1
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Lee G, Kim RS, Lee SB, Lee S, Tsai FT. Deciphering the mechanism and function of Hsp100 unfoldases from protein structure. Biochem Soc Trans 2022; 50:1725-1736. [PMID: 36454589 PMCID: PMC9784670 DOI: 10.1042/bst20220590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 12/02/2022]
Abstract
Hsp100 chaperones, also known as Clp proteins, constitute a family of ring-forming ATPases that differ in 3D structure and cellular function from other stress-inducible molecular chaperones. While the vast majority of ATP-dependent molecular chaperones promote the folding of either the nascent chain or a newly imported polypeptide to reach its native conformation, Hsp100 chaperones harness metabolic energy to perform the reverse and facilitate the unfolding of a misfolded polypeptide or protein aggregate. It is now known that inside cells and organelles, different Hsp100 members are involved in rescuing stress-damaged proteins from a previously aggregated state or in recycling polypeptides marked for degradation. Protein degradation is mediated by a barrel-shaped peptidase that physically associates with the Hsp100 hexamer to form a two-component system. Notable examples include the ClpA:ClpP (ClpAP) and ClpX:ClpP (ClpXP) proteases that resemble the ring-forming FtsH and Lon proteases, which unlike ClpAP and ClpXP, feature the ATP-binding and proteolytic domains in a single polypeptide chain. Recent advances in electron cryomicroscopy (cryoEM) together with single-molecule biophysical studies have now provided new mechanistic insight into the structure and function of this remarkable group of macromolecular machines.
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Affiliation(s)
- Grace Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Rice University, Houston, Texas 77005, USA
| | - Rebecca S. Kim
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Sang Bum Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Sukyeong Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Advanced Technology Core for Macromolecular X-ray Crystallography, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Francis T.F. Tsai
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Advanced Technology Core for Macromolecular X-ray Crystallography, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030, USA
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2
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Harari A, Zoltsman G, Levin T, Rosenzweig R. Hsp104 N-terminal domain interaction with substrates plays a regulatory role in protein disaggregation. FEBS J 2022; 289:5359-5377. [PMID: 35305079 PMCID: PMC9541529 DOI: 10.1111/febs.16441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/01/2022] [Accepted: 03/17/2022] [Indexed: 01/19/2023]
Abstract
Heat shock protein 104 (Hsp104) protein disaggregases are powerful molecular machines that harness the energy derived from ATP binding and hydrolysis to disaggregate a wide range of protein aggregates and amyloids, as well as to assist in yeast prion propagation. Little is known, however, about how Hsp104 chaperones recognize such a diversity of substrates, or indeed the contribution of the substrate‐binding N‐terminal domain (NTD) to Hsp104 function. Herein, we present a NMR spectroscopy study, which structurally characterizes the Hsp104 NTD‐substrate interaction. We show that the NTD includes a substrate‐binding groove that specifically recognizes exposed hydrophobic stretches in unfolded, misfolded, amyloid and prion substrates of Hsp104. In addition, we find that the NTD itself has chaperoning activities which help to protect the exposed hydrophobic regions of its substrates from further misfolding and aggregation, thereby priming them for threading through the Hsp104 central channel. We further demonstrate that mutations to this substrate‐binding groove abolish Hsp104 activation by client proteins and keep the chaperone in a partially inhibited state. The Hsp104 variant with these mutations also exhibited significantly reduced disaggregation activity and cell survival at extreme temperatures. Together, our findings provide both a detailed characterization of the NTD‐substrate complex and insight into the functional regulatory role of the NTD in protein disaggregation and yeast thermotolerance.
