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Bohl V, Mogk A. When the going gets tough, the tough get going-Novel bacterial AAA+ disaggregases provide extreme heat resistance. Environ Microbiol 2024; 26:e16677. [PMID: 39039821 DOI: 10.1111/1462-2920.16677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/05/2024] [Indexed: 07/24/2024]
Abstract
Heat stress can lead to protein misfolding and aggregation, potentially causing cell death due to the loss of essential proteins. Bacteria, being particularly exposed to environmental stress, are equipped with disaggregases that rescue these aggregated proteins. The bacterial Hsp70 chaperone DnaK and the ATPase associated with diverse cellular activities protein ClpB form the canonical disaggregase in bacteria. While this combination operates effectively during physiological heat stress, it is ineffective against massive aggregation caused by temperature-based sterilization protocols used in the food industry and clinics. This leaves bacteria unprotected against these thermal processes. However, bacteria that can withstand extreme, man-made stress conditions have emerged. These bacteria possess novel ATPase associated with diverse cellular activities disaggregases, ClpG and ClpL, which are key players in extreme heat resistance. These disaggregases, present in selected Gram-negative or Gram-positive bacteria, respectively, function superiorly by exhibiting increased thermal stability and enhanced threading power compared to DnaK/ClpB. This enables ClpG and ClpL to operate at extreme temperatures and process large and tight protein aggregates, thereby contributing to heat resistance. The genes for ClpG and ClpL are often encoded on mobile genomic islands or conjugative plasmids, allowing for their rapid spread among bacteria via horizontal gene transfer. This threatens the efficiency of sterilization protocols. In this review, we describe the various bacterial disaggregases identified to date, characterizing their commonalities and the specific features that enable these novel disaggregases to provide stress protection against extreme stress conditions.
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Affiliation(s)
- Valentin Bohl
- Faculty of Biosciences, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
| | - Axel Mogk
- Faculty of Biosciences, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
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Mack KL, Kim H, Barbieri EM, Lin J, Braganza S, Jackrel ME, DeNizio JE, Yan X, Chuang E, Tariq A, Cupo RR, Castellano LM, Caldwell KA, Caldwell GA, Shorter J. Tuning Hsp104 specificity to selectively detoxify α-synuclein. Mol Cell 2023; 83:3314-3332.e9. [PMID: 37625404 PMCID: PMC10530207 DOI: 10.1016/j.molcel.2023.07.029] [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: 07/04/2023] [Revised: 07/19/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023]
Abstract
Hsp104 is an AAA+ protein disaggregase that solubilizes and reactivates proteins trapped in aggregated states. We have engineered potentiated Hsp104 variants to mitigate toxic misfolding of α-synuclein, TDP-43, and FUS implicated in fatal neurodegenerative disorders. Though potent disaggregases, these enhanced Hsp104 variants lack substrate specificity and can have unfavorable off-target effects. Here, to lessen off-target effects, we engineer substrate-specific Hsp104 variants. By altering Hsp104 pore loops that engage substrate, we disambiguate Hsp104 variants that selectively suppress α-synuclein toxicity but not TDP-43 or FUS toxicity. Remarkably, α-synuclein-specific Hsp104 variants emerge that mitigate α-synuclein toxicity via distinct ATPase-dependent mechanisms involving α-synuclein disaggregation or detoxification of soluble α-synuclein conformers. Importantly, both types of α-synuclein-specific Hsp104 variant reduce dopaminergic neurodegeneration in a C. elegans model of Parkinson's disease more effectively than non-specific variants. We suggest that increasing the substrate specificity of enhanced disaggregases could be applied broadly to tailor therapeutics for neurodegenerative disease.
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Affiliation(s)
- Korrie L Mack
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hanna Kim
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Edward M Barbieri
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - JiaBei Lin
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sylvanne Braganza
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Meredith E Jackrel
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jamie E DeNizio
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaohui Yan
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Edward Chuang
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Amber Tariq
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ryan R Cupo
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Laura M Castellano
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kim A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Guy A Caldwell
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL 35487, USA.
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Pharmacology Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
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Kim M, Swenson J, McLoughlin F, Vierling E. Mutation of the polyadenylation complex subunit CstF77 reveals that mRNA 3' end formation and HSP101 levels are critical for a robust heat stress response. THE PLANT CELL 2023; 35:924-941. [PMID: 36472129 PMCID: PMC9940869 DOI: 10.1093/plcell/koac351] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
Heat shock protein 101 (HSP101) in plants, and bacterial and yeast orthologs, is essential for thermotolerance. To investigate thermotolerance mechanisms involving HSP101, we performed a suppressor screen in Arabidopsis thaliana of a missense HSP101 allele (hot1-4). hot1-4 plants are sensitive to acclimation heat treatments that are otherwise permissive for HSP101 null mutants, indicating that the hot1-4 protein is toxic. We report one suppressor (shot2, suppressor of hot1-4 2) has a missense mutation of a conserved residue in CLEAVAGE STIMULATION FACTOR77 (CstF77), a subunit of the polyadenylation complex critical for mRNA 3' end maturation. We performed ribosomal RNA depletion RNA-Seq and captured transcriptional readthrough with a custom bioinformatics pipeline. Acclimation heat treatment caused transcriptional readthrough in hot1-4 shot2, with more readthrough in heat-induced genes, reducing the levels of toxic hot1-4 protein and suppressing hot1-4 heat sensitivity. Although shot2 mutants develop like the wild type in the absence of stress and survive mild heat stress, reduction of heat-induced genes and decreased HSP accumulation makes shot2 in HSP101 null and wild-type backgrounds sensitive to severe heat stress. Our study reveals the critical function of CstF77 for 3' end formation of mRNA and the dominant role of HSP101 in dictating the outcome of severe heat stress.
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Affiliation(s)
- Minsoo Kim
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - John Swenson
- Program for Organismic and Evolutionary Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Fionn McLoughlin
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Elizabeth Vierling
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts 01003, USA
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Low KJY, Venkatraman A, Mehta JS, Pervushin K. Molecular mechanisms of amyloid disaggregation. J Adv Res 2022; 36:113-132. [PMID: 35127169 PMCID: PMC8799873 DOI: 10.1016/j.jare.2021.05.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 04/13/2021] [Accepted: 05/16/2021] [Indexed: 12/17/2022] Open
Abstract
Importance of disaggregation mechanism and innate disaggregation in living systems. Different types and mechanism of disaggregation reported in literature. Structural details of the interactions and the disaggregation mechanisms. Amyloid disaggregation in protein aggregation disorders as a potential treatment. Proposed amyloid disaggregation mechanism of an ATP-independent chaperone (L-PGDS).
Introduction Protein aggregation and deposition of uniformly arranged amyloid fibrils in the form of plaques or amorphous aggregates is characteristic of amyloid diseases. The accumulation and deposition of proteins result in toxicity and cause deleterious effects on affected individuals known as amyloidosis. There are about fifty different proteins and peptides involved in amyloidosis including neurodegenerative diseases and diseases affecting vital organs. Despite the strenuous effort to find a suitable treatment option for these amyloid disorders, very few compounds had made it to unsuccessful clinical trials. It has become a compelling challenge to understand and manage amyloidosis with the increased life expectancy and ageing population. Objective While most of the currently available literature and knowledge base focus on the amyloid inhibitory mechanism as a treatment option, it is equally important to organize and understand amyloid disaggregation strategies. Disaggregation strategies are important and crucial as they are present innately functional in many living systems and dissolution of preformed amyloids may provide a direct benefit in many pathological conditions. In this review, we have compiled the known amyloid disaggregation mechanism, interactions, and possibilities of using disaggregases as a treatment option for amyloidosis. Methods We have provided the structural details using protein-ligand docking models to visualize the interaction between these disaggregases with amyloid fibrils and their respective proposed amyloid disaggregation mechanisms. Results After reviewing and comparing the different amyloid disaggregase systems and their proposed mechanisms, we presented two different hypotheses for ATP independent disaggregases using L-PGDS as a model. Conclusion Finally, we have highlighted the importance of understanding the underlying disaggregation mechanisms used by these chaperones and organic compounds before the implementation of these disaggregases as a potential treatment option for amyloidosis.
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Avendaño-Herrera R, Saldivia P, Bethke J, Vargas C, Hernández M. Proteomic analysis reveals Renibacterium salmoninarum grown under iron-limited conditions induces iron uptake mechanisms and overproduction of the 57-kDa protein. JOURNAL OF FISH DISEASES 2022; 45:289-300. [PMID: 34791674 DOI: 10.1111/jfd.13554] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/28/2021] [Accepted: 10/31/2021] [Indexed: 06/13/2023]
Abstract
Renibacterium salmoninarum, a slow-growing facultative intracellular pathogen, is the causative agent of bacterial kidney disease, a chronic, progressive and granulomatous infection that threatens farmed and wild salmonids worldwide. Pathogenic R. salmoninarum colonizes tissues and invades the host through cell surface-associated and secreted proteins. While correlations between iron acquisition genes and virulence have been demonstrated in vitro, these mechanisms have not undergone proteomic characterization. The present study applied a proteomic approach to elucidate the differences between the virulent Chilean R. salmoninarum H-2 strain and the type strain ATCC 33209T . Analyses were conducted under normal (control) and iron-limited conditions (DIP) emulating the host environment. Interestingly, strain H-2 apparently responded better to the iron-limited condition-for example, only this strain presented a significantly enriched iron ion homeostasis pathway. Furthermore, key virulence factors related to an iron-limited environment were more abundant in strain H-2. Importantly, the lack of iron favoured the expression of the 57-kDa protein in strain H-2, the principal virulence factor for R. salmoninarum. Our findings can be employed in the design and development of treatments targeted to iron uptake mechanisms (e.g. siderophore synthesis or haem uptake), which represents a promising therapeutic approach for treating this persistent fastidious bacterium.
