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Palihati N, Tang Y, Yin Y, Yu D, Liu G, Quan Z, Ni J, Yan Y, Qing H. Clusterin is a Potential Therapeutic Target in Alzheimer's Disease. Mol Neurobiol 2024; 61:3836-3850. [PMID: 38017342 DOI: 10.1007/s12035-023-03801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 11/10/2023] [Indexed: 11/30/2023]
Abstract
In recent years, Clusterin, a glycosylated protein with multiple biological functions, has attracted extensive research attention. It is closely associated with the physiological and pathological states within the organism. Particularly in Alzheimer's disease (AD) research, Clusterin plays a significant role in the disease's occurrence and progression. Numerous studies have demonstrated a close association between Clusterin and AD. Firstly, the expression level of Clusterin in the brain tissue of AD patients is closely related to pathological progression. Secondly, Clusterin is involved in the deposition and formation of β-amyloid, which is a crucial process in AD development. Furthermore, Clusterin may affect the pathogenesis of AD through mechanisms such as regulating inflammation, controlling cell apoptosis, and clearing pathological proteins. Therefore, further research on the relationship between Clusterin and AD will contribute to a deeper understanding of the etiology of this neurodegenerative disease and provide a theoretical basis for developing early diagnostic and therapeutic strategies for AD. This also makes Clusterin one of the research focuses as a potential biomarker for AD diagnosis and treatment monitoring.
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Affiliation(s)
- Nazhakaiti Palihati
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Yuanhong Tang
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Yajuan Yin
- Department of Cardiology, The First Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China
| | - Ding Yu
- Department of Cardiology, The First Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China
| | - Gang Liu
- Department of Cardiology, The First Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China
| | - Zhenzhen Quan
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Junjun Ni
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Yan Yan
- Department of Cardiology, The First Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China.
| | - Hong Qing
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen, 518172, China.
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Gross C, Guérin LP, Socol BG, Germain L, Guérin SL. The Ins and Outs of Clusterin: Its Role in Cancer, Eye Diseases and Wound Healing. Int J Mol Sci 2023; 24:13182. [PMID: 37685987 PMCID: PMC10488069 DOI: 10.3390/ijms241713182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/17/2023] [Accepted: 08/21/2023] [Indexed: 09/10/2023] Open
Abstract
Clusterin (CLU) is a glycoprotein originally discovered in 1983 in ram testis fluid. Rapidly observed in other tissues, it was initially given various names based on its function in different tissues. In 1992, it was finally named CLU by consensus. Nearly omnipresent in human tissues, CLU is strongly expressed at fluid-tissue interfaces, including in the eye and in particular the cornea. Recent research has identified different forms of CLU, with the most prominent being a 75-80 kDa heterodimeric protein that is secreted. Another truncated version of CLU (55 kDa) is localized to the nucleus and exerts pro-apoptotic activities. CLU has been reported to be involved in various physiological processes such as sperm maturation, lipid transportation, complement inhibition and chaperone activity. CLU was also reported to exert important functions in tissue remodeling, cell-cell adhesion, cell-substratum interaction, cytoprotection, apoptotic cell death, cell proliferation and migration. Hence, this protein is sparking interest in tissue wound healing. Moreover, CLU gene expression is finely regulated by cytokines, growth factors and stress-inducing agents, leading to abnormally elevated levels of CLU in many states of cellular disturbance, including cancer and neurodegenerative conditions. In the eye, CLU expression has been reported as being severely increased in several pathologies, such as age-related macular degeneration and Fuch's corneal dystrophy, while it is depleted in others, such as pathologic keratinization. Nevertheless, the precise role of CLU in the development of ocular pathologies has yet to be deciphered. The question of whether CLU expression is influenced by these disorders or contributes to them remains open. In this article, we review the actual knowledge about CLU at both the protein and gene expression level in wound healing, and explore the possibility that CLU is a key factor in cancer and eye diseases. Understanding the expression and regulation of CLU could lead to the development of novel therapeutics for promoting wound healing.
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Affiliation(s)
- Christelle Gross
- Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX, Québec City, QC G1V 0A6, Canada; (C.G.); (B.G.S.); (L.G.)
- Centre de Recherche du CHU de Québec, Axe Médecine Régénératrice, Québec City, QC G1J 1Z4, Canada
- Département d’Ophtalmologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
| | | | - Bianca G. Socol
- Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX, Québec City, QC G1V 0A6, Canada; (C.G.); (B.G.S.); (L.G.)
| | - Lucie Germain
- Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX, Québec City, QC G1V 0A6, Canada; (C.G.); (B.G.S.); (L.G.)
- Centre de Recherche du CHU de Québec, Axe Médecine Régénératrice, Québec City, QC G1J 1Z4, Canada
- Département d’Ophtalmologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
- Département de Chirurgie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Sylvain L. Guérin
- Centre de Recherche en Organogénèse Expérimentale de l’Université Laval/LOEX, Québec City, QC G1V 0A6, Canada; (C.G.); (B.G.S.); (L.G.)
- Centre de Recherche du CHU de Québec, Axe Médecine Régénératrice, Québec City, QC G1J 1Z4, Canada
- Département d’Ophtalmologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
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Kovács P, Pushparaj PN, Takács R, Mobasheri A, Matta C. The clusterin connectome: Emerging players in chondrocyte biology and putative exploratory biomarkers of osteoarthritis. Front Immunol 2023; 14:1103097. [PMID: 37033956 PMCID: PMC10081159 DOI: 10.3389/fimmu.2023.1103097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 02/23/2023] [Indexed: 03/17/2023] Open
Abstract
IntroductionClusterin is amoonlighting protein that hasmany functions. It is amultifunctional Q6 holdase chaperone glycoprotein that is present intracellularly and extracellularly in almost all bodily fluids. Clusterin is involved in lipid transport, cell differentiation, regulation of apoptosis, and clearance of cellular debris, and plays a protective role in ensuring cellular survival. However, the possible involvement of clusterin in arthritic disease remains unclear. Given the significant potential of clusterin as a biomarker of osteoarthritis (OA), a more detailed analysis of its complex network in an inflammatory environment, specifically in the context of OA, is required. Based on the molecular network of clusterin, this study aimed to identify interacting partners that could be developed into biomarker panels for OA.MethodsThe STRING database and Cytoscape were used to map and visualize the clusterin connectome. The Qiagen Ingenuity Pathway Analysis (IPA) software was used to analyze and study clusterinassociated signaling networks in OA. We also analyzed transcription factors known to modulate clusterin expression, which may be altered in OA.ResultsThe top hits in the clusterin network were intracellular chaperones, aggregate-forming proteins, apoptosis regulators and complement proteins. Using a text-mining approach in Cytoscape, we identified additional interacting partners, including serum proteins, apolipoproteins, and heat shock proteins.DiscussionBased on known interactions with proteins, we predicted potential novel components of the clusterin connectome in OA, including selenoprotein R, semaphorins, and meprins, which may be important for designing new prognostic or diagnostic biomarker panels.
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Affiliation(s)
- Patrik Kovács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Peter Natesan Pushparaj
- Center of Excellence in Genomic Medicine Research (CEGMR), Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
- Center for Transdisciplinary Research, Department of Pharmacology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Chennai, India
| | - Roland Takács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Ali Mobasheri
- FibroHealth Interdisciplinary Research Programme, Fibrobesity Cluster, Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
- Department of Regenerative Medicine, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania
- Department of Joint Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
- World Health Organization Collaborating Center for Public Health Aspects of Musculoskeletal Health and Aging, Université de Liège, Liège, Belgium
- *Correspondence: Csaba Matta, ; Ali Mobasheri,
| | - Csaba Matta
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
- *Correspondence: Csaba Matta, ; Ali Mobasheri,
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Yuan Y, Zhu Q, Yao X, Shi Z, Wen J. Maternal circulating metabolic biomarkers and their prediction performance for gestational diabetes mellitus related macrosomia. BMC Pregnancy Childbirth 2023; 23:113. [PMID: 36788507 PMCID: PMC9926775 DOI: 10.1186/s12884-023-05440-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
INTRODUCTION Gestational diabetes mellitus (GDM), a metabolism-related pregnancy complication, is significantly associated with an increased risk of macrosomia. We hypothesized that maternal circulating metabolic biomarkers differed between women with GDM and macrosomia (GDM-M) and women with GDM and normal neonatal weight (GDM-N), and had good prediction performance for GDM-M. METHODS Plasma samples from 44 GDM-M and 44 GDM-N were analyzed using Olink Proseek multiplex metabolism assay targeting 92 biomarkers. Combined different clinical characteristics and Olink markers, LASSO regression was used to optimize variable selection, and Logistic regression was applied to build a predictive model. Nomogram was developed based on the selected variables visually. Receiver operating characteristic (ROC) curve, calibration plot, and clinical impact curve were used to validate the model. RESULTS We found 4 metabolism-related biomarkers differing between groups [CLUL1 (Clusterin-like protein 1), VCAN (Versican core protein), FCRL1 (Fc receptor-like protein 1), RNASE3 (Eosinophil cationic protein), FDR < 0.05]. Based on the different clinical characteristics and Olink markers, a total of nine predictors, namely pre-pregnancy body mass index (BMI), weight gain at 24 gestational weeks (gw), parity, oral glucose tolerance test (OGTT) 2 h glucose at 24 gw, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) at 24 gw, and plasma expression of CLUL1, VCAN and RNASE3 at 24 gw, were identified by LASSO regression. The model constructed using these 9 predictors displayed good prediction performance for GDM-M, with an area under the ROC of 0.970 (sensitivity = 0.955, specificity = 0.886), and was well calibrated (P Hosmer-Lemeshow test = 0.897). CONCLUSION The Model included pre-pregnancy BMI, weight gain at 24 gw, parity, OGTT 2 h glucose at 24 gw, HDL and LDL at 24 gw, and plasma expression of CLUL1, VCAN and RNASE3 at 24 gw had good prediction performance for predicting macrosomia in women with GDM.
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Affiliation(s)
- Yingdi Yuan
- grid.460072.7Department of Pediatrics, The First People’s Hospital of Lianyungang, Xuzhou Medical University Affiliated Hospital of Lianyungang (Lianyungang Clinical College of Nanjing Medical University), Lianyungang, China ,grid.459791.70000 0004 1757 7869Nanjing Maternity and Child Health Care Institute, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Qingyi Zhu
- grid.459791.70000 0004 1757 7869Nanjing Maternity and Child Health Care Institute, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China ,grid.459791.70000 0004 1757 7869Department of Obstetrics, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Xiaodie Yao
- grid.459791.70000 0004 1757 7869Nanjing Maternity and Child Health Care Institute, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Zhonghua Shi
- Department of Obstetrics, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China.
| | - Juan Wen
- Nanjing Maternity and Child Health Care Institute, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China.
