble cellular macromolecules in terms of aggregation inhibition and indirect folding assistance.
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27
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Zacco E, Graña-Montes R, Martin SR, de Groot NS, Alfano C, Tartaglia GG, Pastore A. RNA as a key factor in driving or preventing self-assembly of the TAR DNA-binding protein 43. J Mol Biol 2019; 431:1671-1688. [PMID: 30742796 PMCID: PMC6461199 DOI: 10.1016/j.jmb.2019.01.028] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 01/22/2019] [Accepted: 01/24/2019] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis and frontotemporal lobar degeneration are incurable motor neuron diseases associated with muscle weakness, paralysis and respiratory failure. Accumulation of TAR DNA-binding protein 43 (TDP-43) as toxic cytoplasmic inclusions is one of the hallmarks of these pathologies. TDP-43 is an RNA-binding protein responsible for regulating RNA transcription, splicing, transport and translation. Aggregated TDP-43 does not retain its physiological function. Here, we exploit the ability of TDP-43 to bind specific RNA sequences to validate our hypothesis that the native partners of a protein can be used to interfere with its ability to self-assemble into aggregates. We propose that binding of TDP-43 to specific RNA can compete with protein aggregation. This study provides a solid proof of concept to the hypothesis that natural interactions can be exploited to increase protein solubility and could be adopted as a more general rational therapeutic strategy. We found that binding of the RRM domains of TDP-43 to specific RNA competes with protein aggregation. This study provides a solid proof of concept to the hypothesis that natural interactions can be exploited to increase protein solubility. The concept could be adopted as a more general rationale for protein-specific drug design.
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Affiliation(s)
- Elsa Zacco
- UK Dementia Research Institute at King's College London, London, SE5 9RT, United Kingdom; The Wohl Institute at King's College London, London, SE5 9RT, United Kingdom
| | - Ricardo Graña-Montes
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain
| | | | - Natalia Sanchez de Groot
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain
| | | | - Gian Gaetano Tartaglia
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona 08003, Spain; Institutio Catalan de Recerca I Estudis Avancats (ICREA), 23 Passeig Lluıs Companys, 08010 Barcelona, Spain; Department of Biology 'Charles Darwin', Sapienza University of Rome, P.le A. Moro 5, Rome 00185, Italy.
| | - Annalisa Pastore
- UK Dementia Research Institute at King's College London, London, SE5 9RT, United Kingdom; The Wohl Institute at King's College London, London, SE5 9RT, United Kingdom; Scuola Normale Superiore, Piazza dei Cavalieri, Pisa, 56126, Italy.
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28
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Abstract
Polyphosphate (polyP) consists of a linear arrangement of inorganic phosphates and defies its structural simplicity with an astounding number of different activities in the cell. Already well known for its ability to partake in phosphate, calcium, and energy metabolism, polyP recently gained a new functional dimension with the discovery that it serves as a stabilizing scaffold for protein-folding intermediates. In this review, we summarize and discuss the recent studies that have identified polyP not only as a potent protein-like chaperone that protects cells against stress-induced protein aggregation, but also as a robust modifier of amyloidogenic processes that shields neuronal cells from amyloid toxicity. We consider some of the most pressing questions in the field, the obstacles faced, and the potential avenues to take to provide a complete picture about the working mechanism and physiological relevance of this intriguing biopolymer.