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Affiliation(s)
- Ruben Avendaño-Herrera
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Viña del Mar, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Universidad Andrés Bello, Quintay, Chile
| | - Pablo Saldivia
- Division of Biotechnology, MELISA Institute, San Pedro de la Paz, Concepción, Chile
| | - Jorn Bethke
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Viña del Mar, Chile
| | - Cristian Vargas
- Division of Biotechnology, MELISA Institute, San Pedro de la Paz, Concepción, Chile
| | - Mauricio Hernández
- Division of Biotechnology, MELISA Institute, San Pedro de la Paz, Concepción, Chile
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Schilke BA, Craig EA. Essentiality of Sis1, a J-domain protein Hsp70 cochaperone, can be overcome by Tti1, a specialized PIKK chaperone. Mol Biol Cell 2021; 33:br3. [PMID: 34935410 PMCID: PMC9250385 DOI: 10.1091/mbc.e21-10-0493] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
J-domain protein cochaperones drive much of the functional diversity of Hsp70-based chaperone systems. Sis1 is the only essential J-domain protein of the cytosol/nucleus of Saccharomyces cerevisiae. Why it is required for cell growth is not understood, nor how critical its role is in regulation of heat shock transcription factor 1 (Hsf1). We report that single-residue substitutions in Tti1, a component of the heterotrimeric TTT complex, a specialized chaperone system for phosphatidylinositol 3-kinase-related kinase (PIKK) proteins, allow growth of cells lacking Sis1. Upon depletion of Sis1, cells become hypersensitive to rapamycin, a specific inhibitor of TORC1 kinase. In addition, levels of the three essential PIKKs (Mec1, Tra1, and Tor2), as well as Tor1, decrease upon Sis1 depletion. Overexpression of Tti1 allows growth without an increase in the other subunits of the TTT complex, Tel2 and Tti2, suggesting that it can function independent of the complex. Cells lacking Sis1, with viability supported by Tti1 suppressor, substantially up-regulate some, but not all, heat shock elements activated by Hsf1. Together, our results suggest that Sis1 is required as a cochaperone of Hsp70 for the folding/maintenance of PIKKs, making Sis1 an essential gene, and its requirement for Hsf1 regulation is more nuanced than generally appreciated.
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Affiliation(s)
- Brenda A Schilke
- Department of Biochemistry, 433 Babcock Drive, University of Wisconsin - Madison, Madison, Wisconsin 53706
| | - Elizabeth A Craig
- Department of Biochemistry, 433 Babcock Drive, University of Wisconsin - Madison, Madison, Wisconsin 53706
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7
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Zhang X, Zhang X, Huang W, Ge X. The role of heat shock proteins in the regulation of fibrotic diseases. Biomed Pharmacother 2020; 135:111067. [PMID: 33383375 DOI: 10.1016/j.biopha.2020.111067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/08/2020] [Accepted: 11/20/2020] [Indexed: 12/29/2022] Open
Abstract
Heat shock proteins (HSPs) are key players to restore cell homeostasis and act as chaperones by assisting the folding and assembly of newly synthesized proteins and preventing protein aggregation. Recently, evidence has been accumulating that HSPs have been proven to have other functions except for the classical molecular chaperoning in that they play an important role in a wider range of fibrotic diseases via modulating cytokine induction and inflammation response, including lung fibrosis, liver fibrosis, and idiopathic pulmonary fibrosis. The recruitment of inflammatory cells, a large number of secretion of pro-fibrotic cytokines such as transforming growth factor-β1 (TGF-β1) and increased apoptosis, oxidative stress, and proteasomal system degradation are all events occurring during fibrogenesis, which might be associated with HSPs. However, their role on fibrotic process is not yet fully understood. In this review, we discuss new discoveries regarding the involvement of HSPs in the regulation of organ and tissue fibrosis, and note recent findings suggesting that HSPs may be a promising therapeutic target for improving the current frustrating outcome of fibrotic disorders.
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Affiliation(s)
- Xiaoling Zhang
- Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China; School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong, 226019, PR China.
| | - Xiaoyan Zhang
- Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China
| | - Wenmin Huang
- Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China
| | - Xiaoqun Ge
- Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225001, PR China; Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases, Yangzhou University, Yangzhou, 225001, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, 225009, PR China.
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8
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March ZM, Sweeney K, Kim H, Yan X, Castellano LM, Jackrel ME, Lin J, Chuang E, Gomes E, Willicott CW, Michalska K, Jedrzejczak RP, Joachimiak A, Caldwell KA, Caldwell GA, Shalem O, Shorter J. Therapeutic genetic variation revealed in diverse Hsp104 homologs. eLife 2020; 9:e57457. [PMID: 33319748 PMCID: PMC7785292 DOI: 10.7554/elife.57457] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 12/14/2020] [Indexed: 12/11/2022] Open
Abstract
The AAA+ protein disaggregase, Hsp104, increases fitness under stress by reversing stress-induced protein aggregation. Natural Hsp104 variants might exist with enhanced, selective activity against neurodegenerative disease substrates. However, natural Hsp104 variation remains largely unexplored. Here, we screened a cross-kingdom collection of Hsp104 homologs in yeast proteotoxicity models. Prokaryotic ClpG reduced TDP-43, FUS, and α-synuclein toxicity, whereas prokaryotic ClpB and hyperactive variants were ineffective. We uncovered therapeutic genetic variation among eukaryotic Hsp104 homologs that specifically antagonized TDP-43 condensation and toxicity in yeast and TDP-43 aggregation in human cells. We also uncovered distinct eukaryotic Hsp104 homologs that selectively antagonized α-synuclein condensation and toxicity in yeast and dopaminergic neurodegeneration in C. elegans. Surprisingly, this therapeutic variation did not manifest as enhanced disaggregase activity, but rather as increased passive inhibition of aggregation of specific substrates. By exploring natural tuning of this passive Hsp104 activity, we elucidated enhanced, substrate-specific agents that counter proteotoxicity underlying neurodegeneration.
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Affiliation(s)
- Zachary M March
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Department of Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - Katelyn Sweeney
- Department of Genetics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Center for Cellular and Molecular Therapeutics, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
| | - Hanna Kim
- Department of Biological Sciences, The University of AlabamaTuscaloosaUnited States
| | - Xiaohui Yan
- Department of Biological Sciences, The University of AlabamaTuscaloosaUnited States
| | - Laura M Castellano
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Pharmacology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - Meredith E Jackrel
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - JiaBei Lin
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - Edward Chuang
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Pharmacology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - Edward Gomes
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
| | - Corey W Willicott
- Department of Biological Sciences, The University of AlabamaTuscaloosaUnited States
| | - Karolina Michalska
- Structural Biology Center, X-ray Science Division, Argonne National LaboratoryArgonneUnited States
- Department of Biochemistry and Molecular Biology, University of ChicagoChicagoUnited States
| | - Robert P Jedrzejczak
- Structural Biology Center, X-ray Science Division, Argonne National LaboratoryArgonneUnited States
| | - Andrzej Joachimiak
- Structural Biology Center, X-ray Science Division, Argonne National LaboratoryArgonneUnited States
- Department of Biochemistry and Molecular Biology, University of ChicagoChicagoUnited States
| | - Kim A Caldwell
- Department of Biological Sciences, The University of AlabamaTuscaloosaUnited States
| | - Guy A Caldwell
- Department of Biological Sciences, The University of AlabamaTuscaloosaUnited States
| | - Ophir Shalem
- Department of Genetics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Center for Cellular and Molecular Therapeutics, Children’s Hospital of PhiladelphiaPhiladelphiaUnited States
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Department of Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Cell and Molecular Biology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
- Pharmacology Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaUnited States
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Structural and kinetic basis for the regulation and potentiation of Hsp104 function. Proc Natl Acad Sci U S A 2020; 117:9384-9392. [PMID: 32277033 DOI: 10.1073/pnas.1921968117] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Hsp104 provides a valuable model for the many essential proteostatic functions performed by the AAA+ superfamily of protein molecular machines. We developed and used a powerful hydrogen exchange mass spectrometry (HX MS) analysis that can provide positionally resolved information on structure, dynamics, and energetics of the Hsp104 molecular machinery, even during functional cycling. HX MS reveals that the ATPase cycle is rate-limited by ADP release from nucleotide-binding domain 1 (NBD1). The middle domain (MD) serves to regulate Hsp104 activity by slowing ADP release. Mutational potentiation accelerates ADP release, thereby increasing ATPase activity. It reduces time in the open state, thereby decreasing substrate protein loss. During active cycling, Hsp104 transits repeatedly between whole hexamer closed and open states. Under diverse conditions, the shift of open/closed balance can lead to premature substrate loss, normal processing, or the generation of a strong pulling force. HX MS exposes the mechanisms of these functions at near-residue resolution.
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10
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Sweeny EA, Tariq A, Gurpinar E, Go MS, Sochor MA, Kan ZY, Mayne L, Englander SW, Shorter J. Structural and mechanistic insights into Hsp104 function revealed by synchrotron X-ray footprinting. J Biol Chem 2020; 295:1517-1538. [PMID: 31882541 PMCID: PMC7008382 DOI: 10.1074/jbc.ra119.011577] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/23/2019] [Indexed: 01/11/2023] Open
Abstract
Hsp104 is a hexameric AAA+ ring translocase, which drives protein disaggregation in nonmetazoan eukaryotes. Cryo-EM structures of Hsp104 have suggested potential mechanisms of substrate translocation, but precisely how Hsp104 hexamers disaggregate proteins remains incompletely understood. Here, we employed synchrotron X-ray footprinting to probe the solution-state structures of Hsp104 monomers in the absence of nucleotide and Hsp104 hexamers in the presence of ADP or ATPγS (adenosine 5'-O-(thiotriphosphate)). Comparing side-chain solvent accessibilities between these three states illuminated aspects of Hsp104 structure and guided design of Hsp104 variants to probe the disaggregase mechanism in vitro and in vivo We established that Hsp104 hexamers switch from a more-solvated state in ADP to a less-solvated state in ATPγS, consistent with switching from an open spiral to a closed ring visualized by cryo-EM. We pinpointed critical N-terminal domain (NTD), NTD-nucleotide-binding domain 1 (NBD1) linker, NBD1, and middle domain (MD) residues that enable intrinsic disaggregase activity and Hsp70 collaboration. We uncovered NTD residues in the loop between helices A1 and A2 that can be substituted to enhance disaggregase activity. We elucidated a novel potentiated Hsp104 MD variant, Hsp104-RYD, which suppresses α-synuclein, fused in sarcoma (FUS), and TDP-43 toxicity. We disambiguated a secondary pore-loop in NBD1, which collaborates with the NTD and NBD1 tyrosine-bearing pore-loop to drive protein disaggregation. Finally, we defined Leu-601 in NBD2 as crucial for Hsp104 hexamerization. Collectively, our findings unveil new facets of Hsp104 structure and mechanism. They also connect regions undergoing large changes in solvation to functionality, which could have profound implications for protein engineering.