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Das L, Shekhar S, Chandrani P, Varma AK. In silico structural analysis of secretory clusterin to assess pathogenicity of mutations identified in the evolutionarily conserved regions. J Biomol Struct Dyn 2023; 41:469-478. [PMID: 34821197 DOI: 10.1080/07391102.2021.2007791] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Clusterin (CLU) is a secreted glycoprotein, heterodimeric in nature, and is expressed in a wide variety of tissues and body fluids such as serum and plasma. CLU has also been known to be a promising biomarker for cell death, malignancy, cancer progression, and resistance development. However, the lack of a CLU crystal structure obstructs understanding the possible role of reported mutations on the structure, and the subsequent effects on downstream signaling pathways and cancer progression. Considering the importance of crystal structure, a model structure of the pre-secretory isoform of CLU was built to predict the effect of mutations at the molecular level. Ab initio model was built using RaptorX, and loop refinement and energy minimization were carried out with ModLoop, ModRefiner, and GalaxyWeb servers. The cancer associated mutational spectra of CLU was retrieved from the cBioPortal server and 117 unique missense mutations were identified. Evolutionarily conserved regions and pathogenicity of mutations identified in CLU were analyzed using ConSurf and Rhapsody, respectively. Furthermore, sequence and structure-based mutational analysis were carried out with iSTABLE, DynaMut and PremPS servers. Molecular dynamics simulations were carried out with GROMACS for 50 ns to determine the stability of the wild type and mutant protein structures. A dynamically stable model structure of pre-secretory CLU (psCLU) which has high concurrence with the sequence based secondary structure predictions has been explored. Changes in the intra-atomic interactions and folding pattern between wild type and mutant structures were observed. To our conclusion, eleven mutations with the highest structural and functional significance have been predicted to have pathogenic and deleterious effects.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Lipi Das
- Advanced Centre for Treatment, Research and Education in Cancer, Navi Mumbai, India.,Homi Bhabha National Institute, Training School Complex, Mumbai, India
| | - Shashank Shekhar
- Supercomputing Facility for Bioinformatics & Computational Biology, Indian Institute of Technology, New Delhi, India
| | - Pratik Chandrani
- Advanced Centre for Treatment, Research and Education in Cancer, Navi Mumbai, India.,Homi Bhabha National Institute, Training School Complex, Mumbai, India.,Medical Oncology Molecular Lab, Tata Memorial Hospital, Mumbai, India
| | - Ashok K Varma
- Advanced Centre for Treatment, Research and Education in Cancer, Navi Mumbai, India.,Homi Bhabha National Institute, Training School Complex, Mumbai, India
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Kim YM, Park S, Choi SY, Oh SB, Jung M, Pack CG, Hwang JJ, Tak E, Lee JY. Clusterin Binding Modulates the Aggregation and Neurotoxicity of Amyloid-β(1-42). Mol Neurobiol 2022; 59:6228-6244. [PMID: 35904715 DOI: 10.1007/s12035-022-02973-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 07/20/2022] [Indexed: 11/28/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by the accumulation of amyloid-β (Aβ) aggregates in the brain. Clusterin (CLU), also known as apolipoprotein J, is a potent risk factor associated with AD pathogenesis, in which Aβ aggregation is essentially involved. We observed close colocalization of CLU and Aβ(1-42) (Aβ42) in parenchymal amyloid plaques or vascular amyloid deposits in the brains of human amyloid precursor protein (hAPP)-transgenic Tg2576 mice. Therefore, to elucidate the binding interaction between CLU and Aβ42 and its impact on amyloid aggregation and toxicity, the two synthetic proteins were incubated together under physiological conditions, and their structural and morphological variations were investigated using biochemical, biophysical, and microscopic analyses. Synthetic CLU spontaneously bound to different possible variants of Aβ42 aggregates with very high affinity (Kd = 2.647 nM) in vitro to form solid CLU-Aβ42 complexes. This CLU binding prevented further aggregation of Aβ42 into larger oligomers or fibrils, enriching the population of smaller Aβ42 oligomers and protofibrils and monomers. CLU either alleviated or augmented Aβ42-induced cytotoxicity and apoptosis in the neuroblastoma-derived SH-SY5Y and N2a cells, depending on the incubation period and the molar ratio of CLU:Aβ42 involved in the reaction before addition to the cells. Thus, the effects of CLU on Aβ42-induced cytotoxicity were likely determined by the extent to which it bound and sequestered toxic Aβ42 oligomers or protofibrils. These findings suggest that CLU could influence amyloid neurotoxicity and pathogenesis by modulating Aβ aggregation.
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Affiliation(s)
- Yun-Mi Kim
- Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea.,Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - SuJi Park
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - Su Yeon Choi
- Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea.,Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - Shin Bi Oh
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - MinKyo Jung
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - Chan-Gi Pack
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea.,Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Jung Jin Hwang
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea
| | - Eunyoung Tak
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea.,Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Joo-Yong Lee
- Asan Institute for Life Sciences, Asan Medical Center, Seoul, 05505, Republic of Korea. .,Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea.
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Yuste-Checa P, Bracher A, Hartl FU. The chaperone Clusterin in neurodegeneration-friend or foe? Bioessays 2022; 44:e2100287. [PMID: 35521968 DOI: 10.1002/bies.202100287] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 12/30/2022]
Abstract
Fibrillar protein aggregates are the pathological hallmark of a group of age-dependent neurodegenerative conditions, including Alzheimer's and Parkinson's disease. Aggregates of the microtubule-associated protein Tau are observed in Alzheimer's disease and primary tauopathies. Tau pathology propagates from cell to cell in a prion-like process that is likely subject to modulation by extracellular chaperones such as Clusterin. We recently reported that Clusterin delayed Tau fibril formation but enhanced the activity of Tau oligomers to seed aggregation of endogenous Tau in a cellular model. In contrast, Clusterin inhibited the propagation of α-Synuclein aggregates associated with Parkinson's disease. These findings raise the possibility of a mechanistic link between Clusterin upregulation observed in Alzheimer's disease and the progression of Tau pathology. Here we review the diverse functions of Clusterin in the pathogenesis of neurodegenerative diseases, focusing on evidence that Clusterin may act either as a suppressor or enhancer of pathology.
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Affiliation(s)
- Patricia Yuste-Checa
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
| | - Andreas Bracher
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - F Ulrich Hartl
- Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
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Berdowska I, Matusiewicz M, Krzystek-Korpacka M. HDL Accessory Proteins in Parkinson’s Disease—Focusing on Clusterin (Apolipoprotein J) in Regard to Its Involvement in Pathology and Diagnostics—A Review. Antioxidants (Basel) 2022; 11:antiox11030524. [PMID: 35326174 PMCID: PMC8944556 DOI: 10.3390/antiox11030524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 02/04/2023] Open
Abstract
Parkinson’s disease (PD)—a neurodegenerative disorder (NDD) characterized by progressive destruction of dopaminergic neurons within the substantia nigra of the brain—is associated with the formation of Lewy bodies containing mainly α-synuclein. HDL-related proteins such as paraoxonase 1 and apolipoproteins A1, E, D, and J are implicated in NDDs, including PD. Apolipoprotein J (ApoJ, clusterin) is a ubiquitous, multifunctional protein; besides its engagement in lipid transport, it modulates a variety of other processes such as immune system functionality and cellular death signaling. Furthermore, being an extracellular chaperone, ApoJ interacts with proteins associated with NDD pathogenesis (amyloid β, tau, and α-synuclein), thus modulating their properties. In this review, the association of clusterin with PD is delineated, with respect to its putative involvement in the pathological mechanism and its application in PD prognosis/diagnosis.
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Affiliation(s)
- Izabela Berdowska
- Correspondence: (I.B.); (M.M.); Tel.: +48-71-784-13-92 (I.B.); +48-71-784-13-70 (M.M.)
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Spatharas PM, Nasi GI, Tsiolaki PL, Theodoropoulou MK, Papandreou NC, Hoenger A, Trougakos IP, Iconomidou VA. Clusterin in Alzheimer's disease: An amyloidogenic inhibitor of amyloid formation? Biochim Biophys Acta Mol Basis Dis 2022; 1868:166384. [DOI: 10.1016/j.bbadis.2022.166384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/20/2022] [Accepted: 03/07/2022] [Indexed: 12/14/2022]
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Wilson MR, Satapathy S, Jeong S, Fini ME. Clusterin, other extracellular chaperones, and eye disease. Prog Retin Eye Res 2021; 89:101032. [PMID: 34896599 DOI: 10.1016/j.preteyeres.2021.101032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 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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Rostagno A, Calero M, Holton JL, Revesz T, Lashley T, Ghiso J. Association of clusterin with the BRI2-derived amyloid molecules ABri and ADan. Neurobiol Dis 2021; 158:105452. [PMID: 34298087 PMCID: PMC8440498 DOI: 10.1016/j.nbd.2021.105452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 06/30/2021] [Accepted: 07/18/2021] [Indexed: 10/20/2022] Open
Abstract
Familial British and Danish dementias (FBD and FDD) share striking neuropathological similarities with Alzheimer's disease (AD), including intraneuronal neurofibrillary tangles as well as parenchymal and vascular amyloid deposits. Multiple amyloid associated proteins with still controversial role in amyloidogenesis colocalize with the structurally different amyloid peptides ABri in FBD, ADan in FDD, and Aβ in AD. Genetic variants and plasma levels of one of these associated proteins, clusterin, have been identified as risk factors for AD. Clusterin is known to bind soluble Aβ in biological fluids, facilitate its brain clearance, and prevent its aggregation. The current work identifies clusterin as the major ABri- and ADan-binding protein and provides insight into the biochemical mechanisms leading to the association of clusterin with ABri and ADan deposits. Mirroring findings in AD, the studies corroborate clusterin co-localization with cerebral parenchymal and vascular amyloid deposits in both disorders. Ligand affinity chromatography with downstream Western blot and amino acid sequence analyses unequivocally identified clusterin as the major ABri- and ADan-binding plasma protein. ELISA highlighted a specific saturable binding of clusterin to ABri and ADan with low nanomolar Kd values within the same range as those previously demonstrated for the clusterin-Aβ interaction. Consistent with its chaperone activity, thioflavin T binding assays clearly showed a modulatory effect of clusterin on ABri and ADan aggregation/fibrillization properties. Our findings, together with the known multifunctional activity of clusterin and its modulatory activity on the complex cellular pathways leading to oxidative stress, mitochondrial dysfunction, and the induction of cell death mechanisms - all known pathogenic features of these protein folding disorders - suggests the likelihood of a more complex role and a translational potential for the apolipoprotein in the amelioration/prevention of these pathogenic mechanisms.
