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Proteomic analysis of rabbit fresh and cryopreserved semen provides an important insight into molecular mechanisms of cryoinjuries to spermatozoa. Theriogenology 2022; 191:77-95. [DOI: 10.1016/j.theriogenology.2022.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 07/12/2022] [Accepted: 07/25/2022] [Indexed: 11/20/2022]
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Wilson MR, Satapathy S, Jeong S, Fini ME. Clusterin, other extracellular chaperones, and eye disease. Prog Retin Eye Res 2022; 89:101032. [PMID: 34896599 PMCID: PMC9184305 DOI: 10.1016/j.preteyeres.2021.101032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 11/30/2021] [Accepted: 11/30/2021] [Indexed: 12/15/2022]
Abstract
Proteostasis refers to all the processes that maintain the correct expression level, location, folding and turnover of proteins, essential to organismal survival. Both inside cells and in body fluids, molecular chaperones play key roles in maintaining proteostasis. In this article, we focus on clusterin, the first-recognized extracellular mammalian chaperone, and its role in diseases of the eye. Clusterin binds to and inhibits the aggregation of proteins that are misfolded due to mutations or stresses, clears these aggregating proteins from extracellular spaces, and facilitates their degradation. Clusterin exhibits three main homeostatic activities: proteostasis, cytoprotection, and anti-inflammation. The so-called "protein misfolding diseases" are caused by aggregation of misfolded proteins that accumulate pathologically as deposits in tissues; we discuss several such diseases that occur in the eye. Clusterin is typically found in these deposits, which is interpreted to mean that its capacity as a molecular chaperone to maintain proteostasis is overwhelmed in the disease state. Nevertheless, the role of clusterin in diseases involving such deposits needs to be better defined before therapeutic approaches can be entertained. A more straightforward case can be made for therapeutic use of clusterin based on its proteostatic role as a proteinase inhibitor, as well as its cytoprotective and anti-inflammatory properties. It is likely that clusterin works together in this way with other extracellular chaperones to protect the eye from disease, and we discuss several examples. We end this article by predicting future steps that may lead to development of clusterin as a biological drug.
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Affiliation(s)
- Mark R Wilson
- Molecular Horizons and the School of Chemistry and Molecular Bioscience, University of Wollongong; Illawarra Health and Medical Research Institute, Northfields Avenue, Wollongong, New South Wales, 2522, Australia.
| | - Sandeep Satapathy
- Molecular Horizons and the School of Chemistry and Molecular Bioscience, University of Wollongong; Illawarra Health and Medical Research Institute, Northfields Avenue, Wollongong, New South Wales, 2522, Australia.
| | - Shinwu Jeong
- USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, 1333 San Pablo Street., Los Angeles, CA, 90033, USA.
| | - M Elizabeth Fini
- New England Eye Center, Tufts Medical Center and Department of Ophthalmology, Tufts University School of Medicine; Program in Pharmacology & Drug Development, Graduate School of Biomedical Sciences, Tufts University, 800 Washington St, Boston, MA, 02111, USA.
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Menezes TDA, Bustamante-Filho IC, Paschoal AFL, Dalberto PF, Bizarro CV, Bernardi ML, Ulguim RDR, Bortolozzo FP, Mellagi APG. Differential seminal plasma proteome signatures of boars with high and low resistance to hypothermic semen preservation at 5°C. Andrology 2021; 8:1907-1922. [PMID: 33460278 DOI: 10.1111/andr.12869] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/20/2020] [Accepted: 07/15/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND Hypothermic storage at 5°C has been investigated as an alternative to promote the prudent use of antibiotics for boar artificial insemination doses. However, this temperature is challenging for some ejaculates or boars. OBJECTIVE The present study aimed to identify putative biomarkers for semen resistance to hypothermic storage at 5°C by comparing the seminal plasma proteomes of boars with high and low seminal resistance to preservation at 5°C. MATERIALS AND METHODS From an initial group of 34 boars, 15 were selected based on the following criteria: ejaculate with ≤20% abnormal spermatozoa and at least 70% progressive motility at 120 hours of storage at 17°C. Then, based on the response to semen hypothermic storage at 5°C, boars were classified into two categories: high resistance-progressive motility of >75% in the three collections (n = 3); and low resistance-progressive motility of <75% in the three collections (n = 3). Seminal plasma proteins were analyzed in pools, and differential proteomics was performed using Multidimensional Protein Identification Technology. RESULTS Progressive motility was lower at 120 hours of storage in low resistance, compared to high resistance boars (P < .05). Acrosome and plasma membrane integrity were not affected by the boar category, storage time, or their interaction (P ≥ .104). Sixty-five proteins were considered for differential proteomics. Among the differentially expressed and exclusive proteins, the identification of proteins such cathepsin B, legumain, and cystatin B suggests significant changes in key enzymes (eg, metalloproteinases) involved in spermatogenesis, sperm integrity, and fertilizing potential. DISCUSSION AND CONCLUSION Differences in the seminal plasma suggest that proteins involved in the proteolytic activation of metalloproteinases and proteins related to immune response modulation could disrupt key cellular pathways during spermatogenesis and epididymal maturation, resulting in altered resistance to chilling injury. Further in vivo studies focusing on the immunological crosstalk between epithelial cells and gametes might explain how the immune regulators influence sperm resistance to hipothermic storage.