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Affiliation(s)
- Elizabeth A Sweeny
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
| | - Amber Tariq
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Esin Gurpinar
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Michelle S Go
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Matthew A Sochor
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Zhong-Yuan Kan
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Johnson Research Foundation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Leland Mayne
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Johnson Research Foundation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - S Walter Englander
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Johnson Research Foundation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - James Shorter
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania 19104; Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
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11
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The molecular principles governing the activity and functional diversity of AAA+ proteins. Nat Rev Mol Cell Biol 2019; 21:43-58. [PMID: 31754261 DOI: 10.1038/s41580-019-0183-6] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2019] [Indexed: 12/26/2022]
Abstract
ATPases associated with diverse cellular activities (AAA+ proteins) are macromolecular machines that convert the chemical energy contained in ATP molecules into powerful mechanical forces to remodel a vast array of cellular substrates, including protein aggregates, macromolecular complexes and polymers. AAA+ proteins have key functionalities encompassing unfolding and disassembly of such substrates in different subcellular localizations and, hence, power a plethora of fundamental cellular processes, including protein quality control, cytoskeleton remodelling and membrane dynamics. Over the past 35 years, many of the key elements required for AAA+ activity have been identified through genetic, biochemical and structural analyses. However, how ATP powers substrate remodelling and whether a shared mechanism underlies the functional diversity of the AAA+ superfamily were uncertain. Advances in cryo-electron microscopy have enabled high-resolution structure determination of AAA+ proteins trapped in the act of processing substrates, revealing a conserved core mechanism of action. It has also become apparent that this common mechanistic principle is structurally adjusted to carry out a diverse array of biological functions. Here, we review how substrate-bound structures of AAA+ proteins have expanded our understanding of ATP-driven protein remodelling.
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12
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Tariq A, Lin J, Noll MM, Torrente MP, Mack KL, Murillo OH, Jackrel ME, Shorter J. Potentiating Hsp104 activity via phosphomimetic mutations in the middle domain. FEMS Yeast Res 2019; 18:4969683. [PMID: 29788207 DOI: 10.1093/femsyr/foy042] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/10/2018] [Indexed: 12/13/2022] Open
Abstract
Hsp104 is a hexameric AAA + ATPase and protein disaggregase found in yeast, which can be potentiated via mutations in its middle domain (MD) to counter toxic phase separation by TDP-43, FUS and α-synuclein connected to devastating neurodegenerative disorders. Subtle missense mutations in the Hsp104 MD can enhance activity, indicating that post-translational modification of specific MD residues might also potentiate Hsp104. Indeed, several serine and threonine residues throughout Hsp104 can be phosphorylated in vivo. Here, we introduce phosphomimetic aspartate or glutamate residues at these positions and assess Hsp104 activity. Remarkably, phosphomimetic T499D/E and S535D/E mutations in the MD enable Hsp104 to counter TDP-43, FUS and α-synuclein aggregation and toxicity in yeast, whereas T499A/V/I and S535A do not. Moreover, Hsp104T499E and Hsp104S535E exhibit enhanced ATPase activity and Hsp70-independent disaggregase activity in vitro. We suggest that phosphorylation of T499 or S535 may elicit enhanced Hsp104 disaggregase activity in a reversible and regulated manner.
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Affiliation(s)
| | - JiaBei Lin
- Department of Biochemistry and Biophysics
| | | | | | - Korrie L Mack
- Department of Biochemistry and Biophysics
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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13
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Batista FA, Dores-Silva PR, Borges JC. Molecular Chaperones Involved in Protein Recovery from Aggregates are Present in Protozoa Causative of Malaria and Leishmaniasis. CURR PROTEOMICS 2018. [DOI: 10.2174/1570164615666180626123823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Molecular chaperones have several critical functions in protein metabolism. Among them,
some are involved in processes that culminate in the extraction of entangled polypeptides from protein
aggregates, releasing unfolded structures prone to be refolded or directed to degradation. This action
avoids the effect of toxic aggregates on cells and tissues. Molecular chaperones belonging to the
Hsp100 family are widely distributed from unicellular and sessile organisms up to fungi and plants,
exerting key functions related to the reduction of the effects caused by different forms of stress. The
Hsp100 proteins belong to the AAA+ (ATPases Associated with diverse cellular Activities) family and
form multichaperone systems with Hsp70 and small Hsp chaperones families. However, Hsp100 are
absent in metazoan, where protein disaggregation action is performed by a system involving the Hsp70
family, including Hsp110 and J-protein co-chaperones. Here, the structural and functional aspects of
these protein disaggregation systems will be reviewed and discussed in the perspective of the Hsp100
system absent in the metazoan kingdom. This feature focuses on Hsp100 as a hot spot for drug discovery
against human infectious diseases such as leishmaniasis and malaria, as Hsp100 is critical for microorganisms.
The current data available for Hsp100 in Leishmania spp. and Plasmodium spp. are also
reviewed.
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Affiliation(s)
- Fernanda A.H. Batista
- Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos, SP, Brazil
| | - Paulo R. Dores-Silva
- Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos, SP, Brazil
| | - Júlio C. Borges
- Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos, SP, Brazil
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14
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Chandramowlishwaran P, Sun M, Casey KL, Romanyuk AV, Grizel AV, Sopova JV, Rubel AA, Nussbaum-Krammer C, Vorberg IM, Chernoff YO. Mammalian amyloidogenic proteins promote prion nucleation in yeast. J Biol Chem 2018; 293:3436-3450. [PMID: 29330303 DOI: 10.1074/jbc.m117.809004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/26/2017] [Indexed: 12/26/2022] Open
Abstract
Fibrous cross-β aggregates (amyloids) and their transmissible forms (prions) cause diseases in mammals (including humans) and control heritable traits in yeast. Initial nucleation of a yeast prion by transiently overproduced prion-forming protein or its (typically, QN-rich) prion domain is efficient only in the presence of another aggregated (in most cases, QN-rich) protein. Here, we demonstrate that a fusion of the prion domain of yeast protein Sup35 to some non-QN-rich mammalian proteins, associated with amyloid diseases, promotes nucleation of Sup35 prions in the absence of pre-existing aggregates. In contrast, both a fusion of the Sup35 prion domain to a multimeric non-amyloidogenic protein and the expression of a mammalian amyloidogenic protein that is not fused to the Sup35 prion domain failed to promote prion nucleation, further indicating that physical linkage of a mammalian amyloidogenic protein to the prion domain of a yeast protein is required for the nucleation of a yeast prion. Biochemical and cytological approaches confirmed the nucleation of protein aggregates in the yeast cell. Sequence alterations antagonizing or enhancing amyloidogenicity of human amyloid-β (associated with Alzheimer's disease) and mouse prion protein (associated with prion diseases), respectively, antagonized or enhanced nucleation of a yeast prion by these proteins. The yeast-based prion nucleation assay, developed in our work, can be employed for mutational dissection of amyloidogenic proteins. We anticipate that it will aid in the identification of chemicals that influence initial amyloid nucleation and in searching for new amyloidogenic proteins in a variety of proteomes.
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Affiliation(s)
| | - Meng Sun
- From the School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Kristin L Casey
- From the School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Andrey V Romanyuk
- From the School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Anastasiya V Grizel
- the Laboratory of Amyloid Biology.,Institute of Translational Biomedicine, and
| | - Julia V Sopova
- the Laboratory of Amyloid Biology.,Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia.,the St. Petersburg Branch, N. I. Vavilov Institute of General Genetics, Russian Academy of Sciences, 199034 St. Petersburg, Russia
| | - Aleksandr A Rubel
- the Laboratory of Amyloid Biology.,Institute of Translational Biomedicine, and.,Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Carmen Nussbaum-Krammer
- the Zentrum für Molekulare Biologie der Universität Heidelberg, 69120 Heidelberg, Germany, and
| | - Ina M Vorberg
- the Deutsches Zentrum für Neurodegenerative Erkrankungen, 53175 Bonn, Germany
| | - Yury O Chernoff
- From the School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, .,the Laboratory of Amyloid Biology.,Institute of Translational Biomedicine, and
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15
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Abrahão J, Mokry DZ, Ramos CHI. Hsp78 (78 kDa Heat Shock Protein), a Representative AAA Family Member Found in the Mitochondrial Matrix of Saccharomyces cerevisiae. Front Mol Biosci 2017; 4:60. [PMID: 28879184 PMCID: PMC5572323 DOI: 10.3389/fmolb.2017.00060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/08/2017] [Indexed: 11/30/2022] Open
Abstract
ATPases associated with diverse cellular activities (AAA+) form a superfamily of proteins involved in a variety of functions and are characterized by the presence of an ATPase module containing two conserved motifs known as Walker A and Walker B. ClpB and Hsp104, chaperones that have disaggregase activities, are members of a subset of this superfamily, known as the AAA family, and are characterized by the presence of a second highly conserved motif, known as the second region of homology (SRH). Hsp104 and its homolog Hsp78 (78 kDa heat shock protein) are representatives of the Clp family in yeast. The structure and function of Hsp78 is reviewed and the possible existence of other homologs in metazoans is discussed.