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Affiliation(s)
- Anna Harari
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Guy Zoltsman
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Tal Levin
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Rina Rosenzweig
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
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3
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Steele TE, Glynn SE. Mitochondrial AAA proteases: A stairway to degradation. Mitochondrion 2019; 49:121-127. [PMID: 31377246 DOI: 10.1016/j.mito.2019.07.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 07/31/2019] [Indexed: 12/22/2022]
Abstract
Mitochondrial protein quality control requires the action of proteases to remove damaged or unnecessary proteins and perform key regulatory cleavage events. Important components of the quality control network are the mitochondrial AAA proteases, which capture energy from ATP hydrolysis to destabilize and degrade protein substrates on both sides of the inner membrane. Dysfunction of these proteases leads to the breakdown of mitochondrial proteostasis and is linked to the development of severe human diseases. In this review, we will describe recent insights into the structure and motions of the mitochondrial AAA proteases and related enzymes. Together, these studies have revealed the mechanics of ATP-driven protein destruction and significantly advanced our understanding of how these proteases maintain mitochondrial health.
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Affiliation(s)
- Tyler E Steele
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA; Center for Structural Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Steven E Glynn
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA; Center for Structural Biology, Stony Brook University, Stony Brook, NY 11794, USA.
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4
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Guo P, Driver D, Zhao Z, Zheng Z, Chan C, Cheng X. Controlling the Revolving and Rotating Motion Direction of Asymmetric Hexameric Nanomotor by Arginine Finger and Channel Chirality. ACS NANO 2019; 13:6207-6223. [PMID: 31067030 PMCID: PMC6595433 DOI: 10.1021/acsnano.8b08849] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Nanomotors in nanotechnology are as important as engines in daily life. Many ATPases are nanoscale biomotors classified into three categories based on the motion mechanisms in transporting substrates: linear, rotating, and the recently discovered revolving motion. Most biomotors adopt a multisubunit ring-shaped structure that hydrolyzes ATP to generate force. How these biomotors control the motion direction and regulate the sequential action of their multiple subunits is intriguing. Many ATPases are hexameric with each monomer containing a conserved arginine finger. This review focuses on recent findings on how the arginine finger controls motion direction and coordinates adjacent subunit interactions in both revolving and rotating biomotors. Mechanisms of intersubunit interactions and sequential movements of individual subunits are evidenced by the asymmetrical appearance of one dimer and four monomers in high-resolution structural complexes. The arginine finger is situated at the interface of two subunits and extends into the ATP binding pocket of the downstream subunit. An arginine finger mutation results in deficiency in ATP binding/hydrolysis, substrate binding, and transport, highlighting the importance of the arginine finger in regulating energy transduction and motor function. Additionally, the roles of channel chirality and channel size are discussed as related to controlling one-way trafficking and differentiating the revolving and rotating mechanisms. Finally, the review concludes by discussing the conformational changes and entropy conversion triggered by ATP binding/hydrolysis, offering a view different from the traditional concept of ATP-mediated mechanochemical energy coupling. The elucidation of the motion mechanism and direction control in ATPases could facilitate nanomotor fabrication in nanotechnology.
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Affiliation(s)
- Peixuan Guo
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
- E-mail:
| | - Dana Driver
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Zhengyi Zhao
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Zhen Zheng
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Chun Chan
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
| | - Xiaolin Cheng
- Center
for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy
and College of Medicine, Dorothy M. Davis Heart and Lung Research
Institute, Comprehensive Cancer Center and College of Pharmacy, Biophysics
Graduate Program, Translational Data Analytics Institute, The Ohio State University, Columbus, Ohio 43210, United
States
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5
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Deville C, Franke K, Mogk A, Bukau B, Saibil HR. Two-Step Activation Mechanism of the ClpB Disaggregase for Sequential Substrate Threading by the Main ATPase Motor. Cell Rep 2019; 27:3433-3446.e4. [PMID: 31216466 PMCID: PMC6593972 DOI: 10.1016/j.celrep.2019.05.075] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 04/26/2019] [Accepted: 05/20/2019] [Indexed: 11/20/2022] Open
Abstract
AAA+ proteins form asymmetric hexameric rings that hydrolyze ATP and thread substrate proteins through a central channel via mobile substrate-binding pore loops. Understanding how ATPase and threading activities are regulated and intertwined is key to understanding the AAA+ protein mechanism. We studied the disaggregase ClpB, which contains tandem ATPase domains (AAA1, AAA2) and shifts between low and high ATPase and threading activities. Coiled-coil M-domains repress ClpB activity by encircling the AAA1 ring. Here, we determine the mechanism of ClpB activation by comparing ATPase mechanisms and cryo-EM structures of ClpB wild-type and a constitutively active ClpB M-domain mutant. We show that ClpB activation reduces ATPase cooperativity and induces a sequential mode of ATP hydrolysis in the AAA2 ring, the main ATPase motor. AAA1 and AAA2 rings do not work synchronously but in alternating cycles. This ensures high grip, enabling substrate threading via a processive, rope-climbing mechanism.
