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Webster JM, Darling AL, Uversky VN, Blair LJ. Small Heat Shock Proteins, Big Impact on Protein Aggregation in Neurodegenerative Disease. Front Pharmacol 2019; 10:1047. [PMID: 31619995 PMCID: PMC6759932 DOI: 10.3389/fphar.2019.01047] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 08/19/2019] [Indexed: 12/15/2022] Open
Abstract
Misfolding, aggregation, and aberrant accumulation of proteins are central components in the progression of neurodegenerative disease. Cellular molecular chaperone systems modulate proteostasis, and, therefore, are primed to influence aberrant protein-induced neurotoxicity and disease progression. Molecular chaperones have a wide range of functions from facilitating proper nascent folding and refolding to degradation or sequestration of misfolded substrates. In disease states, molecular chaperones can display protective or aberrant effects, including the promotion and stabilization of toxic protein aggregates. This seems to be dependent on the aggregating protein and discrete chaperone interaction. Small heat shock proteins (sHsps) are a class of molecular chaperones that typically associate early with misfolded proteins. These interactions hold proteins in a reversible state that helps facilitate refolding or degradation by other chaperones and co-factors. These sHsp interactions require dynamic oligomerization state changes in response to diverse cellular triggers and, unlike later steps in the chaperone cascade of events, are ATP-independent. Here, we review evidence for modulation of neurodegenerative disease-relevant protein aggregation by sHsps. This includes data supporting direct physical interactions and potential roles of sHsps in the stewardship of pathological protein aggregates in brain. A greater understanding of the mechanisms of sHsp chaperone activity may help in the development of novel therapeutic strategies to modulate the aggregation of pathological, amyloidogenic proteins. sHsps-targeting strategies including modulators of expression or post-translational modification of endogenous sHsps, small molecules targeted to sHsp domains, and delivery of engineered molecular chaperones, are also discussed.
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Affiliation(s)
- Jack M Webster
- Department of Molecular Medicine, USF Byrd Institute, University of South Florida, Tampa, FL, United States
| | - April L Darling
- Department of Molecular Medicine, USF Byrd Institute, University of South Florida, Tampa, FL, United States
| | - Vladimir N Uversky
- Department of Molecular Medicine, USF Byrd Institute, University of South Florida, Tampa, FL, United States
| | - Laura J Blair
- Department of Molecular Medicine, USF Byrd Institute, University of South Florida, Tampa, FL, United States
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Fujiwara H, Hongo K, Hori Y, Yoshida N, Makabe K. β-sheet elasticity of peptide self-assembly mimic, PSAM, with a grafted sequence characterized by comprehensive analyses of isomorphous crystals. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Benson DR, Lovell S, Mehzabeen N, Galeva N, Cooper A, Gao P, Battaile KP, Zhu H. Crystal structures of the naturally fused CS and cytochrome b 5 reductase (b 5R) domains of Ncb5or reveal an expanded CS fold, extensive CS-b 5R interactions and productive binding of the NAD(P) + nicotinamide ring. Acta Crystallogr D Struct Biol 2019; 75:628-638. [PMID: 31282472 PMCID: PMC6718094 DOI: 10.1107/s205979831900754x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/23/2019] [Indexed: 01/19/2023] Open
Abstract
Ncb5or (NADH-cytochrome b5 oxidoreductase), a cytosolic ferric reductase implicated in diabetes and neurological diseases, comprises three distinct domains, cytochrome b5 (b5) and cytochrome b5 reductase (b5R) domains separated by a CHORD-Sgt1 (CS) domain, and a novel 50-residue N-terminal region. Understanding how interdomain interactions in Ncb5or facilitate the shuttling of electrons from NAD(P)H to heme, and how the process compares with the microsomal b5 (Cyb5A) and b5R (Cyb5R3) system, is of interest. A high-resolution structure of the b5 domain (PDB entry 3lf5) has previously been reported, which exhibits substantial differences in comparison to Cyb5A. The structural characterization of a construct comprising the naturally fused CS and b5R domains with bound FAD and NAD+ (PDB entry 6mv1) or NADP+ (PDB entry 6mv2) is now reported. The structures reveal that the linker between the CS and b5R cores is more ordered than predicted, with much of it extending the β-sandwich motif of the CS domain. This limits the flexibility between the two domains, which recognize one another via a short β-sheet motif and a network of conserved side-chain hydrogen bonds, salt bridges and cation-π interactions. Notable differences in FAD-protein interactions in Ncb5or and Cyb5R3 provide insight into the selectivity for docking of their respective b5 redox partners. The structures also afford a structural explanation for the unusual ability of Ncb5or to utilize both NADH and NADPH, and represent the first examples of native, fully oxidized b5R family members in which the nicotinamide ring of NAD(P)+ resides in the active site. Finally, the structures, together with sequence alignments, show that the b5R domain is more closely related to single-domain Cyb5R proteins from plants, fungi and some protists than to Cyb5R3 from animals.
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Affiliation(s)
- David R. Benson
- Department of Chemistry, The University of Kansas, 1567 Irving Hill Road, Lawrence, KS 66045, USA
| | - Scott Lovell
- Protein Structure Laboratory, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Nurjahan Mehzabeen
- Protein Structure Laboratory, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Nadezhda Galeva
- Analytical Proteomics Laboratory, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Anne Cooper
- Protein Production Group, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Philip Gao
- Protein Production Group, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Kevin P. Battaile
- IMCA-CAT, APS, Argonne National Laboratory, 9700 South Cass Avenue, Building 435A, Argonne, IL 60439, USA
| | - Hao Zhu
- Department of Clinical Laboratory Sciences, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
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Wright MA, Ruggeri FS, Saar KL, Challa PK, Benesch JLP, Knowles TPJ. Analysis of αB-crystallin polydispersity in solution through native microfluidic electrophoresis. Analyst 2019; 144:4413-4424. [PMID: 31215547 DOI: 10.1039/c9an00382g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In recent years, significant advancements have been made in the understanding of the population distributions and dynamic oligomeric states of the molecular chaperone αB-crystallin and its core domain variants. In this work, we provide solution-phase evidence of the polydispersity of αB-crystallin using microfluidic methods, used for separating the oligomeric species present in solution according to their different electrophoretic mobilities on-chip in a matter of seconds. We in particular demonstrate that microfluidic high-field electrophoresis and diffusion can detect the oligomerisation of these highly dynamic molecular chaperones and characterise the dominant oligomeric species present. We thereby provide a robust microfluidic method for characterising the individual species within complex protein mixtures of biological relevance.
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Affiliation(s)
- Maya A Wright
- Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, UK. and Fluidic Analytics Ltd., Unit 5 Chesterton Mill, French's Road CB4 3NP, UK
| | | | - Kadi L Saar
- Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, UK.
| | - Pavan K Challa
- Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, UK.
| | - Justin L P Benesch
- Department of Physical and Theoretical Chemistry, University of Oxford, UK
| | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, UK. and Department of Physics, University of Cambridge, JJ Thomson Ave, Cambridge CB3 0HE, UK
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Charcot-Marie-Tooth 2F (Hsp27 mutations): A review. Neurobiol Dis 2019; 130:104505. [PMID: 31212070 DOI: 10.1016/j.nbd.2019.104505] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/13/2022] Open
Abstract
Charcot-Marie-Tooth disease is a commonly inherited form of neuropathy. Although named over 100 years ago, identification of subtypes of Charcot-Marie-Tooth has rapidly expanded in the preceding decades with the advancement of genetic sequencing, including type 2F (CMT2F), due to mutations in heat shock protein 27 (Hsp27). However, despite CMT being one of the most common inherited neurological diseases, definitive mechanistic models of pathology and effective treatments for CMT2F are lacking. This review extensively profiles the published literature on CMT2F and distal hereditary motor neuropathy II (dHMN II), a similar neuropathy with exclusively motor symptoms that is also due to mutations in Hsp27. This includes a review of case reports and sequencing studies detailing disease course. Included are tables listing of all known published mutations of Hsp27 that cause symptoms of CMT2F and dHMN II. Furthermore, pathological mechanisms are assessed. While many groups have established pathologies relating to defective chaperone function, cellular neurofilament and microtubule structure and function, and mitochondrial and metabolic dysfunction, there are still discrepancies in results between different model systems. Moreover, initial mouse models have also produced promising results with similar phenotypes to humans, however discrepancies still exist. Both patient-focused and scientific studies have demonstrated variability in phenotypes even considering specific mutations. Given the clinical heterogeneity in presentation, CMT2F and dHMN II likely result from similar pathological mechanisms of the same general disease process that may present distinctly due to other genetic and environment influences. Determining how these influences exert their effects to produce pathology contributing to the disease phenotype will be a major future challenge ahead in the field.
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Failure of Oxysterols Such as Lanosterol to Restore Lens Clarity from Cataracts. Sci Rep 2019; 9:8459. [PMID: 31186457 PMCID: PMC6560215 DOI: 10.1038/s41598-019-44676-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 05/01/2019] [Indexed: 01/13/2023] Open
Abstract
The paradigm that cataracts are irreversible and that vision from cataracts can only be restored through surgery has recently been challenged by reports that oxysterols such as lanosterol and 25-hydroxycholesterol can restore vision by binding to αB-crystallin chaperone protein to dissolve or disaggregate lenticular opacities. To confirm this premise, in vitro rat lens studies along with human lens protein solubilization studies were conducted. Cataracts were induced in viable rat lenses cultured for 48 hours in TC-199 bicarbonate media through physical trauma, 10 mM ouabain as Na+/K+ ATPase ion transport inhibitor, or 1 mM of an experimental compound that induces water influx into the lens. Subsequent 48-hour incubation with 15 mM of lanosterol liposomes failed to either reverse these lens opacities or prevent the further progression of cataracts to the nuclear stage. Similarly, 3-day incubation of 47-year old human lenses in media containing 0.20 mM lanosterol or 60-year-old human lenses in 0.25 and 0.50 mM 25-hydroxycholesterol failed to increase the levels of soluble lens proteins or decrease the levels of insoluble lens proteins. These binding studies were followed up with in silico binding studies of lanosterol, 25-hydroxycholesterol, and ATP as a control to two wild type (2WJ7 and 2KLR) and one R120G mutant (2Y1Z) αB-crystallins using standard MOETM (Molecular Operating Environment) and Schrödinger's Maestro software. Results confirmed that compared to ATP, both oxysterols failed to reach the acceptable threshold binding scores for good predictive binding to the αB-crystallins. In summary, all three studies failed to provide evidence that lanosterol or 25-hydroxycholesterol have either anti-cataractogenic activity or bind aggregated lens protein to dissolve cataracts.
