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Ulmer LD, Canzani D, Woods CN, Stone NL, Janowska MK, Klevit RE, Bush MF. High-Performance Workflow for Identifying Site-Specific Crosslinks Originating from a Genetically Incorporated, Photoreactive Amino Acid. J Proteome Res 2024; 23:3560-3570. [PMID: 38968604 PMCID: PMC11296897 DOI: 10.1021/acs.jproteome.4c00194] [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] [Indexed: 07/07/2024]
Abstract
In conventional crosslinking mass spectrometry, proteins are crosslinked using a highly selective, bifunctional chemical reagent, which limits crosslinks to residues that are accessible and reactive to the reagent. Genetically incorporating a photoreactive amino acid offers two key advantages: any site can be targeted, including those that are inaccessible to conventional crosslinking reagents, and photoreactive amino acids can potentially react with a broad range of interaction partners. However, broad reactivity imposes additional challenges for crosslink identification. In this study, we incorporate benzoylphenylalanine (BPA), a photoreactive amino acid, at selected sites in an intrinsically disordered region of the human protein HSPB5. We report and characterize a workflow for identifying and visualizing residue-level interactions originating from BPA. We routinely identify 30 to 300 crosslinked peptide spectral matches with this workflow, which is up to ten times more than existing tools for residue-level BPA crosslink identification. Most identified crosslinks are assigned to a precision of one or two residues, which is supported by a high degree of overlap between replicate analyses. Based on these results, we anticipate that this workflow will support the more general use of genetically incorporated, photoreactive amino acids for characterizing the structures of proteins that have resisted high-resolution characterization.
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Affiliation(s)
- Lindsey D. Ulmer
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Daniele Canzani
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Christopher N. Woods
- University of Washington, Department of Biochemistry, Box 357350, Seattle, WA 98195-7350
| | - Natalie L. Stone
- University of Washington, Department of Biochemistry, Box 357350, Seattle, WA 98195-7350
| | - Maria K. Janowska
- University of Washington, Department of Biochemistry, Box 357350, Seattle, WA 98195-7350
| | - Rachel E. Klevit
- University of Washington, Department of Biochemistry, Box 357350, Seattle, WA 98195-7350
| | - Matthew F. Bush
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
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2
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Nasiri F, Ebrahimi P, Shahsavani MB, Barati A, Zarei I, Hong J, Hoshino M, Moosavi-Movahedi AA, Yousefi R. Unraveling the impact of the p.R107L mutation on the structure and function of human αB-Crystallin: Implications for cataract formation. Biochimie 2024; 222:151-168. [PMID: 38494110 DOI: 10.1016/j.biochi.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/01/2024] [Accepted: 03/04/2024] [Indexed: 03/19/2024]
Abstract
To date, several pathogenic mutations have been identified in the primary structure of human α-Crystallin, frequently involving the substitution of arginine with a different amino acid. These mutations can lead to the incidence of cataracts and myopathy. Recently, an important cataract-associated mutation has been reported in the functional α-Crystallin domain (ACD) of human αB-Crystallin protein, where arginine 107 (R107) is replaced by a leucine. In this study, we investigated the structure, chaperone function, stability, oligomerization, and amyloidogenic properties of the p.R107L human αB-Crystallin using a number of different techniques. Our results suggest that the p.R107L mutation can cause significant changes in the secondary, tertiary, and quaternary structures of αB-Crystallin. This cataractogenic mutation led to the formation of protein oligomers with larger sizes than the wild-type protein and reduced the chemical and thermal stability of the mutant chaperone. Both fluorescence and microscopic assessments indicated that this mutation significantly altered the amyloidogenic properties of human αB-Crystallin. Furthermore, the mutant protein indicated an attenuated in vitro chaperone activity. The molecular dynamics (MD) simulation confirmed the experimental results and indicated that p.R107L mutation could alter the proper conformation of human αB-Crystallin dimers. In summary, our results indicated that the p.R107L mutation could promote the formation of larger oligomers, diminish the stability and chaperone activity of human αB-Crystallin, and these changes, in turn, can play a crucial role in the development of cataract disorder.
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Affiliation(s)
- Farid Nasiri
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Parisa Ebrahimi
- Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | | | - Anis Barati
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Issa Zarei
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, 1416634793, Iran
| | - Jun Hong
- School of Life Sciences, Henan University, Kaifeng, 475000, People's Republic of China
| | - Masaru Hoshino
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | | | - Reza Yousefi
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran.
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3
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Darvazi M, Ghorbani M, Ramazi S, Allahverdi A, Abdolmaleki P. A computational study of the R120G mutation in human αB-crystallin: implications for structural stability and functionality. J Biomol Struct Dyn 2024; 42:5788-5798. [PMID: 37354135 DOI: 10.1080/07391102.2023.2229434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 06/17/2023] [Indexed: 06/26/2023]
Abstract
The eye is a vital organ in the visual system, which is composed of transparent vascular tissue. αB-crystallin, a significant protein found in the lens, plays a crucial role in our understanding of lens diseases. Mutations in the αB-crystallin protein can cause lens diseases, such as cataracts and myopathy. However, the molecular mechanism underlying the R120G mutation is not fully understood. In this study, we utilized molecular dynamics simulations to illustrate, in atomic detail, how the R120G mutation leads to the aggregation of αB-crystallin and scattering of light in the lens. Our findings show that the R120G mutation alters the dynamic and structural properties of the αB-crystallin protein. Specifically, this mutation causes the angle of the hairpin at the C-terminal to increase from 80° to 150°, while reducing the distance between the hydrophobic patches around residues 10 and 44-55 from 1.5 nm to 1 nm. In addition, our results showed that the mutation could disrupt the IPI motif - β4/β8 interaction. The disruption of this interaction could affect the αB-crystallin oligomerization and the chaperone activity of αB-crystallin protein. The exposed hydrophobic area at the IPI motif - β4/β8 could become the primary site for interprotein interactions, which are responsible for large-scale aggregation. We have demonstrated that, in wild-type αB-crystallin protein, salt bridges R120 and D109, R107 and D80 are formed. However, in the case of the R120G mutation, the salt bridges R120 and R109 are disrupted, and a new salt bridge with a different pattern is formed. In our study, it has been found that all of the changes associated with the R120G mutation are located at the interface of chains A and B, which could impact the multimerization of the αB-crystallin. Previous research on the K92-E99 residue has shown that a salt bridge in the dimer I can reduce the chaperone activity of the protein. Furthermore, the salt bridges R120 and D109, as well as R107 and D80 in dimer II, induce changes in the hydrophobic envelope of β-sheets in the α-crystallin domain (ACD). These changes could have an impact on the multimerization of the αB-crystallin, leading to disruption of the oligomer structure and aggregation. Moreover, the changes in the αB-crystallin resulting from the R120G mutation can lead to faulty interactions with other proteins, which can cause the aggregation of αB-crystallin with other proteins, such as desmin. These findings may provide new insights into the development of treatments for lens diseases.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Mona Darvazi
- Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Shahin Ramazi
- Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Abdollah Allahverdi
- Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Parviz Abdolmaleki
- Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
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4
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Miller AP, O'Neill SE, Lampi KJ, Reichow SL. The α-crystallin Chaperones Undergo a Quasi-ordered Co-aggregation Process in Response to Saturating Client Interaction. J Mol Biol 2024; 436:168499. [PMID: 38401625 PMCID: PMC11001518 DOI: 10.1016/j.jmb.2024.168499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 02/15/2024] [Accepted: 02/16/2024] [Indexed: 02/26/2024]
Abstract
Small heat shock proteins (sHSPs) are ATP-independent chaperones vital to cellular proteostasis, preventing protein aggregation events linked to various human diseases including cataract. The α-crystallins, αA-crystallin (αAc) and αB-crystallin (αBc), represent archetypal sHSPs that exhibit complex polydispersed oligomeric assemblies and rapid subunit exchange dynamics. Yet, our understanding of how this plasticity contributes to chaperone function remains poorly understood. Using biochemical and biophysical analyses combined with single-particle electron microscopy (EM), we examined structural changes in αAc, αBc and native heteromeric lens α-crystallins (αLc) in their apo-states and at varying degree of chaperone saturation leading to co-aggregation, using lysozyme and insulin as model clients. Quantitative single-particle analysis unveiled a continuous spectrum of oligomeric states formed during the co-aggregation process, marked by significant client-triggered expansion and quasi-ordered elongation of the sHSP oligomeric scaffold, whereby the native cage-like sHSP assembly displays a directional growth to accommodate saturating conditions of client sequestration. These structural modifications culminated in an apparent amorphous collapse of chaperone-client complexes, resulting in the creation of co-aggregates capable of scattering visible light. Intriguingly, these co-aggregates maintain internal morphological features of highly elongated sHSP oligomers with striking resemblance to polymeric α-crystallin species isolated from aged lens tissue. This mechanism appears consistent across αAc, αBc and αLc, albeit with varying degrees of susceptibility to client-induced co-aggregation. Importantly, our findings suggest that client-induced co-aggregation follows a distinctive mechanistic and quasi-ordered trajectory, distinct from a purely amorphous process. These insights reshape our understanding of the physiological and pathophysiological co-aggregation processes of α-crystallins, carrying potential implications for a pathway toward cataract formation.
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Affiliation(s)
- Adam P Miller
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA; Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA; Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Susan E O'Neill
- Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Kirsten J Lampi
- Biomaterial and Biomedical Sciences, Oregon Health & Science University, Portland, OR 97239, USA
| | - Steve L Reichow
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA; Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA; Department of Chemistry, Portland State University, Portland, OR 97201, USA.
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5
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Muranova LK, Vostrikova VM, Shatov VM, Sluchanko NN, Gusev NB. Interaction of the C-terminal immunoglobulin-like domains (Ig 22-24) of filamin C with human small heat shock proteins. Biochimie 2024; 219:146-154. [PMID: 38016530 DOI: 10.1016/j.biochi.2023.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/18/2023] [Accepted: 11/22/2023] [Indexed: 11/30/2023]
Abstract
Small heat shock proteins are the well-known regulators of the cytoskeleton integrity, yet their complexes with actin-binding proteins are underexplored. Filamin C, a dimeric 560 kDa protein, abundant in cardiac and skeletal muscles, crosslinks actin filaments and contributes to Z-disc formation and membrane-cytoskeleton attachment. Here, we analyzed the interaction of a human filamin C fragment containing immunoglobulin-like domains 22-24 (FLNC22-24) with five small heat shock proteins (HspB1, HspB5, HspB6, HspB7, HspB8) and their α-crystallin domains. On size-exclusion chromatography, only HspB7 or its α-crystallin domain formed complexes with FLNC22-24. Despite similar isoelectric points of the small heat shock proteins analyzed, only HspB7 and its α-crystallin domain interacted with FLNC22-24 on native gel electrophoresis. Crosslinking with glutaraldehyde confirmed the formation of complexes between HspB7 (or its α-crystallin domain) and the filamin С fragment, inhibiting intersubunit FLNC crosslinking. These data are consistent with the structure modeling using Alphafold. Thus, the C-terminal fragment (immunoglobulin-like domains 22-24) of filamin C contains the site for HspB7 (or its α-crystallin domain) interaction, which competes with FLNC22-24 dimerization and its probable interaction with different target proteins.