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Affiliation(s)
- Lihan Xie
- From the Departments of Molecular, Cellular and Developmental Biology and
| | - Ursula Jakob
- From the Departments of Molecular, Cellular and Developmental Biology and
- Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1085
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29
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Hitachi K, Nakatani M, Takasaki A, Ouchi Y, Uezumi A, Ageta H, Inagaki H, Kurahashi H, Tsuchida K. Myogenin promoter-associated lncRNA Myoparr is essential for myogenic differentiation. EMBO Rep 2019; 20:embr.201847468. [PMID: 30622218 DOI: 10.15252/embr.201847468] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 12/17/2018] [Accepted: 12/19/2018] [Indexed: 12/19/2022] Open
Abstract
Promoter-associated long non-coding RNAs (lncRNAs) regulate the expression of adjacent genes; however, precise roles of these lncRNAs in skeletal muscle remain largely unknown. Here, we characterize a promoter-associated lncRNA, Myoparr, in myogenic differentiation and muscle disorders. Myoparr is expressed from the promoter region of the mouse and human myogenin gene, one of the key myogenic transcription factors. We show that Myoparr is essential both for the specification of myoblasts by activating neighboring myogenin expression and for myoblast cell cycle withdrawal by activating myogenic microRNA expression. Mechanistically, Myoparr interacts with Ddx17, a transcriptional coactivator of MyoD, and regulates the association between Ddx17 and the histone acetyltransferase PCAF Myoparr also promotes skeletal muscle atrophy caused by denervation, and knockdown of Myoparr rescues muscle wasting in mice. Our findings demonstrate that Myoparr is a novel key regulator of muscle development and suggest that Myoparr is a potential therapeutic target for neurogenic atrophy in humans.
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Affiliation(s)
- Keisuke Hitachi
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science (ICMS), Fujita Health University, Toyoake, Japan
| | - Masashi Nakatani
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science (ICMS), Fujita Health University, Toyoake, Japan
| | - Akihiko Takasaki
- Department of Medical Technology, School of Health Sciences, Gifu University of Medical Science, Seki, Japan
| | - Yuya Ouchi
- Genome and Transcriptome Analysis Center, Fujita Health University, Toyoake, Japan
| | - Akiyoshi Uezumi
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science (ICMS), Fujita Health University, Toyoake, Japan
| | - Hiroshi Ageta
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science (ICMS), Fujita Health University, Toyoake, Japan
| | - Hidehito Inagaki
- Genome and Transcriptome Analysis Center, Fujita Health University, Toyoake, Japan
| | - Hiroki Kurahashi
- Genome and Transcriptome Analysis Center, Fujita Health University, Toyoake, Japan
| | - Kunihiro Tsuchida
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science (ICMS), Fujita Health University, Toyoake, Japan
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30
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Lee J, Son A, Kim P, Kwon SB, Yu JE, Han G, Seong BL. RNA‐dependent chaperone (chaperna) as an engineered pro‐region for the folding of recombinant microbial transglutaminase. Biotechnol Bioeng 2019; 116:490-502. [DOI: 10.1002/bit.26879] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/15/2018] [Accepted: 11/22/2018] [Indexed: 12/14/2022]
Affiliation(s)
- Jinhee Lee
- Department of Integrated OMICS for Biomedical Science, College of Life science and BiotechnologyYonsei UniversitySeoul Korea
| | - Ahyun Son
- Department of Integrated OMICS for Biomedical Science, College of Life science and BiotechnologyYonsei UniversitySeoul Korea
- Present affiliation: Department of Chemistry and BiochemistryKnoebel Institute for Healthy AgingUniversity of DenverDenver Colorado
| | - Paul Kim
- Department of Integrated OMICS for Biomedical Science, College of Life science and BiotechnologyYonsei UniversitySeoul Korea
| | - Soon Bin Kwon
- Department of BiotechnologyCollege of Life science and BiotechnologyYonsei UniversitySeoul Korea
| | - Ji Eun Yu
- Department of BiotechnologyCollege of Life science and BiotechnologyYonsei UniversitySeoul Korea
| | - Gyoonhee Han
- Department of Integrated OMICS for Biomedical Science, College of Life science and BiotechnologyYonsei UniversitySeoul Korea
- Department of BiotechnologyCollege of Life science and BiotechnologyYonsei UniversitySeoul Korea
| | - Baik L. Seong
- Department of BiotechnologyCollege of Life science and BiotechnologyYonsei UniversitySeoul Korea
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31
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Stull F, Hipp H, Stockbridge RB, Bardwell JCA. In vivo chloride concentrations surge to proteotoxic levels during acid stress. Nat Chem Biol 2018; 14:1051-1058. [PMID: 30323217 PMCID: PMC6193267 DOI: 10.1038/s41589-018-0143-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 08/29/2018] [Indexed: 11/23/2022]
Abstract
To successfully colonize the intestine, bacteria must survive passage through the stomach. The permeability of the outer membrane renders the periplasm of Gram-negative bacteria vulnerable to stomach acid, which inactivates proteins. Here we report that the semipermeable nature of the outer membrane allows the development of a strong Donnan equilibrium across this barrier at low pH. As a result, when bacteria are exposed to conditions that mimic gastric juice, periplasmic chloride concentrations rise to levels that exceed 0.6 M. At these chloride concentrations, proteins readily aggregate in vitro. The acid sensitivity of strains lacking acid-protective chaperones is enhanced by chloride, suggesting that these chaperones protect periplasmic proteins both from acidification and from the accompanying accumulation of chloride. These results illustrate how organisms have evolved chaperones to respond to the substantial chemical threat imposed by otherwise innocuous chloride concentrations that are amplified to proteotoxic levels by low-pH-induced Donnan equilibrium effects.