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Affiliation(s)
- Tila de Alcantara Menezes
- Setor de Suínos, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | | | - Pedro Ferrari Dalberto
- Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ciência e Tecnologia em Tuberculose, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.,Programa de Pós-Graduação em Biologia Celular e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - Cristiano Valim Bizarro
- Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ciência e Tecnologia em Tuberculose, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.,Programa de Pós-Graduação em Biologia Celular e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
| | - Mari Lourdes Bernardi
- Departamento de Zootecnia, Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Rafael da Rosa Ulguim
- Setor de Suínos, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Ozawa D, Nomura R, Mangione PP, Hasegawa K, Okoshi T, Porcari R, Bellotti V, Naiki H. Multifaceted anti-amyloidogenic and pro-amyloidogenic effects of C-reactive protein and serum amyloid P component in vitro. Sci Rep 2016; 6:29077. [PMID: 27380955 PMCID: PMC4933921 DOI: 10.1038/srep29077] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 06/10/2016] [Indexed: 01/07/2023] Open
Abstract
C-reactive protein (CRP) and serum amyloid P component (SAP), two major classical pentraxins in humans, are soluble pattern recognition molecules that regulate the innate immune system, but their chaperone activities remain poorly understood. Here, we examined their effects on the amyloid fibril formation from Alzheimer’s amyloid β (Aβ) (1-40) and on that from D76N β2-microglobulin (β2-m) which is related to hereditary systemic amyloidosis. CRP and SAP dose-dependently and substoichiometrically inhibited both Aβ(1-40) and D76N β2-m fibril formation in a Ca2+-independent manner. CRP and SAP interacted with fresh and aggregated Aβ(1-40) and D76N β2-m on the fibril-forming pathway. Interestingly, in the presence of Ca2+, SAP first inhibited, then significantly accelerated D76N β2-m fibril formation. Electron microscopically, the surface of the D76N β2-m fibril was coated with pentameric SAP. These data suggest that SAP first exhibits anti-amyloidogenic activity possibly via A face, followed by pro-amyloidogenic activity via B face, proposing a model that the pro- and anti-amyloidogenic activities of SAP are not mutually exclusive, but reflect two sides of the same coin, i.e., the B and A faces, respectively. Finally, SAP inhibits the heat-induced amorphous aggregation of human glutathione S-transferase. A possible role of pentraxins to maintain extracellular proteostasis is discussed.