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Affiliation(s)
- Lydia K Muranova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119234, Russia
| | - Varvara M Vostrikova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119234, Russia
| | - Vladislav M Shatov
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119234, Russia
| | - Nikolai N Sluchanko
- A.N. Bach Institute of Biochemistry, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences, Moscow 119071, Russia
| | - Nikolai B Gusev
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119234, Russia.
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6
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Somee LR, Barati A, Shahsavani MB, Hoshino M, Hong J, Kumar A, Moosavi-Movahedi AA, Amanlou M, Yousefi R. Understanding the structural and functional changes and biochemical pathomechanism of the cardiomyopathy-associated p.R123W mutation in human αB-crystallin. Biochim Biophys Acta Gen Subj 2024; 1868:130579. [PMID: 38307443 DOI: 10.1016/j.bbagen.2024.130579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/04/2024]
Abstract
αB-crystallin, a member of the small heat shock protein (sHSP) family, is expressed in diverse tissues, including the eyes, brain, muscles, and heart. This protein plays a crucial role in maintaining eye lens transparency and exhibits holdase chaperone and anti-apoptotic activities. Therefore, structural and functional changes caused by genetic mutations in this protein may contribute to the development of disorders like cataract and cardiomyopathy. Recently, the substitution of arginine 123 with tryptophan (p.R123W mutation) in human αB-crystallin has been reported to trigger cardiomyopathy. In this study, human αB-crystallin was expressed in Escherichia coli (E. coli), and the missense mutation p.R123W was created using site-directed mutagenesis. Following purification via anion exchange chromatography, the structural and functional properties of both proteins were investigated and compared using a wide range of spectroscopic and microscopic methods. The p.R123W mutation induced significant alterations in the secondary, tertiary, and quaternary structures of human αB-crystallin. This pathogenic mutation resulted in an increased β-sheet structure and formation of protein oligomers with larger sizes compared to the wild-type protein. The mutant protein also exhibited reduced chaperone activity and lower thermal stability. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) demonstrated that the p.R123W mutant protein is more prone to forming amyloid aggregates. The structural and functional changes observed in the p.R123W mutant protein, along with its increased propensity for aggregation, could impact its proper functional interaction with the target proteins in the cardiac muscle, such as calcineurin. Our results provide an explanation for the pathogenic intervention of p.R123W mutant protein in the occurrence of hypertrophic cardiomyopathy (HCM).
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Affiliation(s)
- Leila Rezaei Somee
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Anis Barati
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | | | - Masaru Hoshino
- Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Jun Hong
- School of Life Sciences, Henan University, Kaifen, People's Republic of China
| | - Ashutosh Kumar
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India
| | | | - Massoud Amanlou
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Reza Yousefi
- Protein Chemistry Laboratory (PCL), Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran.
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7
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McFarland R, Reichow S. Dynamic fibrillar assembly of αB-crystallin induced by perturbation of the conserved NT-IXI motif resolved by cryo-EM. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.22.586355. [PMID: 38585788 PMCID: PMC10996541 DOI: 10.1101/2024.03.22.586355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
αB-crystallin is an archetypical member of the small heat-shock proteins (sHSPs) vital for cellular proteostasis and mitigating protein misfolding diseases. Gaining insights into the principles defining their molecular organization and chaperone function have been hindered by intrinsic dynamic properties and limited high-resolution structural analysis. To disentangle the mechanistic underpinnings of these dynamical properties, we mutated a conserved IXI-motif located within the N-terminal (NT) domain of human αB-crystallin. This resulted in a profound structural transformation, from highly polydispersed caged-like native assemblies into a comparatively well-ordered helical fibril state amenable to high-resolution cryo-EM analysis. The reversible nature of the induced fibrils facilitated interrogation of functional effects due to perturbation of the NT-IXI motif in both the native-like oligomer and fibril states. Together, our investigations unveiled several features thought to be key mechanistic attributes to sHSPs and point to a critical significance of the NT-IXI motif in αB-crystallin assembly, dynamics and chaperone activity.
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Affiliation(s)
- Russell McFarland
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, USA
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
- Current: Department of Biochemistry & Molecular Genetics, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Steve Reichow
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, USA
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
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8
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Zhao Z, Brooks D, Guo Y, Geisbrecht ER. Identification of CryAB as a target of NUAK kinase activity in Drosophila muscle tissue. Genetics 2023; 225:iyad167. [PMID: 37713608 PMCID: PMC10627272 DOI: 10.1093/genetics/iyad167] [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: 06/28/2023] [Revised: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 09/17/2023] Open
Abstract
Phosphorylation reactions performed by protein kinases are one of the most studied post-translational modifications within cells. Much is understood about conserved residues within protein kinase domains that perform catalysis of the phosphotransfer reaction, yet the identity of the target substrates and downstream biological effects vary widely among cells, tissues, and organisms. Here, we characterize key residues essential for NUAK kinase activity in Drosophila melanogaster myogenesis and homeostasis. Creation of a NUAK kinase-dead mutation using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 results in lethality at the embryo to larval transition, while loss of NUAK catalytic function later in development produces aggregation of the chaperone protein αB-crystallin/CryAB in muscle tissue. Yeast 2-hybrid assays demonstrate a physical interaction between NUAK and CryAB. We further show that a phospho-mimetic version of NUAK promotes the phosphorylation of CryAB and this post-translational modification occurs at 2 previously unidentified phosphosites that are conserved in the primary sequence of human CryAB. Mutation of these serine residues in D. melanogaster NUAK abolishes CryAB phosphorylation, thus, proving their necessity at the biochemical level. These studies together highlight the importance of kinase activity regulation and provide a platform to further explore muscle tissue proteostasis.
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Affiliation(s)
- Ziwei Zhao
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 1711 Claflin Rd, Manhattan, KS 66506, USA
| | - David Brooks
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 1711 Claflin Rd, Manhattan, KS 66506, USA
| | - Yungui Guo
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 1711 Claflin Rd, Manhattan, KS 66506, USA
| | - Erika R Geisbrecht
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 1711 Claflin Rd, Manhattan, KS 66506, USA
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9
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Miller AP, O'Neill SE, Lampi KJ, Reichow SL. The α-crystallin chaperones undergo a quasi-ordered co-aggregation process in response to saturating client interaction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.15.553435. [PMID: 37645910 PMCID: PMC10462102 DOI: 10.1101/2023.08.15.553435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Small heat shock proteins (sHSPs) are ATP-independent chaperones vital to cellular proteostasis, preventing protein aggregation events linked to various human diseases including cataract. The α-crystallins, αA-crystallin (αAc) and αB-crystallin (αBc), represent archetypal sHSPs that exhibit complex polydispersed oligomeric assemblies and rapid subunit exchange dynamics. Yet, our understanding of how this plasticity contributes to chaperone function remains poorly understood. This study investigates structural changes in αAc and αBc during client sequestration under varying degree of chaperone saturation. Using biochemical and biophysical analyses combined with single-particle electron microscopy (EM), we examined αAc and αBc in their apo-states and at various stages of client-induced co-aggregation, using lysozyme as a model client. Quantitative single-particle analysis unveiled a continuous spectrum of oligomeric states formed during the co-aggregation process, marked by significant client-triggered expansion and quasi-ordered elongation of the sHSP scaffold. These structural modifications culminated in an apparent amorphous collapse of chaperone-client complexes, resulting in the creation of co-aggregates capable of scattering visible light. Intriguingly, these co-aggregates maintain internal morphological features of highly elongated sHSP scaffolding with striking resemblance to polymeric α-crystallin species isolated from aged lens tissue. This mechanism appears consistent across both αAc and αBc, albeit with varying degrees of susceptibility to client-induced co-aggregation. Importantly, our findings suggest that client-induced co-aggregation follows a distinctive mechanistic and quasi-ordered trajectory, distinct from a purely amorphous process. These insights reshape our understanding of the physiological and pathophysiological co-aggregation processes of sHSPs, carrying potential implications for a pathway toward cataract formation.
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Affiliation(s)
- Adam P Miller
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, USA
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | - Susan E O'Neill
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | - Kirsten J Lampi
- Integrative Biosciences, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Steve L Reichow
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, USA
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, USA
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
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10
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Sun B, Kekenes-Huskey PM. Myofilament-associated proteins with intrinsic disorder (MAPIDs) and their resolution by computational modeling. Q Rev Biophys 2023; 56:e2. [PMID: 36628457 PMCID: PMC11070111 DOI: 10.1017/s003358352300001x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The cardiac sarcomere is a cellular structure in the heart that enables muscle cells to contract. Dozens of proteins belong to the cardiac sarcomere, which work in tandem to generate force and adapt to demands on cardiac output. Intriguingly, the majority of these proteins have significant intrinsic disorder that contributes to their functions, yet the biophysics of these intrinsically disordered regions (IDRs) have been characterized in limited detail. In this review, we first enumerate these myofilament-associated proteins with intrinsic disorder (MAPIDs) and recent biophysical studies to characterize their IDRs. We secondly summarize the biophysics governing IDR properties and the state-of-the-art in computational tools toward MAPID identification and characterization of their conformation ensembles. We conclude with an overview of future computational approaches toward broadening the understanding of intrinsic disorder in the cardiac sarcomere.
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Affiliation(s)
- Bin Sun
- Research Center for Pharmacoinformatics (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China), Department of Medicinal Chemistry and Natural Medicine Chemistry, College of Pharmacy, Harbin Medical University, Harbin 150081, China
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11
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The Aging Heart: A Molecular and Clinical Challenge. Int J Mol Sci 2022; 23:ijms232416033. [PMID: 36555671 PMCID: PMC9783309 DOI: 10.3390/ijms232416033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/05/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
Aging is associated with an increasing burden of morbidity, especially for cardiovascular diseases (CVDs). General cardiovascular risk factors, ischemic heart diseases, heart failure, arrhythmias, and cardiomyopathies present a significant prevalence in older people, and are characterized by peculiar clinical manifestations that have distinct features compared with the same conditions in a younger population. Remarkably, the aging heart phenotype in both healthy individuals and patients with CVD reflects modifications at the cellular level. An improvement in the knowledge of the physiological and pathological molecular mechanisms underlying cardiac aging could improve clinical management of older patients and offer new therapeutic targets.
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12
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Effects of Molecular Crowding and Betaine on HSPB5 Interactions, with Target Proteins Differing in the Quaternary Structure and Aggregation Mechanism. Int J Mol Sci 2022; 23:ijms232315392. [PMID: 36499725 PMCID: PMC9737104 DOI: 10.3390/ijms232315392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022] Open
Abstract
The aggregation of intracellular proteins may be enhanced under stress. The expression of heat-shock proteins (HSPs) and the accumulation of osmolytes are among the cellular protective mechanisms in these conditions. In addition, one should remember that the cell environment is highly crowded. The antiaggregation activity of HSPB5 and the effect on it of either a crowding agent (polyethylene glycol (PEG)) or an osmolyte (betaine), or their mixture, were tested on the aggregation of two target proteins that differ in the order of aggregation with respect to the protein: thermal aggregation of glutamate dehydrogenase and DTT-induced aggregation of lysozyme. The kinetic analysis of the dynamic light-scattering data indicates that crowding can decrease the chaperone-like activity of HSPB5. Nonetheless, the analytical ultracentrifugation shows the protective effect of HSPB5, which retains protein aggregates in a soluble state. Overall, various additives may either improve or impair the antiaggregation activity of HSPB5 against different protein targets. The mixed crowding arising from the presence of PEG and 1 M betaine demonstrates an extraordinary effect on the oligomeric state of protein aggregates. The shift in the equilibrium of HSPB5 dynamic ensembles allows for the regulation of its antiaggregation activity. Crowding can modulate HSPB5 activity by affecting protein-protein interactions.