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Identification and Expression Analysis of Four Small Heat Shock Protein Genes in Cigarette Beetle, Lasioderma serricorne (Fabricius). INSECTS 2019; 10:insects10050139. [PMID: 31096618 PMCID: PMC6572347 DOI: 10.3390/insects10050139] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/08/2019] [Accepted: 05/12/2019] [Indexed: 11/17/2022]
Abstract
Small heat shock proteins (sHsps) are molecular chaperones that play crucial roles in the stress adaption of insects. In this study, we identified and characterized four sHsp genes (LsHsp19.4, 20.2, 20.3, and 22.2) from the cigarette beetle, Lasioderma serricorne (Fabricius). The four cDNAs encoded proteins of 169, 180, 181, and 194 amino acids with molecular weights of 19.4, 20.2, 20.3, and 22.2 kDa, respectively. The four LsHsp sequences possessed a typical sHsp domain structure. Quantitative real-time PCR analyses revealed that LsHsp19.4 and 20.3 transcripts were most abundant in pupae, whereas the transcript levels of LsHsp20.2 and 22.2 were highest in adults. Transcripts of three LsHsp genes were highly expressed in the larval fat body, whereas LsHsp20.2 displayed an extremely high expression level in the gut. Expression of the four LsHsp genes was dramatically upregulated in larvae exposed to 20-hydroxyecdysone. The majority of the LsHsp genes were significantly upregulated in response to heat and cold treatments, while LsHsp19.4 was insensitive to cold stress. The four genes were upregulated when challenged by immune triggers (peptidoglycan isolated from Staphylococcus aureus and from Escherichia coli 0111:B4). Exposure to CO2 increased LsHsp20.2 and 20.3 transcript levels, but the LsHsp19.4 transcript level declined. The results suggest that different LsHsp genes play important and distinct regulatory roles in L. serricorne development and in response to diverse stresses.
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58
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Collier MP, Alderson TR, de Villiers CP, Nicholls D, Gastall HY, Allison TM, Degiacomi MT, Jiang H, Mlynek G, Fürst DO, van der Ven PFM, Djinovic-Carugo K, Baldwin AJ, Watkins H, Gehmlich K, Benesch JLP. HspB1 phosphorylation regulates its intramolecular dynamics and mechanosensitive molecular chaperone interaction with filamin C. SCIENCE ADVANCES 2019; 5:eaav8421. [PMID: 31131323 PMCID: PMC6530996 DOI: 10.1126/sciadv.aav8421] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 04/16/2019] [Indexed: 05/13/2023]
Abstract
Mechanical force-induced conformational changes in proteins underpin a variety of physiological functions, typified in muscle contractile machinery. Mutations in the actin-binding protein filamin C (FLNC) are linked to musculoskeletal pathologies characterized by altered biomechanical properties and sometimes aggregates. HspB1, an abundant molecular chaperone, is prevalent in striated muscle where it is phosphorylated in response to cues including mechanical stress. We report the interaction and up-regulation of both proteins in three mouse models of biomechanical stress, with HspB1 being phosphorylated and FLNC being localized to load-bearing sites. We show how phosphorylation leads to increased exposure of the residues surrounding the HspB1 phosphosite, facilitating their binding to a compact multidomain region of FLNC proposed to have mechanosensing functions. Steered unfolding of FLNC reveals that its extension trajectory is modulated by the phosphorylated region of HspB1. This may represent a posttranslationally regulated chaperone-client protection mechanism targeting over-extension during mechanical stress.
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Affiliation(s)
- Miranda P. Collier
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - T. Reid Alderson
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - Carin P. de Villiers
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Headington, Oxford OX3 9DU, UK
| | - Daisy Nicholls
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - Heidi Y. Gastall
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - Timothy M. Allison
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
- Biomolecular Interaction Centre and School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8140, New Zealand
| | - Matteo T. Degiacomi
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, UK
| | - He Jiang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Headington, Oxford OX3 9DU, UK
| | - Georg Mlynek
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Dieter O. Fürst
- Department of Molecular Cell Biology, Institute for Cell Biology, University of Bonn, D53121 Bonn, Germany
| | - Peter F. M. van der Ven
- Department of Molecular Cell Biology, Institute for Cell Biology, University of Bonn, D53121 Bonn, Germany
| | - Kristina Djinovic-Carugo
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Andrew J. Baldwin
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Headington, Oxford OX3 9DU, UK
| | - Katja Gehmlich
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Headington, Oxford OX3 9DU, UK
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
- Corresponding author. (J.L.P.B.); (K.G.)
| | - Justin L. P. Benesch
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK
- Corresponding author. (J.L.P.B.); (K.G.)
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Melgar-Asensio I, Kandela I, Aird F, Darjatmoko SR, de Los Rios C, Sorenson CM, Albert DM, Sheibani N, Henkin J. Extended Intravitreal Rabbit Eye Residence of Nanoparticles Conjugated With Cationic Arginine Peptides for Intraocular Drug Delivery: In Vivo Imaging. Invest Ophthalmol Vis Sci 2019; 59:4071-4081. [PMID: 30098194 PMCID: PMC6088811 DOI: 10.1167/iovs.18-24087] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Purpose Drug delivery by intravitreal injection remains problematic, small agents and macromolecules both clearing rapidly. Typical carriers use microparticles (>2 μm), with size-related liabilities, to slow diffusion. We recently described cationic nanoparticles (NP) where conjugated Arg peptides prolonged residence in rat eyes, through ionic interaction with vitreal poly-anions. Here we extended this strategy to in vivo tracking of NP-conjugate (NPC) clearance from rabbit eyes. Relating t1/2 to zeta potential, and varied dose, we estimated the limits of this charge-based delivery system. Methods NPC carried covalently attached PEG8-2Arg or PEG8-3Arg pentapeptides, having known sequences from human eye proteins. Peptides were conjugated (61–64 per NPC); each NP/NPC also carried a cyanine7 tag (<0.5 dye/particle). In vivo imaging system (IVIS), after intravitreal injection, estimated NPC loss by 800-nm photon emission (745-nm excitation) at 1 to 3-week intervals following initial scan at day 10. Results NPC of 2Arg-peptides or 3Arg-peptides showed clearance t1/2 of 7 days and 17 days respectively, unconjugated NP t1/2 was <<5 days. Doses of 90, 180, and 360 μg of PEG8-2Arg NPC were compared. The lower doses showed dose-proportional day-10 concentration, and similar clearance. Higher early loss was seen with a 360-μg dose, exceeding rabbit vitreal binding capacity. No inflammation was observed. Conclusions This type of cationic NPC can safely increase residence t1/2 in a 1 to 3-week range, with dose <100 μg per mL vitreous. Human drug load may then range from 10 to 100 μg/eye, usefulness depending on individual drug potency and release rate, superimposed on extended intravitreal residence.
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Affiliation(s)
- Ignacio Melgar-Asensio
- Center for Developmental Therapeutics, Northwestern University, Evanston, Illinois, United States.,Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Irawati Kandela
- Center for Developmental Therapeutics, Northwestern University, Evanston, Illinois, United States
| | - Fraser Aird
- Center for Developmental Therapeutics, Northwestern University, Evanston, Illinois, United States
| | - Soesiawati R Darjatmoko
- Departments of Ophthalmology and Visual Sciences, Biomedical Engineering, and Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Cristobal de Los Rios
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Christine M Sorenson
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Daniel M Albert
- Department of Ophthalmology, Casey Eye Institute, Oregon Health Sciences University, Portland, Oregon, United States
| | - Nader Sheibani
- Departments of Ophthalmology and Visual Sciences, Biomedical Engineering, and Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Jack Henkin
- Center for Developmental Therapeutics, Northwestern University, Evanston, Illinois, United States
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Fang X, Bogomolovas J, Trexler C, Chen J. The BAG3-dependent and -independent roles of cardiac small heat shock proteins. JCI Insight 2019; 4:126464. [PMID: 30830872 DOI: 10.1172/jci.insight.126464] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Small heat shock proteins (sHSPs) comprise an important protein family that is ubiquitously expressed, is highly conserved among species, and has emerged as a critical regulator of protein folding. While these proteins are functionally important for a variety of tissues, an emerging field of cardiovascular research reveals sHSPs are also extremely important for maintaining normal cardiac function and regulating the cardiac stress response. Notably, numerous mutations in genes encoding sHSPs have been associated with multiple cardiac diseases. sHSPs (HSPB5, HSPB6, and HSPB8) have been described as mediating chaperone functions within the heart by interacting with the cochaperone protein BCL-2-associated anthanogene 3 (BAG3); however, recent reports indicate that sHSPs (HSPB7) can perform other BAG3-independent functions. Here, we summarize the cardiac functions of sHSPs and present the notion that cardiac sHSPs function via BAG3-dependent or -independent pathways.
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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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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: 172] [Impact Index Per Article: 28.7] [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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63
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Benndorf R, Gilmont RR, Hirano S, Ransom RF, Jungblut PR, Bommer M, Goldman JE, Welsh MJ. Small heat shock protein speciation: novel non-canonical 44 kDa HspB5-related protein species in rat and human tissues. Cell Stress Chaperones 2018; 23:813-826. [PMID: 29542021 PMCID: PMC6111085 DOI: 10.1007/s12192-018-0890-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 02/21/2018] [Accepted: 02/23/2018] [Indexed: 10/17/2022] Open
Abstract
When analyzing small stress proteins of rat and human tissues by electrophoretic methods followed by western blotting, and using the anti-HspB1/anti-HspB5 antibody clone 8A7, we unexpectedly found a protein with a molecular mass of ~44 kDa. On two-dimensional gels, this protein resolved into four distinct species. Electrophoretic and immunological evidence suggests that this 44 kDa protein is a derivative of HspB5, most likely a covalently linked HspB5 dimer. This HspB5-like 44 kDa protein (HspB5L-P44) is particularly abundant in rat heart, brain, and renal cortex and glomeruli. HspB5L-P44 was also found in human brains, including those from patients with Alexander disease, a condition distinguished by cerebral accumulation of HspB5. Gray matter of such a patient contained an elevated amount of HspB5L-P44. A spatial model of structurally ordered dimeric HspB5 α-crystallin domains reveals the exposed and adjacent position of the two peptide segments homologous to the HspB1-derived 8A7 antigen determinant peptide (epitope). This explains the observed extraordinary high avidity of the 8A7 antibody towards HspB5L-P44, as opposed to commonly used HspB5-specific antibodies which recognize other epitopes. This scenario also explains the remarkable fact that no previous study reported the existence of HspB5L-P44 species. Exposure of rat endothelial cells to UV light, an oxidative stress condition, temporarily increased HspB5L-P44, suggesting physiological regulation of the dimerization. The existence of HspB5L-P44 supports the protein speciation discourse and fits to the concept of the protein code, according to which the expression of a given gene is reflected only by the complete set of the derived protein species.