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Affiliation(s)
- Célia Deville
- Department of Crystallography, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Kamila Franke
- Center for Molecular Biology of University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Axel Mogk
- Center for Molecular Biology of University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
| | - Bernd Bukau
- Center for Molecular Biology of University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
| | - Helen R Saibil
- Department of Crystallography, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK.
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6
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Structural determinants for protein unfolding and translocation by the Hsp104 protein disaggregase. Biosci Rep 2017; 37:BSR20171399. [PMID: 29175998 PMCID: PMC5741831 DOI: 10.1042/bsr20171399] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/17/2017] [Accepted: 11/22/2017] [Indexed: 01/23/2023] Open
Abstract
The ring-forming Hsp104 ATPase cooperates with Hsp70 and Hsp40 molecular chaperones to rescue stress-damaged proteins from both amorphous and amyloid-forming aggregates. The ability to do so relies upon pore loops present in the first ATP-binding domain (AAA-1; loop-1 and loop-2 ) and in the second ATP-binding domain (AAA-2; loop-3) of Hsp104, which face the protein translocating channel and couple ATP-driven changes in pore loop conformation to substrate translocation. A hallmark of loop-1 and loop-3 is an invariable and mutational sensitive aromatic amino acid (Tyr257 and Tyr662) involved in substrate binding. However, the role of conserved aliphatic residues (Lys256, Lys258, and Val663) flanking the pore loop tyrosines, and the function of loop-2 in protein disaggregation has not been investigated. Here we present the crystal structure of an N-terminal fragment of Saccharomyces cerevisiae Hsp104 exhibiting molecular interactions involving both AAA-1 pore loops, which resemble contacts with bound substrate. Corroborated by biochemical experiments and functional studies in yeast, we show that aliphatic residues flanking Tyr257 and Tyr662 are equally important for substrate interaction, and abolish Hsp104 function when mutated to glycine. Unexpectedly, we find that loop-2 is sensitive to aspartate substitutions that impair Hsp104 function and abolish protein disaggregation when loop-2 is replaced by four aspartate residues. Our observations suggest that Hsp104 pore loops have non-overlapping functions in protein disaggregation and together coordinate substrate binding, unfolding, and translocation through the Hsp104 hexamer.
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7
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Overlapping and Specific Functions of the Hsp104 N Domain Define Its Role in Protein Disaggregation. Sci Rep 2017; 7:11184. [PMID: 28894176 PMCID: PMC5593927 DOI: 10.1038/s41598-017-11474-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 08/21/2017] [Indexed: 11/08/2022] Open
Abstract
Hsp104 is a ring-forming protein disaggregase that rescues stress-damaged proteins from an aggregated state. To facilitate protein disaggregation, Hsp104 cooperates with Hsp70 and Hsp40 chaperones (Hsp70/40) to form a bi-chaperone system. How Hsp104 recognizes its substrates, particularly the importance of the N domain, remains poorly understood and multiple, seemingly conflicting mechanisms have been proposed. Although the N domain is dispensable for protein disaggregation, it is sensitive to point mutations that abolish the function of the bacterial Hsp104 homolog in vitro, and is essential for curing yeast prions by Hsp104 overexpression in vivo. Here, we present the crystal structure of an N-terminal fragment of Saccharomyces cerevisiae Hsp104 with the N domain of one molecule bound to the C-terminal helix of the neighboring D1 domain. Consistent with mimicking substrate interaction, mutating the putative substrate-binding site in a constitutively active Hsp104 variant impairs the recovery of functional protein from aggregates. We find that the observed substrate-binding defect can be rescued by Hsp70/40 chaperones, providing a molecular explanation as to why the N domain is dispensable for protein disaggregation when Hsp70/40 is present, yet essential for the dissolution of Hsp104-specific substrates, such as yeast prions, which likely depends on a direct N domain interaction.