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Affiliation(s)
| | - David Z Mokry
- Chemistry Institute, University of CampinasCampinas, Brazil
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16
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Duran EC, Weaver CL, Lucius AL. Comparative Analysis of the Structure and Function of AAA+ Motors ClpA, ClpB, and Hsp104: Common Threads and Disparate Functions. Front Mol Biosci 2017; 4:54. [PMID: 28824920 PMCID: PMC5540906 DOI: 10.3389/fmolb.2017.00054] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/13/2017] [Indexed: 11/25/2022] Open
Abstract
Cellular proteostasis involves not only the expression of proteins in response to environmental needs, but also the timely repair or removal of damaged or unneeded proteins. AAA+ motor proteins are critically involved in these pathways. Here, we review the structure and function of AAA+ proteins ClpA, ClpB, and Hsp104. ClpB and Hsp104 rescue damaged proteins from toxic aggregates and do not partner with any protease. ClpA functions as the regulatory component of the ATP dependent protease complex ClpAP, and also remodels inactive RepA dimers into active monomers in the absence of the protease. Because ClpA functions both with and without a proteolytic component, it is an ideal system for developing strategies that address one of the major challenges in the study of protein remodeling machines: how do we observe a reaction in which the substrate protein does not undergo covalent modification? Here, we review experimental designs developed for the examination of polypeptide translocation catalyzed by the AAA+ motors in the absence of proteolytic degradation. We propose that transient state kinetic methods are essential for the examination of elementary kinetic mechanisms of these motor proteins. Furthermore, rigorous kinetic analysis must also account for the thermodynamic properties of these complicated systems that reside in a dynamic equilibrium of oligomeric states, including the biologically active hexamer.
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Affiliation(s)
- Elizabeth C Duran
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
| | - Clarissa L Weaver
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
| | - Aaron L Lucius
- Department of Chemistry, University of Alabama at BirminghamBirmingham, AL, United States
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17
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Jackrel ME, Shorter J. Protein-Remodeling Factors As Potential Therapeutics for Neurodegenerative Disease. Front Neurosci 2017; 11:99. [PMID: 28293166 PMCID: PMC5328956 DOI: 10.3389/fnins.2017.00099] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/15/2017] [Indexed: 12/13/2022] Open
Abstract
Protein misfolding is implicated in numerous neurodegenerative disorders including amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington's disease. A unifying feature of patients with these disorders is the accumulation of deposits comprised of misfolded protein. Aberrant protein folding can cause toxicity through a loss or gain of protein function, or both. An intriguing therapeutic approach to counter these disorders is the application of protein-remodeling factors to resolve these misfolded conformers and return the proteins to their native fold and function. Here, we describe the application of protein-remodeling factors to alleviate protein misfolding in neurodegenerative disease. We focus on Hsp104, Hsp110/Hsp70/Hsp40, NMNAT, and HtrA1, which can prevent and reverse protein aggregation. While many of these protein-remodeling systems are highly promising, their activity can be limited. Thus, engineering protein-remodeling factors to enhance their activity could be therapeutically valuable. Indeed, engineered Hsp104 variants suppress neurodegeneration in animal models, which opens the way to novel therapeutics and mechanistic probes to help understand neurodegenerative disease.
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Affiliation(s)
- Meredith E Jackrel
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania Philadelphia, PA, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania Philadelphia, PA, USA
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18
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Kummer E, Szlachcic A, Franke KB, Ungelenk S, Bukau B, Mogk A. Bacterial and Yeast AAA + Disaggregases ClpB and Hsp104 Operate through Conserved Mechanism Involving Cooperation with Hsp70. J Mol Biol 2016; 428:4378-4391. [DOI: 10.1016/j.jmb.2016.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/10/2016] [Accepted: 09/06/2016] [Indexed: 11/28/2022]
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19
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Jackrel ME, Yee K, Tariq A, Chen AI, Shorter J. Disparate Mutations Confer Therapeutic Gain of Hsp104 Function. ACS Chem Biol 2015; 10:2672-9. [PMID: 26441009 DOI: 10.1021/acschembio.5b00765] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hsp104, a protein disaggregase from yeast, can be engineered and potentiated to counter TDP-43, FUS, or α-synuclein misfolding and toxicity implicated in neurodegenerative disease. Here, we reveal that extraordinarily disparate mutations potentiate Hsp104. Remarkably, diverse single missense mutations at 20 different positions interspersed throughout the middle domain (MD) and small domain of nucleotide-binding domain 1 (NBD1) confer a therapeutic gain of Hsp104 function. Moreover, potentiation emerges from deletion of MD helix 3 or 4 or via synergistic missense mutations in the MD distal loop and helix 4. We define the most critical aspect of Hsp104 potentiation as enhanced disaggregase activity in the absence of Hsp70 and Hsp40. We suggest that potentiation likely stems from a loss of a fragilely constrained autoinhibited state that enables precise spatiotemporal regulation of disaggregase activity.
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Affiliation(s)
- Meredith E. Jackrel
- Department of Biochemistry and Biophysics, ‡Cell and Molecular Biology Graduate
Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Keolamau Yee
- Department of Biochemistry and Biophysics, ‡Cell and Molecular Biology Graduate
Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Amber Tariq
- Department of Biochemistry and Biophysics, ‡Cell and Molecular Biology Graduate
Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Annie I. Chen
- Department of Biochemistry and Biophysics, ‡Cell and Molecular Biology Graduate
Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - James Shorter
- Department of Biochemistry and Biophysics, ‡Cell and Molecular Biology Graduate
Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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20
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Mechanistic and Structural Insights into the Prion-Disaggregase Activity of Hsp104. J Mol Biol 2015; 428:1870-85. [PMID: 26608812 DOI: 10.1016/j.jmb.2015.11.016] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/11/2015] [Accepted: 11/12/2015] [Indexed: 11/23/2022]
Abstract
Hsp104 is a dynamic ring translocase and hexameric AAA+ protein found in yeast, which couples ATP hydrolysis to disassembly and reactivation of proteins trapped in soluble preamyloid oligomers, disordered protein aggregates, and stable amyloid or prion conformers. Here, we highlight advances in our structural understanding of Hsp104 and how Hsp104 deconstructs Sup35 prions. Although the atomic structure of Hsp104 hexamers remains uncertain, volumetric reconstruction of Hsp104 hexamers in ATPγS, ADP-AlFx (ATP hydrolysis transition-state mimic), and ADP via small-angle x-ray scattering has revealed a peristaltic pumping motion upon ATP hydrolysis. This pumping motion likely drives directional substrate translocation across the central Hsp104 channel. Hsp104 initially engages Sup35 prions immediately C-terminal to their cross-β structure. Directional pulling by Hsp104 then resolves N-terminal cross-β structure in a stepwise manner. First, Hsp104 fragments the prion. Second, Hsp104 unfolds cross-β structure. Third, Hsp104 releases soluble Sup35. Deletion of the Hsp104 N-terminal domain yields a hypomorphic disaggregase, Hsp104(∆N), with an altered pumping mechanism. Hsp104(∆N) fragments Sup35 prions without unfolding cross-β structure or releasing soluble Sup35. Moreover, Hsp104(∆N) activity cannot be enhanced by mutations in the middle domain that potentiate disaggregase activity. Thus, the N-terminal domain is critical for the full repertoire of Hsp104 activities.
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21
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Molon M, Zadrag-Tecza R. Effect of temperature on replicative aging of the budding yeast Saccharomyces cerevisiae. Biogerontology 2015; 17:347-57. [PMID: 26481919 DOI: 10.1007/s10522-015-9619-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 10/09/2015] [Indexed: 11/28/2022]
Abstract
The use of the budding yeast Saccharomyces cerevisiae in gerontological studies was based on the assumption that the reproduction limit of a single cell (replicative aging) is a consequence of accumulation of a hypothetical universal "senescence factor" within the mother cell. However, some evidence suggests that molecules or structures proposed as the "aging factor", such as rDNA circles, oxidatively damaged proteins (with carbonyl groups) or mitochondria, have little effect on replicative lifespan of yeast cells. Our results also suggest that protein aggregates associated with Hsp104, treated as a marker of yeast aging, do not seem to affect the numeric value of replicative lifespan of yeast. What these results indicate, however, is the need for finding a different way of expressing age and longevity of yeast cells instead of the commonly used number of daughters produced over units of time, as in the case of other organisms. In this paper, we show that the temperature has a stronger influence on the time of life (the total lifespan) than on the reproductive potential of yeast cells.
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Affiliation(s)
- Mateusz Molon
- Department of Biochemistry and Cell Biology, University of Rzeszow, Zelwerowicza 4, 35-601, Rzeszow, Poland.
| | - Renata Zadrag-Tecza
- Department of Biochemistry and Cell Biology, University of Rzeszow, Zelwerowicza 4, 35-601, Rzeszow, Poland
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22
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Mokry DZ, Abrahão J, Ramos CH. Disaggregases, molecular chaperones that resolubilize protein aggregates. ACTA ACUST UNITED AC 2015; 87:1273-92. [DOI: 10.1590/0001-3765201520140671] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The process of folding is a seminal event in the life of a protein, as it is essential for proper protein function and therefore cell physiology. Inappropriate folding, or misfolding, can not only lead to loss of function, but also to the formation of protein aggregates, an insoluble association of polypeptides that harm cell physiology, either by themselves or in the process of formation. Several biological processes have evolved to prevent and eliminate the existence of non-functional and amyloidogenic aggregates, as they are associated with several human pathologies. Molecular chaperones and heat shock proteins are specialized in controlling the quality of the proteins in the cell, specifically by aiding proper folding, and dissolution and clearance of already formed protein aggregates. The latter is a function of disaggregases, mainly represented by the ClpB/Hsp104 subfamily of molecular chaperones, that are ubiquitous in all organisms but, surprisingly, have no orthologs in the cytosol of metazoan cells. This review aims to describe the characteristics of disaggregases and to discuss the function of yeast Hsp104, a disaggregase that is also involved in prion propagation and inheritance.