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Affiliation(s)
- Rainer Benndorf
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Robert R Gilmont
- Department of Plastic and Reconstructive Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Sahoko Hirano
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Richard F Ransom
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Peter R Jungblut
- Core Facility Protein Analysis, Max-Planck-Institute for Infection Biology, Berlin, Germany
| | - Martin Bommer
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany
| | - James E Goldman
- Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Michael J Welsh
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
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64
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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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65
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Pinheiro GMS, Ramos CHI. Initial characterization of newly identified mitochondrial and chloroplast small HSPs from sugarcane shows that these chaperones have different oligomerization states and substrate specificities. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 129:285-294. [PMID: 29909242 DOI: 10.1016/j.plaphy.2018.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 06/08/2023]
Abstract
Chaperones belonging to the small heat shock protein (sHSP) family are ubiquitous and exhibit elevated expression under stresses conditions to protect proteins against aggregation, thereby contributing to the stress tolerance of the organism. Tropical plants are constantly exposed to high temperatures, and the mechanisms by which these plants tolerate heat stress are of foremost importance to basic science as well as applied agrobiotechnology. Therefore, this study aims to characterize sHSPs from different organelles from sugarcane, an important crop that is associated with sugar and bioenergy production. An expression sequence tag database of sugarcane was searched, and sHsp genes of mitochondrial and chloroplast organelles were selected and cloned. The proteins were expressed in Escherichia coli and isolated and purified by two chromatographic steps with high purity as single species. Circular dichroism and fluorescence spectroscopy showed that both proteins were purified in their folded states with a predominant β-sheet secondary structure. Determination of the molecular weight, diffusion coefficient and Stokes radius parameters showed that both chaperones form large spherical-like oligomers in solution. The two sHSPs had different oligomeric states and substrate specificities. The mitochondrial sHSP was a 20-mer with ability to protect model substrates that differ from that of the 16-meric sHSP from chloroplasts. These results indicate that both sHSPs are key agents to protect against stress confirming the importance of the great diversity of sHSP chaperones in plants for homeostasis maintenance. Moreover, to our knowledge, this is the first report about small HSPs from sugarcane organelles.
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Affiliation(s)
| | - Carlos H I Ramos
- Chemistry Institute, UNICAMP, P.O. Box 6154, Campinas, 13083-970, SP, Brazil.
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66
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Li Y, Xu X, Qu R, Zhang G, Rajoka MSR, Shao D, Jiang C, Shi J. Heterologous expression of Oenococcus oeni sHSP20 confers temperature stress tolerance in Escherichia coli. Cell Stress Chaperones 2018; 23:653-662. [PMID: 29359265 PMCID: PMC6045537 DOI: 10.1007/s12192-018-0874-5] [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: 10/15/2017] [Revised: 12/19/2017] [Accepted: 01/03/2018] [Indexed: 12/11/2022] Open
Abstract
Small heat shock proteins (sHSPs) are heat shock proteins sized 12-43 kDa that can protect proteins from denaturation, particularly under high temperature; sHSPs thus increase the heat tolerance capability of an organisms enabling survival in adverse climates. sHSP20 is overexpressed in Oenococcus oeni in response to low temperatures. However, we found that overexpression of sHSP20 in Escherichia coli BL21 increased the microbial survival ratio at 50 °C by almost 2 h. Adding sHSP20 to the glutamate dehydrogenase solution significantly increased the stability of the enzyme at high temperature (especially at 60-70 °C), low pH values (especially below 6.0), and high concentration of metal ions of Ga2+, Zn2+, Mn2+, and Fe3+. Notably, the coexpression of sHSP20 significantly enhanced soluble expression of laccase from Phomopsis sp. XP-8 (CCTCCM209291) in E. coli without codon optimization, as well as the activity and heat stability of the expressed enzyme. In addition to the chaperone activity of sHSP20 in the gene containing host in vivo and the enzyme heat stability in vitro, our study indicated the capability of coexpression of sHSP20 to increase the efficiency of prokaryotic expression of fungal genes and the activity of expressed enzymes. Graphical abstract ᅟ.
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Affiliation(s)
- Yan Li
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Xiaoguang Xu
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Rui Qu
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Guoqiang Zhang
- College of Food Science, Agricultural and Animal Husbandry College of Tibet University, Linzhi, 860000 Xi Zang People’s Republic of China
| | - Muhammad Shahid Riaz Rajoka
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Dongyan Shao
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Chunmei Jiang
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
| | - Junling Shi
- Key Laboratory for Space Bioscience and Space Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi People’s Republic of China
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67
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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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68
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Terminal Regions Confer Plasticity to the Tetrameric Assembly of Human HspB2 and HspB3. J Mol Biol 2018; 430:3297-3310. [PMID: 29969581 PMCID: PMC6119766 DOI: 10.1016/j.jmb.2018.06.047] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/22/2018] [Accepted: 06/26/2018] [Indexed: 01/17/2023]
Abstract
Heterogeneity in small heat shock proteins (sHsps) spans multiple spatiotemporal regimes-from fast fluctuations of part of the protein, to conformational variability of tertiary structure, plasticity of the interfaces, and polydispersity of the inter-converting, and co-assembling oligomers. This heterogeneity and dynamic nature of sHsps has significantly hindered their structural characterization. Atomic coordinates are particularly lacking for vertebrate sHsps, where most available structures are of extensively truncated homomers. sHsps play important roles in maintaining protein levels in the cell and therefore in organismal health and disease. HspB2 and HspB3 are vertebrate sHsps that are found co-assembled in neuromuscular cells, and variants thereof are associated with disease. Here, we present the structure of human HspB2/B3, which crystallized as a hetero-tetramer in a 3:1 ratio. In the HspB2/B3 tetramer, the four α-crystallin domains (ACDs) assemble into a flattened tetrahedron which is pierced by two non-intersecting approximate dyads. Assembly is mediated by flexible "nuts and bolts" involving IXI/V motifs from terminal regions filling ACD pockets. Parts of the N-terminal region bind in an unfolded conformation into the anti-parallel shared ACD dimer grooves. Tracts of the terminal regions are not resolved, most likely due to their disorder in the crystal lattice. This first structure of a full-length human sHsp heteromer reveals the heterogeneous interactions of the terminal regions and suggests a plasticity that is important for the cytoprotective functions of sHsps.
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69
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Zhu Z, Reiser G. The small heat shock proteins, especially HspB4 and HspB5 are promising protectants in neurodegenerative diseases. Neurochem Int 2018; 115:69-79. [PMID: 29425965 DOI: 10.1016/j.neuint.2018.02.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/24/2018] [Accepted: 02/05/2018] [Indexed: 12/13/2022]
Abstract
Small heat shock proteins (sHsps) are a group of proteins with molecular mass between 12 and 43 kDa. Currently, 11 members of this family have been classified, namely HspB1 to HspB11. HspB1, HspB2, HspB5, HspB6, HspB7, and HspB8, which are expressed in brain have been observed to be related to the pathology of neurodegenerative diseases, including Parkinson's, Alzheimer's, Alexander's disease, multiple sclerosis, and human immunodeficiency virus-associated dementia. Specifically, sHsps interact with misfolding and damaging protein aggregates, like Glial fibrillary acidic protein in AxD, β-amyloid peptides aggregates in Alzheimer's disease, Superoxide dismutase 1 in Amyotrophic lateral sclerosis and cytosine-adenine-guanine/polyglutamine (CAG/PolyQ) in Huntington's disease, Spinocerebellar ataxia type 3, Spinal-bulbar muscular atrophy, to reduce the toxicity or increase the clearance of these protein aggregates. The degree of HspB4 expression in brain is still debated. For neuroprotective mechanisms, sHsps attenuate mitochondrial dysfunctions, reduce accumulation of misfolded proteins, block oxidative/nitrosative stress, and minimize neuronal apoptosis and neuroinflammation, which are molecular mechanisms commonly accepted to mirror the progression and development of neurodegenerative diseases. The increasing incidence of the neurodegenerative diseases enhanced search for effective approaches to rescue neural tissue from degeneration with minimal side effects. sHsps have been found to exert neuroprotective functions. HspB5 has been emphasized to reduce the paralysis in a mouse model of experimental autoimmune encephalomyelitis, providing a therapeutic basis for the disease. In this review, we discuss the current understanding of the properties and the mechanisms of protection orchestrated by sHsps in the nervous system, highlighting the promising therapeutic role of sHsps in neurodegenerative diseases.
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Affiliation(s)
- Zhihui Zhu
- Institut für Inflammation und Neurodegeneration (Neurobiochemie), Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Straße 44, 39120 Magdeburg, Germany; College of Medicine, Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Georg Reiser
- Institut für Inflammation und Neurodegeneration (Neurobiochemie), Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Straße 44, 39120 Magdeburg, Germany.
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70
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Schwartz NU, Linzer RW, Truman JP, Gurevich M, Hannun YA, Senkal CE, Obeid LM. Decreased ceramide underlies mitochondrial dysfunction in Charcot-Marie-Tooth 2F. FASEB J 2018; 32:1716-1728. [PMID: 29133339 DOI: 10.1096/fj.201701067r] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Charcot-Marie-Tooth (CMT) disease is the most commonly inherited neurologic disorder, but its molecular mechanisms remain unclear. One variant of CMT, 2F, is characterized by mutations in heat shock protein 27 (Hsp27). As bioactive sphingolipids have been implicated in neurodegenerative diseases, we sought to determine if their dysregulation is involved in CMT. Here, we show that Hsp27 knockout mice demonstrated decreases in ceramide in peripheral nerve tissue and that the disease-associated Hsp27 S135F mutant demonstrated decreases in mitochondrial ceramide. Given that Hsp27 is a chaperone protein, we examined its role in regulating ceramide synthases (CerSs), an enzyme family responsible for catalyzing generation of the sphingolipid ceramide. We determined that CerSs colocalized with Hsp27, and upon the presence of S135F mutants, CerS1 lost its colocalization with mitochondria suggesting that decreased mitochondrial ceramides result from reduced mitochondrial CerS localization rather than decreased CerS activity. Mitochondria in mutant cells appeared larger with increased interconnectivity. Furthermore, mutant cell lines demonstrated decreased mitochondrial respiratory function and increased autophagic flux. Mitochondrial structural and functional changes were recapitulated by blocking ceramide generation pharmacologically. These results suggest that mutant Hsp27 decreases mitochondrial ceramide levels, producing structural and functional changes in mitochondria leading to neuronal degeneration.-Schwartz, N. U., Linzer, R. W., Truman, J.-P., Gurevich, M., Hannun, Y. A., Senkal, C. E., Obeid, L. M. Decreased ceramide underlies mitochondrial dysfunction in Charcot-Marie-Tooth 2F.
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Affiliation(s)
- Nicholas U Schwartz
- Department of Neurobiology and Behavior, Stony Brook University School of Medicine, Stony Brook, New York, USA
| | - Ryan W Linzer
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, New York, USA
| | - Jean-Philip Truman
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, New York, USA
| | - Mikhail Gurevich
- Department of Pharmacology, Stony Brook University School of Medicine, Stony Brook, New York, USA.,Department of Orthopaedics, Stony Brook University School of Medicine, Stony Brook, New York, USA; and
| | - Yusuf A Hannun
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, New York, USA
| | - Can E Senkal
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, New York, USA
| | - Lina M Obeid
- Department of Medicine, Stony Brook University School of Medicine, Stony Brook, New York, USA.,Northport Veterans Affairs Medical Center, Northport, New York, USA
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71
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Dauter Z, Jaskolski M. On the helical arrangements of protein molecules. Protein Sci 2017; 27:643-652. [PMID: 29194829 DOI: 10.1002/pro.3356] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 11/22/2017] [Accepted: 11/28/2017] [Indexed: 11/09/2022]
Abstract
Helical structures are prevalent in biology. In the PDB, there are many examples where protein molecules are helically arranged, not only according to strict crystallographic screw axes but also according to approximate noncrystallographic screws. The preponderance of such screws is rather striking as helical arrangements in crystals must preserve an integer number of subunits per turn, while intuition and simple packing arguments would seem to favor fractional helices. The article provides insights into such questions, based on stereochemistry, trigonometry, and topology, and illustrates the findings with concrete PDB structures. Updated statistics of Sohncke space groups in the PDB are also presented.