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8
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Franke KB, Bukau B, Mogk A. Mutant Analysis Reveals Allosteric Regulation of ClpB Disaggregase. Front Mol Biosci 2017; 4:6. [PMID: 28275610 PMCID: PMC5319980 DOI: 10.3389/fmolb.2017.00006] [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: 12/22/2016] [Accepted: 02/07/2017] [Indexed: 11/13/2022] Open
Abstract
The members of the hexameric AAA+ disaggregase of E. coli and S. cerevisiae, ClpB, and Hsp104, cooperate with the Hsp70 chaperone system in the solubilization of aggregated proteins. Aggregate solubilization relies on a substrate threading activity of ClpB/Hsp104 fueled by ATP hydrolysis in both ATPase rings (AAA-1, AAA-2). ClpB/Hsp104 ATPase activity is controlled by the M-domains, which associate to the AAA-1 ring to downregulate ATP hydrolysis. Keeping M-domains displaced from the AAA-1 ring by association with Hsp70 increases ATPase activity due to enhanced communication between protomers. This communication involves conserved arginine fingers. The control of ClpB/Hsp104 activity is crucial, as hyperactive mutants with permanently dissociated M-domains exhibit cellular toxicity. Here, we analyzed AAA-1 inter-ring communication in relation to the M-domain mediated ATPase regulation, by subjecting a conserved residue of the AAA-1 domain subunit interface of ClpB (A328) to mutational analysis. While all A328X mutants have reduced disaggregation activities, their ATPase activities strongly differed. ClpB-A328I/L mutants have reduced ATPase activity and when combined with the hyperactive ClpB-K476C M-domain mutation, suppress cellular toxicity. This underlines that ClpB ATPase activation by M-domain dissociation relies on increased subunit communication. The ClpB-A328V mutant in contrast has very high ATPase activity and exhibits cellular toxicity on its own, qualifying it as novel hyperactive ClpB mutant. ClpB-A328V hyperactivity is however, different from that of M-domain mutants as M-domains stay associated with the AAA-1 ring. The high ATPase activity of ClpB-A328V primarily relies on the AAA-2 ring and correlates with distinct conformational changes in the AAA-2 catalytic site. These findings characterize the subunit interface residue A328 as crucial regulatory element to control ATP hydrolysis in both AAA rings.