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Affiliation(s)
- Agueda Rostagno
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Miguel Calero
- Instituto de Salud Carlos III, 28029 Madrid, Spain; Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), 28031 Madrid, Spain; Alzheimer's Center Reina Sofia Foundation - CIEN Foundation, 28031 Madrid, Spain
| | - Janice L Holton
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Tamas Revesz
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK; Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Tammaryn Lashley
- The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK; Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Jorge Ghiso
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA; Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA.
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12
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Marozzi M, Parnigoni A, Negri A, Viola M, Vigetti D, Passi A, Karousou E, Rizzi F. Inflammation, Extracellular Matrix Remodeling, and Proteostasis in Tumor Microenvironment. Int J Mol Sci 2021; 22:ijms22158102. [PMID: 34360868 PMCID: PMC8346982 DOI: 10.3390/ijms22158102] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/11/2021] [Accepted: 07/26/2021] [Indexed: 12/12/2022] Open
Abstract
Cancer is a multifaceted and complex pathology characterized by uncontrolled cell proliferation and decreased apoptosis. Most cancers are recognized by an inflammatory environment rich in a myriad of factors produced by immune infiltrate cells that induce host cells to differentiate and to produce a matrix that is more favorable to tumor cells’ survival and metastasis. As a result, the extracellular matrix (ECM) is changed in terms of macromolecules content, degrading enzymes, and proteins. Altered ECM components, derived from remodeling processes, interact with a variety of surface receptors triggering intracellular signaling that, in turn, cancer cells exploit to their own benefit. This review aims to present the role of different aspects of ECM components in the tumor microenvironment. Particularly, we highlight the effect of pro- and inflammatory factors on ECM degrading enzymes, such as metalloproteases, and in a more detailed manner on hyaluronan metabolism and the signaling pathways triggered by the binding of hyaluronan with its receptors. In addition, we sought to explore the role of extracellular chaperones, especially of clusterin which is one of the most prominent in the extracellular space, in proteostasis and signaling transduction in the tumor microenvironment. Although the described tumor microenvironment components have different biological roles, they may engage common signaling pathways that favor tumor growth and metastasis.
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Affiliation(s)
- Marina Marozzi
- Department of Medicine and Surgery, University of Parma, Via Gramsci 14, 43125 Parma, Italy; (M.M.); (A.N.); (F.R.)
| | - Arianna Parnigoni
- Department of Medicine and Surgery, University of Insubria, Via J.H. Dunant 5, 21100 Varese, Italy; (A.P.); (M.V.); (D.V.); (A.P.)
| | - Aide Negri
- Department of Medicine and Surgery, University of Parma, Via Gramsci 14, 43125 Parma, Italy; (M.M.); (A.N.); (F.R.)
| | - Manuela Viola
- Department of Medicine and Surgery, University of Insubria, Via J.H. Dunant 5, 21100 Varese, Italy; (A.P.); (M.V.); (D.V.); (A.P.)
| | - Davide Vigetti
- Department of Medicine and Surgery, University of Insubria, Via J.H. Dunant 5, 21100 Varese, Italy; (A.P.); (M.V.); (D.V.); (A.P.)
| | - Alberto Passi
- Department of Medicine and Surgery, University of Insubria, Via J.H. Dunant 5, 21100 Varese, Italy; (A.P.); (M.V.); (D.V.); (A.P.)
| | - Evgenia Karousou
- Department of Medicine and Surgery, University of Insubria, Via J.H. Dunant 5, 21100 Varese, Italy; (A.P.); (M.V.); (D.V.); (A.P.)
- Correspondence:
| | - Federica Rizzi
- Department of Medicine and Surgery, University of Parma, Via Gramsci 14, 43125 Parma, Italy; (M.M.); (A.N.); (F.R.)
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Torres-Arancivia CM, Chang D, Hackett WE, Zaia J, Connors LH. Glycosylation of Serum Clusterin in Wild-Type Transthyretin-Associated (ATTRwt) Amyloidosis: A Study of Disease-Associated Compositional Features Using Mass Spectrometry Analyses. Biochemistry 2020; 59:4367-4378. [PMID: 33141553 PMCID: PMC8082438 DOI: 10.1021/acs.biochem.0c00590] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Wild-type transthyretin-associated (ATTRwt) amyloidosis is an age-related disease that causes heart failure in older adults. This disease frequently features cardiac amyloid fibril deposits that originate from dissociation of the tetrameric protein, transthyretin (TTR). Unlike hereditary TTR (ATTRm) amyloidosis, where amino acid replacements destabilize the native protein, in ATTRwt amyloidosis, amyloid-forming TTR lacks protein sequence alterations. The initiating cause of fibril formation in ATTRwt amyloidosis is unclear, and thus, it seems plausible that other factors are involved in TTR misfolding and unregulated accumulation of wild-type TTR fibrils. We believe that clusterin (CLU, UniProtKB P10909), a plasma circulating glycoprotein, plays a role in the pathobiology of ATTRwt amyloidosis. Previously, we have suggested a role for CLU in ATTRwt amyloidosis based on our studies showing that (1) CLU codeposits with non-native TTR in amyloid fibrils from ATTRwt cardiac tissue, (2) CLU interacts only with non-native (monomeric and aggregated) forms of TTR, and (3) CLU serum levels in patients with ATTRwt are significantly lower compared to healthy controls. In the present study, we provide comprehensive detail of compositional findings from mass spectrometry analyses of amino acid and glycan content of CLU purified from ATTRwt and control sera. The characterization of oligosaccharide content in serum CLU derived from patients with ATTRwt amyloidosis is novel data. Moreover, results comparing CLU oligosaccharide variations between patient and healthy controls are original and provide further evidence for the role of CLU in ATTRwt pathobiology, possibly linked to disease-specific structural features that limit the chaperoning capacity of CLU.
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Satapathy S, Dabbs RA, Wilson MR. Rapid high-yield expression and purification of fully post-translationally modified recombinant clusterin and mutants. Sci Rep 2020; 10:14243. [PMID: 32859921 PMCID: PMC7455699 DOI: 10.1038/s41598-020-70990-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 07/30/2020] [Indexed: 11/17/2022] Open
Abstract
The first described and best known mammalian secreted chaperone, abundant in human blood, is clusterin. Recent independent studies are now exploring the potential use of clusterin as a therapeutic in a variety of disease contexts. In the past, the extensive post-translational processing of clusterin, coupled with its potent binding to essentially any misfolded protein, have meant that its expression as a fully functional recombinant protein has been very difficult. We report here the first rapid and high-yield system for the expression and purification of fully post-translationally modified and chaperone-active clusterin. Only 5–6 days is required from initial transfection to harvest of the protein-free culture medium containing the recombinant product. Purification to near-homogeneity can then be accomplished in a single affinity purification step and the yield for wild type human clusterin is of the order of 30–40 mg per litre of culture. We have also shown that this system can be used to quickly express and purify custom-designed clusterin mutants. These advances dramatically increase the feasibility of detailed structure–function analysis of the clusterin molecule and will facilitate identification of those specific regions responsible for the interactions of clusterin with receptors and other molecules.
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Affiliation(s)
- Sandeep Satapathy
- Illawarra Health and Medical Research Institute, School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia.,Molecular Horizons Research Institute, University of Wollongong, Rm 313, Building 42 (Molecular Horizons), Northfields Avenue, Wollongong, NSW, 2522, Australia
| | - Rebecca A Dabbs
- Burnett Institute, 85 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Mark R Wilson
- Illawarra Health and Medical Research Institute, School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia. .,Molecular Horizons Research Institute, University of Wollongong, Rm 313, Building 42 (Molecular Horizons), Northfields Avenue, Wollongong, NSW, 2522, Australia.
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15
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Chaplot K, Jarvela TS, Lindberg I. Secreted Chaperones in Neurodegeneration. Front Aging Neurosci 2020; 12:268. [PMID: 33192447 PMCID: PMC7481362 DOI: 10.3389/fnagi.2020.00268] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/03/2020] [Indexed: 12/11/2022] Open
Abstract
Protein homeostasis, or proteostasis, is a combination of cellular processes that govern protein quality control, namely, protein translation, folding, processing, and degradation. Disruptions in these processes can lead to protein misfolding and aggregation. Proteostatic disruption can lead to cellular changes such as endoplasmic reticulum or oxidative stress; organelle dysfunction; and, if continued, to cell death. A majority of neurodegenerative diseases involve the pathologic aggregation of proteins that subverts normal neuronal function. While prior reviews of neuronal proteostasis in neurodegenerative processes have focused on cytoplasmic chaperones, there is increasing evidence that chaperones secreted both by neurons and other brain cells in the extracellular - including transsynaptic - space play important roles in neuronal proteostasis. In this review, we will introduce various secreted chaperones involved in neurodegeneration. We begin with clusterin and discuss its identification in various protein aggregates, and the use of increased cerebrospinal fluid (CSF) clusterin as a potential biomarker and as a potential therapeutic. Our next secreted chaperone is progranulin; polymorphisms in this gene represent a known genetic risk factor for frontotemporal lobar degeneration, and progranulin overexpression has been found to be effective in reducing Alzheimer's- and Parkinson's-like neurodegenerative phenotypes in mouse models. We move on to BRICHOS domain-containing proteins, a family of proteins containing highly potent anti-amyloidogenic activity; we summarize studies describing the biochemical mechanisms by which recombinant BRICHOS protein might serve as a therapeutic agent. The next section of the review is devoted to the secreted chaperones 7B2 and proSAAS, small neuronal proteins which are packaged together with neuropeptides and released during synaptic activity. Since proteins can be secreted by both classical secretory and non-classical mechanisms, we also review the small heat shock proteins (sHsps) that can be secreted from the cytoplasm to the extracellular environment and provide evidence for their involvement in extracellular proteostasis and neuroprotection. Our goal in this review focusing on extracellular chaperones in neurodegenerative disease is to summarize the most recent literature relating to neurodegeneration for each secreted chaperone; to identify any common mechanisms; and to point out areas of similarity as well as differences between the secreted chaperones identified to date.