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13
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Strauch A, Rossa B, Köhler F, Haeussler S, Mühlhofer M, Rührnößl F, Körösy C, Bushman Y, Conradt B, Haslbeck M, Weinkauf S, Buchner J. The permanently chaperone-active small heat shock protein Hsp17 from Caenorhabditis elegans exhibits topological separation of its N-terminal regions. J Biol Chem 2022; 299:102753. [PMID: 36442512 PMCID: PMC9800568 DOI: 10.1016/j.jbc.2022.102753] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 11/27/2022] Open
Abstract
Small Heat shock proteins (sHsps) are a family of molecular chaperones that bind nonnative proteins in an ATP-independent manner. Caenorhabditis elegans encodes 16 different sHsps, among them Hsp17, which is evolutionarily distinct from other sHsps in the nematode. The structure and mechanism of Hsp17 and how these may differ from other sHsps remain unclear. Here, we find that Hsp17 has a distinct expression pattern, structural organization, and chaperone function. Consistent with its presence under nonstress conditions, and in contrast to many other sHsps, we determined that Hsp17 is a mono-disperse, permanently active chaperone in vitro, which interacts with hundreds of different C. elegans proteins under physiological conditions. Additionally, our cryo-EM structure of Hsp17 reveals that in the 24-mer complex, 12 N-terminal regions are involved in its chaperone function. These flexible regions are located on the outside of the spherical oligomer, whereas the other 12 N-terminal regions are engaged in stabilizing interactions in its interior. This allows the same region in Hsp17 to perform different functions depending on the topological context. Taken together, our results reveal structural and functional features that further define the structural basis of permanently active sHsps.
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Affiliation(s)
- Annika Strauch
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Benjamin Rossa
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Fabian Köhler
- Faculty of Biology, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Simon Haeussler
- Faculty of Biology, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Moritz Mühlhofer
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Florian Rührnößl
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Caroline Körösy
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany; Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, Netherlands
| | - Yevheniia Bushman
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Barbara Conradt
- Faculty of Biology, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Martin Haslbeck
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Sevil Weinkauf
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany
| | - Johannes Buchner
- Center for Protein Assemblies and Department of Chemistry, Technische Universität München, Garching, Germany.
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14
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Li H, Yu Y, Ruan M, Jiao F, Chen H, Gao J, Weng Y, Bao Y. The mechanism for thermal-enhanced chaperone-like activity of α-crystallin against UV irradiation-induced aggregation of γD-crystallin. Biophys J 2022; 121:2233-2250. [PMID: 35619565 DOI: 10.1016/j.bpj.2022.05.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/11/2022] [Accepted: 05/20/2022] [Indexed: 11/18/2022] Open
Abstract
Exposure to solar UV irradiation damages γ-crystallin, leading to cataract formation via aggregation. α-Crystallin, as a small heat-shock protein (sHsps), efficiently suppresses this irreversible aggregation by selectively binding the denatured γ-crystallin monomer. In this study, liquid chromatography tandem mass spectrometry (LC-MS) was used to evaluate UV-325 nm irradiation-induced photodamage of human γD-crystallin in the presence of bovine α-crystallin, atomic force microscope (AFM) and dynamic light scattering (DLS) techniques were used to detect the quaternary structure changes of α-crystallin oligomer, and Fourier transform infrared (FTIR) spectroscopy and temperature-jump (T-jump) nanosecond time-resolved IR absorbance difference spectroscopy were used to probe the secondary structure changes of bovine α-crystallin. We find that the thermal-induced subunit dissociation of α-crystallin oligomer involves the breaking of hydrogen bonds at the dimeric interface, leading to three different spectral components at varied temperature regions as resolved from temperature-dependent IR spectra. Under UV-325 nm irradiation, unfolded γD-crystallin binds to the dissociated α-crystallin subunit to form αγ-complex, then follows the reassociation of αγ-complex to the partially dissociated α-crystallin oligomer. This prevents the aggregation of denatured γD-crystallin. The formation of the γD-bound α-crystallin oligomer is further confirmed by AFM and DLS analysis, which reveals an obvious size expansion in the reassociated αγ-oligomers. In addition, UV-325 nm irradiation causes a peptide bond cleavage of γD-crystallin at Ala158 in presence of α-crystallin. Our results suggest a very effective protection mechanism for subunits dissociated from α-crystallin oligomers against UV irradiation-induced aggregation of γD-crystallin, at an expense of a loss of a short C-terminal peptide in γD-crystallin.
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Affiliation(s)
- Hao Li
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; College of Chemical Biology and Biotechnology, Beijing University Shenzhen Graduate School, Shenzhen, China; Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yingying Yu
- Department of Ophthalmology, Peking University People's Hospital, Eye Diseases and Optometry Institute, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, College of Optometry, Peking University Health Science Center, Beijing, China
| | - Meixia Ruan
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Fang Jiao
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Hailong Chen
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jiali Gao
- College of Chemical Biology and Biotechnology, Beijing University Shenzhen Graduate School, Shenzhen, China; Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, China
| | - Yuxiang Weng
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Yongzhen Bao
- Department of Ophthalmology, Peking University People's Hospital, Eye Diseases and Optometry Institute, Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, College of Optometry, Peking University Health Science Center, Beijing, China.
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15
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Malik A, Khan JM, Alhomida AS, Ola MS. Modulation of the Structure and Stability of Novel Camel Lens Alpha-Crystallin by pH and Thermal Stress. Gels 2022; 8:gels8050273. [PMID: 35621572 PMCID: PMC9140948 DOI: 10.3390/gels8050273] [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: 03/14/2022] [Revised: 04/10/2022] [Accepted: 04/22/2022] [Indexed: 02/06/2023] Open
Abstract
Alpha-crystallin protein performs structural and chaperone functions in the lens and comprises alphaA and alphaB subunits at a molar ratio of 3:1. The highly complex alpha-crystallin structure challenges structural biologists because of its large dynamic quaternary structure (300−1000 kDa). Camel lens alpha-crystallin is a poorly characterized molecular chaperone, and the alphaB subunit possesses a novel extension at the N-terminal domain. We purified camel lens alpha-crystallin using size exclusion chromatography, and the purity was analyzed by gradient (4−12%) sodium dodecyl sulfate−polyacrylamide gel electrophoresis. Alpha-crystallin was equilibrated in the pH range of 1.0 to 7.5. Subsequently, thermal stress (20−94 °C) was applied to the alpha-crystallin samples, and changes in the conformation and stability were recorded by dynamic multimode spectroscopy and intrinsic and extrinsic fluorescence spectroscopic methods. Camel lens alpha-crystallin formed a random coil-like structure without losing its native-like beta-sheeted structure under two conditions: >50 °C at pH 7.5 and all temperatures at pH 2.0. The calculated enthalpy of denaturation, as determined by dynamic multimode spectroscopy at pH 7.5, 4.0, 2.0, and 1.0 revealed that alpha-crystallin never completely denatures under acidic conditions or thermal denaturation. Alpha-crystallin undergoes a single, reversible thermal transition at pH 7.5. The thermodynamic data (unfolding enthalpy and heat capacity change) and chaperone activities indicated that alpha-crystallin does not completely unfold above the thermal transition. Camels adapted to live in hot desert climates naturally exhibit the abovementioned unique features.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
- Correspondence:
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Abdullah S. Alhomida
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
| | - Mohammad Shamsul Ola
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; (A.S.A.); (M.S.O.)
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16
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Alpha B-Crystallin in Muscle Disease Prevention: The Role of Physical Activity. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27031147. [PMID: 35164412 PMCID: PMC8840510 DOI: 10.3390/molecules27031147] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/29/2022] [Accepted: 02/01/2022] [Indexed: 12/19/2022]
Abstract
HSPB5 or alpha B-crystallin (CRYAB), originally identified as lens protein, is one of the most widespread and represented of the human small heat shock proteins (sHSPs). It is greatly expressed in tissue with high rates of oxidative metabolism, such as skeletal and cardiac muscles, where HSPB5 dysfunction is associated with a plethora of human diseases. Since HSPB5 has a major role in protecting muscle tissues from the alterations of protein stability (i.e., microfilaments, microtubules, and intermediate filament components), it is not surprising that this sHSP is specifically modulated by exercise. Considering the robust content and the protective function of HSPB5 in striated muscle tissues, as well as its specific response to muscle contraction, it is then realistic to predict a specific role for exercise-induced modulation of HSPB5 in the prevention of muscle diseases caused by protein misfolding. After offering an overview of the current knowledge on HSPB5 structure and function in muscle, this review aims to introduce the reader to the capacity that different exercise modalities have to induce and/or activate HSPB5 to levels sufficient to confer protection, with the potential to prevent or delay skeletal and cardiac muscle disorders.
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17
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Mühlhofer M, Peters C, Kriehuber T, Kreuzeder M, Kazman P, Rodina N, Reif B, Haslbeck M, Weinkauf S, Buchner J. Phosphorylation activates the yeast small heat shock protein Hsp26 by weakening domain contacts in the oligomer ensemble. Nat Commun 2021; 12:6697. [PMID: 34795272 PMCID: PMC8602628 DOI: 10.1038/s41467-021-27036-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 11/01/2021] [Indexed: 11/18/2022] Open
Abstract
Hsp26 is a small heat shock protein (sHsp) from S. cerevisiae. Its chaperone activity is activated by oligomer dissociation at heat shock temperatures. Hsp26 contains 9 phosphorylation sites in different structural elements. Our analysis of phospho-mimetic mutations shows that phosphorylation activates Hsp26 at permissive temperatures. The cryo-EM structure of the Hsp26 40mer revealed contacts between the conserved core domain of Hsp26 and the so-called thermosensor domain in the N-terminal part of the protein, which are targeted by phosphorylation. Furthermore, several phosphorylation sites in the C-terminal extension, which link subunits within the oligomer, are sensitive to the introduction of negative charges. In all cases, the intrinsic inhibition of chaperone activity is relieved and the N-terminal domain becomes accessible for substrate protein binding. The weakening of domain interactions within and between subunits by phosphorylation to activate the chaperone activity in response to proteotoxic stresses independent of heat stress could be a general regulation principle of sHsps.