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Affiliation(s)
- Kamila B Franke
- Center for Molecular Biology of the Heidelberg University, German Cancer Research Center Heidelberg, Germany
| | - Bernd Bukau
- Center for Molecular Biology of the Heidelberg University, German Cancer Research Center Heidelberg, Germany
| | - Axel Mogk
- Center for Molecular Biology of the Heidelberg University, German Cancer Research Center Heidelberg, Germany
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9
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Heuck A, Schitter-Sollner S, Suskiewicz MJ, Kurzbauer R, Kley J, Schleiffer A, Rombaut P, Herzog F, Clausen T. Structural basis for the disaggregase activity and regulation of Hsp104. eLife 2016; 5. [PMID: 27901467 PMCID: PMC5130295 DOI: 10.7554/elife.21516] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/22/2016] [Indexed: 11/13/2022] Open
Abstract
The Hsp104 disaggregase is a two-ring ATPase machine that rescues various forms of non-native proteins including the highly resistant amyloid fibers. The structural-mechanistic underpinnings of how the recovery of toxic protein aggregates is promoted and how this potent unfolding activity is prevented from doing collateral damage to cellular proteins are not well understood. Here, we present structural and biochemical data revealing the organization of Hsp104 from Chaetomium thermophilum at 3.7 Å resolution. We show that the coiled-coil domains encircling the disaggregase constitute a ‘restraint mask’ that sterically controls the mobility and thus the unfolding activity of the ATPase modules. In addition, we identify a mechanical linkage that coordinates the activity of the two ATPase rings and accounts for the high unfolding potential of Hsp104. Based on these findings, we propose a general model for how Hsp104 and related chaperones operate and are kept under control until recruited to appropriate substrates. DOI:http://dx.doi.org/10.7554/eLife.21516.001
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Affiliation(s)
- Alexander Heuck
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | | | | | - Robert Kurzbauer
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - Juliane Kley
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | | | - Pascaline Rombaut
- Gene Center and Department of Biochemistry, Ludwig-Maximilians University, Munich, Germany
| | - Franz Herzog
- Gene Center and Department of Biochemistry, Ludwig-Maximilians University, Munich, Germany
| | - Tim Clausen
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
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10
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Sung N, Lee J, Kim JH, Chang C, Tsai FTF, Lee S. 2.4 Å resolution crystal structure of human TRAP1NM, the Hsp90 paralog in the mitochondrial matrix. Acta Crystallogr D Struct Biol 2016; 72:904-11. [PMID: 27487821 PMCID: PMC4973209 DOI: 10.1107/s2059798316009906] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/17/2016] [Indexed: 11/10/2022] Open
Abstract
TRAP1 is an organelle-specific Hsp90 paralog that is essential for neoplastic growth. As a member of the Hsp90 family, TRAP1 is presumed to be a general chaperone facilitating the late-stage folding of Hsp90 client proteins in the mitochondrial matrix. Interestingly, TRAP1 cannot replace cytosolic Hsp90 in protein folding, and none of the known Hsp90 co-chaperones are found in mitochondria. Thus, the three-dimensional structure of TRAP1 must feature regulatory elements that are essential to the ATPase activity and chaperone function of TRAP1. Here, the crystal structure of a human TRAP1NM dimer is presented, featuring an intact N-domain and M-domain structure, bound to adenosine 5'-β,γ-imidotriphosphate (ADPNP). The crystal structure together with epitope-mapping results shows that the TRAP1 M-domain loop 1 contacts the neighboring subunit and forms a previously unobserved third dimer interface that mediates the specific interaction with mitochondrial Hsp70.
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Affiliation(s)
- Nuri Sung
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jungsoon Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ji-Hyun Kim
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Changsoo Chang
- Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Francis T. F. Tsai
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sukyeong Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
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11
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Mogk A, Kummer E, Bukau B. Cooperation of Hsp70 and Hsp100 chaperone machines in protein disaggregation. Front Mol Biosci 2015; 2:22. [PMID: 26042222 PMCID: PMC4436881 DOI: 10.3389/fmolb.2015.00022] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 05/04/2015] [Indexed: 11/13/2022] Open
Abstract
Unicellular and sessile organisms are particularly exposed to environmental stress such as heat shock causing accumulation and aggregation of misfolded protein species. To counteract protein aggregation, bacteria, fungi, and plants encode a bi-chaperone system composed of ATP-dependent Hsp70 and hexameric Hsp100 (ClpB/Hsp104) chaperones, which rescue aggregated proteins and provide thermotolerance to cells. The partners act in a hierarchic manner with Hsp70 chaperones coating first the surface of protein aggregates and next recruiting Hsp100 through direct physical interaction. Hsp100 proteins bind to the ATPase domain of Hsp70 via their unique M-domain. This extra domain functions as a molecular toggle allosterically controlling ATPase and threading activities of Hsp100. Interactions between neighboring M-domains and the ATPase ring keep Hsp100 in a repressed state exhibiting low ATP turnover. Breakage of intermolecular M-domain interactions and dissociation of M-domains from the ATPase ring relieves repression and allows for Hsp70 interaction. Hsp70 binding in turn stabilizes Hsp100 in the activated state and primes Hsp100 ATPase domains for high activity upon substrate interaction. Hsp70 thereby couples Hsp100 substrate binding and motor activation. Hsp100 activation presumably relies on increased subunit cooperation leading to high ATP turnover and threading power. This Hsp70-mediated activity control of Hsp100 is crucial for cell viability as permanently activated Hsp100 variants are toxic. Hsp100 activation requires simultaneous binding of multiple Hsp70 partners, restricting high Hsp100 activity to the surface of protein aggregates and ensuring Hsp100 substrate specificity.