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Affiliation(s)
- Zbigniew Dauter
- Synchrotron Radiation Research Section, MCL, National Cancer Institute, Argonne National Laboratory, Argonne, Illinois, 60439
| | - Mariusz Jaskolski
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Poznan, 61-614, Poland.,Center for Biocrystallographic Research, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, 61-704, Poland
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72
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Clouser AF, Klevit RE. pH-dependent structural modulation is conserved in the human small heat shock protein HSBP1. Cell Stress Chaperones 2017; 22:569-575. [PMID: 28332148 PMCID: PMC5465033 DOI: 10.1007/s12192-017-0783-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 10/19/2022] Open
Abstract
The holdase activity and oligomeric propensity of human small heat shock proteins (sHSPs) are regulated by environmental factors. However, atomic-level details are lacking for the mechanisms by which stressors alter sHSP responses. We previously demonstrated that regulation of HSPB5 is mediated by a single conserved histidine over a physiologically relevant pH range of 6.5-7.5. Here, we demonstrate that HSPB1 responds to pH via a similar mechanism through pH-dependent structural changes that are induced via protonation of the structurally analogous histidine. Results presented here show that acquisition of a positive charge, either by protonation of His124 or its substitution by lysine, reduces the stability of the dimer interface of the α-crystallin domain, increases oligomeric size, and modestly increases chaperone activity. Our results suggest a conserved mechanism of pH-dependent structural regulation among the human sHSPs that possess the conserved histidine, although the functional consequences of the structural modulations vary for different sHSPs.
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Affiliation(s)
- Amanda F Clouser
- Department of Biochemistry, University of Washington, Seattle, WA, 98195, USA
| | - Rachel E Klevit
- Department of Biochemistry, University of Washington, Seattle, WA, 98195, USA.
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73
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Dabbaghizadeh A, Finet S, Morrow G, Moutaoufik MT, Tanguay RM. Oligomeric structure and chaperone-like activity of Drosophila melanogaster mitochondrial small heat shock protein Hsp22 and arginine mutants in the alpha-crystallin domain. Cell Stress Chaperones 2017; 22:577-588. [PMID: 28389817 PMCID: PMC5465034 DOI: 10.1007/s12192-017-0784-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 02/24/2017] [Accepted: 02/28/2017] [Indexed: 01/17/2023] Open
Abstract
The structure and chaperone function of DmHsp22WT, a small Hsp of Drosophila melanogaster localized within mitochondria were examined. Mutations of conserved arginine mutants within the alpha-crystallin domain (ACD) domain (R105G, R109G, and R110G) were introduced, and their effects on oligomerization and chaperone function were assessed. Arginine to glycine mutations do not induce significant changes in tryptophan fluorescence, and the mutated proteins form oligomers that are of equal or smaller size than the wild-type protein. They all form oligomer with one single peak as determined by size exclusion chromatography. While all mutants demonstrate the same efficiency as the DmHsp22WT in a DTT-induced insulin aggregation assay, all are more efficient chaperones to prevent aggregation of malate dehydrogenase. Arginine mutants of DmHsp22 are efficient chaperones to retard aggregation of CS and Luc. In summary, this study shows that mutations of arginine to glycine in DmHsp22 ACD induce a number of structural changes, some of which differ from those described in mammalian sHsps. Interestingly, only the R110G-DmHsp22 mutant, and not the expected R109G equivalent to human R140-HspB1, R116-HspB4, and R120-HspB5, showed different structural properties compared with the DmHsp22WT.
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Affiliation(s)
- Afrooz Dabbaghizadeh
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Faculté de médecine, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, Québec, G1V 0A6, Canada
| | - Stéphanie Finet
- IMPMC UMR7590, CNRS, Sorbonne-Universités, MNHN, IRD, 4 place Jussieu, Paris, France
| | - Genevieve Morrow
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Faculté de médecine, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, Québec, G1V 0A6, Canada
| | - Mohamed Taha Moutaoufik
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Faculté de médecine, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, Québec, G1V 0A6, Canada
| | - Robert M Tanguay
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Faculté de médecine, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, Québec, G1V 0A6, Canada.
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74
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Carver JA, Grosas AB, Ecroyd H, Quinlan RA. The functional roles of the unstructured N- and C-terminal regions in αB-crystallin and other mammalian small heat-shock proteins. Cell Stress Chaperones 2017; 22:627-638. [PMID: 28391594 PMCID: PMC5465038 DOI: 10.1007/s12192-017-0789-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/06/2017] [Accepted: 03/16/2017] [Indexed: 01/18/2023] Open
Abstract
Small heat-shock proteins (sHsps), such as αB-crystallin, are one of the major classes of molecular chaperone proteins. In vivo, under conditions of cellular stress, sHsps are the principal defence proteins that prevent large-scale protein aggregation. Progress in determining the structure of sHsps has been significant recently, particularly in relation to the conserved, central and β-sheet structured α-crystallin domain (ACD). However, an understanding of the structure and functional roles of the N- and C-terminal flanking regions has proved elusive mainly because of their unstructured and dynamic nature. In this paper, we propose functional roles for both flanking regions, based around three properties: (i) they act in a localised crowding manner to regulate interactions with target proteins during chaperone action, (ii) they protect the ACD from deleterious amyloid fibril formation and (iii) the flexibility of these regions, particularly at the extreme C-terminus in mammalian sHsps, provides solubility for sHsps under chaperone and non-chaperone conditions. In the eye lens, these properties are highly relevant as the crystallin proteins, in particular the two sHsps αA- and αB-crystallin, are present at very high concentrations.
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Affiliation(s)
- John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT, 2601, Australia.
| | - Aidan B Grosas
- Research School of Chemistry, The Australian National University, Acton, ACT, 2601, Australia
| | - Heath Ecroyd
- School of Biological Sciences and the Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Roy A Quinlan
- Department of Biosciences, Durham University, Durham, DH1 3LE, UK
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75
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Moutaoufik MT, Morrow G, Maaroufi H, Férard C, Finet S, Tanguay RM. Oligomerization and chaperone-like activity of Drosophila melanogaster small heat shock protein DmHsp27 and three arginine mutants in the alpha-crystallin domain. Cell Stress Chaperones 2017; 22:455-466. [PMID: 27933579 PMCID: PMC5465024 DOI: 10.1007/s12192-016-0748-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 11/30/2022] Open
Abstract
The small Hsp DmHsp27 from Drosophila melanogaster is one of the few small heat shock proteins (sHsps) found within the nucleus. We report that its dimerization is independent of disulfide bond formation and seems to rely on salt bridges. Unlike metazoan sHsps, DmHsp27 forms two populations of oligomers not in equilibrium. Mutations at highly conserved arginine residues in mammalian sHsps have been reported to be associated with protein conformational defects and intracellular aggregation. Independent mutation of three highly conserved arginines (R122, R131, and R135) to glycine in DmHsp27 results in only one population of higher molecular weight form. In vitro, the chaperone-like activity of wild-type DmHsp27 was comparable with that of its two isolated populations and to the single population of the R122G, R131G, and R135G using luciferase as substrate. However, using insulin, the chaperone-like activity of wild-type DmHsp27 was lower than that of R122G and R131G mutants. Altogether, the results characterize wild-type DmHsp27 and its alpha-crystallin domain (ACD) arginine mutants and may give insight into protection mechanism of sHsps.
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Affiliation(s)
- Mohamed Taha Moutaoufik
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, G1V 0A6, Canada
| | - Geneviève Morrow
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, G1V 0A6, Canada
| | - Halim Maaroufi
- Plate-forme de bio-informatique, Institut de biologie intégrative et des systèmes (IBIS), Université Laval, Québec, G1V 0A6, Canada
| | - Céline Férard
- IMPMC UMR7590, CNRS, UPMC Paris 6, 4 place Jussieu, Paris, France
| | - Stéphanie Finet
- IMPMC UMR7590, CNRS, UPMC Paris 6, 4 place Jussieu, Paris, France
| | - Robert M Tanguay
- Laboratoire de génétique cellulaire et développementale, Département de biologie moléculaire, de biochimie médicale et de pathologie, Institut de biologie intégrative et des systèmes (IBIS) and PROTEO, Université Laval, Québec, G1V 0A6, Canada.
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76
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Brodehl A, Gaertner-Rommel A, Klauke B, Grewe SA, Schirmer I, Peterschröder A, Faber L, Vorgerd M, Gummert J, Anselmetti D, Schulz U, Paluszkiewicz L, Milting H. The novel αB-crystallin (CRYAB) mutation p.D109G causes restrictive cardiomyopathy. Hum Mutat 2017; 38:947-952. [PMID: 28493373 DOI: 10.1002/humu.23248] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 05/03/2017] [Accepted: 05/03/2017] [Indexed: 11/09/2022]
Abstract
Restrictive cardiomyopathy (RCM) is a rare heart disease characterized by diastolic dysfunction and atrial enlargement. The genetic etiology of RCM is not completely known. We identified by a next-generation sequencing panel the novel CRYAB missense mutation c.326A>G, p.D109G in a small family with RCM in combination with skeletal myopathy with an early onset of the disease. CRYAB encodes αB-crystallin, a member of the small heat shock protein family, which is highly expressed in cardiac and skeletal muscle. In addition to in silico prediction analysis, our structural analysis of explanted myocardial tissue of a mutation carrier as well as in vitro cell transfection experiments revealed abnormal protein aggregation of mutant αB-crystallin and desmin, supporting the deleterious effect of this novel mutation. In conclusion, CRYAB appears to be a novel RCM gene, which might have relevance for the molecular diagnosis and the genetic counseling of further affected families in the future.