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Affiliation(s)
- Moritz Mühlhofer
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany
| | - Carsten Peters
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany
| | - Thomas Kriehuber
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany ,grid.420061.10000 0001 2171 7500Present Address: Boehringer Ingelheim, Birkendorfer Str. 65, 88397 Biberach an der Riß, Germany
| | - Marina Kreuzeder
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany ,grid.5252.00000 0004 1936 973XPresent Address: Ludwig-Maximilians-Universität München, Biozentrum Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany
| | - Pamina Kazman
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany ,grid.424277.0Present Address: Roche Diagnostics, Nonnenwald 2, 82377 Penzberg, Germany
| | - Natalia Rodina
- grid.6936.a0000000123222966BNMRZ, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 2, 85747 Garching, Germany ,Helmholtz-Zentrum München (HMGU), Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Bernd Reif
- grid.6936.a0000000123222966BNMRZ, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 2, 85747 Garching, Germany ,Helmholtz-Zentrum München (HMGU), Deutsches Forschungszentrum für Gesundheit und Umwelt, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Martin Haslbeck
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany
| | - Sevil Weinkauf
- grid.6936.a0000000123222966Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747 Garching, Germany
| | - Johannes Buchner
- Center for Protein Assemblies, Department of Chemistry, Technische Universität München, Ernst-Otto-Fischer Str. 8, 85747, Garching, Germany.
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18
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Fürsch J, Voormann C, Kammer KM, Stengel F. Structural Probing of Hsp26 Activation and Client Binding by Quantitative Cross-Linking Mass Spectrometry. Anal Chem 2021; 93:13226-13234. [PMID: 34542282 DOI: 10.1021/acs.analchem.1c02282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Small heat-shock proteins (sHSPs) are important members of the cellular stress response in all species. Their best-described function is the binding of early unfolding states and the resulting prevention of protein aggregation. Many sHSPs exist as a polydisperse composition of oligomers, which undergoes changes in subunit composition, folding status, and relative distribution upon heat activation. To date, only an incomplete picture of the mechanism of sHSP activation exists; in particular, the molecular basis of how sHSPs bind client proteins and mediate client specificity is not fully understood. In this study, we have applied cross-linking mass spectrometry (XL-MS) to obtain detailed structural information on sHSP activation and client binding for yeast Hsp26. Our cross-linking data reveals the middle domain of Hsp26 as a client-independent interface in multiple Hsp26::client complexes and indicates that client specificity is likely mediated via additional binding sites within its α-crystallin domain and C-terminal extension. Our quantitative XL-MS data underpins the middle domain as the main driver of heat-induced activation and client binding but shows that global rearrangements spanning all domains of Hsp26 take place simultaneously. We also investigated a Hsp26::client complex in the presence of Ssa1 (Hsp70) and Ydj1(Hsp40) at the initial stage of refolding and observe that the interaction between refolding chaperones is altered by the presence of a client protein, pointing to a mechanism where the interaction of Ydj1 with the HSP::client complex initiates the assembly of the active refolding machinery.
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Affiliation(s)
- Julius Fürsch
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Carsten Voormann
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
| | - Kai-Michael Kammer
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Florian Stengel
- Department of Biology, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
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19
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Park JC, Lee JS. Genome-wide identification of heat shock proteins in harpacticoid, cyclopoid, and calanoid copepods: Potential application in marine ecotoxicology. MARINE POLLUTION BULLETIN 2021; 169:112545. [PMID: 34111604 DOI: 10.1016/j.marpolbul.2021.112545] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 06/12/2023]
Abstract
Constant evolution of omics-technologies has provided access to identification of various important gene families. Recently, genome assemblies on widely used ecotoxicological model species, including rotifers and copepods have been completed and representative detoxification-related gene families have been discovered for biomarker genes. However, despite ubiquitous presence of stress-response proteins, limited information on full genome-wide report on heat shock proteins (Hsps) is available. Various studies have demonstrated multiple cellular functions of Hsps in living organisms as an important biomarker in response to abiotic and biotic stressors, however, full genome-wide identification of Hsps, particularly in aquatic invertebrates, has not been reported. This is the first study to report the entire Hsps and basal gene expression levels in three regional-specific copepods: Tigriopus japonicus and kingsejongensis, Paracyclopina nana, and Eurytemora affnis, and how each Hsp family gene is regulated at a basal level.
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Affiliation(s)
- Jun Chul Park
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jae-Seong Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
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20
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Sprague-Piercy MA, Rocha MA, Kwok AO, Martin RW. α-Crystallins in the Vertebrate Eye Lens: Complex Oligomers and Molecular Chaperones. Annu Rev Phys Chem 2021; 72:143-163. [PMID: 33321054 PMCID: PMC8062273 DOI: 10.1146/annurev-physchem-090419-121428] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
α-Crystallins are small heat-shock proteins that act as holdase chaperones. In humans, αA-crystallin is expressed only in the eye lens, while αB-crystallin is found in many tissues. α-Crystallins have a central domain flanked by flexible extensions and form dynamic, heterogeneous oligomers. Structural models show that both the C- and N-terminal extensions are important for controlling oligomerization through domain swapping. α-Crystallin prevents aggregation of damaged β- and γ-crystallins by binding to the client protein using a variety of binding modes. α-Crystallin chaperone activity can be compromised by mutation or posttranslational modifications, leading to protein aggregation and cataract. Because of their high solubility and their ability to form large, functional oligomers, α-crystallins are particularly amenable to structure determination by solid-state nuclear magnetic resonance (NMR) and solution NMR, as well as cryo-electron microscopy.
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Affiliation(s)
- Marc A Sprague-Piercy
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, USA;
| | - Megan A Rocha
- Department of Chemistry, University of California, Irvine, California 92697, USA
| | - Ashley O Kwok
- Department of Chemistry, University of California, Irvine, California 92697, USA
| | - Rachel W Martin
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, USA;
- Department of Chemistry, University of California, Irvine, California 92697, USA
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21
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Sadeh M, Rahat D, Meiner V, Fellig Y, Arad M, Schueler-Furman O, Hu Y, Li Y, Bönnemann CG, Lossos A. Multi-system neurological disorder associated with a CRYAB variant. Neurogenetics 2021; 22:117-125. [PMID: 33811585 DOI: 10.1007/s10048-021-00640-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/18/2021] [Indexed: 10/21/2022]
Abstract
We report a multiplex family with extended multisystem neurological phenotype associated with a CRYAB variant. Two affected siblings were evaluated with whole exome sequencing, muscle biopsy, laser microdissection, and mass spectrometry-based proteomic analysis. Both patients and their mother manifested a combination of early-onset cataracts, cardiomyopathy, cerebellar ataxia, optic atrophy, cognitive impairment, and myopathy. Whole exome sequencing identified a heterozygous c.458C>T variant mapped to the C-terminal extension domain of the Alpha-crystallin B chain, disrupting its function as a molecular chaperone and its ability to suppress protein aggregation. In accordance with the molecular findings, muscle biopsies revealed subsarcolemmal deposits that appeared dark with H&E and trichrome staining were negative for the other routine histochemical staining and for amyloid with the Congo-red stain. Electron microscopy demonstrated that the deposits were composed of numerous parallel fibrils. Laser microdissection and mass spectrometry-based proteomic analysis revealed that the inclusions are almost exclusively composed of crystallized chaperones/heat shock proteins. Moreover, a structural model suggests that Ser153 could be involved in monomer stabilization, dimer association, and possible binding of partner proteins. We propose that our report potentially expands the complex phenotypic spectrum of alpha B-crystallinopathies with possible effect of a CRYAB variant on the central nervous system.
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Affiliation(s)
- Menachem Sadeh
- Department of Neurology, Wolfson Medical Center and Tel Aviv University, Holon, Israel.
| | - Dolev Rahat
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, Institute for Biomedical Research Israel-Canada, Hebrew University, Jerusalem, Israel
| | - Vardiella Meiner
- Department of Genetics, Hadassah Medical Organization and Faculty of Medicine, Hebrew University, Jerusalem, Israel
| | - Yakov Fellig
- Department of Pathology, Genetics, Hadassah Medical Organization and Faculty of Medicine, Hebrew University, Jerusalem, Israel
| | - Michael Arad
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer and Tel Aviv University, Tel Aviv, Israel
| | - Ora Schueler-Furman
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, Institute for Biomedical Research Israel-Canada, Hebrew University, Jerusalem, Israel
| | - Ying Hu
- National Institute of Neurological Disorders and Stroke, Neurogenetics Branch, Bethesda, MD, USA
| | - Yan Li
- National Institute of Neurological Disorders and Stroke, Proteomics Core Facility, Bethesda, MD, USA
| | - Carsten G Bönnemann
- National Institute of Neurological Disorders and Stroke, Neurogenetics Branch, Bethesda, MD, USA
| | - Alexander Lossos
- Department of Neurology, Genetics, Hadassah Medical Organization and Faculty of Medicine, Hebrew University, Jerusalem, Israel
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22
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Bari KJ. The structural biology of crystallin aggregation: challenges and outlook. FEBS J 2021; 288:5888-5902. [DOI: 10.1111/febs.15684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/11/2020] [Accepted: 12/21/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Khandekar Jishan Bari
- Center for Interdisciplinary Sciences Tata Institute of Fundamental Research Hyderabad India
- Department of Chemical Sciences Indian Institute of Science Education and Research Berhampur India
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23
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Caporossi D, Parisi A, Fantini C, Grazioli E, Cerulli C, Dimauro I. AlphaB-crystallin and breast cancer: role and possible therapeutic strategies. Cell Stress Chaperones 2021; 26:19-28. [PMID: 33111264 PMCID: PMC7736448 DOI: 10.1007/s12192-020-01175-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/10/2020] [Accepted: 10/20/2020] [Indexed: 01/18/2023] Open
Abstract
AlphaB-crystallin (HSPB5) is one of the most prominent and well-studied members of the small heat shock protein (sHsp) family. To date, it is known that this protein modulates significant cellular processes and therefore, it is not surprising that its deregulation is involved in various human pathologies, including cancer diseases. Despite the pathogenic significance of HSPB5 in cancer and its regulatory mechanism related to aggressiveness is poorly understood, several reports describe the association of breast carcinoma progression with HSPB5, whose expression is also considered an independent predictor of breast cancer metastasis to the brain. Indeed, numerous authors indicate HSPB5 as a new valuable biomarker for clinicopathological parameters and poor prognosis in breast cancer. Considering the cytoprotective, anti-apoptotic, pro-angiogenic, and pro-metastatic properties of the sHsps, it is not surprising that they are considered as promising targets for anticancer treatment, even though, at present, a deeper understanding of their mode of action is needed to allow the development of precise therapeutic interventions. Data on the direct inhibition of different sHsps demonstrate promising results in cancer pathologies; however, specific strategies against HSPB5 have not been considered. This review highlights the most relevant findings on HSPB5 and its role in breast cancer, as well as the possible strategies in using HSPB5 inhibition for therapeutic purposes.
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Affiliation(s)
- Daniela Caporossi
- Unit of Biology and Genetics of Movement, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy
| | - Attilio Parisi
- Unit of Sport Medicine, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy
| | - Cristina Fantini
- Unit of Biology and Genetics of Movement, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy
| | - Elisa Grazioli
- Unit of Sport Medicine, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy
| | - Claudia Cerulli
- Unit of Sport Medicine, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy
| | - Ivan Dimauro
- Unit of Biology and Genetics of Movement, Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy.