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Affiliation(s)
| | - Josielle Abrahão
- Universidade Estadual de Campinas, Brazil; Universidade Estadual de Campinas, Brazil
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23
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Affiliation(s)
- Ratnesh Chandra Mishra
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
| | - Anil Grover
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
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24
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25
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Torrente MP, Castellano LM, Shorter J. Suramin inhibits Hsp104 ATPase and disaggregase activity. PLoS One 2014; 9:e110115. [PMID: 25299406 PMCID: PMC4192545 DOI: 10.1371/journal.pone.0110115] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/17/2014] [Indexed: 12/16/2022] Open
Abstract
Hsp104 is a hexameric AAA+ protein that utilizes energy from ATP hydrolysis to dissolve disordered protein aggregates as well as amyloid fibers. Interestingly, Hsp104 orthologues are found in all kingdoms of life except animals. Thus, Hsp104 could represent an interesting drug target. Specific inhibition of Hsp104 activity might antagonize non-metazoan parasites that depend on a potent heat shock response, while producing little or no side effects to the host. However, no small molecule inhibitors of Hsp104 are known except guanidinium chloride. Here, we screen over 16,000 small molecules and identify 16 novel inhibitors of Hsp104 ATPase activity. Excluding compounds that inhibited Hsp104 activity by non-specific colloidal effects, we defined Suramin as an inhibitor of Hsp104 ATPase activity. Suramin is a polysulphonated naphthylurea and is used as an antiprotozoal drug for African Trypanosomiasis. Suramin also interfered with Hsp104 disaggregase, unfoldase, and translocase activities, and the inhibitory effect of Suramin was not rescued by Hsp70 and Hsp40. Suramin does not disrupt Hsp104 hexamers and does not effectively inhibit ClpB, the E. coli homolog of Hsp104, establishing yet another key difference between Hsp104 and ClpB behavior. Intriguingly, a potentiated Hsp104 variant, Hsp104A503V, is more sensitive to Suramin than wild-type Hsp104. By contrast, Hsp104 variants bearing inactivating sensor-1 mutations in nucleotide-binding domain (NBD) 1 or 2 are more resistant to Suramin. Thus, Suramin depends upon ATPase events at both NBDs to exert its maximal effect. Suramin could develop into an important mechanistic probe to study Hsp104 structure and function.
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Affiliation(s)
- Mariana P. Torrente
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Laura M. Castellano
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Pharmacology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - James Shorter
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Pharmacology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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26
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Bellaye PS, Burgy O, Causse S, Garrido C, Bonniaud P. Heat shock proteins in fibrosis and wound healing: Good or evil? Pharmacol Ther 2014; 143:119-32. [DOI: 10.1016/j.pharmthera.2014.02.009] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Accepted: 01/06/2014] [Indexed: 12/22/2022]
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27
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Jackrel ME, Shorter J. Potentiated Hsp104 variants suppress toxicity of diverse neurodegenerative disease-linked proteins. Dis Model Mech 2014; 7:1175-84. [PMID: 25062688 PMCID: PMC4174528 DOI: 10.1242/dmm.016113] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Protein misfolding is implicated in numerous lethal neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS) and Parkinson disease (PD). There are no therapies that reverse these protein-misfolding events. We aim to apply Hsp104, a hexameric AAA+ protein from yeast, to target misfolded conformers for reactivation. Hsp104 solubilizes disordered aggregates and amyloid, but has limited activity against human neurodegenerative disease proteins. Thus, we have previously engineered potentiated Hsp104 variants that suppress aggregation, proteotoxicity and restore proper protein localization of ALS and PD proteins in Saccharomyces cerevisiae, and mitigate neurodegeneration in an animal PD model. Here, we establish that potentiated Hsp104 variants possess broad substrate specificity and, in yeast, suppress toxicity and aggregation induced by wild-type TDP-43, FUS and α-synuclein, as well as missense mutant versions of these proteins that cause neurodegenerative disease. Potentiated Hsp104 variants also rescue toxicity and aggregation of TAF15 but not EWSR1, two RNA-binding proteins with a prion-like domain that are connected with the development of ALS and frontotemporal dementia. Thus, potentiated Hsp104 variants are not entirely non-specific. Indeed, they do not unfold just any natively folded protein. Rather, potentiated Hsp104 variants are finely tuned to unfold proteins bearing short unstructured tracts that are not recognized by wild-type Hsp104. Our studies establish the broad utility of potentiated Hsp104 variants.
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Affiliation(s)
- Meredith E Jackrel
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
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28
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Chaari A, Hoarau-Véchot J, Ladjimi M. Applying chaperones to protein-misfolding disorders: molecular chaperones against α-synuclein in Parkinson's disease. Int J Biol Macromol 2013; 60:196-205. [PMID: 23748003 DOI: 10.1016/j.ijbiomac.2013.05.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Revised: 05/28/2013] [Accepted: 05/29/2013] [Indexed: 02/04/2023]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the accumulation of a protein called α-synuclein (α-syn) into inclusions known as lewy bodies (LB) within neurons. This accumulation is also due to insufficient formation and activity of dopamine produced in certain neurons within the substantia nigra. Lewy bodies are the pathological hallmark of the idiopathic disorder and the cascade that allows α-synuclein to misfold, aggregate and form these inclusions has been the subject of intensive research. Targeting these early steps of oligomerization is one of the main therapeutic approaches in order to develop neurodegenerative-modifying agents. Because the folding and refolding of alpha synuclein is the key point of this cascade, we are interested in this review to summarize the role of some molecular chaperones proteins such as Hsp70, Hsp90 and small heat shock proteins (sHsp) and Hsp 104. Hsp70 and its co-chaperone, Hsp70 and small heat shock proteins can prevent neurodegeneration by preventing α-syn misfolding, oligomerization and aggregation in vitro and in Parkinson disease animal models. Hsp104 is able to resolve disordered protein aggregates and cross beta amyloid conformers. Together, these chaperones have a complementary effect and can be a target for therapeutic intervention in PD.
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Affiliation(s)
- Ali Chaari
- Department of Biochemistry, Weill Cornell Medical College in Qatar, Qatar Foundation, Education City, Doha, Qatar.
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29
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Sweeny EA, DeSantis ME, Shorter J. Purification of hsp104, a protein disaggregase. J Vis Exp 2011:3190. [PMID: 21989490 DOI: 10.3791/3190] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Hsp104 is a hexameric AAA+ protein(1) from yeast, which couples ATP hydrolysis to protein disaggregation (Fig. 1). This activity imparts two key selective advantages. First, renaturation of disordered aggregates by Hsp104 empowers yeast survival after various protein-misfolding stresses, including heat shock. Second, remodeling of cross-beta amyloid fibrils by Hsp104 enables yeast to exploit myriad prions (infectious amyloids) as a reservoir of beneficial and heritable phenotypic variation. Remarkably, Hsp104 directly remodels preamyloid oligomers and amyloid fibrils, including those comprised of the yeast prion proteins Sup35 and Ure2). This amyloid-remodeling functionality is a specialized facet of yeast Hsp104. The E. coli orthologue, ClpB, fails to remodel preamyloid oligomers or amyloid fibrils. Hsp104 orthologues are found in all kingdoms of life except, perplexingly, animals. Indeed, whether animal cells possess any enzymatic system that couples protein disaggregation to renaturation (rather than degradation) remains unknown. Thus, we and others have proposed that Hsp104 might be developed as a therapeutic agent for various neurodegenerative diseases connected with the misfolding of specific proteins into toxic preamyloid oligomers and amyloid fibrils. There are no treatments that directly target the aggregated species associated with these diseases. Yet, Hsp104 dissolves toxic oligomers and amyloid fibrils composed of alpha-synuclein, which are connected with Parkinson's Disease as well as amyloid forms of PrP. Importantly, Hsp104 reduces protein aggregation and ameliorates neurodegeneration in rodent models of Parkinson's Disease and Huntington's disease. Ideally, to optimize therapy and minimize side effects, Hsp104 would be engineered and potentiated to selectively remodel specific aggregates central to the disease in question. However, the limited structural and mechanistic understanding of how Hsp104 disaggregates such a diverse repertoire of aggregated structures and unrelated proteins frustrates these endeavors. To understand the structure and mechanism of Hsp104, it is essential to study the pure protein and reconstitute its disaggregase activity with minimal components. Hsp104 is a 102 kDa protein with a pI of -5.3, which hexamerizes in the presence of ADP or ATP, or at high protein concentrations in the absence of nucleotide. Here, we describe an optimized protocol for the purification of highly active, stable Hsp104 from E. coli. The use of E. coli allows simplified large-scale production and our method can be performed quickly and reliably for numerous Hsp104 variants. Our protocol increases Hsp104 purity and simplifies His(6)-tag removal compared to a previous purification method from E. coli. Moreover, our protocol is more facile and convenient than two more recent protocols.
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Affiliation(s)
- Elizabeth A Sweeny
- Department of Biochemistry and Biophysics, University of Pennsylvania, USA
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Sarkar S, Singh MD, Yadav R, Arunkumar KP, Pittman GW. Heat shock proteins: Molecules with assorted functions. ACTA ACUST UNITED AC 2011. [DOI: 10.1007/s11515-011-1080-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Desantis ME, Shorter J. The elusive middle domain of Hsp104 and ClpB: location and function. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1823:29-39. [PMID: 21843558 DOI: 10.1016/j.bbamcr.2011.07.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 07/13/2011] [Accepted: 07/18/2011] [Indexed: 12/17/2022]
Abstract
Hsp104 in yeast and ClpB in bacteria are homologous, hexameric AAA+ proteins and Hsp100 chaperones, which function in the stress response as ring-translocases that drive protein disaggregation and reactivation. Both Hsp104 and ClpB contain a distinctive coiled-coil middle domain (MD) inserted in the first AAA+ domain, which distinguishes them from other AAA+ proteins and Hsp100 family members. Here, we focus on recent developments concerning the location and function of the MD in these hexameric molecular machines, which remains an outstanding question. While the atomic structure of the hexameric assembly of Hsp104 and ClpB remains uncertain, recent advances have illuminated that the MD is critical for the intrinsic disaggregase activity of the hexamer and mediates key functional interactions with the Hsp70 chaperone system (Hsp70 and Hsp40) that empower protein disaggregation.