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Affiliation(s)
- Andreas Brodehl
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Anna Gaertner-Rommel
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Bärbel Klauke
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Simon Andre Grewe
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Ilona Schirmer
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Andreas Peterschröder
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Institute of Radiology, Nuclear Medicine and Molecular Imaging, Bad Oeynhausen, Germany
| | - Lothar Faber
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Clinic of Cardiology, Bad Oeynhausen, Germany
| | - Matthias Vorgerd
- Department of Neurology, BG-University Hospital Bergmannsheil, Bochum, Germany
| | - Jan Gummert
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Dario Anselmetti
- Bielefeld University and Bielefeld Institute for Nanoscience (BINAS), Faculty of Physics, Experimental Biophysics and Applied Nanoscience, Bielefeld, Germany
| | - Uwe Schulz
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Lech Paluszkiewicz
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
| | - Hendrik Milting
- Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, Erich and Hanna Klessmann Institute for Cardiovascular Research & Development (EHKI), Bad Oeynhausen, Germany
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77
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Heirbaut M, Lermyte F, Martin EM, Beelen S, Sobott F, Strelkov SV, Weeks SD. Specific sequences in the N-terminal domain of human small heat-shock protein HSPB6 dictate preferential hetero-oligomerization with the orthologue HSPB1. J Biol Chem 2017; 292:9944-9957. [PMID: 28487364 DOI: 10.1074/jbc.m116.773515] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/20/2017] [Indexed: 12/17/2022] Open
Abstract
Small heat-shock proteins (sHSPs) are a conserved group of molecular chaperones with important roles in cellular proteostasis. Although sHSPs are characterized by their small monomeric weight, they typically assemble into large polydisperse oligomers that vary in both size and shape but are principally composed of dimeric building blocks. These assemblies can include different sHSP orthologues, creating additional complexity that may affect chaperone activity. However, the structural and functional properties of such hetero-oligomers are poorly understood. We became interested in hetero-oligomer formation between human heat-shock protein family B (small) member 1 (HSPB1) and HSPB6, which are both highly expressed in skeletal muscle. When mixed in vitro, these two sHSPs form a polydisperse oligomer array composed solely of heterodimers, suggesting preferential association that is determined at the monomer level. Previously, we have shown that the sHSP N-terminal domains (NTDs), which have a high degree of intrinsic disorder, are essential for the biased formation. Here we employed iterative deletion mapping to elucidate how the NTD of HSPB6 influences its preferential association with HSPB1 and show that this region has multiple roles in this process. First, the highly conserved motif RLFDQXFG is necessary for subunit exchange among oligomers. Second, a site ∼20 residues downstream of this motif determines the size of the resultant hetero-oligomers. Third, a region unique to HSPB6 dictates the preferential formation of heterodimers. In conclusion, the disordered NTD of HSPB6 helps regulate the size and stability of hetero-oligomeric complexes, indicating that terminal sHSP regions define the assembly properties of these proteins.
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Affiliation(s)
- Michelle Heirbaut
- From the Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Frederik Lermyte
- the Biomolecular and Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium, and
| | - Esther M Martin
- the Biomolecular and Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium, and.,the Astbury Centre for Structural Molecular Biology and
| | - Steven Beelen
- From the Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Frank Sobott
- the Biomolecular and Analytical Mass Spectrometry Group, Department of Chemistry, University of Antwerp, 2020 Antwerp, Belgium, and.,the Astbury Centre for Structural Molecular Biology and.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, United Kingdom
| | - Sergei V Strelkov
- From the Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium,
| | - Stephen D Weeks
- From the Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium,
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78
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Fonseca EMB, Scorsato V, Dos Santos ML, Júnior AT, Tada SFS, Dos Santos CA, de Toledo MAS, de Souza AP, Polikarpov I, Aparicio R. Crystal structure of a small heat-shock protein from Xylella fastidiosa reveals a distinct high-order structure. Acta Crystallogr F Struct Biol Commun 2017; 73:222-227. [PMID: 28368281 PMCID: PMC5379172 DOI: 10.1107/s2053230x17004101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/14/2017] [Indexed: 11/10/2022] Open
Abstract
Citrus variegated chlorosis is a disease that attacks economically important citrus plantations and is caused by the plant-pathogenic bacterium Xylella fastidiosa. In this work, the structure of a small heat-shock protein from X. fastidiosa (XfsHSP17.9) is reported. The high-order structures of small heat-shock proteins from other organisms are arranged in the forms of double-disc, hollow-sphere or spherical assemblies. Unexpectedly, the structure reported here reveals a high-order architecture forming a nearly square cavity.
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Affiliation(s)
- Emanuella Maria Barreto Fonseca
- Laboratory of Structural Biology and Crystallography, Institute of Chemistry, University of Campinas, CP6154, 13083-970 Campinas-SP, Brazil
| | - Valéria Scorsato
- Laboratory of Structural Biology and Crystallography, Institute of Chemistry, University of Campinas, CP6154, 13083-970 Campinas-SP, Brazil
| | - Marcelo Leite Dos Santos
- Laboratory of Structural Biology and Crystallography, Institute of Chemistry, University of Campinas, CP6154, 13083-970 Campinas-SP, Brazil
| | - Atilio Tomazini Júnior
- Molecular Biotechnology Group, Department of Physics and Interdisciplinary Science, Sao Carlos Institute of Physics (IFSC), University of Sao Paulo (USP), Avenida Trabalhador São-carlense 400, Parque Arnold Schimidt, 13566-590 São Carlos-SP, Brazil
| | - Susely Ferraz Siqueira Tada
- Laboratory of Molecular and Genetic Analysis, Center for Molecular Biology and Genetic Engineering, Institute of Biology, University of Campinas, CP6010, 13083-875 Campinas-SP, Brazil
| | - Clelton Aparecido Dos Santos
- Laboratory of Molecular and Genetic Analysis, Center for Molecular Biology and Genetic Engineering, Institute of Biology, University of Campinas, CP6010, 13083-875 Campinas-SP, Brazil
| | - Marcelo Augusto Szymanski de Toledo
- Laboratory of Molecular and Genetic Analysis, Center for Molecular Biology and Genetic Engineering, Institute of Biology, University of Campinas, CP6010, 13083-875 Campinas-SP, Brazil
| | - Anete Pereira de Souza
- Laboratory of Molecular and Genetic Analysis, Center for Molecular Biology and Genetic Engineering, Institute of Biology, University of Campinas, CP6010, 13083-875 Campinas-SP, Brazil
| | - Igor Polikarpov
- Molecular Biotechnology Group, Department of Physics and Interdisciplinary Science, Sao Carlos Institute of Physics (IFSC), University of Sao Paulo (USP), Avenida Trabalhador São-carlense 400, Parque Arnold Schimidt, 13566-590 São Carlos-SP, Brazil
| | - Ricardo Aparicio
- Laboratory of Structural Biology and Crystallography, Institute of Chemistry, University of Campinas, CP6154, 13083-970 Campinas-SP, Brazil
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79
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Rutsdottir G, Härmark J, Weide Y, Hebert H, Rasmussen MI, Wernersson S, Respondek M, Akke M, Højrup P, Koeck PJB, Söderberg CAG, Emanuelsson C. Structural model of dodecameric heat-shock protein Hsp21: Flexible N-terminal arms interact with client proteins while C-terminal tails maintain the dodecamer and chaperone activity. J Biol Chem 2017; 292:8103-8121. [PMID: 28325834 PMCID: PMC5427286 DOI: 10.1074/jbc.m116.766816] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/16/2017] [Indexed: 01/14/2023] Open
Abstract
Small heat-shock proteins (sHsps) prevent aggregation of thermosensitive client proteins in a first line of defense against cellular stress. The mechanisms by which they perform this function have been hard to define due to limited structural information; currently, there is only one high-resolution structure of a plant sHsp published, that of the cytosolic Hsp16.9. We took interest in Hsp21, a chloroplast-localized sHsp crucial for plant stress resistance, which has even longer N-terminal arms than Hsp16.9, with a functionally important and conserved methionine-rich motif. To provide a framework for investigating structure-function relationships of Hsp21 and understanding these sequence variations, we developed a structural model of Hsp21 based on homology modeling, cryo-EM, cross-linking mass spectrometry, NMR, and small-angle X-ray scattering. Our data suggest a dodecameric arrangement of two trimer-of-dimer discs stabilized by the C-terminal tails, possibly through tail-to-tail interactions between the discs, mediated through extended IXVXI motifs. Our model further suggests that six N-terminal arms are located on the outside of the dodecamer, accessible for interaction with client proteins, and distinct from previous undefined or inwardly facing arms. To test the importance of the IXVXI motif, we created the point mutant V181A, which, as expected, disrupts the Hsp21 dodecamer and decreases chaperone activity. Finally, our data emphasize that sHsp chaperone efficiency depends on oligomerization and that client interactions can occur both with and without oligomer dissociation. These results provide a generalizable workflow to explore sHsps, expand our understanding of sHsp structural motifs, and provide a testable Hsp21 structure model to inform future investigations.
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Affiliation(s)
| | - Johan Härmark
- the School of Technology and Health, KTH/Royal Institute of Technology and Department of Biosciences and Nutrition, Karolinska Institutet, SE-171 77 Stockholm, Sweden, and
| | - Yoran Weide
- From the Departments of Biochemistry and Structural Biology and
| | - Hans Hebert
- the School of Technology and Health, KTH/Royal Institute of Technology and Department of Biosciences and Nutrition, Karolinska Institutet, SE-171 77 Stockholm, Sweden, and
| | - Morten I Rasmussen
- the Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense, Denmark
| | | | | | | | - Peter Højrup
- the Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense, Denmark
| | - Philip J B Koeck
- the School of Technology and Health, KTH/Royal Institute of Technology and Department of Biosciences and Nutrition, Karolinska Institutet, SE-171 77 Stockholm, Sweden, and
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80
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Lyon YA, Sabbah GM, Julian RR. Identification of Sequence Similarities among Isomerization Hotspots in Crystallin Proteins. J Proteome Res 2017; 16:1797-1805. [PMID: 28234481 PMCID: PMC5387677 DOI: 10.1021/acs.jproteome.7b00073] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The eye lens crystallins represent
an ideal target for studying
the effects of aging on protein structure. Herein we examine separately
the water-soluble (WS) and water-insoluble (WI) crystallin fractions
and identify sites of isomerization and epimerization. Both collision-induced
dissociation and radical-directed dissociation are needed for detection
of these non-mass-shifting post-translational modifications. Isomerization
levels differ significantly between the WS and the WI fractions from
sheep, pig, and cow eye lenses. Residues that are most susceptible
to isomerization are identified site-specifically and are found to
reside in structurally disordered regions. However, isomerization
in structured domains, although less common, often yields more dramatic
effects on solubility. Numerous isomerization hotspots were also identified
and occur in regions with aspartic acid and serine repeats. For example, 128KMEIVDDDVPSLW140 in βB3
crystallin contains three sequential aspartic acid residues and is
isomerized heavily in the WI fractions, while it is not modified at
all in the WS fractions. Potential causes for enhanced isomerization
at sites with acidic residue repeats are presented. The importance
of acidic residue repeats extends beyond the lens, as they are found
in many other long-lived proteins associated with disease.