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Affiliation(s)
- Daisaku Ozawa
- Life Science Unit, Tenure-Track Program for Innovative Research, University of Fukui, Fukui 910-1193, Japan
| | - Ryo Nomura
- Department of Molecular Pathology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - P Patrizia Mangione
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London NW3 2PF, UK
| | - Kazuhiro Hasegawa
- Department of Molecular Pathology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Tadakazu Okoshi
- Department of Molecular Pathology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Riccardo Porcari
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London NW3 2PF, UK
| | - Vittorio Bellotti
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London NW3 2PF, UK
| | - Hironobu Naiki
- Department of Molecular Pathology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
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Fukuda T, Miyake H, Enatsu N, Matsushita K, Fujisawa M. Seminal level of clusterin in infertile men as a significant biomarker reflecting spermatogenesis. Andrologia 2016; 48:1188-1194. [DOI: 10.1111/and.12558] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2016] [Indexed: 11/29/2022] Open
Affiliation(s)
- T. Fukuda
- Division of Urology; Kobe University Graduate School of Medicine; Kobe Japan
| | - H. Miyake
- Division of Urology; Kobe University Graduate School of Medicine; Kobe Japan
| | - N. Enatsu
- Division of Urology; Kobe University Graduate School of Medicine; Kobe Japan
| | - K. Matsushita
- Division of Urology; Kobe University Graduate School of Medicine; Kobe Japan
| | - M. Fujisawa
- Division of Urology; Kobe University Graduate School of Medicine; Kobe Japan
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Amyloid fibril formation by bovine α1-acid glycoprotein in a reducing environment: The role of disulfide bridges on the observed aggregation kinetics. Biochimie 2015; 118:244-52. [DOI: 10.1016/j.biochi.2015.09.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/22/2015] [Indexed: 11/18/2022]
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Kopecký V, Ettrich R, Pazderka T, Hofbauerová K, Řeha D, Baumruk V. Influence of ligand binding on structure and thermostability of human α1-acid glycoprotein. J Mol Recognit 2015; 29:70-9. [DOI: 10.1002/jmr.2496] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 08/05/2015] [Accepted: 08/05/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Vladimír Kopecký
- Institute of Physics, Faculty of Mathematics and Physics; Charles University in Prague; Ke Karlovu 5 CZ-12116 Prague 2 Czech Republic
| | - Rüdiger Ettrich
- Center for Nanobiology and Structural Biology, Institute of Microbiology; Academy of Sciences of the Czech Republic; Zámek 136 CZ-37333 Nové Hrady Czech Republic
- Faculty of Sciences; University of South Bohemia; Zámek 136 CZ-37333 Nové Hrady Czech Republic
| | - Tomáš Pazderka
- Institute of Physics, Faculty of Mathematics and Physics; Charles University in Prague; Ke Karlovu 5 CZ-12116 Prague 2 Czech Republic
| | - Kateřina Hofbauerová
- Institute of Physics, Faculty of Mathematics and Physics; Charles University in Prague; Ke Karlovu 5 CZ-12116 Prague 2 Czech Republic
- Institute of Microbiology; Academy of Sciences of the Czech Republic; Vídeňská 1083 CZ-142 20 Prague 4 Czech Republic
| | - David Řeha
- Center for Nanobiology and Structural Biology, Institute of Microbiology; Academy of Sciences of the Czech Republic; Zámek 136 CZ-37333 Nové Hrady Czech Republic
- Faculty of Sciences; University of South Bohemia; Zámek 136 CZ-37333 Nové Hrady Czech Republic
| | - Vladimír Baumruk
- Institute of Physics, Faculty of Mathematics and Physics; Charles University in Prague; Ke Karlovu 5 CZ-12116 Prague 2 Czech Republic
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Matsushita K, Miyake H, Chiba K, Fujisawa M. Clusterin produced by Sertoli cells inhibits heat stress-induced apoptosis in the rat testis. Andrologia 2015; 48:11-9. [PMID: 25661013 DOI: 10.1111/and.12404] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2014] [Indexed: 12/16/2022] Open
Abstract
The objectives of this study were to determine whether the inhibition of clusterin expression in rat Sertoli cells enhances heat stress-induced apoptosis. The scrotums of rats were immersed in a water bath of 43 °C for 15 min. Testicular weight and germ cell number markedly decreased after the heat treatment in a time-dependent manner. In contrast, clusterin mRNA and protein expression levels were significantly up-regulated and peaked on day 21. The apoptotic index was markedly increased 1 day after the heat treatment. We then purified Sertoli cells from the rat testes, and an expression vector containing siRNA targeting the clusterin gene was transiently transfected into Sertoli cells. Following exposure to heat stress at 41 °C for 12 h, clusterin mRNA was markedly up-regulated after transfection with the control vector; however, the transfection of siRNA targeting the clusterin resulted in >70% reduction in the expression of clusterin mRNA. Furthermore, the apoptotic index in these Sertoli cells was significantly higher after the treatment with siRNA targeting the clusterin than control, and the most prominent difference was observed within 24 h after the heat treatment. These results suggest that an increase in the secretion of clusterin by Sertoli cells protects the testes from heat stress-induced injury.