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Affiliation(s)
| | | | - Iris Lindberg
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, University of Maryland, Baltimore, Baltimore, MD, United States
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16
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Paraoan L, Sharif U, Carlsson E, Supharattanasitthi W, Mahmud NM, Kamalden TA, Hiscott P, Jackson M, Grierson I. Secretory proteostasis of the retinal pigmented epithelium: Impairment links to age-related macular degeneration. Prog Retin Eye Res 2020; 79:100859. [PMID: 32278708 DOI: 10.1016/j.preteyeres.2020.100859] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/24/2020] [Accepted: 03/26/2020] [Indexed: 12/19/2022]
Abstract
Secretory proteostasis integrates protein synthesis, processing, folding and trafficking pathways that are essential for efficient cellular secretion. For the retinal pigment epithelium (RPE), secretory proteostasis is of vital importance for the maintenance of the structural and functional integrity of apical (photoreceptors) and basal (Bruch's membrane/choroidal blood supply) sides of the environment it resides in. This integrity is achieved through functions governed by RPE secreted proteins, which include extracellular matrix modelling/remodelling, angiogenesis and immune response modulation. Impaired RPE secretory proteostasis affects not only the extracellular environment, but leads to intracellular protein aggregation and ER-stress with subsequent cell death. Ample recent evidence implicates dysregulated proteostasis as a key factor in the development of age-related macular degeneration (AMD), the leading cause of blindness in the developed world, and research aiming to characterise the roles of various proteins implicated in AMD-associated dysregulated proteostasis unveiled unexpected facets of the mechanisms involved in degenerative pathogenesis. This review analyses cellular processes unveiled by the study of the top 200 transcripts most abundantly expressed by the RPE/choroid in the light of the specialised secretory nature of the RPE. Functional roles of these proteins and the mechanisms of their impaired secretion, due to age and genetic-related causes, are analysed in relation to AMD development. Understanding the importance of RPE secretory proteostasis in relation to maintaining retinal health and how it becomes impaired in disease is of paramount importance for the development and assessment of future therapeutic advancements involving gene and cell therapies.
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Affiliation(s)
- Luminita Paraoan
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.
| | - Umar Sharif
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Emil Carlsson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Wasu Supharattanasitthi
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom; Department of Physiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Nur Musfirah Mahmud
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Tengku Ain Kamalden
- Eye Research Centre, Department of Ophthalmology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Paul Hiscott
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Malcolm Jackson
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Ian Grierson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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17
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Redwan EM, AlJaddawi AA, Uversky VN. Structural disorder in the proteome and interactome of Alkhurma virus (ALKV). Cell Mol Life Sci 2019; 76:577-608. [PMID: 30443749 PMCID: PMC7079808 DOI: 10.1007/s00018-018-2968-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 10/30/2018] [Accepted: 11/05/2018] [Indexed: 12/13/2022]
Abstract
Infection by the Alkhurma virus (ALKV) leading to the Alkhurma hemorrhagic fever is a common thread in Saudi Arabia, with no efficient treatment or prevention available as of yet. Although the rational drug design traditionally uses information on known 3D structures of viral proteins, intrinsically disordered proteins (i.e., functional proteins that do not possess unique 3D structures), with their multitude of disorder-dependent functions, are crucial for the biology of viruses. Here, viruses utilize disordered regions in their invasion of the host organisms and in hijacking and repurposing of different host systems. Furthermore, the ability of viruses to efficiently adjust and accommodate to their hostile habitats is also intrinsic disorder-dependent. However, little is currently known on the level of penetrance and functional utilization of intrinsic disorder in the ALKV proteome. To fill this gap, we used here multiple computational tools to evaluate the abundance of intrinsic disorder in the ALKV genome polyprotein. We also analyzed the peculiarities of intrinsic disorder predisposition of the individual viral proteins, as well as human proteins known to be engaged in interaction with the ALKV proteins. Special attention was paid to finding a correlation between protein functionality and structural disorder. To the best of our knowledge, this work represents the first systematic study of the intrinsic disorder status of ALKV proteome and interactome.
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Affiliation(s)
- Elrashdy M Redwan
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah, Saudi Arabia.
| | - Abdullah A AlJaddawi
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah, Saudi Arabia
| | - Vladimir N Uversky
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, P.O. Box 80203, Jeddah, Saudi Arabia.
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
- Laboratory of New Methods in Biology, Institute for Biological Instrumentation, Russian Academy of Sciences, Pushchino, 142290, Moscow Region, Russia.
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18
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Yu V, Bhattacharya D, Webster A, Bauskar A, Flowers C, Heur M, Chintala SK, Itakura T, Wilson MR, Barr JT, Jeong S, Wang M, Fini ME. Clusterin from human clinical tear samples: Positive correlation between tear concentration and Schirmer strip test results. Ocul Surf 2018; 16:478-486. [PMID: 30077709 PMCID: PMC6175631 DOI: 10.1016/j.jtos.2018.08.001] [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: 02/22/2018] [Revised: 07/24/2018] [Accepted: 08/01/2018] [Indexed: 01/02/2023]
Abstract
PURPOSE To investigate the relationship between tear concentration of the homeostatic protein clusterin (CLU) and dry eye signs and symptoms, and to characterize tear CLU protein. METHODS Two independent studies were conducted, one in Tucson (44 subjects), the other in Los Angeles (52 subjects). A cohort study design was employed to enroll patients without regard to dry eye diagnosis. Dry eye signs and symptoms were assessed using clinical tests. Tear samples were collected by Schirmer strip, and also by micropipette at slit lamp when possible. CLU from both sample types was quantified by immunoassay. The relationship between CLU concentration and clinical test scores was determined by Pearson's correlation coefficient (for individual eyes) and multiple linear regression analysis (including both eyes). CLU was also evaluated biochemically by western blotting. RESULTS In the Tucson cohort, a positive correlation was observed between tear CLU concentration and results of the Schirmer strip test, a measure of tear flow (p = 0.021 includes both eyes). This result was corroborated in the Los Angeles cohort (p = 0.013). The mean tear CLU concentration was 31 ± 14 μg/mL (n = 18 subjects, 33 eyes; range = 7-48 μg/mL). CLU from clinical tear samples appeared biochemically similar to CLU from a non-clinical tear sample and from blood plasma. CONCLUSIONS Results support the hypothesis that an optimal concentration of tear CLU is important for ocular surface health, and that this drops below the effective threshold in dry eye. Tear CLU measurement might identify patients that could benefit from supplementation. Information about concentration will aid development of therapeutic dosage parameters.
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Affiliation(s)
- Valerie Yu
- MD Program, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Dhruva Bhattacharya
- Department of Ophthalmology & Vision Science, University of Arizona College of Medicine, Tucson, AZ, USA
| | - Andrew Webster
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Aditi Bauskar
- PhD Program in Medical Biology, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Charles Flowers
- USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Martin Heur
- USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Shravan K Chintala
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Tatsuo Itakura
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Mark R Wilson
- Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - Joseph T Barr
- The Ohio State University College of Optometry, Columbus, OH, USA
| | - Shinwu Jeong
- USC Institute for Genetic Medicine, USC Roski Eye Institute and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Mingwu Wang
- Department of Ophthalmology & Vision Science, University of Arizona College of Medicine, Tucson, AZ, USA
| | - M Elizabeth Fini
- USC Institute for Genetic Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA.
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Fernández-de-Retana S, Cano-Sarabia M, Marazuela P, Sánchez-Quesada JL, Garcia-Leon A, Montañola A, Montaner J, Maspoch D, Hernández-Guillamon M. Characterization of ApoJ-reconstituted high-density lipoprotein (rHDL) nanodisc for the potential treatment of cerebral β-amyloidosis. Sci Rep 2017; 7:14637. [PMID: 29116115 PMCID: PMC5677083 DOI: 10.1038/s41598-017-15215-w] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/24/2017] [Indexed: 01/12/2023] Open
Abstract
Cerebral β-amyloidosis is a major feature of Alzheimer’s disease (AD), characterized by the accumulation of β-amyloid protein (Aβ) in the brain. Several studies have implicated lipid/lipoprotein metabolism in the regulation of β-amyloidosis. In this regard, HDL (High Density Lipoprotein)-based therapies could ameliorate pathological features associated with AD. As apolipoprotein J (ApoJ) is a natural chaperone that interacts with Aβ, avoiding its aggregation and toxicity, in this study we propose to prepare reconstituted rHDL-rApoJ nanoparticles by assembling phospholipids with recombinant human ApoJ (rApoJ). Hence, rHDL particles were prepared using the cholate dialysis method and characterized by N-PAGE, dynamic light scattering, circular dichroism and electron transmission microscopy. The preparation of rHDL particles showed two-sized populations with discoidal shape. Functionally, rHDL-rApoJ maintained the ability to prevent the Aβ fibrillization and mediated a higher cholesterol efflux from cultured macrophages. Fluorescently-labelled rHDL-rApoJ nanoparticles were intravenously administrated in mice and their distribution over time was determined using an IVIS Xenogen® imager. It was confirmed that rHDL-rApoJ accumulated in the cranial region, especially in old transgenic mice presenting a high cerebral Aβ load. In conclusion, we have standardized a reproducible protocol to produce rHDL-rApoJ nanoparticles, which may be potentially considered as a therapeutic option for β-amyloid-related pathologies.
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Affiliation(s)
- Sofía Fernández-de-Retana
- Neurovascular Research Laboratory, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Mary Cano-Sarabia
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and the Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, Spain.
| | - Paula Marazuela
- Neurovascular Research Laboratory, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Jose Luis Sánchez-Quesada
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de Sant Pau (IIB Sant Pau), Barcelona, Spain
| | - Annabel Garcia-Leon
- Cardiovascular Biochemistry Group, Research Institute of the Hospital de Sant Pau (IIB Sant Pau), Barcelona, Spain
| | - Alex Montañola
- Neurovascular Research Laboratory, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Joan Montaner
- Neurovascular Research Laboratory, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Daniel Maspoch
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and the Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), 08100, Barcelona, Spain
| | - Mar Hernández-Guillamon
- Neurovascular Research Laboratory, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona, Barcelona, Spain.
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20
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Matukumalli SR, Tangirala R, Rao CM. Clusterin: full-length protein and one of its chains show opposing effects on cellular lipid accumulation. Sci Rep 2017; 7:41235. [PMID: 28120874 PMCID: PMC5264606 DOI: 10.1038/srep41235] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 12/16/2016] [Indexed: 12/31/2022] Open
Abstract
Proteins, made up of either single or multiple chains, are designed to carry out specific biological functions. We found an interesting example of a two-chain protein where administration of one of its chains leads to a diametrically opposite outcome than that reported for the full-length protein. Clusterin is a highly glycosylated protein consisting of two chains, α- and β-clusterin. We have investigated the conformational features, cellular localization, lipid accumulation, in vivo effects and histological changes upon administration of recombinant individual chains of clusterin. We demonstrate that recombinant α- and β-chains exhibit structural and functional differences and differ in their sub-cellular localization. Full-length clusterin is known to lower lipid levels. In contrast, we find that β-chain-treated cells accumulate 2-fold more lipid than controls. Interestingly, α-chain-treated cells do not show such increase. Rabbits injected with β-chain, but not α-chain, show ~40% increase in weight, with adipocyte hypertrophy, liver and kidney steatosis. Many, sometimes contrasting, roles are ascribed to clusterin in obesity, metabolic syndrome and related conditions. Our findings of differential localization and activities of individual chains of clusterin should help in understanding better the roles of clusterin in metabolism.