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Roosen-Runge F, Gulotta A, Bucciarelli S, Casal-Dujat L, Garting T, Skar-Gislinge N, Obiols-Rabasa M, Farago B, Zaccarelli E, Schurtenberger P, Stradner A. Crowding in the Eye Lens: Modeling the Multisubunit Protein β-Crystallin with a Colloidal Approach. Biophys J 2020; 119:2483-2496. [PMID: 33189682 PMCID: PMC7822730 DOI: 10.1016/j.bpj.2020.10.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 10/07/2020] [Accepted: 10/19/2020] [Indexed: 11/29/2022] Open
Abstract
We present a multiscale characterization of aqueous solutions of the bovine eye lens protein βH crystallin from dilute conditions up to dynamical arrest, combining dynamic light scattering, small-angle x-ray scattering, tracer-based microrheology, and neutron spin echo spectroscopy. We obtain a comprehensive explanation of the observed experimental signatures from a model of polydisperse hard spheres with additional weak attraction. In particular, the model predictions quantitatively describe the multiscale dynamical results from microscopic nanometer cage diffusion over mesoscopic micrometer gradient diffusion up to macroscopic viscosity. Based on a comparative discussion with results from other crystallin proteins, we suggest an interesting common pathway for dynamical arrest in all crystallin proteins, with potential implications for the understanding of crowding effects in the eye lens.
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Affiliation(s)
| | | | | | | | - Tommy Garting
- Division of Physical Chemistry, Lund University, Lund, Sweden
| | | | | | | | - Emanuela Zaccarelli
- Institute for Complex Systems, National Research Council, Uos Sapienza, Rome, Italy; Department of Physics, Sapienza Università di Roma, Rome, Italy
| | | | - Anna Stradner
- Division of Physical Chemistry, Lund University, Lund, Sweden.
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25
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Malik A, Almaharfi HA, Khan JM, Hisamuddin M, Alamery SF, Haq SH, Ahmed MZ. Protection of ζ-crystallin by α-crystallin under thermal stress. Int J Biol Macromol 2020; 167:289-298. [PMID: 33278428 DOI: 10.1016/j.ijbiomac.2020.11.183] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/25/2020] [Accepted: 11/26/2020] [Indexed: 12/12/2022]
Abstract
Cataract is one of the major causes of blindness worldwide. Several factors including post-translational modification, thermal and solar radiations promote cataractogenesis. The camel lens proteins survive very harsh desert conditions and resist cataractogenesis. The folding and aggregation mechanism of camel lens proteins are poorly characterized. The camel lens contains three ubiquitous crystallins (α-, β-, and γ-crystallin) and a novel protein (ζ-crystallin) in large amounts. In this study, a sequence similarity search of camel α-crystallin with that of other organisms showed that the camel αB-crystallin consists of an extended N-terminal domain. Our results indicate that camel α-crystallin efficiently prevented aggregation of ζ-crystallin, with or without an obligate cofactor up to 89 °C. It performed a quick and efficient holdase function irrespective of the unfolding stage or aggregation. Camel α-crystallin exhibits approximately 20% chaperone activity between 30 and 40 °C and is completely activated above 40 °C. Camel α-crystallin underwent a single reversible thermal transition without loss of β-sheet secondary structure. Intrinsic tryptophan fluorescence and ANS binding experiments revealed two transitions which corresponded to activation of its chaperone function. In contrast to earlier studies, camel α-crystallin completely protected lens proteins during thermal stress.
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Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Hajar Ahmed Almaharfi
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia
| | - Malik Hisamuddin
- Center for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Salman Freeh Alamery
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Samina Hyder Haq
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Z Ahmed
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Saudi Arabia
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26
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Park JC, Kim DH, Lee Y, Lee MC, Kim TK, Yim JH, Lee JS. Genome-wide identification and structural analysis of heat shock protein gene families in the marine rotifer Brachionus spp.: Potential application in molecular ecotoxicology. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 36:100749. [PMID: 33065474 DOI: 10.1016/j.cbd.2020.100749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/26/2020] [Accepted: 09/26/2020] [Indexed: 01/07/2023]
Abstract
Heat shock proteins (Hsp) are class of conserved and ubiquitous stress proteins present in all living organisms from primitive to higher level. Various studies have demonstrated multiple cellular functions of Hsp in living organisms as an important biomarker in response to abiotic and biotic stressors including temperature, salinity, pH, hypoxia, environmental pollutants, and pathogens. However, full understanding on the mechanism and pathway involved in the induction of Hsp still remains challenging, especially in aquatic invertebrates. In this study, the entire Hsp family and subfamily members in the marine rotifers Brachionus spp., one of the cosmopolitan ecotoxicological model organisms, have been genome-widely identified. In Brachionus spp. Hsp family was comprised of Hsp10, small hsp (sHsp), Hsp40, Hsp60, Hsp70/105, and Hsp90, with highest number of genes found within Hsp40 DnaJ homolog subfamily C members. Also, the differences in the orientation of the conserved motifs within Hsp family may have induced differences in transcriptional gene modulation in response to thermal stress in Brachionus koreanus. Overall, Hsp family-specific domains were highly conserved in all three Brachionus spp., relative to Homo sapiens and across other animal taxa and these findings will be helpful for future ecotoxicological studies focusing on Hsps.
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Affiliation(s)
- Jun Chul Park
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Duck-Hyun Kim
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Yoseop Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Min-Chul Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Tai Kyoung Kim
- Division of Polar Life Science, Korea Polar Research Institute, Incheon 21990, South Korea
| | - Joung Han Yim
- Division of Polar Life Science, Korea Polar Research Institute, Incheon 21990, South Korea
| | - Jae-Seong Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
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27
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Grosas AB, Rekas A, Mata JP, Thorn DC, Carver JA. The Aggregation of αB-Crystallin under Crowding Conditions Is Prevented by αA-Crystallin: Implications for α-Crystallin Stability and Lens Transparency. J Mol Biol 2020; 432:5593-5613. [PMID: 32827531 DOI: 10.1016/j.jmb.2020.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 02/08/2023]
Abstract
One of the most crowded biological environments is the eye lens which contains a high concentration of crystallin proteins. The molecular chaperones αB-crystallin (αBc) with its lens partner αA-crystallin (αAc) prevent deleterious crystallin aggregation and cataract formation. However, some forms of cataract are associated with structural alteration and dysfunction of αBc. While many studies have investigated the structure and function of αBc under dilute in vitro conditions, the effect of crowding on these aspects is not well understood despite its in vivo relevance. The structure and chaperone ability of αBc under conditions that mimic the crowded lens environment were investigated using the polysaccharide Ficoll 400 and bovine γ-crystallin as crowding agents and a variety of biophysical methods, principally contrast variation small-angle neutron scattering. Under crowding conditions, αBc unfolds, increases its size/oligomeric state, decreases its thermal stability and chaperone ability, and forms kinetically distinct amorphous and fibrillar aggregates. However, the presence of αAc stabilizes αBc against aggregation. These observations provide a rationale, at the molecular level, for the aggregation of αBc in the crowded lens, a process that exhibits structural and functional similarities to the aggregation of cataract-associated αBc mutants R120G and D109A under dilute conditions. Strategies that maintain or restore αBc stability, as αAc does, may provide therapeutic avenues for the treatment of cataract.
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Affiliation(s)
- Aidan B Grosas
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
| | - Agata Rekas
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
| | - Jitendra P Mata
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
| | - David C Thorn
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Canberra, ACT, 2601, Australia.
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28
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Proteinaceous Transformers: Structural and Functional Variability of Human sHsps. Int J Mol Sci 2020; 21:ijms21155448. [PMID: 32751672 PMCID: PMC7432308 DOI: 10.3390/ijms21155448] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/27/2020] [Accepted: 07/29/2020] [Indexed: 02/04/2023] Open
Abstract
The proteostasis network allows organisms to support and regulate the life cycle of proteins. Especially regarding stress, molecular chaperones represent the main players within this network. Small heat shock proteins (sHsps) are a diverse family of ATP-independent molecular chaperones acting as the first line of defense in many stress situations. Thereby, the promiscuous interaction of sHsps with substrate proteins results in complexes from which the substrates can be refolded by ATP-dependent chaperones. Particularly in vertebrates, sHsps are linked to a broad variety of diseases and are needed to maintain the refractive index of the eye lens. A striking key characteristic of sHsps is their existence in ensembles of oligomers with varying numbers of subunits. The respective dynamics of these molecules allow the exchange of subunits and the formation of hetero-oligomers. Additionally, these dynamics are closely linked to the chaperone activity of sHsps. In current models a shift in the equilibrium of the sHsp ensemble allows regulation of the chaperone activity, whereby smaller oligomers are commonly the more active species. Different triggers reversibly change the oligomer equilibrium and regulate the activity of sHsps. However, a finite availability of high-resolution structures of sHsps still limits a detailed mechanistic understanding of their dynamics and the correlating recognition of substrate proteins. Here we summarize recent advances in understanding the structural and functional relationships of human sHsps with a focus on the eye-lens αA- and αB-crystallins.
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29
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Chebotareva NA, Roman SG, Borzova VA, Eronina TB, Mikhaylova VV, Kurganov BI. Chaperone-Like Activity of HSPB5: The Effects of Quaternary Structure Dynamics and Crowding. Int J Mol Sci 2020; 21:ijms21144940. [PMID: 32668633 PMCID: PMC7404038 DOI: 10.3390/ijms21144940] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/04/2020] [Accepted: 07/10/2020] [Indexed: 11/16/2022] Open
Abstract
Small heat-shock proteins (sHSPs) are ATP-independent molecular chaperones that interact with partially unfolded proteins, preventing their aberrant aggregation, thereby exhibiting a chaperone-like activity. Dynamics of the quaternary structure plays an important role in the chaperone-like activity of sHSPs. However, relationship between the dynamic structure of sHSPs and their chaperone-like activity remains insufficiently characterized. Many factors (temperature, ions, a target protein, crowding etc.) affect the structure and activity of sHSPs. The least studied is an effect of crowding on sHSPs activity. In this work the chaperone-like activity of HSPB5 was quantitatively characterized by dynamic light scattering using two test systems, namely test systems based on heat-induced aggregation of muscle glycogen phosphorylase b (Phb) at 48 °C and dithiothreitol-induced aggregation of α-lactalbumin at 37 °C. Analytical ultracentrifugation was used to control the oligomeric state of HSPB5 and target proteins. The possible anti-aggregation functioning of suboligomeric forms of HSPB5 is discussed. The effect of crowding on HSPB5 anti-aggregation activity was characterized using Phb as a target protein. The duration of the nucleation stage was shown to decrease with simultaneous increase in the relative rate of aggregation of Phb in the presence of HSPB5 under crowded conditions. Crowding may subtly modulate sHSPs activity.
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30
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Nava Ramírez T, Hansberg W. Características comunes de las chaperonas pequeñas y diméricas. TIP REVISTA ESPECIALIZADA EN CIENCIAS QUÍMICO-BIOLÓGICAS 2020. [DOI: 10.22201/fesz.23958723e.2020.0.234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Las chaperonas moleculares constituyen un mecanismo importante para evitar la muerte celular provocada por la agregación de proteínas. Las chaperonas independientes del ATP son un grupo de proteínas de bajo peso molecular que pueden proteger y ayudar a alcanzar la estructura nativa de las proteínas desplegadas o mal plegadas sin necesidad de un gasto energético. Hemos encontrado que el dominio C-terminal de las catalasas de subunidad grande tiene actividad de chaperona. Por ello, en esta revisión analizamos las características más comunes de las chaperonas pequeñas y más estudiadas como: αB-cristalina, Hsp20, Spy, Hsp33 y Hsp31. En particular, se examina la participación de los aminoácidos hidrofóbicos y de los aminoácidos con carga en el reconocimiento de las proteínas sustrato, así como el papel que tiene la forma dimérica y su oligomerización en la actividad de chaperona. En cada una de esas chaperonas revisaremos la estructura de la proteína, su función, localización celular e importancia para la célula.