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Affiliation(s)
- Frederick Stull
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
| | - Hannah Hipp
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Randy B Stockbridge
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
- Department of Biophysics, University of Michigan, Ann Arbor, MI, USA
| | - James C A Bardwell
- Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
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32
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Kwon SB, Yu JE, Park C, Lee J, Seong BL. Nucleic Acid-Dependent Structural Transition of the Intrinsically Disordered N-Terminal Appended Domain of Human Lysyl-tRNA Synthetase. Int J Mol Sci 2018; 19:ijms19103016. [PMID: 30282926 PMCID: PMC6213541 DOI: 10.3390/ijms19103016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/27/2018] [Accepted: 09/29/2018] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic lysyl-tRNA synthetases (LysRS) have an N-terminal appended tRNA-interaction domain (RID) that is absent in their prokaryotic counterparts. This domain is intrinsically disordered and lacks stable structures. The disorder-to-order transition is induced by tRNA binding and has implications on folding and subsequent assembly into multi-tRNA synthetase complexes. Here, we expressed and purified RID from human LysRS (hRID) in Escherichia coli and performed a detailed mutagenesis of the appended domain. hRID was co-purified with nucleic acids during Ni-affinity purification, and cumulative mutations on critical amino acid residues abolished RNA binding. Furthermore, we identified a structural ensemble between disordered and helical structures in non-RNA-binding mutants and an equilibrium shift for wild-type into the helical conformation upon RNA binding. Since mutations that disrupted RNA binding led to an increase in non-functional soluble aggregates, a stabilized RNA-mediated structural transition of the N-terminal appended domain may have implications on the functional organization of human LysRS and multi-tRNA synthetase complexes in vivo.
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Affiliation(s)
- Soon Bin Kwon
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Ji Eun Yu
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Chan Park
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Jiseop Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
| | - Baik L Seong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.
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33
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Bevilacqua PC, Assmann SM. Technique Development for Probing RNA Structure In Vivo and Genome-Wide. Cold Spring Harb Perspect Biol 2018; 10:a032250. [PMID: 30275275 PMCID: PMC6169808 DOI: 10.1101/cshperspect.a032250] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
How organisms perceive and respond to their surroundings is one of the great questions in biology. It is clear that RNA plays key roles in sensing. Cellular and environmental cues that RNA responds to include temperature, ions, metabolites, and biopolymers. Recent advances in next-generation sequencing and in vivo chemical probing have provided unprecedented insights into RNA folding in vivo and genome-wide. Patterns of chemical reactivity have implicated control of gene expression by RNA and aided prediction of RNA structure. Central to these advances has been development of molecular biological and chemical techniques. Key advances are improvements in the quality, cost, and throughput of library preparation; availability of a wider array of chemicals for probing RNA structure in vivo; and robustness and user friendliness of data analysis. Insights from probing transcriptomes and future directions are provided.