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Affiliation(s)
- Axel Mogk
- Center for Molecular Biology of the University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance Heidelberg, Germany
| | - Eva Kummer
- Center for Molecular Biology of the University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance Heidelberg, Germany
| | - Bernd Bukau
- Center for Molecular Biology of the University of Heidelberg (ZMBH) and German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance Heidelberg, Germany
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12
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Jeng W, Lee S, Sung N, Lee J, Tsai FT. Molecular chaperones: guardians of the proteome in normal and disease states. F1000Res 2015; 4:F1000 Faculty Rev-1448. [PMID: 26918154 PMCID: PMC4754035 DOI: 10.12688/f1000research.7214.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/11/2015] [Indexed: 12/31/2022] Open
Abstract
Proteins must adopt a defined three-dimensional structure in order to gain functional activity, or must they? An ever-increasing number of intrinsically disordered proteins and amyloid-forming polypeptides challenge this dogma. While molecular chaperones and proteases are traditionally associated with protein quality control inside the cell, it is now apparent that molecular chaperones not only promote protein folding in the "forward" direction by facilitating folding and preventing misfolding and aggregation, but also facilitate protein unfolding and even disaggregation resulting in the recovery of functional protein from aggregates. Here, we review our current understanding of ATP-dependent molecular chaperones that harness the energy of ATP binding and hydrolysis to fuel their chaperone functions. An emerging theme is that most of these chaperones do not work alone, but instead function together with other chaperone systems to maintain the proteome. Hence, molecular chaperones are the major component of the proteostasis network that guards and protects the proteome from damage. Furthermore, while a decline of this network is detrimental to cell and organismal health, a controlled perturbation of the proteostasis network may offer new therapeutic avenues against human diseases.
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Affiliation(s)
- Wilson Jeng
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Sukyeong Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Nuri Sung
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Jungsoon Lee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Francis T.F. Tsai
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
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13
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Zeymer C, Fischer S, Reinstein J. trans-Acting arginine residues in the AAA+ chaperone ClpB allosterically regulate the activity through inter- and intradomain communication. J Biol Chem 2014; 289:32965-76. [PMID: 25253689 PMCID: PMC4239642 DOI: 10.1074/jbc.m114.608828] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The molecular chaperone ClpB/Hsp104, a member of the AAA+ superfamily (ATPases associated with various cellular activities), rescues proteins from the aggregated state in collaboration with the DnaK/Hsp70 chaperone system. ClpB/Hsp104 forms a hexameric, ring-shaped complex that functions as a tightly regulated, ATP-powered molecular disaggregation machine. Highly conserved and essential arginine residues, often called arginine fingers, are located at the subunit interfaces of the complex, which also harbor the catalytic sites. Several AAA+ proteins, including ClpB/Hsp104, possess a pair of such trans-acting arginines in the N-terminal nucleotide binding domain (NBD1), both of which were shown to be crucial for oligomerization and ATPase activity. Here, we present a mechanistic study elucidating the role of this conserved arginine pair. First, we found that the arginines couple nucleotide binding to oligomerization of NBD1, which is essential for the activity. Next, we designed a set of covalently linked, dimeric ClpB NBD1 variants, carrying single subunits deficient in either ATP binding or hydrolysis, to study allosteric regulation and intersubunit communication. Using this well defined environment of site-specifically modified, cross-linked AAA+ domains, we found that the conserved arginine pair mediates the cooperativity of ATP binding and hydrolysis in an allosteric fashion.