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31
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Abstract
In vivo, small heat-shock proteins (sHsps) are key players in maintaining a healthy proteome. αB-crystallin (αB-c) or HspB5 is one of the most widespread and populous of the ten human sHsps. Intracellularly, αB-c acts via its molecular chaperone action as the first line of defence in preventing target protein unfolding and aggregation under conditions of cellular stress. In this review, we explore how the structure of αB-c confers its function and interactions within its oligomeric self, with other sHsps, and with aggregation-prone target proteins. Firstly, the interaction between the two highly conserved regions of αB-c, the central α-crystallin domain and the C-terminal IXI motif and how this regulates αB-c chaperone activity are explored. Secondly, subunit exchange is rationalised as an integral structural and functional feature of αB-c. Thirdly, it is argued that monomeric αB-c may be its most chaperone-species active, but at the cost of increased hydrophobicity and instability. Fourthly, the reasons why hetero-oligomerisation of αB-c with other sHsps is important in regulating cellular proteostasis are examined. Finally, the interaction of αB-c with aggregation-prone, partially folded target proteins is discussed. Overall, this paper highlights the remarkably diverse capabilities of αB-c as a caretaker of the cell.
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Affiliation(s)
- Junna Hayashi
- Research School of Chemistry, The Australian National University, Acton, ACT, 2601, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT, 2601, Australia.
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32
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Shatov VM, Strelkov SV, Gusev NB. The Heterooligomerization of Human Small Heat Shock Proteins Is Controlled by Conserved Motif Located in the N-Terminal Domain. Int J Mol Sci 2020; 21:ijms21124248. [PMID: 32549212 PMCID: PMC7352286 DOI: 10.3390/ijms21124248] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/07/2020] [Accepted: 06/12/2020] [Indexed: 01/18/2023] Open
Abstract
Ubiquitously expressed human small heat shock proteins (sHsps) HspB1, HspB5, HspB6 and HspB8 contain a conserved motif (S/G)RLFD in their N-terminal domain. For each of them, we prepared mutants with a replacement of the conserved R by A (R/A mutants) and a complete deletion of the pentapeptide (Δ mutants) and analyzed their heterooligomerization with other wild-type (WT) human sHsps. We found that WT HspB1 and HspB5 formed heterooligomers with HspB6 only upon heating. In contrast, both HspB1 mutants interacted with WT HspB6 even at low temperature. HspB1/HspB6 heterooligomers revealed a broad size distribution with equimolar ratio suggestive of heterodimers as building blocks, while HspB5/HspB6 heterooligomers had an approximate 2:1 ratio. In contrast, R/A or Δ mutants of HspB6, when mixed with either HspB1 or HspB5, resulted in heterooligomers with a highly variable molar ratio and a decreased HspB6 incorporation. No heterooligomerization of HspB8 or its mutants with either HspB1 or HspB5 could be detected. Finally, R/A or Δ mutations had no effect on heterooligomerization of HspB1 and HspB5 as analyzed by ion exchange chromatography. We conclude that the conserved N-terminal motif plays an important role in heterooligomer formation, as especially pronounced in HspB6 lacking the C-terminal IXI motif.
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Affiliation(s)
- Vladislav M. Shatov
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian;
| | - Sergei V. Strelkov
- Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium;
| | - Nikolai B. Gusev
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119991, Russian;
- Correspondence:
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33
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Muranova LK, Strelkov SV, Gusev NB. Effect of cataract-associated mutations in the N-terminal domain of αB-crystallin (HspB5). Exp Eye Res 2020; 197:108091. [PMID: 32533979 DOI: 10.1016/j.exer.2020.108091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 05/08/2020] [Accepted: 05/28/2020] [Indexed: 11/18/2022]
Abstract
Physico-chemical properties of three cataract-associated missense mutants of αB-crystallin (HspB5) (R11H, P20S, R56W) were analyzed. The oligomers formed by the R11H mutant were smaller, whereas the oligomers of the P20S and R56W mutants were larger than those of the wild-type protein. The P20S mutant possessed lower thermal stability than the wild-type HspB5 or two other HspB5 mutants. All HspB5 mutants were able to form heterooligomeric complexes with αA-crystallin (HspB4), a genuine component of eye lens. However, the P20S and R56W mutants were less effective in the formation of these complexes and properties of heterooligomeric complexes formed by these mutants and HspB4 and analyzed by ion-exchange chromatography were different from those formed by the wild-type HspB5 and HspB4. All HspB5 variants also heterooligomerized with another partner protein, HspB6. Specifically for the P20S mutant forming two distinct sizes of homooligomers, only the smaller homooligomer population was able to interact with HspB6. P20S and R56W mutants possessed lower chaperone-like activity than the wild-type HspB5 when UV-irradiated βL-crystallin was used as a model substrate. Importantly, all three mutations are localized in three earlier postulated short α-helical regions present in the N-terminal domain of αB-crystallin. These observations suggest an important structural and functional role of these regions. Correspondingly, therein localized mutations ultimately result in clinically relevant cataracts.
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Affiliation(s)
- Lydia K Muranova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, 119991, Russian Federation
| | - Sergei V Strelkov
- Laboratory of Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Nikolai B Gusev
- Department of Biochemistry, School of Biology, Moscow State University, Moscow, 119991, Russian Federation.
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34
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Roskamp KW, Paulson CN, Brubaker WD, Martin RW. Function and Aggregation in Structural Eye Lens Crystallins. Acc Chem Res 2020; 53:863-874. [PMID: 32271004 DOI: 10.1021/acs.accounts.0c00014] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Crystallins are transparent, refractive proteins that contribute to the focusing power of the vertebrate eye lens. These proteins are extremely soluble and resist aggregation for decades, even under crowded conditions. Crystallins have evolved to avoid strong interprotein interactions and have unusual hydration properties. Crystallin aggregation resulting from mutation, damage, or aging can lead to cataract, a disease state characterized by opacity of the lens.Different aggregation mechanisms can occur, following multiple pathways and leading to aggregates with varied morphologies. Studies of variant proteins found in individuals with childhood-onset cataract have provided insight into the molecular factors underlying crystallin stability and solubility. Modulation of exposed hydrophobic surface is critical, as is preventing specific intermolecular interactions that could provide nucleation sites for aggregation. Biophysical measurements and structural biology techniques are beginning to provide a detailed picture of how crystallins crowd into the lens, providing high refractivity while avoiding excessively tight binding that would lead to aggregation.Despite the central biological importance of refractivity, relatively few experimental measurements have been made for lens crystallins. Our work and that of others have shown that hydration is important to the high refractive index of crystallin proteins, as are interactions between pairs of aromatic residues and potentially other specific structural features.This Account describes our efforts to understand both the functional and disease states of vertebrate eye lens crystallins, particularly the γ-crystallins. We use a variety of biophysical techniques, notably NMR spectroscopy, to investigate crystallin stability and solubility. In the first section, we describe efforts to understand the relative stability and aggregation propensity of different γS-crystallin variants. The second section focuses on interactions of these proteins with the holdase chaperone αB-crystallin. The third, fourth, and fifth sections explore different modes of aggregation available to crystallin proteins, and the final section highlights the importance of refractive index and the sometimes conflicting demands of selection for refractivity and solubility.
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Affiliation(s)
- Kyle W. Roskamp
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Carolyn N. Paulson
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - William D. Brubaker
- SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025, United States
| | - Rachel W. Martin
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
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35
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Baughman HER, Pham THT, Adams CS, Nath A, Klevit RE. Release of a disordered domain enhances HspB1 chaperone activity toward tau. Proc Natl Acad Sci U S A 2020; 117:2923-2929. [PMID: 31974309 PMCID: PMC7022203 DOI: 10.1073/pnas.1915099117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Small heat shock proteins (sHSPs) are a class of ATP-independent molecular chaperones that play vital roles in maintaining protein solubility and preventing aberrant protein aggregation. They form highly dynamic, polydisperse oligomeric ensembles and contain long intrinsically disordered regions. Experimental challenges posed by these properties have greatly impeded our understanding of sHSP structure and mechanism of action. Here we characterize interactions between the human sHSP HspB1 (Hsp27) and microtubule-associated protein tau, which is implicated in multiple dementias, including Alzheimer's disease. We show that tau binds both to a well-known binding groove within the structured alpha-crystallin domain (ACD) and to sites within the enigmatic, disordered N-terminal region (NTR) of HspB1. However, only interactions involving the NTR lead to productive chaperone activity, whereas ACD binding is uncorrelated with chaperone function. The tau-binding groove in the ACD also binds short hydrophobic regions within HspB1 itself, and HspB1 mutations that disrupt these intrinsic ACD-NTR interactions greatly enhance chaperone activity toward tau. This leads to a mechanism in which the release of the disordered NTR from a binding groove on the ACD enhances chaperone activity toward tau. The study advances understanding of the mechanisms by which sHSPs achieve their chaperone activity against amyloid-forming clients and how cells defend against pathological tau aggregation. Furthermore, the resulting mechanistic model points to ways in which sHSP chaperone activity may be increased, either by native factors within the cell or by therapeutic intervention.
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Affiliation(s)
- Hannah E R Baughman
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Thanh-Hau T Pham
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Chloe S Adams
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195
| | - Abhinav Nath
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195
| | - Rachel E Klevit
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA 98195;
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36
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Nappi L, Aguda AH, Nakouzi NA, Lelj-Garolla B, Beraldi E, Lallous N, Thi M, Moore S, Fazli L, Battsogt D, Stief S, Ban F, Nguyen NT, Saxena N, Dueva E, Zhang F, Yamazaki T, Zoubeidi A, Cherkasov A, Brayer GD, Gleave M. Ivermectin inhibits HSP27 and potentiates efficacy of oncogene targeting in tumor models. J Clin Invest 2020; 130:699-714. [PMID: 31845908 PMCID: PMC6994194 DOI: 10.1172/jci130819] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 10/22/2019] [Indexed: 01/07/2023] Open
Abstract
HSP27 is highly expressed in, and supports oncogene addiction of, many cancers. HSP27 phosphorylation is a limiting step for activation of this protein and a target for inhibition, but its highly disordered structure challenges rational structure-guided drug discovery. We performed multistep biochemical, structural, and computational experiments to define a spherical 24-monomer complex composed of 12 HSP27 dimers with a phosphorylation pocket flanked by serine residues between their N-terminal domains. Ivermectin directly binds this pocket to inhibit MAPKAP2-mediated HSP27 phosphorylation and depolymerization, thereby blocking HSP27-regulated survival signaling and client-oncoprotein interactions. Ivermectin potentiated activity of anti-androgen receptor and anti-EGFR drugs in prostate and EGFR/HER2-driven tumor models, respectively, identifying a repurposing approach for cotargeting stress-adaptive responses to overcome resistance to inhibitors of oncogenic pathway signaling.