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Affiliation(s)
| | | | - C. M. Rao
- CSIR- Centre for Cellular and Molecular Biology, Hyderabad, 500007, India
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21
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Toll-like receptor 4 signaling is required for clusterin-induced tumor necrosis factor-α secretion in macrophage. Biochem Biophys Res Commun 2017; 482:1407-1412. [DOI: 10.1016/j.bbrc.2016.12.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 12/07/2016] [Indexed: 11/17/2022]
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Abstract
INTRODUCTION Clusterin (CLU) is a stress-activated, ATP-independent molecular chaperone, normally secreted from cells, that is up-regulated in Alzheimer disease and in many cancers. It plays important roles in protein homeostasis/proteostasis, inhibition of cell death pathways, and modulation of pro-survival signalling and transcriptional networks. Changes in the CLU gene locus are highly associated with Alzheimer disease, and many therapy-resistant cancers over-express CLU. The extensive post-translational processing and heterogeneous oligomerization of CLU have so far prevented any definitive structure determination. This in turn has meant that targeting CLU with small molecule inhibitors is challenging. Therefore, inhibiting CLU at the gene-expression level using siRNA or antisense is a valid approach to inhibit its function. Areas covered: This article reviews recent advances regarding the role of CLU in proteostasis, cellular trafficking, human diseases, and signalling pathways involved in oncogenesis. It addresses the rationale for CLU as a therapeutic target in cancer, and the current status of pre-clinical and clinical studies using CLU antisense inhibitor OGX011. Expert opinion: Discusses challenges facing the therapeutic targeting of CLU including rapid changes in the treatment landscape for prostate cancer with multiple new FDA approved drugs, selection of windows of intervention, and potential side effects when silencing CLU expression.
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Affiliation(s)
- Mark R Wilson
- a School of Biological Sciences , University of Wollongong , Wollongong , Australia
| | - Amina Zoubeidi
- b Department of Urologic Sciences, Vancouver Prostate Centre , University of British Columbia and Vancouver General Hospital , Vancouver , Canada
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Alowolodu O, Johnson G, Alashwal L, Addou I, Zhdanova IV, Uversky VN. Intrinsic disorder in spondins and some of their interacting partners. INTRINSICALLY DISORDERED PROTEINS 2016; 4:e1255295. [PMID: 28232900 DOI: 10.1080/21690707.2016.1255295] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 10/22/2016] [Accepted: 10/27/2016] [Indexed: 12/28/2022]
Abstract
Spondins, which are proteins that inhibit and promote adherence of embryonic cells so as to aid axonal growth are part of the thrombospondin-1 family. Spondins function in several important biological processes, such as apoptosis, angiogenesis, etc. Spondins constitute a thrombospondin subfamily that includes F-spondin, a protein that interacts with Aβ precursor protein and inhibits its proteolytic processing; R-spondin, a 4-membered group of proteins that regulates Wnt pathway and have other functions, such as regulation of kidney proliferation, induction of epithelial proliferation, the tumor suppressant action; M-spondin that mediates mechanical linkage between the muscles and apodemes; and the SCO-spondin, a protein important for neuronal development. In this study, we investigated intrinsic disorder status of human spondins and their interacting partners, such as members of the LRP family, LGR family, Frizzled family, and several other binding partners in order to establish the existence and importance of disordered regions in spondins and their interacting partners by conducting a detailed analysis of their sequences, finding disordered regions, and establishing a correlation between their structure and biological functions.
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Affiliation(s)
- Oluwole Alowolodu
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida , Tampa, FL, USA
| | - Gbemisola Johnson
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida , Tampa, FL, USA
| | - Lamis Alashwal
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida , Tampa, FL, USA
| | - Iqbal Addou
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida , Tampa, FL, USA
| | - Irina V Zhdanova
- Department of Anatomy & Neurobiology, Boston University School of Medicine , Boston, MA, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; USF Health Byrd Alzheimer Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
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Rohne P, Prochnow H, Koch-Brandt C. The CLU-files: disentanglement of a mystery. Biomol Concepts 2016; 7:1-15. [PMID: 26673020 DOI: 10.1515/bmc-2015-0026] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/05/2015] [Indexed: 01/03/2023] Open
Abstract
The multifaceted protein clusterin (CLU) has been challenging researchers for more than 35 years. The characterization of CLU as a molecular chaperone was one of the major breakthroughs in CLU research. Today, secretory clusterin (sCLU), also known as apolipoprotein J (apoJ), is considered one of the most important extracellular chaperones ever found. It is involved in a broad range of physiological and pathophysiological functions, where it exerts a cytoprotective role. Descriptions of various forms of intracellular CLU have led to further and even contradictory functions. To untangle the current state of knowledge of CLU, this review will combine old views in the field, with new discoveries to highlight the nature and function of this fascinating protein(s). In this review, we further describe the expression and subcellular location of various CLU forms. Moreover, we discuss recent insights into the structure of CLU and assess how structural properties as well as the redox environment determine the chaperone activity of CLU. Eventually, the review connects the biochemistry and molecular cell biology of CLU with medical aspects, to formulate a hypothesis of a CLU function in health and disease.
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DeForte S, Uversky VN. Order, Disorder, and Everything in Between. Molecules 2016; 21:molecules21081090. [PMID: 27548131 PMCID: PMC6274243 DOI: 10.3390/molecules21081090] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 02/04/2023] Open
Abstract
In addition to the “traditional” proteins characterized by the unique crystal-like structures needed for unique functions, it is increasingly recognized that many proteins or protein regions (collectively known as intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs)), being biologically active, do not have a specific 3D-structure in their unbound states under physiological conditions. There are also subtler categories of disorder, such as conditional (or dormant) disorder and partial disorder. Both the ability of a protein/region to fold into a well-ordered functional unit or to stay intrinsically disordered but functional are encoded in the amino acid sequence. Structurally, IDPs/IDPRs are characterized by high spatiotemporal heterogeneity and exist as dynamic structural ensembles. It is important to remember, however, that although structure and disorder are often treated as binary states, they actually sit on a structural continuum.
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Affiliation(s)
- Shelly DeForte
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
| | - Vladimir N Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
- USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg 194064, Russia.
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Fini ME, Bauskar A, Jeong S, Wilson MR. Clusterin in the eye: An old dog with new tricks at the ocular surface. Exp Eye Res 2016; 147:57-71. [PMID: 27131907 DOI: 10.1016/j.exer.2016.04.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 12/30/2022]
Abstract
The multifunctional protein clusterin (CLU) was first described in 1983 as a secreted glycoprotein present in ram rete testis fluid that enhanced aggregation ('clustering') of a variety of cells in vitro. It was also independently discovered in a number of other systems. By the early 1990s, CLU was known under many names and its expression had been demonstrated throughout the body, including in the eye. Its homeostatic activities in proteostasis, cytoprotection, and anti-inflammation have been well documented, however its roles in health and disease are still not well understood. CLU is prominent at fluid-tissue interfaces, and in 1996 it was demonstrated to be the most highly expressed transcript in the human cornea, the protein product being localized to the apical layers of the mucosal epithelia of the cornea and conjunctiva. CLU protein is also present in human tears. Using a preclinical mouse model for desiccating stress that mimics human dry eye disease, the authors recently demonstrated that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration in the tears. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to LGALS3 (galectin-3), a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. CLU depletion from the ocular surface epithelia is seen in a variety of inflammatory conditions in humans and mice that lead to squamous metaplasia and a keratinized epithelium. This suggests that CLU might have a specific role in maintaining mucosal epithelial differentiation, an idea that can now be tested using the mouse model for desiccating stress. Most excitingly, the new findings suggest that CLU could serve as a novel biotherapeutic for dry eye disease.
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Affiliation(s)
- M Elizabeth Fini
- USC Institute for Genetic Medicine and Departments of Cell & Neurobiology and Ophthalmology, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA 90089-9037, USA.
| | - Aditi Bauskar
- USC Institute for Genetic Medicine and Graduate Program in Medical Biology, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA 90089-9037, USA.
| | - Shinwu Jeong
- USC Institute for Genetic Medicine and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, 2250 Alcatraz St., Suite 240, Los Angeles, CA 90089-9037, USA.
| | - Mark R Wilson
- Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, New South Wales, 2522 Australia.
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Beeg M, Stravalaci M, Romeo M, Carrá AD, Cagnotto A, Rossi A, Diomede L, Salmona M, Gobbi M. Clusterin Binds to Aβ1-42 Oligomers with High Affinity and Interferes with Peptide Aggregation by Inhibiting Primary and Secondary Nucleation. J Biol Chem 2016; 291:6958-66. [PMID: 26884339 DOI: 10.1074/jbc.m115.689539] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 11/06/2022] Open
Abstract
The aggregation of amyloid β protein (Aβ) is a fundamental pathogenic mechanism leading to the neuronal damage present in Alzheimer disease, and soluble Aβ oligomers are thought to be a major toxic culprit. Thus, better knowledge and specific targeting of the pathways that lead to these noxious species may result in valuable therapeutic strategies. We characterized some effects of the molecular chaperone clusterin, providing new and more detailed evidence of its potential neuroprotective effects. Using a classical thioflavin T assay, we observed a dose-dependent inhibition of the aggregation process. The global analysis of time courses under different conditions demonstrated that clusterin has no effect on the elongation rate but mainly interferes with the nucleation processes (both primary and secondary), reducing the number of nuclei available for further fibril growth. Then, using a recently developed immunoassay based on surface plasmon resonance, we obtained direct evidence of a high-affinity (KD= 1 nm) interaction of clusterin with biologically relevant Aβ1-42oligomers, selectively captured on the sensor chip. Moreover, with the same technology, we observed that substoichiometric concentrations of clusterin prevent oligomer interaction with the antibody 4G8, suggesting that the chaperone shields hydrophobic residues exposed on the oligomeric assemblies. Finally, we found that preincubation with clusterin antagonizes the toxic effects of Aβ1-42oligomers, as evaluated in a recently developedin vivomodel inCaenorhabditis elegans.These data substantiate the interaction of clusterin with biologically active regions exposed on nuclei/oligomers of Aβ1-42, providing a molecular basis for the neuroprotective effects of the chaperone.