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Affiliation(s)
- K Matsushita
- Division of Urology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - H Miyake
- Division of Urology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - K Chiba
- Division of Urology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - M Fujisawa
- Division of Urology, Kobe University Graduate School of Medicine, Kobe, Japan
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Affiliation(s)
- Amy R. Wyatt
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Justin J. Yerbury
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
| | - Heath Ecroyd
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
| | - Mark R. Wilson
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
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Wyatt AR, Wilson MR. Acute phase proteins are major clients for the chaperone action of α₂-macroglobulin in human plasma. Cell Stress Chaperones 2013; 18:161-70. [PMID: 22896034 PMCID: PMC3581619 DOI: 10.1007/s12192-012-0365-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 07/25/2012] [Accepted: 07/26/2012] [Indexed: 11/30/2022] Open
Abstract
Extracellular protein misfolding is implicated in many age-related diseases including Alzheimer's disease, macular degeneration and arthritis. In this study, putative endogenous clients for the chaperone activity of α₂-macroglobulin (α₂M) were identified after human plasma was subjected to physiologically relevant sheer stress at 37 °C for 10 days. Western blot analysis showed that four major acute phase proteins: ceruloplasmin, fibrinogen, α₁-acid glycoprotein and complement component 3, preferentially co-purified with α₂M after plasma was stressed. Furthermore, the formation of complexes between α₂M and these putative chaperone clients, detected by sandwich ELISA, was shown to be enhanced in response to stress. These results support the hypothesis that α₂M plays an important role in extracellular proteostasis by sequestering misfolded proteins and targeting them for disposal, particularly during acute phase reactions.
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Affiliation(s)
- Amy R. Wyatt
- />Department of Chemistry, University of Cambridge, Cambridge, UK
- />Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW Australia
| | - Mark R. Wilson
- />Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW Australia
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Scirè A, Baldassarre M, Galeazzi R, Tanfani F. Fibrillation properties of human α₁-acid glycoprotein. Biochimie 2012; 95:158-66. [PMID: 22996070 DOI: 10.1016/j.biochi.2012.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 09/07/2012] [Indexed: 10/27/2022]
Abstract
Human α(1)-acid glycoprotein (AGP) is a positive acute phase plasma protein containing two disulfide bridges. Structural studies have shown that under specific conditions AGP undergoes aggregation. In this study, we analysed the nature of AGP's aggregates formed under reducing and non-reducing conditions at pH 5.5 and at relatively low temperatures. Thioflavin T and Congo red spectroscopic analyses indicated the presence of cross-β structures in both unreduced and reduced AGP aggregates. In these samples amyloid-like fibrils were detected by transmission electron microscopy. The fibrils are branched and bent and present in very large amount in reduced AGP. Kinetics of AGP fibrillation proceeds without a lag phase and the rate constants of cross-β formation are linearly dependent on AGP concentration and result higher under reducing conditions. The data suggest a possible downhill mechanism of polymerization with a first-order monomer concentration dependence. Bioinformatics tools highlighted an extended region that sheathes one side of the molecule containing aggregation-prone regions. Reducing conditions make the extended region less constricted, allowing greater exposure of aggregation-prone regions, thus explaining the higher propensity of AGP to aggregate and fibrillate.