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Affiliation(s)
- Lucia Nappi
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | | | | | | | - Eliana Beraldi
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Nada Lallous
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Marisa Thi
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Susan Moore
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Ladan Fazli
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | | | - Sophie Stief
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Fuqiang Ban
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Nham T. Nguyen
- Department of Biochemistry and Molecular Biology, Life Sciences Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Neetu Saxena
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Evgenia Dueva
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Fan Zhang
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | | | - Amina Zoubeidi
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Artem Cherkasov
- Department of Urologic Sciences, Vancouver Prostate Centre, and
| | - Gary D. Brayer
- Department of Biochemistry and Molecular Biology, Life Sciences Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Martin Gleave
- Department of Urologic Sciences, Vancouver Prostate Centre, and
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37
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Kaiser CJO, Peters C, Schmid PWN, Stavropoulou M, Zou J, Dahiya V, Mymrikov EV, Rockel B, Asami S, Haslbeck M, Rappsilber J, Reif B, Zacharias M, Buchner J, Weinkauf S. The structure and oxidation of the eye lens chaperone αA-crystallin. Nat Struct Mol Biol 2019; 26:1141-1150. [PMID: 31792453 PMCID: PMC7115824 DOI: 10.1038/s41594-019-0332-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/10/2019] [Indexed: 11/08/2022]
Abstract
The small heat shock protein αA-crystallin is a molecular chaperone important for the optical properties of the vertebrate eye lens. It forms heterogeneous oligomeric ensembles. We determined the structures of human αA-crystallin oligomers by combining cryo-electron microscopy, cross-linking/mass spectrometry, NMR spectroscopy and molecular modeling. The different oligomers can be interconverted by the addition or subtraction of tetramers, leading to mainly 12-, 16- and 20-meric assemblies in which interactions between N-terminal regions are important. Cross-dimer domain-swapping of the C-terminal region is a determinant of αA-crystallin heterogeneity. Human αA-crystallin contains two cysteines, which can form an intramolecular disulfide in vivo. Oxidation in vitro requires conformational changes and oligomer dissociation. The oxidized oligomers, which are larger than reduced αA-crystallin and destabilized against unfolding, are active chaperones and can transfer the disulfide to destabilized substrate proteins. The insight into the structure and function of αA-crystallin provides a basis for understanding its role in the eye lens.
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Affiliation(s)
- Christoph J O Kaiser
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Carsten Peters
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Philipp W N Schmid
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Maria Stavropoulou
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Juan Zou
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Vinay Dahiya
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Evgeny V Mymrikov
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
- Institute for Biochemistry and Molecular Biology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Beate Rockel
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Sam Asami
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Martin Haslbeck
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
- Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Bernd Reif
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Martin Zacharias
- Center for Integrated Protein Science Munich at the Physics Department, Technische Universität München, Garching, Germany
| | - Johannes Buchner
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany.
| | - Sevil Weinkauf
- Center for Integrated Protein Science Munich at the Department Chemie, Technische Universität München, Garching, Germany.
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38
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Clouser AF, Baughman HER, Basanta B, Guttman M, Nath A, Klevit RE. Interplay of disordered and ordered regions of a human small heat shock protein yields an ensemble of 'quasi-ordered' states. eLife 2019; 8:e50259. [PMID: 31573509 PMCID: PMC6791718 DOI: 10.7554/elife.50259] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 09/30/2019] [Indexed: 12/14/2022] Open
Abstract
Small heat shock proteins (sHSPs) are nature's 'first responders' to cellular stress, interacting with affected proteins to prevent their aggregation. Little is known about sHSP structure beyond its structured α-crystallin domain (ACD), which is flanked by disordered regions. In the human sHSP HSPB1, the disordered N-terminal region (NTR) represents nearly 50% of the sequence. Here, we present a hybrid approach involving NMR, hydrogen-deuterium exchange mass spectrometry, and modeling to provide the first residue-level characterization of the NTR. The results support a model in which multiple grooves on the ACD interact with specific NTR regions, creating an ensemble of 'quasi-ordered' NTR states that can give rise to the known heterogeneity and plasticity of HSPB1. Phosphorylation-dependent interactions inform a mechanism by which HSPB1 is activated under stress conditions. Additionally, we examine the effects of disease-associated NTR mutations on HSPB1 structure and dynamics, leveraging our emerging structural insights.
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Affiliation(s)
- Amanda F Clouser
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
| | - Hannah ER Baughman
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
- Department of Medicinal ChemistryUniversity of WashingtonSeattleUnited States
| | - Benjamin Basanta
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
| | - Miklos Guttman
- Department of Medicinal ChemistryUniversity of WashingtonSeattleUnited States
| | - Abhinav Nath
- Department of Medicinal ChemistryUniversity of WashingtonSeattleUnited States
| | - Rachel E Klevit
- Department of BiochemistryUniversity of WashingtonSeattleUnited States
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39
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Janowska MK, Baughman HER, Woods CN, Klevit RE. Mechanisms of Small Heat Shock Proteins. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a034025. [PMID: 30833458 DOI: 10.1101/cshperspect.a034025] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Small heat shock proteins (sHSPs) are ATP-independent chaperones that delay formation of harmful protein aggregates. sHSPs' role in protein homeostasis has been appreciated for decades, but their mechanisms of action remain poorly understood. This gap in understanding is largely a consequence of sHSP properties that make them recalcitrant to detailed study. Multiple stress-associated conditions including pH acidosis, oxidation, and unusual availability of metal ions, as well as reversible stress-induced phosphorylation can modulate sHSP chaperone activity. Investigations of sHSPs reveal that sHSPs can engage in transient or long-lived interactions with client proteins depending on solution conditions and sHSP or client identity. Recent advances in the field highlight both the diversity of function within the sHSP family and the exquisite sensitivity of individual sHSPs to cellular and experimental conditions. Here, we will present and highlight current understanding, recent progress, and future challenges.
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Affiliation(s)
- Maria K Janowska
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Hannah E R Baughman
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Christopher N Woods
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Rachel E Klevit
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
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40
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Lyon YA, Collier MP, Riggs DL, Degiacomi MT, Benesch JLP, Julian RR. Structural and functional consequences of age-related isomerization in α-crystallins. J Biol Chem 2019; 294:7546-7555. [PMID: 30804217 PMCID: PMC6514633 DOI: 10.1074/jbc.ra118.007052] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/15/2019] [Indexed: 12/31/2022] Open
Abstract
Long-lived proteins are subject to spontaneous degradation and may accumulate a range of modifications over time, including subtle alterations such as side-chain isomerization. Recently, tandem MS has enabled identification and characterization of such peptide isomers, including those differing only in chirality. However, the structural and functional consequences of these perturbations remain largely unexplored. Here, we examined the impact of isomerization of aspartic acid or epimerization of serine at four sites mapping to crucial oligomeric interfaces in human αA- and αB-crystallin, the most abundant chaperone proteins in the eye lens. To characterize the effect of isomerization on quaternary assembly, we utilized synthetic peptide mimics, enzyme assays, molecular dynamics calculations, and native MS experiments. The oligomerization of recombinant forms of αA- and αB-crystallin that mimic isomerized residues deviated from native behavior in all cases. Isomerization also perturbs recognition of peptide substrates, either enhancing or inhibiting kinase activity. Specifically, epimerization of serine (αASer-162) dramatically weakened inter-subunit binding. Furthermore, phosphorylation of αBSer-59, known to play an important regulatory role in oligomerization, was severely inhibited by serine epimerization and altered by isomerization of nearby αBAsp-62. Similarly, isomerization of αBAsp-109 disrupted a vital salt bridge with αBArg-120, a contact that when broken has previously been shown to yield aberrant oligomerization and aggregation in several disease-associated variants. Our results illustrate how isomerization of amino acid residues, which may seem to be only a minor structural perturbation, can disrupt native structural interactions with profound consequences for protein assembly and activity.
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Affiliation(s)
- Yana A Lyon
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521
| | - Miranda P Collier
- the Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Dylan L Riggs
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521
| | - Matteo T Degiacomi
- the Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom
| | - Justin L P Benesch
- the Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom, and
| | - Ryan R Julian
- From the Department of Chemistry, University of California, Riverside, Riverside, California 92521,
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41
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Hori Y, Fujiwara H, Fujiwara W, Makabe K. Grafting a short chameleon sequence from αB crystallin into a β-sheet scaffold protein. Proteins 2019; 87:416-424. [PMID: 30684364 DOI: 10.1002/prot.25663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 01/17/2019] [Accepted: 01/22/2019] [Indexed: 11/08/2022]
Abstract
Many protein and peptide sequences are self-assembled into β-sheet-rich fibrous structures called amyloids. Their atomic details provide insights into fundamental knowledge related to amyloid diseases. To study the detailed structure of the amyloid, we have developed a model system that mimics the self-assembling process of the amyloid within a water-soluble protein, termed peptide self-assembly mimic (PSAM). PSAM enables capturing of a peptide sequence within a water-soluble protein, thus making structural and energetics-related studies possible. In this work, we extend our PSAM approach to a naturally occurring chameleon sequence from αB crystallin. We chose "Val-Leu-Gly-Asp-Val (VLGDV)", a five amino-acid sequence, which forms a β-turn in the native structure and a β-barrel in the amyloid oligomer cylindrin, as a grafting sequence to the PSAM scaffold. The crystal structure revealed that the sequence grafting induced β-sheet bending at the grafted site. We further investigated the role of the central glycine residue and found that its role in the β-sheet bending is dependent on the neighboring residues. The ability of PSAM to observe the structural alterations induced by the grafted sequence provides an opportunity to evaluate the structural impact of a sequence from the peptide self-assembly.
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Affiliation(s)
- Yuki Hori
- Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata, Japan
| | - Hideki Fujiwara
- Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata, Japan
| | - Wataru Fujiwara
- Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata, Japan
| | - Koki Makabe
- Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata, Japan
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42
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Dahiya V, Buchner J. Functional principles and regulation of molecular chaperones. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2018; 114:1-60. [PMID: 30635079 DOI: 10.1016/bs.apcsb.2018.10.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To be able to perform their biological function, a protein needs to be correctly folded into its three dimensional structure. The protein folding process is spontaneous and does not require the input of energy. However, in the crowded cellular environment where there is high risk of inter-molecular interactions that may lead to protein molecules sticking to each other, hence forming aggregates, protein folding is assisted. Cells have evolved robust machinery called molecular chaperones to deal with the protein folding problem and to maintain proteins in their functional state. Molecular chaperones promote efficient folding of newly synthesized proteins, prevent their aggregation and ensure protein homeostasis in cells. There are different classes of molecular chaperones functioning in a complex interplay. In this review, we discuss the principal characteristics of different classes of molecular chaperones, their structure-function relationships, their mode of regulation and their involvement in human disorders.
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Affiliation(s)
- Vinay Dahiya
- Center for Integrated Protein Science Munich CIPSM at the Department Chemie, Technische Universität München, Garching, Germany
| | - Johannes Buchner
- Center for Integrated Protein Science Munich CIPSM at the Department Chemie, Technische Universität München, Garching, Germany.