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Affiliation(s)
- Philip C Bevilacqua
- Departments of Chemistry and Biochemistry & Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Sarah M Assmann
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802
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Wallis CP, Richman TR, Filipovska A, Rackham O. Tighter Ligand Binding Can Compensate for Impaired Stability of an RNA-Binding Protein. ACS Chem Biol 2018; 13:1499-1505. [PMID: 29808990 DOI: 10.1021/acschembio.8b00424] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It has been widely shown that ligand-binding residues, by virtue of their orientation, charge, and solvent exposure, often have a net destabilizing effect on proteins that is offset by stability conferring residues elsewhere in the protein. This structure-function trade-off can constrain possible adaptive evolutionary changes of function and may hamper protein engineering efforts to design proteins with new functions. Here, we present evidence from a large randomized mutant library screen that, in the case of PUF RNA-binding proteins, this structural relationship may be inverted and that active-site mutations that increase protein activity are also able to compensate for impaired stability. We show that certain mutations in RNA-protein binding residues are not necessarily destabilizing and that increased ligand-binding can rescue an insoluble, unstable PUF protein. We hypothesize that these mutations restabilize the protein via thermodynamic coupling of protein folding and RNA binding.
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Affiliation(s)
- Christopher P. Wallis
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Tara R. Richman
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
- School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
- School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
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35
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Ramachandran R, Ciaccia PN, Filsuf TA, Jha JK, Chattoraj DK. Chromosome 1 licenses chromosome 2 replication in Vibrio cholerae by doubling the crtS gene dosage. PLoS Genet 2018; 14:e1007426. [PMID: 29795553 PMCID: PMC5991422 DOI: 10.1371/journal.pgen.1007426] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/06/2018] [Accepted: 05/17/2018] [Indexed: 12/20/2022] Open
Abstract
Initiation of chromosome replication in bacteria is precisely timed in the cell cycle. Bacteria that harbor multiple chromosomes face the additional challenge of orchestrating replication initiation of different chromosomes. In Vibrio cholerae, the smaller of its two chromosomes, Chr2, initiates replication after Chr1 such that both chromosomes terminate replication synchronously. The delay is due to the dependence of Chr2 initiation on the replication of a site, crtS, on Chr1. The mechanism by which replication of crtS allows Chr2 replication remains unclear. Here, we show that blocking Chr1 replication indeed blocks Chr2 replication, but providing an extra crtS copy in replication-blocked Chr1 permitted Chr2 replication. This demonstrates that unreplicated crtS copies have significant activity, and suggests that a role of replication is to double the copy number of the site that sufficiently increases its activity for licensing Chr2 replication. We further show that crtS activity promotes the Chr2-specific initiator function and that this activity is required in every cell cycle, as would be expected of a cell-cycle regulator. This study reveals how increase of gene dosage through replication can be utilized in a critical regulatory switch.
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Affiliation(s)
- Revathy Ramachandran
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Peter N. Ciaccia
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Tara A. Filsuf
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jyoti K. Jha
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Dhruba K. Chattoraj
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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36
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Alberti S, Carra S. Quality Control of Membraneless Organelles. J Mol Biol 2018; 430:4711-4729. [PMID: 29758260 DOI: 10.1016/j.jmb.2018.05.013] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/04/2018] [Accepted: 05/04/2018] [Indexed: 02/06/2023]
Abstract
The formation of membraneless organelles (MLOs) by phase separation has emerged as a new way of organizing the cytoplasm and nucleoplasm of cells. Examples of MLOs forming via phase separation are nucleoli in the nucleus and stress granules in the cytoplasm. The main components of these MLOs are macromolecules such as RNAs and proteins. In order to assemble by phase separation, these proteins and RNAs have to undergo many cooperative interactions. These cooperative interactions are supported by specific molecular features within phase-separating proteins, such as multivalency and the presence of disordered domains that promote weak and transient interactions. However, these features also predispose phase-separating proteins to aberrant behavior. Indeed, evidence is emerging for a strong link between phase-separating proteins, MLOs, and age-related diseases. In this review, we discuss recent progress in understanding the formation, properties, and functions of MLOs. We pay special attention to the emerging link between MLOs and age-related diseases, and we explain how changes in the composition and physical properties of MLOs promote their conversion into an aberrant state. Furthermore, we discuss the key role of the protein quality control machinery in regulating the properties and functions of MLOs and thus in preventing age-related diseases.
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Affiliation(s)
- Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany.
| | - Serena Carra
- Department of Biomedical, Metabolic and Neural Science, University of Modena and Reggio Emilia, Center for Neuroscience and Neurotechnology, 41125 Modena, Italy.