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Affiliation(s)
- Cathleen Zeymer
- From the Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Sebastian Fischer
- From the Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Jochen Reinstein
- From the Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
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Carroni M, Kummer E, Oguchi Y, Wendler P, Clare DK, Sinning I, Kopp J, Mogk A, Bukau B, Saibil HR. Head-to-tail interactions of the coiled-coil domains regulate ClpB activity and cooperation with Hsp70 in protein disaggregation. eLife 2014; 3:e02481. [PMID: 24843029 PMCID: PMC4023160 DOI: 10.7554/elife.02481] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The hexameric AAA+ chaperone ClpB reactivates aggregated proteins in cooperation with the Hsp70 system. Essential for disaggregation, the ClpB middle domain (MD) is a coiled-coil propeller that binds Hsp70. Although the ClpB subunit structure is known, positioning of the MD in the hexamer and its mechanism of action are unclear. We obtained electron microscopy (EM) structures of the BAP variant of ClpB that binds the protease ClpP, clearly revealing MD density on the surface of the ClpB ring. Mutant analysis and asymmetric reconstructions show that MDs adopt diverse positions in a single ClpB hexamer. Adjacent, horizontally oriented MDs form head-to-tail contacts and repress ClpB activity by preventing Hsp70 interaction. Tilting of the MD breaks this contact, allowing Hsp70 binding, and releasing the contact in adjacent subunits. Our data suggest a wavelike activation of ClpB subunits around the ring.DOI: http://dx.doi.org/10.7554/eLife.02481.001.
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Affiliation(s)
- Marta Carroni
- Department of Crystallography, Birkbeck College, University of London, London, United Kingdom
| | - Eva Kummer
- Zentrum für Molekulare Biologie, Universität Heidelberg, Heidelberg, Germany
| | - Yuki Oguchi
- Zentrum für Molekulare Biologie, Universität Heidelberg, Heidelberg, Germany
| | - Petra Wendler
- Gene Center, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Daniel K Clare
- Department of Crystallography, Birkbeck College, University of London, London, United Kingdom
| | - Irmgard Sinning
- Biochemie-Zentrum, Universität Heidelberg, Heidelberg, Germany
| | - Jürgen Kopp
- Biochemie-Zentrum, Universität Heidelberg, Heidelberg, Germany
| | - Axel Mogk
- Zentrum für Molekulare Biologie, Universität Heidelberg, Heidelberg, Germany
| | - Bernd Bukau
- Zentrum für Molekulare Biologie, Universität Heidelberg, Heidelberg, Germany
| | - Helen R Saibil
- Department of Crystallography, Birkbeck College, University of London, London, United Kingdom
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15
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Dulle JE, Stein KC, True HL. Regulation of the Hsp104 middle domain activity is critical for yeast prion propagation. PLoS One 2014; 9:e87521. [PMID: 24466354 PMCID: PMC3900729 DOI: 10.1371/journal.pone.0087521] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 12/21/2013] [Indexed: 11/19/2022] Open
Abstract
Molecular chaperones play a significant role in preventing protein misfolding and aggregation. Indeed, some protein conformational disorders have been linked to changes in the chaperone network. Curiously, in yeast, chaperones also play a role in promoting prion maintenance and propagation. While many amyloidogenic proteins are associated with disease in mammals, yeast prion proteins, and their ability to undergo conformational conversion into a prion state, are proposed to play a functional role in yeast biology. The chaperone Hsp104, a AAA+ ATPase, is essential for yeast prion propagation. Hsp104 fragments large prion aggregates to generate a population of smaller oligomers that can more readily convert soluble monomer and be transmitted to daughter cells. Here, we show that the middle (M) domain of Hsp104, and its mobility, plays an integral part in prion propagation. We generated and characterized mutations in the M-domain of Hsp104 that are predicted to stabilize either a repressed or de-repressed conformation of the M-domain (by analogy to ClpB in bacteria). We show that the predicted stabilization of the repressed conformation inhibits general chaperone activity. Mutation to the de-repressed conformation, however, has differential effects on ATP hydrolysis and disaggregation, suggesting that the M-domain is involved in coupling these two activities. Interestingly, we show that changes in the M-domain differentially affect the propagation of different variants of the [PSI+] and [RNQ+] prions, which indicates that some prion variants are more sensitive to changes in the M-domain mobility than others. Thus, we provide evidence that regulation of the M-domain of Hsp104 is critical for efficient prion propagation. This shows the importance of elucidating the function of the M-domain in order to understand the role of Hsp104 in the propagation of different prions and prion variants.