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Affiliation(s)
- Marten Beeg
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Matteo Stravalaci
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Margherita Romeo
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Arianna Dorotea Carrá
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Alfredo Cagnotto
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Alessandro Rossi
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Luisa Diomede
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Mario Salmona
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
| | - Marco Gobbi
- From the Department of Molecular Biochemistry and Pharmacology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milan, Italy
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Alnasser HA, Guan Q, Zhang F, Gleave ME, Nguan CYC, Du C. Requirement of clusterin expression for prosurvival autophagy in hypoxic kidney tubular epithelial cells. Am J Physiol Renal Physiol 2016; 310:F160-73. [DOI: 10.1152/ajprenal.00304.2015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/05/2015] [Indexed: 02/08/2023] Open
Abstract
Cellular autophagy is a prosurvival mechanism in the kidney against ischemia-reperfusion injury (IRI), but the molecular pathways that activate the autophagy in ischemic kidneys are not fully understood. Clusterin (CLU) is a chaperone-like protein, and its expression is associated with kidney resistance to IRI. The present study investigated the role of CLU in prosurvival autophagy in the kidney. Renal IRI was induced in mice by clamping renal pedicles at 32°C for 45 min. Hypoxia in renal tubular epithelial cell (TEC) cultures was induced by exposure to a 1% O2 atmosphere. Autophagy was determined by either light chain 3-BII expression with Western blot analysis or light chain 3-green fluorescent protein aggregation with confocal microscopy. Cell apoptosis was determined by flow cytometric analysis. The unfolded protein response was determined by PCR array. Here, we showed that autophagy was significantly activated by IRI in wild-type (WT) but not CLU-deficient kidneys. Similarly, autophagy was activated by hypoxia in human proximal TECs (HKC-8) and WT mouse primary TECs but was impaired in CLU-null TECs. Hypoxia-activated autophagy was CLU dependent and positively correlated with cell survival, and inhibition of autophagy significantly promoted cell death in both HKC-8 and mouse WT/CLU-expressing TECs but not in CLU-null TECs. Further experiments showed that CLU-dependent prosurvival autophagy was associated with activation of the unfolded protein response in hypoxic kidney cells. In conclusion, these data suggest that activation of prosurvival autophagy by hypoxia in kidney cells requires CLU expression and may be a key cytoprotective mechanism of CLU in the protection of the kidney from hypoxia/ischemia-mediated injury.
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Affiliation(s)
- Hatem A. Alnasser
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Qiunong Guan
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Immunity and Infection Research Centre, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada; and
| | - Fan Zhang
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | - Martin E. Gleave
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Prostate Centre, Vancouver, British Columbia, Canada
| | - Christopher Y. C. Nguan
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Caigan Du
- Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
- Immunity and Infection Research Centre, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada; and
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Bauskar A, Mack WJ, Mauris J, Argüeso P, Heur M, Nagel BA, Kolar GR, Gleave ME, Nakamura T, Kinoshita S, Moradian-Oldak J, Panjwani N, Pflugfelder SC, Wilson MR, Fini ME, Jeong S. Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye. PLoS One 2015; 10:e0138958. [PMID: 26402857 PMCID: PMC4581869 DOI: 10.1371/journal.pone.0138958] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/04/2015] [Indexed: 12/02/2022] Open
Abstract
Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU) is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye. Using this mouse model, we show here that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to the galectin LGALS3, a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. These findings define a fundamentally new mechanism for ocular surface protection and suggest CLU as a biotherapeutic for dry eye.
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Affiliation(s)
- Aditi Bauskar
- USC Institute for Genetic Medicine and Graduate Program in Medical Biology, Keck School of Medicine of USC, University of Southern California, Los Angeles, California, United States of America
| | - Wendy J. Mack
- Southern California Clinical & Translational Science Institute and Department of Preventive Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, California, United States of America
| | - Jerome Mauris
- The Schepens Eye Research Institute, Massachusetts Eye & Ear and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Pablo Argüeso
- The Schepens Eye Research Institute, Massachusetts Eye & Ear and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Martin Heur
- USC Eye Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, California, United States of America
| | - Barbara A. Nagel
- Research Microscopy and Histology Core, Department of Pathology, Saint Louis University School of Medicine, St Louis, Missouri, United States of America
| | - Grant R. Kolar
- Department of Pathology and Department of Ophthalmology, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Martin E. Gleave
- The Vancouver Prostate Centre and Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Takahiro Nakamura
- Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shigeru Kinoshita
- Department of Frontier Medical Science and Technology for Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Janet Moradian-Oldak
- Center for Craniofacial Molecular Biology, Division of Biomedical Sciences, University of Southern California, Herman Ostrow School of Dentistry of USC, Los Angeles, California, United States of America
| | - Noorjahan Panjwani
- New England Eye Center/Department of Ophthalmology and Department of Developmental, Molecular & Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Stephen C. Pflugfelder
- Ocular Surface Center, Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, United States of America
| | - Mark R. Wilson
- Illawarra Health and Medical Research Institute, School of Biological Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - M. Elizabeth Fini
- USC Institute for Genetic Medicine and Departments of Cell & Neurobiology and Ophthalmology, Keck School of Medicine of USC, University of Southern California, Los Angeles, California, United States of America
| | - Shinwu Jeong
- USC Institute for Genetic Medicine and Department of Ophthalmology, Keck School of Medicine of USC, University of Southern California, Los Angeles, California, United States of America
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Biophysical Methods to Investigate Intrinsically Disordered Proteins: Avoiding an “Elephant and Blind Men” Situation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:215-60. [DOI: 10.1007/978-3-319-20164-1_7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Merlotti A, Dantas E, Remes Lenicov F, Ceballos A, Jancic C, Varese A, Rubione J, Stover S, Geffner J, Sabatté J. Fucosylated clusterin in semen promotes the uptake of stress-damaged proteins by dendritic cells via DC-SIGN. Hum Reprod 2015; 30:1545-56. [PMID: 26003430 DOI: 10.1093/humrep/dev113] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 04/27/2015] [Indexed: 01/09/2023] Open
Abstract
STUDY QUESTION Could seminal plasma clusterin play a role in the uptake of stress-damaged proteins by dendritic cells? SUMMARY ANSWER Seminal plasma clusterin, but not serum clusterin, promotes the uptake of stress-damaged proteins by dendritic cells via DC-SIGN. WHAT IS KNOWN ALREADY Clusterin is one of the major extracellular chaperones. It interacts with a variety of stressed proteins to prevent their aggregation, guiding them for receptor-mediated endocytosis and intracellular degradation. The concentration of clusterin in semen is almost 20-fold higher than that found in serum, raising the question about the role of seminal plasma clusterin in reproduction. No previous studies have analyzed whether seminal plasma clusterin has chaperone activity. We have previously shown that seminal plasma clusterin, but not serum clusterin, expresses an extreme abundance of fucosylated glycans. These motifs enable seminal plasma clusterin to bind DC-SIGN with very high affinity. STUDY DESIGN, SIZE, DURATION In vitro experiments were performed to evaluate the ability of seminal plasma clusterin to inhibit the precipitation of stressed proteins, promoting their uptake by dendritic cells via DC-SIGN (a C-type lectin receptor selectively expressed on dendritic cells (DC)). Moreover, the ability of seminal plasma clusterin to modulate the phenotype and function of DCs was also assessed. PARTICIPANTS/MATERIALS, SETTING, METHODS Clusterin was purified from human semen and human serum. Catalase, bovine serum albumin, glutathione S-transferase, and normal human serum were stressed and the ability of seminal plasma clusterin to prevent the precipitation of these proteins, guiding them to DC-SIGN expressed by DCs, was evaluated using a fluorescence-activated cell sorter (FACS). Endocytosis of stressed proteins was analyzed by confocal microscopy and the ability of seminal plasma clusterin-treated DCs to stimulate the proliferation of CD25+FOXP3+CD4+ T cells was also evaluated by FACS. MAIN RESULTS AND THE ROLE OF CHANCE Seminal plasma clusterin interacts with stressed proteins, inhibits their aggregation (P < 0.01) and efficiently targets them to dendritic cells via DC-SIGN (P < 0.01). DCs efficiently endocytosed clusterin-client complexes and sorted them to degradative compartments involved in antigen processing and presentation. Moreover, we also found that the interaction of seminal plasma clusterin with DC-SIGN did not change the phenotype of DCs, but stimulates their ability to induce the expansion of CD25+FOXP3+CD4+ T lymphocytes (P < 0.05 versus control). LIMITATIONS, REASONS FOR CAUTION All the experiments were performed in vitro; hence the relevance of our observations should be validated in vivo. WIDER IMPLICATIONS OF THE FINDINGS Our results suggest that by inducing the endocytosis of stress-damaged proteins by DCs via DC-SIGN, seminal plasma clusterin might promote a tolerogenic response to male antigens, thereby contributing to female tolerance to seminal antigens. STUDY FUNDING/COMPETING INTERESTS The present research was supported by the Consejo Nacional de Investigaciones Científicas y Técnicas, the Buenos Aires University School of Medicine, and the Agencia Nacional de Promoción Científica y Tecnológica (Argentina). The authors have no conflicts of interest to declare.
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Affiliation(s)
- A Merlotti
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - E Dantas
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - F Remes Lenicov
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - A Ceballos
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - C Jancic
- Laboratorio de Inmunología Oncológica, Instituto de Medicina Experimental (IMEX), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Academia Nacional de Medicina, Ciudad Autónoma de Buenos Aires 1425, Argentina
| | - A Varese
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - J Rubione
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - S Stover
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - J Geffner
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
| | - J Sabatté
- Instituto de Investigaciones Biomédicas en Retrovirus y SIDA (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires 1121, Argentina
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Vassall KA, Jenkins AD, Bamm VV, Harauz G. Thermodynamic Analysis of the Disorder-to-α-Helical Transition of 18.5-kDa Myelin Basic Protein Reveals an Equilibrium Intermediate Representing the Most Compact Conformation. J Mol Biol 2015; 427:1977-92. [DOI: 10.1016/j.jmb.2015.03.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 03/11/2015] [Accepted: 03/17/2015] [Indexed: 10/23/2022]
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Forman-Kay JD, Mittag T. From sequence and forces to structure, function, and evolution of intrinsically disordered proteins. Structure 2014; 21:1492-9. [PMID: 24010708 DOI: 10.1016/j.str.2013.08.001] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 08/02/2013] [Accepted: 08/06/2013] [Indexed: 01/27/2023]
Abstract
Intrinsically disordered proteins (IDPs), which lack persistent structure, are a challenge to structural biology due to the inapplicability of standard methods for characterization of folded proteins as well as their deviation from the dominant structure/function paradigm. Their widespread presence and involvement in biological function, however, has spurred the growing acceptance of the importance of IDPs and the development of new tools for studying their structure, dynamics, and function. The interplay of folded and disordered domains or regions for function and the existence of a continuum of protein states with respect to conformational energetics, motional timescales, and compactness are shaping a unified understanding of structure-dynamics-disorder/function relationships. In the 20(th) anniversary of Structure, we provide a historical perspective on the investigation of IDPs and summarize the sequence features and physical forces that underlie their unique structural, functional, and evolutionary properties.