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37
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Yang SW, Jang YH, Kwon SB, Lee YJ, Chae W, Byun YH, Kim P, Park C, Lee YJ, Kim CK, Kim YS, Choi SI, Seong BL. Harnessing an RNA-mediated chaperone for the assembly of influenza hemagglutinin in an immunologically relevant conformation. FASEB J 2018; 32:2658-2675. [PMID: 29295864 PMCID: PMC5901386 DOI: 10.1096/fj.201700747rr] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/18/2017] [Indexed: 01/29/2023]
Abstract
A novel protein-folding function of RNA has been recognized, which can outperform previously known molecular chaperone proteins. The RNA as a molecular chaperone (chaperna) activity is intrinsic to some ribozymes and is operational during viral infections. Our purpose was to test whether influenza hemagglutinin (HA) can be assembled in a soluble, trimeric, and immunologically activating conformation by means of an RNA molecular chaperone (chaperna) activity. An RNA-interacting domain (RID) from the host being immunized was selected as a docking tag for RNA binding, which served as a transducer for the chaperna function for de novo folding and trimeric assembly of RID-HA1. Mutations that affect tRNA binding greatly increased the soluble aggregation defective in trimer assembly, suggesting that RNA interaction critically controls the kinetic network in the folding/assembly pathway. Immunization of mice resulted in strong hemagglutination inhibition and high titers of a neutralizing antibody, providing sterile protection against a lethal challenge and confirming the immunologically relevant HA conformation. The results may be translated into a rapid response to a new influenza pandemic. The harnessing of the novel chaperna described herein with immunologically tailored antigen-folding functions should serve as a robust prophylactic and diagnostic tool for viral infections.-Yang, S. W., Jang, Y. H., Kwon, S. B., Lee, Y. J., Chae, W., Byun, Y. H., Kim, P., Park, C., Lee, Y. J., Kim, C. K., Kim, Y. S., Choi, S. I., Seong, B. L. Harnessing an RNA-mediated chaperone for the assembly of influenza hemagglutinin in an immunologically relevant conformation.
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MESH Headings
- Animals
- Antibodies, Neutralizing/immunology
- Antibodies, Viral/immunology
- Female
- Hemagglutinin Glycoproteins, Influenza Virus/biosynthesis
- Hemagglutinin Glycoproteins, Influenza Virus/chemistry
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Immunization
- Influenza A virus/genetics
- Influenza A virus/immunology
- Influenza A virus/metabolism
- Mice
- Mice, Inbred BALB C
- Molecular Chaperones/chemistry
- Molecular Chaperones/genetics
- Molecular Chaperones/immunology
- Molecular Chaperones/metabolism
- Mutation
- Protein Folding
- Protein Multimerization
- RNA, Transfer/chemistry
- RNA, Transfer/genetics
- RNA, Transfer/immunology
- RNA, Transfer/metabolism
- Rabbits
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Affiliation(s)
- Seung Won Yang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Yo Han Jang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Soon Bin Kwon
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Yoon Jae Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Wonil Chae
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Young Ho Byun
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Paul Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Chan Park
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Young Jae Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Choon Kang Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Young Seok Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Seong Il Choi
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Baik Lin Seong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
- Vaccine Translational Research Center, Yonsei University, Seoul, South Korea
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38
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Recombinant adenylate kinase 3 from liver fluke Clonorchis sinensis for histochemical analysis and serodiagnosis of clonorchiasis. Parasitology 2018; 145:1531-1539. [PMID: 29580315 DOI: 10.1017/s0031182018000434] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Due to the lack of an effective prophylactic intervention and diagnosis, human liver fluke Clonorchis sinensis continues to afflict a large human population, causing a chronic inflammatory bile duct disease. With an aim to identify target antigens for sensitive serodiagnosis, adenylate kinase 3 of C. sinensis (CsAK3) was successfully expressed in soluble form in Escherichia coli by fusion to an RNA-interacting domain derived from human Lys-tRNA synthetase and purified by Ni2+-affinity chromatography. Anti-CsAK3 serum was raised by immunization of mice, and Western blotting confirmed that CsAK3 was expressed in adult-stage C. sinensis. Histochemical analysis showed that CsAK3 was localized to the subtegumental tissue of C. sinensis and was excreted into the bile duct of the host. When tested against sera from various parasite-infected patients by enzyme-linked immunosorbent assay, the recombinant CsAK3 elicited a specific response to C. sinensis-infected sera. The results suggest that CsAK3, either alone or in combination with other antigens, could be used for improving the clinical diagnosis of clonorchiasis.