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Affiliation(s)
- Yana A Lyon
- Department of Chemistry, University of California , Riverside, 501 Big Springs Road, Riverside, California 92521, United States
| | - Georgette M Sabbah
- Department of Chemistry, University of California , Riverside, 501 Big Springs Road, Riverside, California 92521, United States
| | - Ryan R Julian
- Department of Chemistry, University of California , Riverside, 501 Big Springs Road, Riverside, California 92521, United States
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81
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Sluchanko NN, Beelen S, Kulikova AA, Weeks SD, Antson AA, Gusev NB, Strelkov SV. Structural Basis for the Interaction of a Human Small Heat Shock Protein with the 14-3-3 Universal Signaling Regulator. Structure 2017; 25:305-316. [PMID: 28089448 PMCID: PMC5321513 DOI: 10.1016/j.str.2016.12.005] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/14/2016] [Accepted: 12/12/2016] [Indexed: 12/31/2022]
Abstract
By interacting with hundreds of protein partners, 14-3-3 proteins coordinate vital cellular processes. Phosphorylation of the small heat shock protein, HSPB6, within its intrinsically disordered N-terminal domain activates its interaction with 14-3-3, ultimately triggering smooth muscle relaxation. After analyzing the binding of an HSPB6-derived phosphopeptide to 14-3-3 using isothermal calorimetry and X-ray crystallography, we have determined the crystal structure of the complete assembly consisting of the 14-3-3 dimer and full-length HSPB6 dimer and further characterized this complex in solution using fluorescence spectroscopy, small-angle X-ray scattering, and limited proteolysis. We show that selected intrinsically disordered regions of HSPB6 are transformed into well-defined conformations upon the interaction, whereby an unexpectedly asymmetric structure is formed. This structure provides the first atomic resolution snapshot of a human small HSP in functional state, explains how 14-3-3 proteins sequester their regulatory partners, and can inform the design of small-molecule interaction modifiers to be used as myorelaxants.
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Affiliation(s)
- Nikolai N Sluchanko
- Laboratory of Structural Biochemistry of Proteins, A.N. Bach Institute of Biochemistry, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences, 119071 Moscow, Russia.
| | - Steven Beelen
- Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Alexandra A Kulikova
- Laboratory of Protein Conformational Polymorphism in Health and Disease, Engelhardt Institute of Molecular Biology, 119991 Moscow, Russia
| | - Stephen D Weeks
- Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Alfred A Antson
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5YW, UK
| | - Nikolai B Gusev
- Department of Biochemistry, School of Biology, Moscow State University, 119991 Moscow, Russia
| | - Sergei V Strelkov
- Laboratory for Biocrystallography, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium.
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82
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Tikhomirova TS, Selivanova OM, Galzitskaya OV. α-Crystallins are small heat shock proteins: Functional and structural properties. BIOCHEMISTRY (MOSCOW) 2017; 82:106-121. [DOI: 10.1134/s0006297917020031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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83
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The Potential Functions of Small Heat Shock Proteins in the Uterine Musculature during Pregnancy. ADVANCES IN ANATOMY, EMBRYOLOGY, AND CELL BIOLOGY 2017; 222:95-116. [PMID: 28389752 DOI: 10.1007/978-3-319-51409-3_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The small heat shock protein B (HSPB) family is comprised of eleven members with many being induced by physiological stressors. In addition to being molecular chaperones, it is clear these proteins also play important roles in cell death regulation, cytoskeletal rearrangements, and immune system activation. These processes are important for the uterine smooth muscle or myometrium during pregnancy as it changes from a quiescent tissue, during the majority of pregnancy, to a powerful and contractile tissue at labor. The initiation and progression of labor within the myometrium also appears to require an inflammatory response as it is infiltrated by immune cells and it produces pro-inflammatory mediators. This chapter summarizes current knowledge on the expression of HSPB family members in the myometrium during pregnancy and speculates on the possible roles of these proteins during myometrial programming and transformation of the myometrium into a possible immune regulatory tissue.
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84
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Nefedova VV, Muranova LK, Sudnitsyna MV, Ryzhavskaya AS, Gusev NB. Small Heat Shock Proteins and Distal Hereditary Neuropathies. BIOCHEMISTRY (MOSCOW) 2016; 80:1734-47. [PMID: 26878578 DOI: 10.1134/s000629791513009x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Classification of small heat shock proteins (sHsp) is presented and processes regulated by sHsp are described. Symptoms of hereditary distal neuropathy are described and the genes whose mutations are associated with development of this congenital disease are listed. The literature data and our own results concerning physicochemical properties of HspB1 mutants associated with Charcot-Marie-Tooth disease are analyzed. Mutations of HspB1, associated with hereditary motor neuron disease, can be accompanied by change of the size of HspB1 oligomers, by decreased stability under unfavorable conditions, by changes in the interaction with protein partners, and as a rule by decrease of chaperone-like activity. The largest part of these mutations is accompanied by change of oligomer stability (that can be either increased or decreased) or by change of intermonomer interaction inside an oligomer. Data on point mutation of HspB3 associated with axonal neuropathy are presented. Data concerning point mutations of Lys141 of HspB8 and those associated with hereditary neuropathy and different forms of Charcot-Marie-Tooth disease are analyzed. It is supposed that point mutations of sHsp associated with distal neuropathies lead either to loss of function (for instance, decrease of chaperone-like activity) or to gain of harmful functions (for instance, increase of interaction with certain protein partners).
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Affiliation(s)
- V V Nefedova
- Lomonosov Moscow State University, Faculty of Biology, Moscow, 119991, Russia.
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85
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Heirbaut M, Lermyte F, Martin EM, Beelen S, Verschueren T, Sobott F, Strelkov SV, Weeks SD. The preferential heterodimerization of human small heat shock proteins HSPB1 and HSPB6 is dictated by the N-terminal domain. Arch Biochem Biophys 2016; 610:41-50. [PMID: 27717639 DOI: 10.1016/j.abb.2016.10.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/13/2016] [Accepted: 10/03/2016] [Indexed: 01/13/2023]
Abstract
Small heat shock proteins are ATP-independent molecular chaperones. Their function is to bind partially unfolded proteins under stress conditions. In vivo, members of this chaperone family are known to preferentially assemble together forming large, polydisperse heterooligomers. The exact molecular mechanisms that drive specific heteroassociation are currently unknown. Here we study the oligomers formed between human HSPB1 and HSPB6. Using small-angle X-ray scattering we could characterize two distinct heterooligomeric species present in solution. By employing native mass spectrometry we show that such assemblies are formed purely from heterodimeric building blocks, in line with earlier cross-linking studies. Crucially, a detailed analysis of truncation variants reveals that the preferential association between these two sHSPs is solely mediated by their disordered N-terminal domains.
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Affiliation(s)
- Michelle Heirbaut
- Laboratory for Biocrystallography, Dept. of Pharmaceutical and Pharmacological Sciences, KU Leuven, Belgium
| | - Frederik Lermyte
- Biomolecular and Analytical Mass Spectrometry Group, Dept. of Chemistry, University of Antwerp, Belgium; Centre for Proteomics, University of Antwerp, Belgium
| | - Esther M Martin
- Biomolecular and Analytical Mass Spectrometry Group, Dept. of Chemistry, University of Antwerp, Belgium
| | - Steven Beelen
- Laboratory for Biocrystallography, Dept. of Pharmaceutical and Pharmacological Sciences, KU Leuven, Belgium
| | - Tim Verschueren
- Biomolecular and Analytical Mass Spectrometry Group, Dept. of Chemistry, University of Antwerp, Belgium
| | - Frank Sobott
- Biomolecular and Analytical Mass Spectrometry Group, Dept. of Chemistry, University of Antwerp, Belgium
| | - Sergei V Strelkov
- Laboratory for Biocrystallography, Dept. of Pharmaceutical and Pharmacological Sciences, KU Leuven, Belgium.
| | - Stephen D Weeks
- Laboratory for Biocrystallography, Dept. of Pharmaceutical and Pharmacological Sciences, KU Leuven, Belgium.
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86
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Skinner C, Miraldi Utz V. Pharmacological approaches to restoring lens transparency: Real world applications. Ophthalmic Genet 2016; 38:201-205. [PMID: 27648776 DOI: 10.1080/13816810.2016.1214971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Cataract is the most common cause of blindness and a major cause of visual impairment worldwide. As the world's population ages, cataract-induced visual impairment is of increasing prevalence, and treatment is limited to those with access to surgical care. While cataracts are mainly a disease of the elderly, infantile cataracts lead to lifelong visual impairment if untreated. Even in those with surgical treatment early in life, visual prognosis is often guarded. Consequently, there is an increasing impetus for alternative therapeutic modalities. Makley and Zhao utilize two different experimental approaches to identify novel pharmacological substances able to improve lens transparency by reducing aggregation of crystalline proteins. These data support an alternative to surgical correction that may be applied to adult patients without access to surgical care as well as address the unique challenges of infantile cataracts.
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Affiliation(s)
- Cassandra Skinner
- a University of Cincinnati College of Medicine , Cincinnati , Ohio , USA
| | - Virginia Miraldi Utz
- a University of Cincinnati College of Medicine , Cincinnati , Ohio , USA.,b Abrahamson Pediatric Eye Institute, Cincinnati Children's Hospital Medical Center , Cincinnati , Ohio , USA.,c Department of Ophthalmology , University of Cincinnati , Cincinnati , Ohio , USA
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87
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Gonçalves DC, Marin TM, Pereira MBM, Santos AM, Paes Leme AF, Franchini KG. αB-Crystallin interacts and attenuates the tyrosine phosphatase activity of Shp2 in cardiomyocytes under mechanical stress. FEBS Lett 2016; 590:2232-40. [DOI: 10.1002/1873-3468.12235] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 05/30/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Danieli C. Gonçalves
- Brazilian Biosciences National Laboratory; Campinas Brazil
- Institute of Biology; State University of Campinas; Campinas São Paulo Brazil
| | | | - Michelle B. M. Pereira
- Medicine Department; Federal University of Juiz de Fora; Governador Valadares Minas Gerais Brazil
| | - Aline M. Santos
- Institute of Biology; State University of Campinas; Campinas São Paulo Brazil
| | | | - Kleber G. Franchini
- Brazilian Biosciences National Laboratory; Campinas Brazil
- School of Medicine; State University of Campinas; Campinas São Paulo Brazil
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88
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Jaspard E, Hunault G. sHSPdb: a database for the analysis of small Heat Shock Proteins. BMC PLANT BIOLOGY 2016; 16:135. [PMID: 27297221 PMCID: PMC4906601 DOI: 10.1186/s12870-016-0820-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/24/2016] [Indexed: 05/29/2023]
Abstract
BACKGROUND small Heat Shock Proteins (sHSP) is a wide proteins family. SHSP are found in all kingdoms and they play critical roles in plant stress tolerance mechanisms (as well as in pathogenic microorganisms and are implicated in human diseases). RESULTS sHSPdb (small Heat Shock Proteins database) is an integrated resource containing non-redundant, full-length and curated sequences of sHSP, classified on the basis of amino acids motifs and physico-chemical properties. sHSPdb gathers data about sHSP defined by various databases (Uniprot, PFAM, CDD, InterPro). It provides a browser interface for retrieving information from the whole database and a search interface using various criteria for retrieving a refined subset of entries. Physicochemical properties, amino acid composition and combinations are calculated for each entry. sHSPdb provides automatic statistical analysis of all sHSP properties. Among various possibilities, sHSPdb allows BLAST searches, alignment of selected sequences and submission of sequences. CONCLUSIONS sHSPdb is a new database containing information about sHSP from all kingdoms. sHSPdb provides a classification of sHSP, as well as tools and data for the analysis of the structure - function relationships of sHSP. Data are mainly related to various physico-chemical properties of the amino acids sequences of sHSP. sHSPdb is accessible at http://forge.info.univ-angers.fr/~gh/Shspdb/index.php .