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43
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Haslbeck M, Weinkauf S, Buchner J. Small heat shock proteins: Simplicity meets complexity. J Biol Chem 2018; 294:2121-2132. [PMID: 30385502 DOI: 10.1074/jbc.rev118.002809] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Small heat shock proteins (sHsps) are a ubiquitous and ancient family of ATP-independent molecular chaperones. A key characteristic of sHsps is that they exist in ensembles of iso-energetic oligomeric species differing in size. This property arises from a unique mode of assembly involving several parts of the subunits in a flexible manner. Current evidence suggests that smaller oligomers are more active chaperones. Thus, a shift in the equilibrium of the sHsp ensemble allows regulating the chaperone activity. Different mechanisms have been identified that reversibly change the oligomer equilibrium. The promiscuous interaction with non-native proteins generates complexes that can form aggregate-like structures from which native proteins are restored by ATP-dependent chaperones such as Hsp70 family members. In recent years, this basic paradigm has been expanded, and new roles and new cofactors, as well as variations in structure and regulation of sHsps, have emerged.
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Affiliation(s)
- Martin Haslbeck
- From the Department of Chemie and Center for Integrated Protein Science, Technische Universität München, Lichtenbergstrasse 4, 85 748 Garching, Germany
| | - Sevil Weinkauf
- From the Department of Chemie and Center for Integrated Protein Science, Technische Universität München, Lichtenbergstrasse 4, 85 748 Garching, Germany
| | - Johannes Buchner
- From the Department of Chemie and Center for Integrated Protein Science, Technische Universität München, Lichtenbergstrasse 4, 85 748 Garching, Germany
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44
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Muranova LK, Sudnitsyna MV, Gusev NB. αB-Crystallin Phosphorylation: Advances and Problems. BIOCHEMISTRY (MOSCOW) 2018; 83:1196-1206. [DOI: 10.1134/s000629791810005x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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45
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Jovcevski B, Andrew Aquilina J, Benesch JLP, Ecroyd H. The influence of the N-terminal region proximal to the core domain on the assembly and chaperone activity of αB-crystallin. Cell Stress Chaperones 2018; 23:827-836. [PMID: 29520626 PMCID: PMC6111084 DOI: 10.1007/s12192-018-0889-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 02/19/2018] [Accepted: 02/24/2018] [Indexed: 01/24/2023] Open
Abstract
αB-Crystallin (HSPB5) is a small heat-shock protein that is composed of dimers that then assemble into a polydisperse ensemble of oligomers. Oligomerisation is mediated by heterologous interactions between the C-terminal tail of one dimer and the core "α-crystallin" domain of another and stabilised by interactions made by the N-terminal region. Comparatively little is known about the latter contribution, but previous studies have suggested that residues in the region 54-60 form contacts that stabilise the assembly. We have generated mutations in this region (P58A, S59A, S59K, R56S/S59R and an inversion of residues 54-60) to examine their impact on oligomerisation and chaperone activity in vitro. By using native mass spectrometry, we found that all the αB-crystallin mutants were assembly competent, populating similar oligomeric distributions to wild-type, ranging from 16-mers to 30-mers. However, circular dichroism spectroscopy, intrinsic tryptophan and bis-ANS fluorescence studies demonstrated that the secondary structure differs to wild type, the 54-60 inversion mutation having the greatest impact. All the mutants exhibited a dramatic decrease in exposed hydrophobicity. We also found that the mutants in general were equally active as the wild-type protein in inhibiting the amorphous aggregation of insulin and seeded amyloid fibrillation of α-synuclein in vitro, except for the 54-60 inversion mutant, which was significantly less effective at inhibiting insulin aggregation. Our data indicate that alterations in the part of the N-terminal region proximal to the core domain do not drastically affect the oligomerisation of αB-crystallin, reinforcing the robustness of αB-crystallin in functioning as a molecular chaperone.
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Affiliation(s)
- Blagojce Jovcevski
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Northfields Ave, Wollongong, NSW, 2522, Australia
| | - J Andrew Aquilina
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Northfields Ave, Wollongong, NSW, 2522, Australia
| | - Justin L P Benesch
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
| | - Heath Ecroyd
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Northfields Ave, Wollongong, NSW, 2522, Australia.
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46
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Liu Z, Wang C, Li Y, Zhao C, Li T, Li D, Zhang S, Liu C. Mechanistic insights into the switch of αB-crystallin chaperone activity and self-multimerization. J Biol Chem 2018; 293:14880-14890. [PMID: 30076220 DOI: 10.1074/jbc.ra118.004034] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/25/2018] [Indexed: 12/15/2022] Open
Abstract
αB-Crystallin (αBc) is a small heat shock protein that protects cells against abnormal protein aggregation and disease-related degeneration. αBc is also a major structural protein that forms polydisperse multimers that maintain the liquid-like property of the eye lens. However, the relationship and regulation of the two functions have yet to be explored. Here, by combining NMR spectroscopy and multiple biophysical approaches, we found that αBc uses a conserved β4/β8 surface of the central α-crystallin domain to bind α-synuclein and Tau proteins and prevent them from aggregating into pathological amyloids. We noted that this amyloid-binding surface can also bind the C-terminal IPI motif of αBc, which mediates αBc multimerization and weakens its chaperone activity. We further show that disruption of the IPI binding impairs αBc self-multimerization but enhances its chaperone activity. Our work discloses the structural mechanism underlying the regulation of αBc chaperone activity and self-multimerization and sheds light on the different functions of αBc in antagonizing neurodegeneration and maintaining eye lens liquidity.
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Affiliation(s)
- Zhenying Liu
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China.,University of the Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Chuchu Wang
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China.,University of the Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Yichen Li
- Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Bio-X Institutes, Shanghai Jiao Tong University, Shanghai 200030, China, and
| | - Chunyu Zhao
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China.,University of the Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Tongzhou Li
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China.,University of the Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Dan Li
- Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Bio-X Institutes, Shanghai Jiao Tong University, Shanghai 200030, China, and
| | - Shengnan Zhang
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China,
| | - Cong Liu
- From the Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 26 Qiuyue Road, Shanghai 201210, China,
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47
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Mishra S, Chandler SA, Williams D, Claxton DP, Koteiche HA, Stewart PL, Benesch JLP, Mchaourab HS. Engineering of a Polydisperse Small Heat-Shock Protein Reveals Conserved Motifs of Oligomer Plasticity. Structure 2018; 26:1116-1126.e4. [PMID: 29983375 DOI: 10.1016/j.str.2018.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/10/2018] [Accepted: 05/18/2018] [Indexed: 01/21/2023]
Abstract
Small heat-shock proteins (sHSPs) are molecular chaperones that bind partially and globally unfolded states of their client proteins. Previously, we discovered that the archaeal Hsp16.5, which forms ordered and symmetric 24-subunit oligomers, can be engineered to transition to an ordered and symmetric 48-subunit oligomer by insertion of a peptide from human HspB1 (Hsp27). Here, we uncovered the existence of an array of oligomeric states (30-38 subunits) that can be populated as a consequence of altering the sequence and length of the inserted peptide. Polydisperse Hsp16.5 oligomers displayed higher affinity to a model client protein consistent with a general mechanism for recognition and binding that involves increased access of the hydrophobic N-terminal region. Our findings, which integrate structural and functional analyses from evolutionarily distant sHSPs, support a model wherein the modular architecture of these proteins encodes motifs of oligomer polydispersity, dissociation, and expansion to achieve functional diversity and regulation.
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Affiliation(s)
- Sanjay Mishra
- Chemical & Physical Biology Program, Vanderbilt University, Nashville 37232, TN, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville 37232, TN, USA
| | - Shane A Chandler
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK
| | - Dewight Williams
- John M. Cowley Center for High Resolution Electron Microscopy, Arizona State University, Tempe 85287, AZ, USA
| | - Derek P Claxton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville 37232, TN, USA
| | - Hanane A Koteiche
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville 37232, TN, USA
| | - Phoebe L Stewart
- Department of Pharmacology Case Western Reserve University, Cleveland, OH 44106, USA
| | | | - Hassane S Mchaourab
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville 37232, TN, USA.
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48
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Dimauro I, Antonioni A, Mercatelli N, Caporossi D. The role of αB-crystallin in skeletal and cardiac muscle tissues. Cell Stress Chaperones 2018; 23:491-505. [PMID: 29190034 PMCID: PMC6045558 DOI: 10.1007/s12192-017-0866-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 11/23/2017] [Accepted: 11/25/2017] [Indexed: 12/25/2022] Open
Abstract
All organisms and cells respond to various stress conditions such as environmental, metabolic, or pathophysiological stress by generally upregulating, among others, the expression and/or activation of a group of proteins called heat shock proteins (HSPs). Among the HSPs, special attention has been devoted to the mutations affecting the function of the αB-crystallin (HSPB5), a small heat shock protein (sHsp) playing a critical role in the modulation of several cellular processes related to survival and stress recovery, such as protein degradation, cytoskeletal stabilization, and apoptosis. Because of the emerging role in general health and disease conditions, the main objective of this mini-review is to provide a brief account on the role of HSPB5 in mammalian muscle physiopathology. Here, we report the current known state of the regulation and localization of HSPB5 in skeletal and cardiac tissue, making also a critical summary of all human HSPB5 mutations known to be strictly associated to specific skeletal and cardiac diseases, such as desmin-related myopathies (DRM), dilated (DCM) and restrictive (RCM) cardiomyopathy. Finally, pointing to putative strategies for HSPB5-based therapy to prevent or counteract these forms of human muscular disorders.
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Affiliation(s)
- Ivan Dimauro
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Rome, Italy
| | - Ambra Antonioni
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Rome, Italy
| | - Neri Mercatelli
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Rome, Italy
| | - Daniela Caporossi
- Department of Movement, Human and Health Sciences, University of Rome “Foro Italico”, Rome, Italy
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49
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3D structure of the native α-crystallin from bovine eye lens. Int J Biol Macromol 2018; 117:1289-1298. [PMID: 29870813 DOI: 10.1016/j.ijbiomac.2018.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/01/2018] [Indexed: 12/30/2022]
Abstract
α-Crystallin is the major eye lens protein that has been shown to support lens transparency by preventing the aggregation of lens proteins. The 3D structure of α-crystallin is largely unknown. Electron microscopy, single-particle 3D reconstruction, size exclusion chromatography, dynamic light scattering, and analytical ultracentrifugation were used to study the structure of the native α-crystallin. Native α-crystallin has a wide distribution in size. The shape of mass distribution is temperature-dependent, but the oligomers with a sedimentation coefficient of ~22 S (750-830 kDa) strongly prevailed at all temperatures used. A 3D model of native α-crystallin with resolution of ~2 nm was created. The model is asymmetrical, has an elongated bean-like shape 13 × 19 nm with a dense core and filamentous "kernel". It does not contain a central cavity. The majority of α-crystallin particles regardless of experimental conditions are 13 × 19 nm, which corresponds to 22S sedimentation coefficient, hydrodynamic diameter 20 nm and mass of 750-830 kD. These particles are in dynamic equilibrium with particles of smaller and larger sizes.
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Rusin A, Seymour C, Mothersill C. Chronic fatigue and immune deficiency syndrome (CFIDS), cellular metabolism, and ionizing radiation: a review of contemporary scientific literature and suggested directions for future research. Int J Radiat Biol 2018; 94:212-228. [DOI: 10.1080/09553002.2018.1422871] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Andrej Rusin
- Department of Biology, McMaster University, Hamilton, Canada
| | - Colin Seymour
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada
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