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39
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Daher M, Widom JR, Tay W, Walter NG. Soft Interactions with Model Crowders and Non-canonical Interactions with Cellular Proteins Stabilize RNA Folding. J Mol Biol 2017; 430:509-523. [PMID: 29128594 DOI: 10.1016/j.jmb.2017.10.030] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/22/2017] [Accepted: 10/30/2017] [Indexed: 12/18/2022]
Abstract
Living cells contain diverse biopolymers, creating a heterogeneous crowding environment, the impact of which on RNA folding is poorly understood. Here, we have used single-molecule fluorescence resonance energy transfer to monitor tertiary structure formation of the hairpin ribozyme as a model to probe the effects of polyethylene glycol and yeast cell extract as crowding agents. As expected, polyethylene glycol stabilizes the docked, catalytically active state of the ribozyme, in part through excluded volume effects; unexpectedly, we found evidence that it additionally displays soft, non-specific interactions with the ribozyme. Yeast extract has a profound effect on folding at protein concentrations 1000-fold lower than found intracellularly, suggesting the dominance of specific interactions over volume exclusion. Gel shift assays and affinity pull-down followed by mass spectrometry identified numerous non-canonical RNA-binding proteins that stabilize ribozyme folding; the apparent chaperoning activity of these ubiquitous proteins significantly compensates for the low-counterion environment of the cell.
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Affiliation(s)
- May Daher
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Julia R Widom
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Wendy Tay
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Nils G Walter
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109-1055, USA.
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40
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Bou-Nader C, Pecqueur L, Cornu D, Lombard M, Dezi M, Nicaise M, Velours C, Fontecave M, Hamdane D. Power of protein/tRNA functional assembly against aberrant aggregation. Phys Chem Chem Phys 2017; 19:28014-28027. [PMID: 29034944 DOI: 10.1039/c7cp05599d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Understanding the mechanisms of protein oligomerization and aggregation is a major concern for biotechnology and medical purposes. However, significant challenges remain in determining the mechanism of formation of these superstructures and the environmental factors that can precisely modulate them. Notably the role that a functional ligand plays in the process of protein aggregation is largely unexplored. We herein address these issues with an original flavin-dependent RNA methyltransferase (TrmFO) used as a protein model since this protein employs a complex set of cofactors and ligands for catalysis. Here, we show that TrmFO carries an unstable protein structure that can partially mis-unfold leading to either formation of irregular and nonfunctional soluble oligomers endowed with hyper-thermal stability or large amorphous aggregates in the presence of salts. Mutagenesis confirmed that this peculiarity is an intrinsic property of a polypeptide and it is independent of the flavin coenzyme. Structural characterization and kinetic studies identified several regions of the protein that enjoy conformational changes and more particularly pinpointed the N-terminal subdomain as being a key element in the mechanisms of oligomerization and aggregation. Only stabilization of this region via tRNA suppresses these aberrant protein states. Although protein chaperones emerged as major actors against aggregation, our study emphasizes that other powerful mechanisms exist such as the stabilizing effect of functional assemblies that provide an additional layer of protection against the instability of the proteome.
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Affiliation(s)
- Charles Bou-Nader
- Laboratoire de Chimie des Processus Biologiques, CNRS-UMR 8229, Collège De France, Université Pierre et marie Curie, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France.