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Affiliation(s)
- Julie D Forman-Kay
- Molecular Structure and Function, Hospital for Sick Children, Toronto, ON, M5G 1X8, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.
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Chen P, Wang C, Ma X, Zhang Y, Liu Q, Qiu S, Liu Q, Tian J, Ni J. Direct Interaction of Selenoprotein R with Clusterin and Its Possible Role in Alzheimer's Disease. PLoS One 2013; 8:e66384. [PMID: 23805218 PMCID: PMC3689823 DOI: 10.1371/journal.pone.0066384] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 05/06/2013] [Indexed: 11/22/2022] Open
Abstract
Selenoprotein R (SelR) plays an important role in maintaining intracellular redox balance by reducing the R-form of methionine sulfoxide to methionine. As SelR is highly expressed in brain and closely related to Alzheimer′s disease (AD), its biological functions in human brain become a research focus. In this paper, the selenocysteine-coding TGA of SelR gene was mutated to cysteine-coding TGC and used to screen the human fetal brain cDNA library with a yeast two-hybrid system. Our results demonstrated that SelR interacts with clusterin (Clu), a chaperone protein. This protein interaction was further verified by fluorescence resonance energy transfer (FRET), coimmunoprecipitation (co-IP), and pull-down assays. The interacting domain of Clu was determined by co-IP to be a dynamic, molten globule structure spanning amino acids 315 to 381 with an amphipathic-helix. The interacting domain of SelR was investigated by gene manipulation, ligand replacement, protein over-expression, and enzyme activity measurement to be a tetrahedral complex consisting of a zinc ion binding with four Cys residues. Study on the mutual effect of SelR and Clu showed synergic property between the two proteins. Cell transfection with SelR gene increased the expression of Clu, while cell transfection with Clu promoted the enzyme activity of SelR. Co-overexpression of SelR and Clu in N2aSW cells, an AD model cell line, significantly decreased the level of intracellular reactive oxygen species. Furthermore, FRET and co-IP assays demonstrated that Clu interacted with β-amyloid peptide, a pathological protein of AD, which suggested a potential effect of SelR and Aβ with the aid of Clu. The interaction between SelR and Clu provides a novel avenue for further study on the mechanism of SelR in AD prevention.
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Affiliation(s)
- Ping Chen
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
- College of Optoelectronic Engineering, Shenzhen University, Shenzhen, P.R. China
| | - Chao Wang
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P.R. China
- University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, P.R. China
| | - Xiaojie Ma
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
| | - Yizhe Zhang
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
| | - Qing Liu
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
| | - Shi Qiu
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
| | - Qiong Liu
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
- * E-mail: (QL); (JN)
| | - Jing Tian
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
| | - Jiazuan Ni
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P.R. China
- College of life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
- * E-mail: (QL); (JN)
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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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Oldfield CJ, Xue B, Van YY, Ulrich EL, Markley JL, Dunker AK, Uversky VN. Utilization of protein intrinsic disorder knowledge in structural proteomics. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1834:487-98. [PMID: 23232152 DOI: 10.1016/j.bbapap.2012.12.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 12/02/2012] [Accepted: 12/03/2012] [Indexed: 12/01/2022]
Abstract
Intrinsically disordered proteins (IDPs) and proteins with long disordered regions are highly abundant in various proteomes. Despite their lack of well-defined ordered structure, these proteins and regions are frequently involved in crucial biological processes. Although in recent years these proteins have attracted the attention of many researchers, IDPs represent a significant challenge for structural characterization since these proteins can impact many of the processes in the structure determination pipeline. Here we investigate the effects of IDPs on the structure determination process and the utility of disorder prediction in selecting and improving proteins for structural characterization. Examination of the extent of intrinsic disorder in existing crystal structures found that relatively few protein crystal structures contain extensive regions of intrinsic disorder. Although intrinsic disorder is not the only cause of crystallization failures and many structured proteins cannot be crystallized, filtering out highly disordered proteins from structure-determination target lists is still likely to be cost effective. Therefore it is desirable to avoid highly disordered proteins from structure-determination target lists and we show that disorder prediction can be applied effectively to enrich structure determination pipelines with proteins more likely to yield crystal structures. For structural investigation of specific proteins, disorder prediction can be used to improve targets for structure determination. Finally, a framework for considering intrinsic disorder in the structure determination pipeline is proposed.
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Affiliation(s)
- Christopher J Oldfield
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
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Cholesterol: its regulation and role in central nervous system disorders. CHOLESTEROL 2012; 2012:292598. [PMID: 23119149 PMCID: PMC3483652 DOI: 10.1155/2012/292598] [Citation(s) in RCA: 193] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 09/03/2012] [Accepted: 09/10/2012] [Indexed: 02/08/2023]
Abstract
Cholesterol is a major constituent of the human brain, and the brain is the most cholesterol-rich organ. Numerous lipoprotein receptors and apolipoproteins are expressed in the brain. Cholesterol is tightly regulated between the major brain cells and is essential for normal brain development. The metabolism of brain cholesterol differs markedly from that of other tissues. Brain cholesterol is primarily derived by de novo synthesis and the blood brain barrier prevents the uptake of lipoprotein cholesterol from the circulation. Defects in cholesterol metabolism lead to structural and functional central nervous system diseases such as Smith-Lemli-Opitz syndrome, Niemann-Pick type C disease, and Alzheimer's disease. These diseases affect different metabolic pathways (cholesterol biosynthesis, lipid transport and lipoprotein assembly, apolipoproteins, lipoprotein receptors, and signaling molecules). We review the metabolic pathways of cholesterol in the CNS and its cell-specific and microdomain-specific interaction with other pathways such as the amyloid precursor protein and discuss potential treatment strategies as well as the effects of the widespread use of LDL cholesterol-lowering drugs on brain functions.
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Ahmed MAM, De Avila M, Polverini E, Bessonov K, Bamm VV, Harauz G. Solution nuclear magnetic resonance structure and molecular dynamics simulations of a murine 18.5 kDa myelin basic protein segment (S72-S107) in association with dodecylphosphocholine micelles. Biochemistry 2012; 51:7475-87. [PMID: 22947219 DOI: 10.1021/bi300998x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The 18.5 kDa myelin basic protein (MBP), the most abundant splice isoform in adult mammalian myelin, is a multifunctional, intrinsically disordered protein involved in the development and compaction of the myelin sheath in the central nervous system. A highly conserved central segment comprises a membrane-anchoring amphipathic α-helix followed by a proline-rich segment that represents a ligand for SH3 domain-containing proteins. Here, we have determined using solution nuclear magnetic resonance spectroscopy the structure of a 36-residue peptide fragment of MBP (murine 18.5 kDa residues S72-S107, denoted the α2-peptide) comprising these two structural motifs, in association with dodecylphosphocholine (DPC) micelles. The structure was calculated using CS-ROSETTA (version 1.01) because the nuclear Overhauser effect restraints were insufficient for this protein. The experimental studies were complemented by molecular dynamics simulations of a corresponding 24-residue peptide fragment (murine 18.5 kDa residues E80-G103, denoted the MD-peptide), also in association with a DPC micelle in silico. The experimental and theoretical results agreed well with one another, despite the independence of the starting structures and analyses, both showing membrane association via the amphipathic α-helix, and a sharp bend in the vicinity of the Pro93 residue (murine 18.5 kDa sequence numbering). Overall, the conformations elucidated here show how the SH3 ligand is presented to the cytoplasm for interaction with SH3 domain-containing proteins such as Fyn and contribute to our understanding of myelin architecture at the molecular level.
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Affiliation(s)
- Mumdooh A M Ahmed
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
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Roles of Extracellular Chaperones in Amyloidosis. J Mol Biol 2012; 421:499-516. [DOI: 10.1016/j.jmb.2012.01.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 01/02/2012] [Accepted: 01/03/2012] [Indexed: 01/24/2023]
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Härd T, Lendel C. Inhibition of amyloid formation. J Mol Biol 2012; 421:441-65. [PMID: 22244855 DOI: 10.1016/j.jmb.2011.12.062] [Citation(s) in RCA: 215] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 12/28/2011] [Accepted: 12/29/2011] [Indexed: 12/26/2022]
Abstract
Amyloid is aggregated protein in the form of insoluble fibrils. Amyloid deposition in human tissue-amyloidosis-is associated with a number of diseases including all common dementias and type II diabetes. Considerable progress has been made to understand the mechanisms leading to amyloid formation. It is, however, not yet clear by which mechanisms amyloid and protein aggregates formed on the path to amyloid are cytotoxic. Strategies to prevent protein aggregation and amyloid formation are nevertheless, in many cases, promising and even successful. This review covers research on intervention of amyloidosis and highlights several examples of how inhibition of protein aggregation and amyloid formation has been achieved in practice. For instance, rational design can provide drugs that stabilize a native folded state of a protein, protein engineering can provide new binding proteins that sequester monomeric peptides from aggregation, small molecules and peptides can be designed to block aggregation or direct it into non-cytotoxic paths, and monoclonal antibodies have been developed for therapies towards neurodegenerative diseases based on inhibition of amyloid formation and clearance.
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Affiliation(s)
- Torleif Härd
- Department of Molecular Biology, Swedish University of Agricultural Sciences, SE-751 24 Uppsala, Sweden.
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Binding stoichiometry and affinity of fluorescent dyes to proteins in different structural states. Methods Mol Biol 2012; 895:441-60. [PMID: 22760333 DOI: 10.1007/978-1-61779-927-3_26] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Protocol of determination of binding stoichiometry and affinity of fluorescent dyes with proteins in different structural states is proposed. The proposed approach is based on the spectrophotometric determination of concentrations of dye bound to protein and free dye in solutions prepared by equilibrium microdialysis. This technique allows also determining spectral properties of the bound dyes. The restrictions of the use of dye fluorescence intensity for characterization of its interaction with the target protein are discussed. It is shown that the dependence of the dye fluorescence intensity on its optical density together with the data on its binding parameter can give information about the dye fluorescence quantum yield. All procedures are illustrated by interaction of 8-anilino-1-naphthalenesulfonate (ANS) with bovine serum albumin.