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Affiliation(s)
- Morgan E Desantis
- Department of Biochemistry and Biophysics, Perelman School of Medicine at The University of Pennsylvania, 805b Stellar-Chance Laboratories, 422 Curie Boulevard, Philadelphia, PA 19104, USA
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Franzmann TM, Czekalla A, Walter SG. Regulatory circuits of the AAA+ disaggregase Hsp104. J Biol Chem 2011; 286:17992-8001. [PMID: 21454552 DOI: 10.1074/jbc.m110.216176] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Yeast Hsp104 is an AAA+ chaperone that rescues proteins from the aggregated state. Six protomers associate to form the functional hexamer. Each protomer contains two AAA+ modules, NBD1 and NBD2. Hsp104 converts energy provided by ATP into mechanical force used to thread polypeptides through its axial channel, thereby disrupting protein aggregates. But how the action of its 12 AAA+ domains is co-ordinated to catalyze disaggregation remained unexplained. Here, we identify a sophisticated allosteric network consisting of three distinct pathways that senses the nucleotide state of AAA+ modules and transmits this information across the Hsp104 hexamer. As a result of this communication, NBD1 and NBD2 each adopt two distinct conformations (relaxed and tense) that are reciprocally regulated. The key element in the network is the NBD1-ATP state that enables Hsp104 to switch from a barely active [(T)(R)] state to a highly active [(R)(T)] state. This concerted switch involves both cis and trans protomer interactions and provides Hsp104 with the mechanistic scaffold to catalyze disaggregation. It prepares the chaperone for polypeptide binding and activates NBD2 to generate the power strokes required to resolve protein aggregates. ATP hydrolysis in NBD1 resolves the high affinity [(R)(T)] state and switches the chaperone back into the low affinity [(T)(R)] state. Our model integrates previously unexplained observations and provides the first comprehensive map of nucleotide-related allosteric signals in a class-1 AAA+ protein.
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Affiliation(s)
- Titus M Franzmann
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA
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Rubel AA, Saifitdinova AF, Lada AG, Nizhnikov AA, Inge-Vechtomov SG, Galkin AP. Yeast chaperone Hsp104 controls gene expression at the posttranscriptional level. Mol Biol 2011; 42:110-6. [DOI: 10.1134/s0026893308010160] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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[NSI (+)]: a novel non-Mendelian nonsense suppressor determinant in Saccharomyces cerevisiae. Curr Genet 2010; 56:467-78. [PMID: 20668856 DOI: 10.1007/s00294-010-0314-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 07/12/2010] [Accepted: 07/14/2010] [Indexed: 10/19/2022]
Abstract
Non-Mendelian determinants that control heritable traits in yeast are subdivided into two major groups-one that includes DNA- or RNA-based elements and another that comprises protein-based factors that are analogous to mammalian prion. All yeast non-Mendelian determinants show dominant inheritance, and some of them demonstrate cytoplasmic infectivity. Only prions, however, harbor-specific features, such as high frequency of induction following overproduction of prion-encoding protein, loss of the protein's normal function, and reversible curability. Here, we describe a novel nonchromosomal determinant that, in addition to [PSI (+)] and [ISP (+)], is involved in epigenetic control of nonsense suppression. This determinant, which we have designated [NSI (+)], causes nonsense suppression in the strains bearing the N-terminal-deleted or -modified SUP35 gene, but has no manifestation in the strains with the intact copy of SUP35. [NSI (+)] shows dominant non-Mendelian inheritance, reversible curability and may be transmitted by cytoduction, albeit with low frequency. Similar to yeast prions, this determinant can be cured by deletion or mutational inactivation of Hsp104. We have shown that [NSI (+)] does not correspond to the already identified yeast prions. Based on the data obtained, we hypothesize that [NSI (+)] is a novel prion factor involved in epigenetic control of nonsense suppression.
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Grimminger-Marquardt V, Lashuel HA. Structure and function of the molecular chaperone Hsp104 from yeast. Biopolymers 2010; 93:252-76. [PMID: 19768774 DOI: 10.1002/bip.21301] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The molecular chaperone Hsp104 plays a central role in the clearance of aggregates after heat shock and the propagation of yeast prions. Hsp104's disaggregation activity and prion propagation have been linked to its ability to resolubilize or remodel protein aggregates. However, Hsp104 has also the capacity to catalyze protein aggregation of some substrates at specific conditions. Hence, it is a molecular chaperone with two opposing activities with respect to protein aggregation. In yeast models of Huntington's disease, Hsp104 is required for the aggregation and toxicity of polyglutamine (polyQ), but the expression of Hsp104 in cellular and animal models of Huntington's and Parkinson's disease protects against polyQ and alpha-synuclein toxicity. Therefore, elucidating the molecular determinants and mechanisms underlying the ability of Hsp104 to switch between these two activities is of critical importance for understanding its function and could provide insight into novel strategies aimed at preventing or reversing the formation of toxic protein aggregation in systemic and neurodegenerative protein misfolding diseases. Here, we present an overview of the current molecular models and hypotheses that have been proposed to explain the role of Hsp104 in modulating protein aggregation and prion propagation. The experimental approaches and the evidences presented so far in relation to these models are examined. Our primary objective is to offer a critical review that will inspire the use of novel techniques and the design of new experiments to proceed towards a qualitative and quantitative understanding of the molecular mechanisms underlying the multifunctional properties of Hsp104 in vivo.
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Affiliation(s)
- Valerie Grimminger-Marquardt
- Laboratory of Molecular Neurobiology and Neuroproteomics, Swiss Federal Institute of Technology Lausanne (EPFL), FSV-BMI AI 2137.1, Station 15, CH-1015 Lausanne, Switzerland
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Sénéchal P, Arseneault G, Leroux A, Lindquist S, Rokeach LA. The Schizosaccharomyces pombe Hsp104 disaggregase is unable to propagate the [PSI] prion. PLoS One 2009; 4:e6939. [PMID: 19759825 PMCID: PMC2736384 DOI: 10.1371/journal.pone.0006939] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 08/05/2009] [Indexed: 11/19/2022] Open
Abstract
The molecular chaperone Hsp104 is a crucial factor in the acquisition of thermotolerance in yeast. Under stress conditions, the disaggregase activity of Hsp104 facilitates the reactivation of misfolded proteins. Hsp104 is also involved in the propagation of fungal prions. For instance, the well-characterized [PSI+] prion of Saccharomyces cerevisiae does not propagate in Δhsp104 cells or in cells overexpressing Hsp104. In this study, we characterized the functional homolog of Hsp104 from Schizosaccharomyces pombe (Sp_Hsp104). As its S. cerevisiae counterpart, Sp_hsp104+ is heat-inducible and required for thermotolerance in S. pombe. Sp_Hsp104 displays low disaggregase activity and cannot propagate the [PSI+] prion in S. cerevisiae. When overexpressed in S. cerevisiae, Sp_Hsp104 confers thermotolerance to Δhsp104 cells and reactivates heat-aggregated proteins. However, overexpression of Sp_Hsp104 does not propagate nor eliminate [PSI+]. Strikingly, [PSI+] was cured by overexpression of a chimeric chaperone bearing the C-terminal domain (CTD) of the S. cerevisiae Hsp104 protein. Our study demonstrates that the ability to untangle aggregated proteins is conserved between the S. pombe and S. cerevisiae Hsp104 homologs, and points to a role of the CTD in the propagation of the S. cerevisiae [PSI+] prion.
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Affiliation(s)
- Patrick Sénéchal
- Department of Biochemistry, Université de Montréal, Montréal, Québec, Canada
| | | | - Alexandre Leroux
- Department of Biochemistry, Université de Montréal, Montréal, Québec, Canada
| | - Susan Lindquist
- Whithead Institute for Biomedical Research and Howard Hughes Medical Institute, Cambridge Center, Cambridge, Massachusetts, United States of America
| | - Luis A. Rokeach
- Department of Biochemistry, Université de Montréal, Montréal, Québec, Canada
- * E-mail:
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Jóźwiak Z, Leyko W. Role of Membrane Components in Thermal Injury of Cells and Development of Thermotolerance. Int J Radiat Biol 2009; 62:743-56. [PMID: 1362768 DOI: 10.1080/09553009214552701] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Exposure of cells to hyperthermia induces a transient resistance to subsequent heat treatment. The specific mechanisms responsible for hyperthermic cell killing and thermotolerance development are not well understood. It seems that heat may induce at least two different states of thermotolerance, of which one is dependent on protein synthesis. The expression of thermotolerance may include multiple cytoplasmic and membrane components. A number of studies have indicated that membranes play an important role in governing the thermal injury of cells. It seems, therefore, that heat denatured plasma membrane proteins may be a potential target for thermal stress and a trigger for the induction of thermotolerance. The localization of heat shock proteins in the plasma membrane and the suggestion of thermal resistance in enucleate erythrocytes support this suggestion. However, a direct relationship between the plasma membrane and hyperthermic killing or development of thermotolerance has not been found.
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Affiliation(s)
- Z Jóźwiak
- Chair of Biophysics, University of Lódź, Poland
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38
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Doyle SM, Wickner S. Hsp104 and ClpB: protein disaggregating machines. Trends Biochem Sci 2008; 34:40-8. [PMID: 19008106 DOI: 10.1016/j.tibs.2008.09.010] [Citation(s) in RCA: 218] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 09/24/2008] [Accepted: 09/26/2008] [Indexed: 12/11/2022]
Abstract
Heat-shock protein 104 (Hsp104) and caseinolytic peptidase B (ClpB), members of the AAA+ superfamily, are molecular machines involved in disaggregating insoluble protein aggregates, a process not long ago thought to be impossible. During extreme stress they are essential for cell survival. In addition, Hsp104 regulates prion assembly and disassembly. For most of their protein remodeling activities Hsp104 and ClpB work in collaboration with the Hsp70 or DnaK chaperone systems. Together, the two chaperones catalyze protein disaggregation and reactivation by a mechanism probably involving the extraction of polypeptides from aggregates by forced unfolding and translocation through the Hsp104/ClpB central cavity. The polypeptides are then released back into the cellular milieu for spontaneous or chaperone-mediated refolding.