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41
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Abstract
The ribosome is imprinted with a detailed molecular chronology of the origins and early evolution of proteins. Here we show that when arranged by evolutionary phase of ribosomal evolution, ribosomal protein (rProtein) segments reveal an atomic level history of protein folding. The data support a model in which aboriginal oligomers evolved into globular proteins in a hierarchical step-wise process. Complexity of assembly and folding of polypeptide increased incrementally in concert with expansion of rRNA. (i) Short random coil proto-peptides bound to rRNA, and (ii) lengthened over time and coalesced into β–β secondary elements. These secondary elements (iii) accreted and collapsed, primarily into β-domains. Domains (iv) accumulated and gained complex super-secondary structures composed of mixtures of α-helices and β-strands. Early protein evolution was guided and accelerated by interactions with rRNA. rRNA and proto-peptide provided mutual protection from chemical degradation and disassembly. rRNA stabilized polypeptide assemblies, which evolved in a stepwise process into globular domains, bypassing the immense space of random unproductive sequences. Coded proteins originated as oligomers and polymers created by the ribosome, on the ribosome and for the ribosome. Synthesis of increasingly longer products was iteratively coupled with lengthening and maturation of the ribosomal exit tunnel. Protein catalysis appears to be a late byproduct of selection for sophisticated and finely controlled assembly.
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Affiliation(s)
- Nicholas A Kovacs
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA
| | - Anton S Petrov
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA
| | - Kathryn A Lanier
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA
| | - Loren Dean Williams
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA
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42
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Voisset C, Blondel M, Jones GW, Friocourt G, Stahl G, Chédin S, Béringue V, Gillet R. The double life of the ribosome: When its protein folding activity supports prion propagation. Prion 2017; 11:89-97. [PMID: 28362551 DOI: 10.1080/19336896.2017.1303587] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
It is no longer necessary to demonstrate that ribosome is the central machinery of protein synthesis. But it is less known that it is also key player of the protein folding process through another conserved function: the protein folding activity of the ribosome (PFAR). This ribozyme activity, discovered more than 2 decades ago, depends upon the domain V of the large rRNA within the large subunit of the ribosome. Surprisingly, we discovered that anti-prion compounds are also potent PFAR inhibitors, highlighting an unexpected link between PFAR and prion propagation. In this review, we discuss the ancestral origin of PFAR in the light of the ancient RNA world hypothesis. We also consider how this ribosomal activity fits into the landscape of cellular protein chaperones involved in the appearance and propagation of prions and other amyloids in mammals. Finally, we examine how drugs targeting the protein folding activity of the ribosome could be active against mammalian prion and other protein aggregation-based diseases, making PFAR a promising therapeutic target for various human protein misfolding diseases.
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Affiliation(s)
- Cécile Voisset
- a Inserm UMR 1078 , Université de Bretagne Occidentale, Faculté de Médecine et des Sciences de la Santé, Etablissement Français du Sang (EFS) Bretagne, CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire , Brest , France
| | - Marc Blondel
- a Inserm UMR 1078 , Université de Bretagne Occidentale, Faculté de Médecine et des Sciences de la Santé, Etablissement Français du Sang (EFS) Bretagne, CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire , Brest , France
| | - Gary W Jones
- b School of Clinical and Applied Sciences , Faculty of Health and Social Sciences, Leeds Beckett University , Leeds , UK
| | - Gaëlle Friocourt
- a Inserm UMR 1078 , Université de Bretagne Occidentale, Faculté de Médecine et des Sciences de la Santé, Etablissement Français du Sang (EFS) Bretagne, CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire , Brest , France
| | - Guillaume Stahl
- c Laboratoire de Biologie Moléculaire Eucaryotes , CNRS, Université de Toulouse , Toulouse , France
| | - Stéphane Chédin
- d Institute for Integrative Biology of the Cell (I2BC), UMR 9198, CEA, CNRS, Université Paris-Sud, CEA/Saclay, SBIGeM , Gif-sur-Yvette , France
| | | | - Reynald Gillet
- f Université de Rennes 1, CNRS UMR 6290 IGDR , Rennes , France