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Affiliation(s)
- Emmanuel Jaspard
- Université d'Angers, UMR 1345 IRHS, SFR 4207 QUASAV, Angers, France.
- INRA, UMR 1345 IRHS, Beaucouzé, France.
- Agrocampus-Ouest, UMR 1345 IRHS, Angers, France.
| | - Gilles Hunault
- Université d'Angers, Laboratoire d'Hémodynamique, Interaction Fibrose et Invasivité tumorale hépatique, UPRES 3859, IFR 132, F-49045, Angers, France
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89
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Sehgal SA, Mannan S, Ali S. Pharmacoinformatic and molecular docking studies reveal potential novel antidepressants against neurodegenerative disorders by targeting HSPB8. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:1605-18. [PMID: 27226709 PMCID: PMC4866741 DOI: 10.2147/dddt.s101929] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Charcot-Marie-Tooth (CMT) disease is an inherited peripheral neuromuscular disorder characterized by length-dependent and progressive degeneration of peripheral nerves, leading to muscular weakness. Research has shown that mutated HSPB8 may be responsible for depression, neurodegenerative disorders, and improper functioning of peripheral nerves, resulting in neuromuscular disorders like CMT. In the current work, a hybrid approach of virtual screening and molecular docking studies was followed by homology modeling and pharmacophore identification. Detailed screening analyses were carried out by 2-D similarity search against prescribed antidepressant drugs with physicochemical properties. LigandScout was employed to ascertain novel molecules and pharmacophore properties. In this study, we report three novel compounds that showed maximum binding affinity with HSPB8. Docking analysis elucidated that Met37, Ser57, Ser58, Trp60, Thr63, Thr114, Lys115, Asp116, Gly117, Val152, Val154, Leu186, Asp189, Ser190, Gln191, and Glu192 are critical residues for ligand-receptor interactions. Our analyses suggested paroxetine as a potent compound for targeting HSPB8. Selected compounds have more effective energy scores than the selected drug analogs. Additionally, site-directed mutagenesis could be significant for further analysis of the binding pocket. The novel findings based on an in silico approach may be momentous for potent drug design against depression and CMT.
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Affiliation(s)
- Sheikh Arslan Sehgal
- Department of Bioscience, COMSATS Institute of Information Technology, Sahiwal, Pakistan; State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, People's Republic of China; University of Chinese Academy of Sciences, Beijing, People's Republic of China; Department of Bioinformatics and Biotechnology, International Islamic University, Islamabad, Pakistan
| | - Shazia Mannan
- Department of Bioscience, COMSATS Institute of Information Technology, Sahiwal, Pakistan
| | - Sannia Ali
- Department of Bioscience, COMSATS Institute of Information Technology, Sahiwal, Pakistan
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90
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Piri N, Kwong JMK, Gu L, Caprioli J. Heat shock proteins in the retina: Focus on HSP70 and alpha crystallins in ganglion cell survival. Prog Retin Eye Res 2016; 52:22-46. [PMID: 27017896 PMCID: PMC4842330 DOI: 10.1016/j.preteyeres.2016.03.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 03/14/2016] [Accepted: 03/22/2016] [Indexed: 10/22/2022]
Abstract
Heat shock proteins (HSPs) belong to a superfamily of stress proteins that are critical constituents of a complex defense mechanism that enhances cell survival under adverse environmental conditions. Cell protective roles of HSPs are related to their chaperone functions, antiapoptotic and antinecrotic effects. HSPs' anti-apoptotic and cytoprotective characteristics, their ability to protect cells from a variety of stressful stimuli, and the possibility of their pharmacological induction in cells under pathological stress make these proteins an attractive therapeutic target for various neurodegenerative diseases; these include Alzheimer's, Parkinson's, Huntington's, prion disease, and others. This review discusses the possible roles of HSPs, particularly HSP70 and small HSPs (alpha A and alpha B crystallins) in enhancing the survival of retinal ganglion cells (RGCs) in optic neuropathies such as glaucoma, which is characterized by progressive loss of vision caused by degeneration of RGCs and their axons in the optic nerve. Studies in animal models of RGC degeneration induced by ocular hypertension, optic nerve crush and axotomy show that upregulation of HSP70 expression by hyperthermia, zinc, geranyl-geranyl acetone, 17-AAG (a HSP90 inhibitor), or through transfection of retinal cells with AAV2-HSP70 effectively supports the survival of injured RGCs. RGCs survival was also stimulated by overexpression of alpha A and alpha B crystallins. These findings provide support for translating the HSP70- and alpha crystallin-based cell survival strategy into therapy to protect and rescue injured RGCs from degeneration associated with glaucomatous and other optic neuropathies.
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Affiliation(s)
- Natik Piri
- Stein Eye Institute, University of California, Los Angeles, CA 90095, USA; Brain Research Institute, University of California, Los Angeles, CA 90095, USA.
| | - Jacky M K Kwong
- Stein Eye Institute, University of California, Los Angeles, CA 90095, USA
| | - Lei Gu
- Stein Eye Institute, University of California, Los Angeles, CA 90095, USA
| | - Joseph Caprioli
- Stein Eye Institute, University of California, Los Angeles, CA 90095, USA; Brain Research Institute, University of California, Los Angeles, CA 90095, USA
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91
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Abstract
αB-crystallin is a widely expressed member of the small heat shock protein family that protects cells from stress by its dual function as a molecular chaperone to preserve proteostasis and as a cell death antagonist that negatively regulates components of the conserved apoptotic cell death machinery. Deregulated expression of αB-crystallin occurs in a broad array of solid tumors and has been linked to tumor progression and poor clinical outcomes. This review will focus on new insights into the molecular mechanisms by which oncogenes, oxidative stress, matrix detachment and other tumor microenvironmental stressors deregulate αB-crystallin expression. We will also review accumulating evidence pointing to an essential role for αB-crystallin in the multi-step metastatic cascade whereby tumor cells colonize distant organs by circumventing a multitude of barriers to cell migration and survival. Finally, we will evaluate emerging strategies to therapeutically target αB-crystallin and/or interacting proteins to selectively activate apoptosis and/or derail the metastatic cascade in an effort to improve outcomes for patients with metastatic disease.
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92
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Small Heat Shock Proteins, a Key Player in Grass Plant Thermotolerance. HEAT SHOCK PROTEINS AND PLANTS 2016. [DOI: 10.1007/978-3-319-46340-7_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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93
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Jovcevski B, Kelly MA, Rote AP, Berg T, Gastall HY, Benesch JLP, Aquilina JA, Ecroyd H. Phosphomimics destabilize Hsp27 oligomeric assemblies and enhance chaperone activity. ACTA ACUST UNITED AC 2015; 22:186-95. [PMID: 25699602 DOI: 10.1016/j.chembiol.2015.01.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 01/07/2015] [Accepted: 01/21/2015] [Indexed: 01/06/2023]
Abstract
Serine phosphorylation of the mammalian small heat-shock protein Hsp27 at residues 15, 78, and 82 is thought to regulate its structure and chaperone function; however, the site-specific impact has not been established. We used mass spectrometry to assess the combinatorial effect of mutations that mimic phosphorylation upon the oligomeric state of Hsp27. Comprehensive dimerization yielded a relatively uncrowded spectrum, composed solely of even-sized oligomers. Modification at one or two serines decreased the average oligomeric size, while the triple mutant was predominantly a dimer. These changes were reflected in a greater propensity for oligomers to dissociate upon increased modification. The ability of Hsp27 to prevent amorphous or fibrillar aggregation of target proteins was enhanced and correlated with the amount of dissociated species present. We propose that, in vivo, phosphorylation promotes oligomer dissociation, thereby enhancing chaperone activity. Our data support a model in which dimers are the chaperone-active component of Hsp27.
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Affiliation(s)
- Blagojce Jovcevski
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Megan A Kelly
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Anthea P Rote
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Tracey Berg
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Heidi Y Gastall
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, South Parks Road, Oxford OX1 3QZ, UK
| | - Justin L P Benesch
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, South Parks Road, Oxford OX1 3QZ, UK
| | - J Andrew Aquilina
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Heath Ecroyd
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia.
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94
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Thornell E, Aquilina A. Regulation of αA- and αB-crystallins via phosphorylation in cellular homeostasis. Cell Mol Life Sci 2015; 72:4127-37. [PMID: 26210153 PMCID: PMC11113999 DOI: 10.1007/s00018-015-1996-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 07/10/2015] [Accepted: 07/16/2015] [Indexed: 11/27/2022]
Abstract
αA-Crystallin (αA) and αB-crystallin (αB) are small heat shock proteins responsible for the maintenance of transparency in the lens. In non-lenticular tissues, αB is involved in both maintenance of the cytoskeleton and suppression of neurodegeneration amongst other roles. Despite their importance in maintaining cellular health, modifications and mutations to αA and αB appear to play a role in disease states such as cataract and myopathies. The list of modifications that have been reported is extensive and include oxidation, disulphide bond formation, C- and N-terminal truncation, acetylation, carboxymethylation, carboxyethylation, carbamylation, deamidation, phosphorylation and methylation. Such modifications, notably phosphorylation, are alleged to cause changes to chaperone activity by inducing substructural changes and altering subunit exchange dynamics. Although the effect modification has on the activities of αA and αB is contentious, it has been proposed that these changes are responsible for the induction of hyperactivity and are thereby indirectly responsible for protein deposition characteristic of many diseases associated with αA and αB. This review compiles all reported sites of αA and αB modifications, and investigates the role phosphorylation, in particular, plays in cellular processes.
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Affiliation(s)
- Erin Thornell
- Illawarra Health and Medical Research Institute, University of Wollongong, Northfields Ave., Wollongong, NSW, 2522, Australia.
| | - Andrew Aquilina
- Illawarra Health and Medical Research Institute, University of Wollongong, Northfields Ave., Wollongong, NSW, 2522, Australia
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95
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The chaperone αB-crystallin uses different interfaces to capture an amorphous and an amyloid client. Nat Struct Mol Biol 2015; 22:898-905. [PMID: 26458046 DOI: 10.1038/nsmb.3108] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 09/11/2015] [Indexed: 12/20/2022]
Abstract
Small heat-shock proteins, including αB-crystallin (αB), play an important part in protein homeostasis, because their ATP-independent chaperone activity inhibits uncontrolled protein aggregation. Mechanistic details of human αB, particularly in its client-bound state, have been elusive so far, owing to the high molecular weight and the heterogeneity of these complexes. Here we provide structural insights into this highly dynamic assembly and show, by using state-of-the-art NMR spectroscopy, that the αB complex is assembled from asymmetric building blocks. Interaction studies demonstrated that the fibril-forming Alzheimer's disease Aβ1-40 peptide preferentially binds to a hydrophobic edge of the central β-sandwich of αB. In contrast, the amorphously aggregating client lysozyme is captured by the partially disordered N-terminal domain of αB. We suggest that αB uses its inherent structural plasticity to expose distinct binding interfaces and thus interact with a wide range of structurally variable clients.