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Affiliation(s)
- Andrea Scirè
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Ranieri, 60131 Ancona, Italy
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12
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Acute phase proteins in ruminants. J Proteomics 2012; 75:4207-31. [DOI: 10.1016/j.jprot.2012.04.004] [Citation(s) in RCA: 307] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 03/29/2012] [Accepted: 04/02/2012] [Indexed: 01/03/2023]
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Gianazza E, Wait R, Eberini I, Sensi C, Sironi L, Miller I. Proteomics of rat biological fluids — The tenth anniversary update. J Proteomics 2012; 75:3113-28. [DOI: 10.1016/j.jprot.2012.03.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Revised: 03/26/2012] [Accepted: 03/28/2012] [Indexed: 01/29/2023]
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Scirè A, Baldassarre M, Lupidi G, Tanfani F. Importance of pH and disulfide bridges on the structural and binding properties of human α₁-acid glycoprotein. Biochimie 2011; 93:1529-36. [PMID: 21621584 DOI: 10.1016/j.biochi.2011.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 05/10/2011] [Indexed: 11/16/2022]
Abstract
Human α(1)-acid glycoprotein (AGP) is an acute phase plasma glycoprotein containing two disulfide bridges. As a member of the lipocalin superfamily, it binds and transports several basic and neutral ligands, but a number of other activities have also been described. Thanks to its binding properties, AGP is also a good candidate for the development of biosensors and affinity chromatography media, and in this context detailed structural information is needed. The structural properties of AGP at different p(2)Hs and under reducing conditions were analysed by FT-IR spectroscopy. The obtained data indicate that AGP, when denatured, does not aggregate at neutral or basic p(2)Hs whilst it does at acidic p(2)Hs. Under reducing conditions the protein is remarkably less thermostable than its oxidized counterpart and presents an enhanced tendency to aggregate, even at neutral p(2)H. A heat-induced molten globule-like state (MG) was detected at 55 °C at p(2)H 7.4 and 5.5. At p(2)H 4.5 the MG occurred at 45 °C with an onset of formation at 40 °C. The MG was not observed under reducing conditions. A lower affinity of chlorpromazine and progesterone for the MG formed at p(2)H 4.5 and 40 °C was observed, suggesting that ligand(s) may be released near the negative surfaces of biological membranes. Furthermore, the reduced AGP displays an enhanced affinity for progesterone, indicating the importance of disulfide bonds for the binding capacity of AGP.
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Affiliation(s)
- Andrea Scirè
- Dipartimento di Biochimica Biologia e Genetica, Università Politecnica delle Marche, Ancona, Italy
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Dabbs RA, Wyatt AR, Yerbury JJ, Ecroyd H, Wilson MR. Extracellular Chaperones. Top Curr Chem (Cham) 2010. [PMID: 21516385 DOI: 10.1007/128_2010_85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The maintenance of the levels and correct folding state of proteins (proteostasis) is a fundamental prerequisite for life. Life has evolved complex mechanisms to maintain proteostasis and many of these that operate inside cells are now well understood. The same cannot yet be said of corresponding processes in extracellular fluids of the human body, where inappropriate protein aggregation is known to underpin many serious diseases such as Alzheimer's disease, type II diabetes and prion diseases. Recent research has uncovered a growing family of abundant extracellular chaperones in body fluids which appear to selectively bind to exposed regions of hydrophobicity on misfolded proteins to inhibit their toxicity and prevent them from aggregating to form insoluble deposits. These extracellular chaperones are also implicated in clearing the soluble, stabilized misfolded proteins from body fluids via receptor-mediated endocytosis for subsequent lysosomal degradation. Recent work also raises the possibility that extracellular chaperones may play roles in modulating the immune response. Future work will better define the in vivo functions of extracellular chaperones in proteostasis and immunology and pave the way for the development of new treatments for serious diseases.
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Zsila F. Inhibition of heat- and chemical-induced aggregation of various proteins reveals chaperone-like activity of the acute-phase component and serine protease inhibitor human alpha(1)-antitrypsin. Biochem Biophys Res Commun 2010; 393:242-7. [PMID: 20117085 DOI: 10.1016/j.bbrc.2010.01.110] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Accepted: 01/27/2010] [Indexed: 10/19/2022]
Abstract
In vitro chaperone-like activity of the serpin family member and plasma acute-phase component human alpha(1)-antitrypsin (AAT) has been shown for the first time. Results of light-scattering experiments demonstrated that AAT efficiently inhibits both heat- and chemical-induced aggregation of various test proteins including alcohol dehydrogenase, aldolase, carbonic anhydrase, catalase, citrate synthase, enolase, glutathione S-transferase, l-lactate dehydrogenase, and beta(L)-crystallin. The results suggest that the unique metastable serpin architecture enables dual function, protease inhibiton as well as chaperone activity and highlight the serpin superfamily as a possible source of additional intra- and extracellular chaperones (e.g. alpha(1)-antichymotrypsin). The present finding is surprising in the light of the well-known role of mutated forms of AAT and other serpins in the pathogenesis of diseases called serpinopathies that featured with aberrant conformational transitions and consequent self-aggregation of serpin proteins.
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Affiliation(s)
- Ferenc Zsila
- Department of Molecular Pharmacology, Institute of Biomolecular Chemistry, Chemical Research Center, Budapest, Pusztaszeri út, Hungary.
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