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Kim JM, Choi HS, Seong BL. The folding competence of HIV-1 Tat mediated by interaction with TAR RNA. RNA Biol 2017; 14:926-937. [PMID: 28418268 DOI: 10.1080/15476286.2017.1311455] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The trans-activator Tat protein of HIV-1 belongs to the large family of intrinsically disordered proteins (IDPs), and is known to recruit various host proteins for the transactivation of viral RNA synthesis. Tat protein interacts with the transactivator response RNA (TAR RNA), exhibiting RNA chaperone activities for structural rearrangement of interacting RNAs. Here, considering that Tat-TAR RNA interaction is mutually cooperative, we examined the potential role of TAR RNA as Chaperna - RNA that provides chaperone function to proteins - for the folding of HIV-1 Tat. Using EGFP fusion as an indirect indicator for folding status, we monitored Tat-EGFP folding in HeLa cells via time-lapse fluorescence microscopy. The live cell imaging showed that the rate and the extent of folding of Tat-EGFP were stimulated by TAR RNA. The purified Tat-EGFP was denatured and the fluorescence was monitored in vitro under renaturation condition. The fluorescence was significantly increased by TAR RNA, and the mutations in TAR RNA that affected the interaction with Tat protein failed to promote Tat refolding. The results suggest that TAR RNA stabilizes Tat as unfolded, but prevents it from misfolding, and maintaining its folding competence for interaction with multiple host factors toward its transactivation. The Chaperna function of virally encoded RNA in establishing proteome link at the viral-host interface provides new insights to as yet largely unexplored RNA mediated protein folding in normal and dysregulated cellular metabolism.
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Affiliation(s)
- Jung Min Kim
- a Department of Biotechnology , College of Life Science and Biotechnology, Yonsei University , Seoul , South Korea.,b Vaccine Translational Research Center , Yonsei University , Seoul , South Korea
| | - Hee Sun Choi
- c Department of Pathology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Baik Lin Seong
- a Department of Biotechnology , College of Life Science and Biotechnology, Yonsei University , Seoul , South Korea.,b Vaccine Translational Research Center , Yonsei University , Seoul , South Korea
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Abstract
Recently, we found that RNA is a remarkably powerful chaperone that can bind to unfolded proteins and transfer them to Hsp70 for refolding. Combined with past studies on RNA-chaperone interactions, we propose a model for how chaperone RNA activity may contribute to the cellular response to stress.
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Affiliation(s)
- Scott Horowitz
- a University of Michigan, Department of Molecular, Cellular, and Developmental Biology , Ann Arbor , MI , USA.,b Howard Hughes Medical Institute , Chevy Chase , MD , USA
| | - James C A Bardwell
- a University of Michigan, Department of Molecular, Cellular, and Developmental Biology , Ann Arbor , MI , USA.,b Howard Hughes Medical Institute , Chevy Chase , MD , USA
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Koldewey P, Stull F, Horowitz S, Martin R, Bardwell JCA. Forces Driving Chaperone Action. Cell 2016; 166:369-379. [PMID: 27293188 DOI: 10.1016/j.cell.2016.05.054] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/02/2016] [Accepted: 05/16/2016] [Indexed: 11/30/2022]
Abstract
It is still unclear what molecular forces drive chaperone-mediated protein folding. Here, we obtain a detailed mechanistic understanding of the forces that dictate the four key steps of chaperone-client interaction: initial binding, complex stabilization, folding, and release. Contrary to the common belief that chaperones recognize unfolding intermediates by their hydrophobic nature, we discover that the model chaperone Spy uses long-range electrostatic interactions to rapidly bind to its unfolded client protein Im7. Short-range hydrophobic interactions follow, which serve to stabilize the complex. Hydrophobic collapse of the client protein then drives its folding. By burying hydrophobic residues in its core, the client's affinity to Spy decreases, which causes client release. By allowing the client to fold itself, Spy circumvents the need for client-specific folding instructions. This mechanism might help explain how chaperones can facilitate the folding of various unrelated proteins.
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Affiliation(s)
- Philipp Koldewey
- Department of Molecular, Cellular and Developmental Biology, and the Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Frederick Stull
- Department of Molecular, Cellular and Developmental Biology, and the Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Scott Horowitz
- Department of Molecular, Cellular and Developmental Biology, and the Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Raoul Martin
- Department of Molecular, Cellular and Developmental Biology, and the Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - James C A Bardwell
- Department of Molecular, Cellular and Developmental Biology, and the Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA.
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