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Affiliation(s)
- Jennifer E. Dulle
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Kevin C. Stein
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Heather L. True
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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16
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Abstract
Heat shock protein (Hsp) 104 is a ring-forming, protein-remodeling machine that harnesses the energy of ATP binding and hydrolysis to drive protein disaggregation. Although Hsp104 is an active ATPase, the recovery of functional protein requires the species-specific cooperation of the Hsp70 system. However, like Hsp104, Hsp70 is an active ATPase, which recognizes aggregated and aggregation-prone proteins, making it difficult to differentiate the mechanistic roles of Hsp104 and Hsp70 during protein disaggregation. Mapping the Hsp70-binding sites in yeast Hsp104 using peptide array technology and photo-cross-linking revealed a striking conservation of the primary Hsp70-binding motifs on the Hsp104 middle-domain across species, despite lack of sequence identity. Remarkably, inserting a Strep-Tactin binding motif at the spatially conserved Hsp70-binding site elicits the Hsp104 protein disaggregating activity that now depends on Strep-Tactin but no longer requires Hsp70/40. Consistent with a Strep-Tactin-dependent activation step, we found that full-length Hsp70 on its own could activate the Hsp104 hexamer by promoting intersubunit coordination, suggesting that Hsp70 is an activator of the Hsp104 motor.
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Kim Y, Park JH, Jang JY, Rhim H, Kang S. Characterization and Hsp104-induced artificial clearance of familial ALS-related SOD1 aggregates. Biochem Biophys Res Commun 2013; 434:521-6. [PMID: 23583391 DOI: 10.1016/j.bbrc.2013.03.107] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 03/20/2013] [Indexed: 12/27/2022]
Abstract
Hsp104, a molecular chaperone protein, originates from Saccharomyces cerevisiae and shows potential for development as a therapeutic disaggregase for the treatment of neurodegenerative disorders. This study shows that aggregates of mutant superoxide dismutase 1 (SOD1), which cause amyotrophic lateral sclerosis (ALS), are disaggregated by Hsp104 in an ATP-dependent manner. Mutant SOD1 aggregates were first characterized using fluorescence loss in photobleaching experiments based on the reduced mobility of aggregated proteins. Hsp104 restored the mobility of mutant SOD1 proteins to a level comparable with that of the wild-type. However, ATPase-deficient Hsp104 mutants did not restore mobility, suggesting that, rather than preventing aggregation, Hsp104 disaggregates mutant SOD1 after it has aggregated. Despite the restored mobility, however, mutant SOD1 proteins existed as trimers or other higher-order structures, rather than as naturally occurring dimers. This study sheds further light on the mechanisms underlying the disaggregation of SOD1 mutant aggregates in ALS.
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Affiliation(s)
- Yongmin Kim
- Division of Life Sciences, Korea University, Seoul 136-701, South Korea
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