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Affiliation(s)
- Shannon M Doyle
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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39
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Lo Bianco C, Shorter J, Régulier E, Lashuel H, Iwatsubo T, Lindquist S, Aebischer P. Hsp104 antagonizes alpha-synuclein aggregation and reduces dopaminergic degeneration in a rat model of Parkinson disease. J Clin Invest 2008; 118:3087-97. [PMID: 18704197 DOI: 10.1172/jci35781] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 07/07/2008] [Indexed: 11/17/2022] Open
Abstract
Parkinson disease (PD) is characterized by dopaminergic neurodegeneration and intracellular inclusions of alpha-synuclein amyloid fibers, which are stable and difficult to dissolve. Whether inclusions are neuroprotective or pathological remains controversial, because prefibrillar oligomers may be more toxic than amyloid inclusions. Thus, whether therapies should target inclusions, preamyloid oligomers, or both is a critically important issue. In yeast, the protein-remodeling factor Hsp104 cooperates with Hsp70 and Hsp40 to dissolve and reactivate aggregated proteins. Metazoans, however, have no Hsp104 ortholog. Here we introduced Hsp104 into a rat PD model. Remarkably, Hsp104 reduced formation of phosphorylated alpha-synuclein inclusions and prevented nigrostriatal dopaminergic neurodegeneration induced by PD-linked alpha-synuclein (A30P). An in vitro assay employing pure proteins revealed that Hsp104 prevented fibrillization of alpha-synuclein and PD-linked variants (A30P, A53T, E46K). Hsp104 coupled ATP hydrolysis to the disassembly of preamyloid oligomers and amyloid fibers composed of alpha-synuclein. Furthermore, the mammalian Hsp70 and Hsp40 chaperones, Hsc70 and Hdj2, enhanced alpha-synuclein fiber disassembly by Hsp104. Hsp104 likely protects dopaminergic neurons by antagonizing toxic alpha-synuclein assemblies and might have therapeutic potential for PD and other neurodegenerative amyloidoses.
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Affiliation(s)
- Christophe Lo Bianco
- Wallenberg Neuroscience Center, Division of Neurobiology, Department of Experimental Medical Science, Lund University, Lund, Sweden
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41
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Panaretou B, Zhai C. The heat shock proteins: Their roles as multi-component machines for protein folding. FUNGAL BIOL REV 2008. [DOI: 10.1016/j.fbr.2009.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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42
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Malato L, Dos Reis S, Benkemoun L, Sabaté R, Saupe SJ. Role of Hsp104 in the propagation and inheritance of the [Het-s] prion. Mol Biol Cell 2007; 18:4803-12. [PMID: 17881723 PMCID: PMC2096600 DOI: 10.1091/mbc.e07-07-0657] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Revised: 09/05/2007] [Accepted: 09/10/2007] [Indexed: 11/11/2022] Open
Abstract
The chaperones of the ClpB/HSP100 family play a central role in thermotolerance in bacteria, plants, and fungi by ensuring solubilization of heat-induced protein aggregates. In addition in yeast, Hsp104 was found to be required for prion propagation. Herein, we analyze the role of Podospora anserina Hsp104 (PaHsp104) in the formation and propagation of the [Het-s] prion. We show that DeltaPaHsp104 strains propagate [Het-s], making [Het-s] the first native fungal prion to be propagated in the absence of Hsp104. Nevertheless, we found that [Het-s]-propagon numbers, propagation rate, and spontaneous emergence are reduced in a DeltaPaHsp104 background. In addition, inactivation of PaHsp104 leads to severe meiotic instability of [Het-s] and abolishes its meiotic drive activity. Finally, we show that DeltaPaHSP104 strains are less susceptible than wild type to infection by exogenous recombinant HET-s(218-289) prion amyloids. Like [URE3] and [PIN(+)] in yeast but unlike [PSI(+)], [Het-s] is not cured by constitutive PaHsp104 overexpression. The observed effects of PaHsp104 inactivation are consistent with the described role of Hsp104 in prion aggregate shearing in yeast. However, Hsp104-dependency appears less stringent in P. anserina than in yeast; presumably because in Podospora prion propagation occurs in a syncitium.
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Affiliation(s)
- Laurent Malato
- Laboratoire de Génétique Moléculaire des Champignons, Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095 Centre National de la Recherche Scientifique/Université de Bordeaux 2, 33077 Bordeaux Cedex, France
| | - Suzana Dos Reis
- Laboratoire de Génétique Moléculaire des Champignons, Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095 Centre National de la Recherche Scientifique/Université de Bordeaux 2, 33077 Bordeaux Cedex, France
| | - Laura Benkemoun
- Laboratoire de Génétique Moléculaire des Champignons, Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095 Centre National de la Recherche Scientifique/Université de Bordeaux 2, 33077 Bordeaux Cedex, France
| | - Raimon Sabaté
- Laboratoire de Génétique Moléculaire des Champignons, Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095 Centre National de la Recherche Scientifique/Université de Bordeaux 2, 33077 Bordeaux Cedex, France
| | - Sven J. Saupe
- Laboratoire de Génétique Moléculaire des Champignons, Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095 Centre National de la Recherche Scientifique/Université de Bordeaux 2, 33077 Bordeaux Cedex, France
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Doyle SM, Shorter J, Zolkiewski M, Hoskins JR, Lindquist S, Wickner S. Asymmetric deceleration of ClpB or Hsp104 ATPase activity unleashes protein-remodeling activity. Nat Struct Mol Biol 2007; 14:114-22. [PMID: 17259993 PMCID: PMC1793998 DOI: 10.1038/nsmb1198] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 01/02/2007] [Indexed: 11/09/2022]
Abstract
Two members of the AAA+ superfamily, ClpB and Hsp104, collaborate with Hsp70 and Hsp40 to rescue aggregated proteins. However, the mechanisms that elicit and underlie their protein-remodeling activities remain unclear. We report that for both Hsp104 and ClpB, mixtures of ATP and ATP-gammaS unexpectedly unleash activation, disaggregation and unfolding activities independent of cochaperones. Mutations reveal how remodeling activities are elicited by impaired hydrolysis at individual nucleotide-binding domains. However, for some substrates, mixtures of ATP and ATP-gammaS abolish remodeling, whereas for others, ATP binding without hydrolysis is sufficient. Remodeling of different substrates necessitates a diverse balance of polypeptide 'holding' (which requires ATP binding but not hydrolysis) and unfolding (which requires ATP hydrolysis). We suggest that this versatility in reaction mechanism enables ClpB and Hsp104 to reactivate the entire aggregated proteome after stress and enables Hsp104 to control prion inheritance.
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Affiliation(s)
- Shannon M. Doyle
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - James Shorter
- Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge MA 02142
| | - Michal Zolkiewski
- Department of Biochemistry, Kansas State University, Manhattan KS 66506, and
| | - Joel R. Hoskins
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge MA 02142
- Correspondence: Sue Wickner, , Susan Lindquist,
| | - Sue Wickner
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
- Correspondence: Sue Wickner, , Susan Lindquist,
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Takahashi A, Hara H, Kurahashi H, Nakamura Y. A systematic evaluation of the function of the protein-remodeling factor Hsp104 in [PSI+] prion propagation in S. cerevisiae by comprehensive chromosomal mutations. Prion 2007; 1:69-77. [PMID: 19164920 DOI: 10.4161/pri.1.1.4060] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The yeast prion [PSI(+)] represents an aggregated state of the translational release factor Sup35 (eRF3) and deprives termination complexes of functional Sup35, resulting in nonsense codon suppression. Protein-remodeling factor Hsp104 is involved in thermotolerance and [PSI(+)] propagation, however the structure-and-function relationship of Hsp104 for [PSI(+)] remains unclear. In this study, we engineered 58 chromosomal hsp104 mutants that affect residues considered structurally or functionally relevant to Hsp104 remodeling activity, yet most remain to be examined for their significance to [PSI(+)] in the same genetic background. Many of these hsp104 mutants were affected both in thermotolerance and [PSI(+)] propagation. However, nine mutants were impaired exclusively for [PSI(+)], while two mutants were impaired exclusively for thermotolerance. Mutations exclusively affecting [PSI(+)] are clustered around the lateral channel of the Hsp104 hexamer. These findings suggest that Hsp104 possesses shared as well as distinct remodeling activities for stress-induced protein aggregates and [PSI(+)] prion aggregates and that the lateral channel plays a role specific to [PSI(+)] prion propagation.