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Materia S, Cater MA, Klomp LWJ, Mercer JFB, La Fontaine S. Clusterin and COMMD1 independently regulate degradation of the mammalian copper ATPases ATP7A and ATP7B. J Biol Chem 2011; 287:2485-99. [PMID: 22130675 DOI: 10.1074/jbc.m111.302216] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
ATP7A and ATP7B are copper-transporting P(1B)-type ATPases (Cu-ATPases) that are critical for regulating intracellular copper homeostasis. Mutations in the genes encoding ATP7A and ATP7B lead to copper deficiency and copper toxicity disorders, Menkes and Wilson diseases, respectively. Clusterin and COMMD1 were previously identified as interacting partners of these Cu-ATPases. In this study, we confirmed that clusterin and COMMD1 interact to down-regulate both ATP7A and ATP7B. Overexpression and knockdown of clusterin/COMMD1 decreased and increased, respectively, endogenous levels of ATP7A and ATP7B, consistent with a role in facilitating Cu-ATPase degradation. We demonstrate that whereas the clusterin/ATP7B interaction was enhanced by oxidative stress or mutation of ATP7B, the COMMD1/ATP7B interaction did not change under oxidative stress conditions, and only increased with ATP7B mutations that led to its misfolding. Clusterin and COMMD1 facilitated the degradation of ATP7B containing the same Wilson disease-causing C-terminal mutations via different degradation pathways, clusterin via the lysosomal pathway and COMMD1 via the proteasomal pathway. Furthermore, endogenous ATP7B existed in a complex with clusterin and COMMD1, but these interactions were neither competitive nor cooperative and occurred independently of each other. Together these data indicate that clusterin and COMMD1 represent alternative and independent systems regulating Cu-ATPase quality control, and consequently contributing to the maintenance of copper homeostasis.
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Affiliation(s)
- Stephanie Materia
- Strategic Research Centre for Molecular and Medical Research, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia
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Polverini E, Coll EP, Tieleman DP, Harauz G. Conformational choreography of a molecular switch region in myelin basic protein—Molecular dynamics shows induced folding and secondary structure type conversion upon threonyl phosphorylation in both aqueous and membrane-associated environments. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:674-83. [DOI: 10.1016/j.bbamem.2010.11.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Revised: 11/10/2010] [Accepted: 11/23/2010] [Indexed: 12/12/2022]
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Cerf E, Gustot A, Goormaghtigh E, Ruysschaert JM, Raussens V. High ability of apolipoprotein E4 to stabilize amyloid-β peptide oligomers, the pathological entities responsible for Alzheimer's disease. FASEB J 2011; 25:1585-95. [PMID: 21266538 DOI: 10.1096/fj.10-175976] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nowadays, the emerging role of amyloid-β peptide (Aβ) oligomers in Alzheimer's disease (AD) is widely accepted, putting aside the old idea that fibrils are the primary entities responsible for the onset of the disease. Besides, carrying the E4 isoform of apolipoprotein E (apoE) represents the highest risk of developing AD. Nevertheless, the involvement of apoE4 in AD remains confusing. The goal of this study was to bring new insights into the role of apoE4 in Aβ aggregation. We used infrared spectroscopy, thioflavin T fluorescence, and Western blots to evaluate the influence of apoE isoforms on Aβ aggregation in vitro. Comparing Aβ controls with Aβ incubated either with the apoE3 or apoE4 isoform, we report a 30% reduction of the Aβ fibrillar content, whereas the oligomeric content is 2 times higher on incubation with the pathological isoform apoE4. ApoE4 would bind and block Aβ in its oligomeric conformation, inhibiting further formation of less toxic fibrillar forms of Aβ. While previous studies mostly correlated E4 with fibrils, our report underlines a link between apoE4 and Aβ oligomers and therefore reconciles apoE4 with the new amyloid cascade hypothesis. Our observations suggest that apoE4 strongly stabilizes Aβ oligomers, the pathological species responsible for Alzheimer's disease.
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Affiliation(s)
- Emilie Cerf
- Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université Libre de Bruxelles, Brussels, Belgium
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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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Greene MJ, Sam F, Soo Hoo PT, Patel RS, Seldin DC, Connors LH. Evidence for a functional role of the molecular chaperone clusterin in amyloidotic cardiomyopathy. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 178:61-8. [PMID: 21224044 DOI: 10.1016/j.ajpath.2010.11.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 09/02/2010] [Accepted: 09/30/2010] [Indexed: 01/20/2023]
Abstract
Molecular chaperones, including the extracellular protein clusterin (CLU), play a significant role in maintaining proteostasis; they have a unique capacity to bind and stabilize non-native protein conformations, prevent aggregation, and keep proteins in a soluble folding-competent state. In this study, we investigated amyloid-infiltrated cardiac tissue for the presence of CLU and measured serum levels of CLU in patients with and without amyloidotic cardiomyopathy (CMP). Cardiac tissues containing amyloid deposits composed of either transthyretin (TTR) or Ig light chain from nine patients with amyloidotic CMP were examined for the presence of CLU using immunohistochemical techniques. CLU staining coincided with the extracellular myocardial amyloid deposits in tissues from patients with familial TTR, senile systemic, and Ig light chain amyloidosis. The association of CLU with cardiac amyloid deposits was confirmed by immunogold electron microscopy. Serum concentrations of CLU were measured in familial TTR, senile systemic, and Ig light chain amyloidosis patient groups and compared with both age-matched healthy controls and with patients with CMP unrelated to amyloid disease. Subset analysis of disease cohorts, based on cardiac involvement, indicated that decreased serum CLU concentrations were associated with amyloidotic CMP. Taken together, these results suggest that CLU may play a pathogenetic role in TTR and Ig light chain amyloidoses and amyloidotic CMP.
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Affiliation(s)
- Michael J Greene
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts, USA
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Siltberg-Liberles J. Evolution of structurally disordered proteins promotes neostructuralization. Mol Biol Evol 2010; 28:59-62. [PMID: 21037204 DOI: 10.1093/molbev/msq291] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Protein structure is generally more conserved than sequence, but for regions that can adopt different structures in different environments, does this hold true? Understanding how structurally disordered regions evolve altered secondary structure element propensities as well as conformational flexibility among paralogs are fundamental questions for our understanding of protein structural evolution. We have investigated the evolutionary dynamics of structural disorder in protein families containing both orthologs and paralogs using phylogenetic tree reconstruction, protein structure disorder prediction, and secondary structure prediction in order to shed light upon these questions. Our results indicate that the extent and location of structurally disordered regions are not universally conserved. As structurally disordered regions often have high conformational flexibility, this is likely to have an effect on how protein structure evolves as spatially altered conformational flexibility can also change the secondary structure propensities for homologous regions in a protein family.
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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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Flanagan L, Whyte L, Chatterjee N, Tenniswood M. Effects of clusterin over-expression on metastatic progression and therapy in breast cancer. BMC Cancer 2010; 10:107. [PMID: 20307318 PMCID: PMC2856549 DOI: 10.1186/1471-2407-10-107] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2009] [Accepted: 03/22/2010] [Indexed: 12/22/2022] Open
Abstract
Background Clusterin is a secreted glycoprotein that is upregulated in a variety of cell lines in response to stress, and enhances cell survival. A second nuclear isoform of clusterin that is associated with cell death has also been identified. The aim of this study was to determine the role(s) of the secretory isoform in breast tumor progression and metastasis. Methods To investigate the role of secretory clusterin in the biology of breast cancer tumor growth and resistance to therapy we have engineered an MCF-7 cell line (MCF-7CLU) that over-expresses clusterin. We have measured the in vitro effects of clusterin over-expression on cell cycle, cell death, and sensitivity to TNFalpha and tamoxifen. Using an orthotopic model of breast cancer, we have also determined the effects of over-expression of clusterin on tumor growth and metastatic progression. Results In vitro, over-expression of secretory clusterin alters the cell cycle kinetics and decreases the rate of cell death, resulting in the enhancement of cell growth. Over-expression of secretory clusterin also blocks the TNFalpha-mediated induction of p21 and abrogates the cleavage of Bax to t-Bax, rendering the MCF-7CLU cells significantly more resistant to the cytokine than the parental cells. Orthotopic primary tumors derived from MCF-7CLU cells grow significantly more rapidly than tumors derived from parental MCF-7 cells and, unlike the parental cells, metastasize frequently to the lungs. Conclusions These data suggest that secretory clusterin, which is frequently up-regulated in breast cancers by common therapies, including anti-estrogens, may play a significant role in tumor growth, metastatic progression and subsequent drug resistance in surviving cells.
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Affiliation(s)
- Louise Flanagan
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
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Kelly BA, Harrison I, McKnight A, Dobson CB. Anti-infective activity of apolipoprotein domain derived peptides in vitro: identification of novel antimicrobial peptides related to apolipoprotein B with anti-HIV activity. BMC Immunol 2010; 11:13. [PMID: 20298574 PMCID: PMC2855520 DOI: 10.1186/1471-2172-11-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 03/18/2010] [Indexed: 11/10/2022] Open
Abstract
Background Previous reports have shown that peptides derived from the apolipoprotein E receptor binding region and the amphipathic α-helical domains of apolipoprotein AI have broad anti-infective activity and antiviral activity respectively. Lipoproteins and viruses share a similar cell biological niche, being of overlapping size and displaying similar interactions with mammalian cells and receptors, which may have led to other antiviral sequences arising within apolipoproteins, in addition to those previously reported. We therefore designed a series of peptides based around either apolipoprotein receptor binding regions, or amphipathic α-helical domains, and tested these for antiviral and antibacterial activity. Results Of the nineteen new peptides tested, seven showed some anti-infective activity, with two of these being derived from two apolipoproteins not previously used to derive anti-infective sequences. Apolipoprotein J (151-170) - based on a predicted amphipathic alpha-helical domain from apolipoprotein J - had measurable anti-HSV1 activity, as did apolipoprotein B (3359-3367) dp (apoBdp), the latter being derived from the LDL receptor binding domain B of apolipoprotein B. The more active peptide - apoBdp - showed similarity to the previously reported apoE derived anti-infective peptide, and further modification of the apoBdp sequence to align the charge distribution more closely to that of apoEdp or to introduce aromatic residues resulted in increased breadth and potency of activity. The most active peptide of this type showed similar potent anti-HIV activity, comparable to that we previously reported for the apoE derived peptide apoEdpL-W. Conclusions These data suggest that further antimicrobial peptides may be obtained using human apolipoprotein sequences, selecting regions with either amphipathic α-helical structure, or those linked to receptor-binding regions. The finding that an amphipathic α-helical region of apolipoprotein J has antiviral activity comparable with that for the previously reported apolipoprotein AI derived peptide 18A, suggests that full-length apolipoprotein J may also have such activity, as has been reported for full-length apolipoprotein AI. Although the strength of the anti-infective activity of the sequences identified was limited, this could be increased substantially by developing related mutant peptides. Indeed the apolipoprotein B-derived peptide mutants uncovered by the present study may have utility as HIV therapeutics or microbicides.
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Affiliation(s)
- Bridie A Kelly
- Faculty of Life Sciences, Stopford Building, The University of Manchester, Manchester, M13 9PT, UK
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