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96
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Wright MA, Aprile FA, Arosio P, Vendruscolo M, Dobson CM, Knowles TPJ. Biophysical approaches for the study of interactions between molecular chaperones and protein aggregates. Chem Commun (Camb) 2015; 51:14425-34. [PMID: 26328629 PMCID: PMC8597951 DOI: 10.1039/c5cc03689e] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 08/07/2015] [Indexed: 12/25/2022]
Abstract
Molecular chaperones are key components of the arsenal of cellular defence mechanisms active against protein aggregation. In addition to their established role in assisting protein folding, increasing evidence indicates that molecular chaperones are able to protect against a range of potentially damaging aspects of protein behaviour, including misfolding and aggregation events that can result in the generation of aberrant protein assemblies whose formation is implicated in the onset and progression of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. The interactions between molecular chaperones and different amyloidogenic protein species are difficult to study owing to the inherent heterogeneity of the aggregation process as well as the dynamic nature of molecular chaperones under physiological conditions. As a consequence, understanding the detailed microscopic mechanisms underlying the nature and means of inhibition of aggregate formation remains challenging yet is a key objective for protein biophysics. In this review, we discuss recent results from biophysical studies on the interactions between molecular chaperones and protein aggregates. In particular, we focus on the insights gained from current experimental techniques into the dynamics of the oligomerisation process of molecular chaperones, and highlight the opportunities that future biophysical approaches have in advancing our understanding of the great variety of biological functions of this important class of proteins.
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Affiliation(s)
- Maya A. Wright
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
| | - Francesco A. Aprile
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
| | - Paolo Arosio
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
| | - Michele Vendruscolo
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
| | - Christopher M. Dobson
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
| | - Tuomas P. J. Knowles
- Department of Chemistry, University of CambridgeLensfield RoadCambridge CB2 1EWUK+44 (0)1223 336300
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97
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Rajagopal P, Liu Y, Shi L, Clouser AF, Klevit RE. Structure of the α-crystallin domain from the redox-sensitive chaperone, HSPB1. JOURNAL OF BIOMOLECULAR NMR 2015; 63:223-8. [PMID: 26243512 PMCID: PMC4589510 DOI: 10.1007/s10858-015-9973-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 07/27/2015] [Indexed: 05/27/2023]
Abstract
Small heat shock proteins (sHSP) are a class of ATP-independent protein chaperones found throughout nature. They share a common ability to maintain partly unfolded proteins in soluble states under cellular stress conditions. All sHSPs contain a central domain called the α-crystallin domain (ACD); the domain is found in all sHSPs and in no other proteins and therefore defines the family. Though most sHSPs form large, often polydisperse oligomers from varying numbers of subunits, the ACD is both necessary and sufficient for formation of a dimer, the fundamental building block for oligomers. HSPB1 (also known as Hsp27) is unique among the ten human sHSPs because it contains a Cys residue in its dimer interface. HSPB1 is highly expressed under conditions of oxidative stress and is proposed to serve as a redox-sensitive chaperone. HSPB1 residue Cys137 has been proposed to modulate function by existing in either its oxidized (disulfide) or reduced (thiol) form (Chalova et al 2014). Here we report the solution-state NMR structure of oxidized HSPB1-ACD and compare it to a previously determined crystal structure of the reduced state. Formation of the disulfide-bond across the dimer interface yields a locked dimer structure with increased accessible hydrophobic surface. In the context of full-length HSPB1 oligomers, oxidation of Cys137 is associated with enhanced ability to bind the hydrophobic dye, 8-Anilinonapthalene-1-sulfonic-acid, implying an increased ability to interact with client proteins under oxidative stress.
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Affiliation(s)
- Ponni Rajagopal
- Department of Biochemistry, University of Washington, Seattle, WA, 98195-7350, USA
| | - Ying Liu
- Department of Biochemistry, University of Washington, Seattle, WA, 98195-7350, USA
| | - Lei Shi
- Department of Biochemistry, University of Washington, Seattle, WA, 98195-7350, USA
| | - Amanda F Clouser
- Department of Biochemistry, University of Washington, Seattle, WA, 98195-7350, USA
| | - Rachel E Klevit
- Department of Biochemistry, University of Washington, Seattle, WA, 98195-7350, USA.
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98
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Bakthisaran R, Akula KK, Tangirala R, Rao CM. Phosphorylation of αB-crystallin: Role in stress, aging and patho-physiological conditions. Biochim Biophys Acta Gen Subj 2015; 1860:167-82. [PMID: 26415747 DOI: 10.1016/j.bbagen.2015.09.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 09/22/2015] [Accepted: 09/23/2015] [Indexed: 01/18/2023]
Abstract
BACKGROUND αB-crystallin, once thought to be a lenticular protein, is ubiquitous and has critical roles in several cellular processes that are modulated by phosphorylation. Serine residues 19, 45 and 59 of αB-crystallin undergo phosphorylation. Phosphorylation of S45 is mediated by p44/42 MAP kinase, whereas S59 phosphorylation is mediated by MAPKAP kinase-2. Pathway involved in S19 phosphorylation is not known. SCOPE OF REVIEW The review highlights the role of phosphorylation in (i) oligomeric structure, stability and chaperone activity, (ii) cellular processes such as apoptosis, myogenic differentiation, cell cycle regulation and angiogenesis, and (iii) aging, stress, cardiomyopathy-causing αB-crystallin mutants, and in other diseases. MAJOR CONCLUSIONS Depending on the context and extent of phosphorylation, αB-crystallin seems to confer beneficial or deleterious effects. Phosphorylation alters structure, stability, size distribution and dynamics of the oligomeric assembly, thus modulating chaperone activity and various cellular processes. Phosphorylated αB-crystallin has a tendency to partition to the cytoskeleton and hence to the insoluble fraction. Low levels of phosphorylation appear to be protective, while hyperphosphorylation has negative implications. Mutations in αB-crystallin, such as R120G, Q151X and 464delCT, associated with inherited myofibrillar myopathy lead to hyperphosphorylation and intracellular inclusions. An ongoing study in our laboratory with phosphorylation-mimicking mutants indicates that phosphorylation of R120GαB-crystallin increases its propensity to aggregate. GENERAL SIGNIFICANCE Phosphorylation of αB-crystallin has dual role that manifests either beneficial or deleterious consequences depending on the extent of phosphorylation and interaction with cytoskeleton. Considering that disease-causing mutants of αB-crystallin are hyperphosphorylated, moderation of phosphorylation may be a useful strategy in disease management. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease.
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Affiliation(s)
- Raman Bakthisaran
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Kranthi Kiran Akula
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Ramakrishna Tangirala
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India
| | - Ch Mohan Rao
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India.
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99
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Koteiche HA, Claxton DP, Mishra S, Stein RA, McDonald ET, Mchaourab HS. Species-Specific Structural and Functional Divergence of α-Crystallins: Zebrafish αBa- and Rodent αA(ins)-Crystallin Encode Activated Chaperones. Biochemistry 2015; 54:5949-58. [PMID: 26378715 DOI: 10.1021/acs.biochem.5b00678] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In addition to contributing to lens optical properties, the α-crystallins are small heat shock proteins that possess chaperone activity and are predicted to bind and sequester destabilized proteins to delay cataract formation. The current model of α-crystallin chaperone mechanism envisions a transition from the native oligomer to an activated form that has higher affinity to non-native states of the substrate. Previous studies have suggested that this oligomeric plasticity is encoded in the primary sequence and controls access to high affinity binding sites within the N-terminal domain. Here, we further examined the role of sequence variation in the context of species-specific α-crystallins from rat and zebrafish. Alternative splicing of the αA gene in rodents produces αA(ins), which is distinguished by a longer N-terminal domain. The zebrafish genome includes duplicate αB-crystallin genes, αBa and αBb, which display divergent primary sequence and tissue expression patterns. Equilibrium binding experiments were employed to quantitatively define chaperone interactions with a destabilized model substrate, T4 lysozyme. In combination with multiangle light scattering, we show that rat αA(ins) and zebrafish α-crystallins display distinct global structural properties and chaperone activities. Notably, we find that αA(ins) and αBa demonstrate substantially enhanced chaperone function relative to other α-crystallins, binding the same substrate more than 2 orders of magnitude higher affinity and mimicking the activity of fully activated mammalian small heat shock proteins. These results emphasize the role of sequence divergence as an evolutionary strategy to tune chaperone function to the requirements of the tissues and organisms in which they are expressed.
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Affiliation(s)
- Hanane A Koteiche
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
| | - Derek P Claxton
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
| | - Sanjay Mishra
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
| | - Richard A Stein
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
| | - Ezelle T McDonald
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
| | - Hassane S Mchaourab
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States
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100
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Clark JI. Functional sequences in human alphaB crystallin. Biochim Biophys Acta Gen Subj 2015; 1860:240-5. [PMID: 26341790 DOI: 10.1016/j.bbagen.2015.08.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/20/2015] [Accepted: 08/24/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND Human alphaB crystallin (HspB5) contains the alpha crystallin core domain, a series of antiparallel beta-strands organized into the characteristic beta sandwich of small heat shock proteins (sHsps). The full 3-dimensional structure for alpha crystallin has not been determined and the mechanism for the biological activity remains elusive because sHsps participate in multiple interactions with a broad range of target proteins that favor self-assembly of polydisperse fibrils and complexes. We selected human alphaB crystallin to study interactive sequences because it is involved in many human condensation, amyloid, and aggregation diseases and it is very sensitive to the destabilization of unfolding proteins. Sophisticated methods are being used to analyze and complete the structure of alphaB crystallin with the expectation of understanding sHsp function. This review considers the identification of interactive sites on the surface of the alphaB crystallin, which may be the key to understanding the multifunctional activity of human alphaB crystallin. SCOPE OF REVIEW This review summarizes the research on the identification of the bioactive interactive sequences responsible for the function of human alphaB crystallin, an sHsp with chaperone-like activity. MAJOR CONCLUSIONS The multifunctional activity of human alphaB crystallin results from the interactive peptide sequences exposed on the surface of the molecule. The multiple, non-covalent, interactive sequences can account for the selectivity and sensitivity of alphaB crystallin to the initiation of protein unfolding. GENERAL SIGNIFICANCE Human alphaB crystallin may be an important part of an endogenous protective mechanism in aging cells and tissues. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease.
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Affiliation(s)
- John I Clark
- Departments of Biological Structure and Ophthalmology, University of Washington, Seattle, WA 98195-7420, USA.
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