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Affiliation(s)
- Aiko Takahashi
- Department of Basic Medical Sciences, Institute of Medical Science, University of Tokyo, Tokyo, Japan
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Gashegu J, Vanmuylder N, Philippson C, Choa-Duterre M, Rooze M, Louryan S. Correlation of Hsp110 expression with caspase-3 and -9 during apoptosis induced by in vivo embryonic exposition to retinoic acid or irradiation in early mouse craniofacial development. Orthod Craniofac Res 2006; 9:84-92. [PMID: 16764683 DOI: 10.1111/j.1601-6343.2006.00361.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To analyze the expression and role of three proteins (HSP110, caspase-3 and caspase-9) during craniofacial development. DESIGN Seven pregnant C57Bl/6J mice received, by force-feeding at gestation day 9 (E9), 80 mg/kg of all-trans retinoic acid mixed to sesame oil. Seven pregnant NMRI mice received two grays irradiation at the same gestation day. Control mice of both strains (seven mice for each strain) were not submitted to any treatment. Embryos were obtained at various stages after exposition (3, 6, 12 and 24 h), fixed, dehydrated and embedded. Coronal sections (5 microm) were made. Slide staining occurred alternatively using anti-Hsp110, anti-caspase-3 and anti-caspase-9 immunohistochemistry. RESULTS Expression of HSP110, caspase-3 and caspase-9 was found in cells of well-known locations of programmed cell death. After retinoic acid exposure, expressions were increased especially in neural crest cells of mandibular and hyoid arches. Quantification of positive cells shows that caspase-9 and Hsp110 were expressed before caspase-3. After irradiation, the expression of the three proteins quickly increased with a maximum 3 h after irradiation. For all three models of apoptosis (physiological, retinoic-induced and irradiation-induced) HSP110 positive cells were more numerous than caspase-3 positive cells. Caspase-3 positive cells were more numerous than caspase-9 positive cells especially in mesectodermal irradiation-induced apoptotic cells. CONCLUSION The findings show a potential function of HSP110 in apoptosis during embryo development. Caspase-3-expressing cells are more numerous than cells expressing caspase-9, especially irradiation-induced apoptotic neural crest cells. This suggests that other caspases, still to be identified, may activate caspase-3 in this model.
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Affiliation(s)
- J Gashegu
- Laboratory of Human Anatomy and Embryology, Université Libre de Bruxelles, Faculté de Médecine, Brussels, Belgium
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Hung GC, Masison DC. N-terminal domain of yeast Hsp104 chaperone is dispensable for thermotolerance and prion propagation but necessary for curing prions by Hsp104 overexpression. Genetics 2006; 173:611-20. [PMID: 16582428 PMCID: PMC1526498 DOI: 10.1534/genetics.106.056820] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hsp104 is a hexameric protein chaperone that resolubilizes stress-damaged proteins from aggregates. Hsp104 promotes [PSI(+)] prion propagation by breaking prion aggregates, which propagate as amyloid fibers, into more numerous prion "seeds." Inactivating Hsp104 cures cells of [PSI(+)] and other amyloid-like yeast prions. Overexpressing Hsp104 also eliminates [PSI(+)], presumably by completely resolubilizing prion aggregates. Inexplicably, however, excess Hsp104 does not cure the other prions. Here we identify missense mutations in Hsp104's amino-terminal domain (NTD), which is conserved among Hsp100 proteins but whose function is unknown, that improve [PSI(+)] propagation. Hsp104Delta147, engineered to lack the NTD, supported [PSI(+)] and functioned normally in thermotolerance and protein disaggregation. Hsp104Delta147 failed to cure [PSI(+)] when overexpressed, however, implying that excess Hsp104 does not eliminate [PSI(+)] by direct dissolution of prion aggregates. Curing of [PSI(+)] by overexpressing catalytically inactive Hsp104 (Hsp104KT), which interferes with endogenous Hsp104, did not require the NTD. We further found that Hsp104 mutants defective in threading peptides through the hexamer pore had reduced ability to support [PSI(+)] in proportion to protein resolubilization defects, suggesting that [PSI(+)] propagation depends on this threading and that Hsp104 "breaks" prion aggregates by extracting protein monomers from the amyloid fibers.
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Affiliation(s)
- Guo-Chiuan Hung
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0851, USA
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Bösl B, Grimminger V, Walter S. The molecular chaperone Hsp104--a molecular machine for protein disaggregation. J Struct Biol 2006; 156:139-48. [PMID: 16563798 DOI: 10.1016/j.jsb.2006.02.004] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 02/06/2006] [Accepted: 02/09/2006] [Indexed: 11/25/2022]
Abstract
At the Cold Spring Harbor Meeting on 'Molecular Chaperones and the Heat Shock Response' in May 1996, Susan Lindquist presented evidence that a chaperone of yeast termed Hsp104, which her group had been investigating for several years, is able to dissolve protein aggregates (Glover, J.R., Lindquist, S., 1998. Hsp104, Hsp70, and Hsp40: a novel chaperone system that rescues previously aggregated proteins. Cell 94, 73-82). Among many of the participants this news stimulated reactions reaching from decided skepticism to utter disbelief because protein aggregation was widely considered to be an irreversible process. Several years and publications later, it is undeniable that Susan had been right. Hsp104 is an ATP dependent molecular machine that-in cooperation with Hsp70 and Hsp40-extracts polypeptide chains from protein aggregates and facilitates their refolding, although the molecular details of this process are still poorly understood. Meanwhile, close homologues of Hsp104 have been identified in bacteria (ClpB), in mitochondria (Hsp78), and in the cytosol of plants (Hsp101), but intriguingly not in the cytosol of animal cells (Mosser, D.D., Ho, S., Glover, J.R., 2004. Saccharomyces cerevisiae Hsp104 enhances the chaperone capacity of human cells and inhibits heat stress-induced proapoptotic signaling. Biochemistry 43, 8107-8115). Observations that Hsp104 plays an essential role in the maintenance of yeast prions (see review by James Shorter in this issue) have attracted even more attention to the molecular mechanism of this ATP dependent chaperone (Chernoff, Y.O., Lindquist, S.L., Ono, B., Inge-Vechtomov, S.G., Liebman, S.W., 1995. Role of the chaperone protein Hsp104 in propagation of the yeast prion-like factor [PSI+]. Science 268, 880-884).
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Affiliation(s)
- Benjamin Bösl
- Department für Chemie, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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Abstract
Exposure of yeast cells to environmental stresses can disrupt essential intracellular processes, especially those carried out by large macromolecular complexes. The production of mature, translatable mRNAs is most sensitive to stress owing to the inhibition of messenger RNA splicing and alterations in the export of mRNA from the nucleus. Changes in the cytoplasmic pools of mRNAs also occur following exposure to stress conditions. Messenger RNAs accumulate in discrete cytoplasmic foci such as processing bodies and stress granules. These dynamic changes in RNA metabolism, following exposure to stress, ensure the preferential production and export of heat-shock mRNAs and the sequestering of general cellular mRNAs in the nucleus or in cytoplasmic foci, thus allowing for a redirection of the translational machinery to encode stress proteins, which aid in cellular recovery following stress. Stress proteins, such as Hsp70p and Hsp104p, have been shown to play a direct role in the repair of macromolecular complexes involved in RNA metabolism in yeast cells, thus ensuring that the cell returns to homeostasis.
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Affiliation(s)
- Ursula Bond
- Microbiology Department, Moyne Institute for Preventive Medicine, Trinity College, University of Dublin, Dublin, Ireland.
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Camargos Oliveira J, Da Silva Castro N, Soares Felipe MS, Pereira M, De Almeida Soares CM. Comparative analysis of the cDNA encoding a ClpA homologue of Paracoccidioides brasiliensis. ACTA ACUST UNITED AC 2005; 109:707-16. [PMID: 16080393 DOI: 10.1017/s0953756205002789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A cDNA encoding a chaperone ClpA homologue of Paracoccidioides brasiliensis was isolated and characterized. The ClpA belongs to a group of ClpATPAses proteins, which are highly conserved, and include several heat inducible molecular chaperones. In this study, a 2879 bp cDNA designated as Pbclpa was obtained which encodes a predicted protein of 927 amino acids. Characteristic consensus motifs of the ClpATPases family are present. The PbClpA middle region was compared to other related ClpA and ClpB proteins from fungi and bacteria. Comparative analysis demonstrated in the middle region the presence of a heptad repeat sequence, characteristic of ClpBs from prokaryotes and fungi, which are absent in ClpAs from prokaryotes but were present in all described fungal ClpAs. Our comparative analysis reveals that one of the criteria typically used to distinguish the prokaryotic subfamilies ClpA and ClpB, the size of the middle sequence, may not be useful in fungi. Phylogenetic analyses were performed with the complete sequences of ClpAs from fungi and bacteria and with the middle regions of those ClpAs present at NCBI and Pfam databases. Our results indicated that both types of analysis can be useful as a tool in the determination of phylogenetic relationships.
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Affiliation(s)
- Juliana Camargos Oliveira
- Laboratório de Biologia Molecular, ICB, Universidade Federal de Goiás, 74.001-970, Goiânia, Goiás, Brazil
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Nag S, Das S, Chaudhuri K. In vivo induced clpB1 gene of Vibrio cholerae is involved in different stress responses and affects in vivo cholera toxin production. Biochem Biophys Res Commun 2005; 331:1365-73. [PMID: 15883026 DOI: 10.1016/j.bbrc.2005.04.052] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2005] [Indexed: 11/17/2022]
Abstract
Previously in global transcription profile approach one of the cosmid clones of Vibrio cholerae containing the genes pnuC, icmF, and a fragment of clpB2 showed higher expression in V. cholerae grown inside rabbit intestine. In the present report, both the stress responsive clpB genes of V. cholerae O395 were cloned, clpB1 from chromosome I and clpB2 present in chromosome II. From the Northern blot hybridization it was observed that the level of transcription of clpB2 was very low which could be due to the weak promoter strength of clpB2 as predicted in silico. The deduced amino acid sequence showed that clpB1 possesses features typical of the ClpB ATPase family of stress response proteins. The clpB1 gene showed about three times higher expression under in vivo condition than in vitro. Increased expression of clpB1 gene was also observed at high temperature, high salt, and in the condition mimicking human intestine viz., 37 degrees C, pH 8.5, 300 mM NaCl, which is known to be the repressive condition for ToxR, the global transcriptional regulator of virulence in V. cholerae. The clpB1 insertion mutant showed increased sensitivity towards high temperature, oxidative stress, and acid pH. ClpB1 also conferred thermotolerance to V. cholerae. These effects could be reversed by complementation. Although clpB1 appeared not to be under the control of virulence regulatory cascade of V. cholerae, the CT production was reduced in clpB1 mutant when tested in vivo in an infant mice model.
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Affiliation(s)
- Sanjay Nag
- Human Genetics and Genomics Group, Indian Institute of Chemical Biology, Jadavpur, Calcutta 700 032, India
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