1
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Zhang B, Boyd SD, Zhabilov D, Ullrich M, Blackburn NJ, Winkler DD. Pathogenic R 163W Variant of the Copper Chaperone for Sod1 (Ccs) Functions as an Anti-chaperone. Biochemistry 2024; 63:2051-2062. [PMID: 39099176 DOI: 10.1021/acs.biochem.4c00223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
The copper chaperone for Sod1 (Ccs) is a metallochaperone that plays a multifaceted role in the maturation of Cu,Zn superoxide dismutase (Sod1). The Ccs mutation R163W was identified in an infant with fatal neurological abnormalities. Based on a comprehensive structural and functional analysis, we developed the first data-driven model for R163W-related pathogenic phenotypes. The work here confirms previous findings that the substitution of arginine with tryptophan at this site, which is located adjacent to a conserved Zn binding site, creates an unstable Zn-deficient protein that loses its ability to efficiently activate Sod1. Intriguingly, R163W Ccs can reduce copper (i.e., Cu(II) → Cu(I)) bound in its Sod1-like domain (D2), and this novel redox event is accompanied by disulfide bond formation. The loss of Zn binding, along with the unusual ability to bind copper in D2, diverts R163W Ccs toward aggregation. The remarkably high affinity of D2 Cu(I) binding converts R163W from a Cu chaperone to a Cu scavenger that accelerates Sod1 deactivation (i.e., an Anti-chaperone). Overall, these findings present a first-of-its-kind molecular mechanism for Ccs dysfunction that leads to pathogenesis in humans.
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Affiliation(s)
- Bei Zhang
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75083, United States
| | - Stefanie D Boyd
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75083, United States
| | - Dannie Zhabilov
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75083, United States
| | - Morgan Ullrich
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75083, United States
| | - Ninian J Blackburn
- Department of Chemical Physiology and Biochemistry, Oregon Health and Sciences University, Portland, Oregon 97239, United States
| | - Duane D Winkler
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, Texas 75083, United States
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2
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Lambert-Smith IA, Shephard VK, McAlary L, Yerbury JJ, Saunders DN. High-content analysis of proteostasis capacity in cellular models of amyotrophic lateral sclerosis (ALS). Sci Rep 2024; 14:13844. [PMID: 38879591 PMCID: PMC11180180 DOI: 10.1038/s41598-024-64366-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 06/07/2024] [Indexed: 06/19/2024] Open
Abstract
Disrupted proteome homeostasis (proteostasis) in amyotrophic lateral sclerosis (ALS) has been a major focus of research in the past two decades. However, the proteostasis processes that become disturbed in ALS are not fully understood. Obtaining more detailed knowledge of proteostasis disruption in association with different ALS-causing mutations will improve our understanding of ALS pathophysiology and may identify novel therapeutic targets and strategies for ALS patients. Here we describe the development and use of a novel high-content analysis (HCA) assay to investigate proteostasis disturbances caused by the expression of several ALS-causing gene variants. This assay involves the use of conformationally-destabilised mutants of firefly luciferase (Fluc) to examine protein folding/re-folding capacity in NSC-34 cells expressing ALS-associated mutations in the genes encoding superoxide dismutase-1 (SOD1A4V) and cyclin F (CCNFS621G). We demonstrate that these Fluc isoforms can be used in high-throughput format to report on reductions in the activity of the chaperone network that result from the expression of SOD1A4V, providing multiplexed information at single-cell resolution. In addition to SOD1A4V and CCNFS621G, NSC-34 models of ALS-associated TDP-43, FUS, UBQLN2, OPTN, VCP and VAPB mutants were generated that could be screened using this assay in future work. For ALS-associated mutant proteins that do cause reductions in protein quality control capacity, such as SOD1A4V, this assay has potential to be applied in drug screening studies to identify candidate compounds that can ameliorate this deficiency.
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Affiliation(s)
- Isabella A Lambert-Smith
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia.
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia.
| | - Victoria K Shephard
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Luke McAlary
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Darren N Saunders
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, 2522, Australia.
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3
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Mansuri S, Jain A, Singh R, Rawat S, Mondal D, Raychaudhuri S. Widespread nuclear lamina injuries defeat proteostatic purposes of α-synuclein amyloid inclusions. J Cell Sci 2024; 137:jcs261935. [PMID: 38477372 DOI: 10.1242/jcs.261935] [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: 12/31/2023] [Accepted: 03/03/2024] [Indexed: 03/14/2024] Open
Abstract
Biogenesis of inclusion bodies (IBs) facilitates protein quality control (PQC). Canonical aggresomes execute degradation of misfolded proteins while non-degradable amyloids sequester into insoluble protein deposits. Lewy bodies (LBs) are filamentous amyloid inclusions of α-synuclein, but PQC benefits and drawbacks associated with LB-like IBs remain underexplored. Here, we report that crosstalk between filamentous LB-like IBs and aggresome-like IBs of α-synuclein (Syn-aggresomes) buffer the load, aggregation state, and turnover of the amyloidogenic protein in mouse primary neurons and HEK293T cells. Filamentous LB-like IBs possess unorthodox PQC capacities of self-quarantining α-synuclein amyloids and being degradable upon receding fresh amyloidogenesis. Syn-aggresomes equilibrate biogenesis of filamentous LB-like IBs by facilitating spontaneous degradation of α-synuclein and conditional turnover of disintegrated α-synuclein amyloids. Thus, both types of IB primarily contribute to PQC. Incidentally, the overgrown perinuclear LB-like IBs become degenerative once these are misidentified by BICD2, a cargo-adapter for the cytosolic motor-protein dynein. Microscopy indicates that microtubules surrounding the perinuclear filamentous inclusions are also distorted, misbalancing the cytoskeleton-nucleoskeleton tension leading to widespread lamina injuries. Together, nucleocytoplasmic mixing, DNA damage, and deregulated transcription of stress chaperones defeat the proteostatic purposes of the filamentous amyloids of α-synuclein.
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Affiliation(s)
- Shemin Mansuri
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
| | - Aanchal Jain
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Richa Singh
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
| | - Shivali Rawat
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
| | - Debodyuti Mondal
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
| | - Swasti Raychaudhuri
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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4
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Carter Z, Creamer D, Kouvidi A, Grant CM. Sequestrase chaperones protect against oxidative stress-induced protein aggregation and [PSI+] prion formation. PLoS Genet 2024; 20:e1011194. [PMID: 38422160 DOI: 10.1371/journal.pgen.1011194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/12/2024] [Accepted: 02/20/2024] [Indexed: 03/02/2024] Open
Abstract
Misfolded proteins are usually refolded to their functional conformations or degraded by quality control mechanisms. When misfolded proteins evade quality control, they can be sequestered to specific sites within cells to prevent the potential dysfunction and toxicity that arises from protein aggregation. Btn2 and Hsp42 are compartment-specific sequestrases that play key roles in the assembly of these deposition sites. Their exact intracellular functions and substrates are not well defined, particularly since heat stress sensitivity is not observed in deletion mutants. We show here that Btn2 and Hsp42 are required for tolerance to oxidative stress conditions induced by exposure to hydrogen peroxide. Btn2 and Hsp42 act to sequester oxidized proteins into defined PQC sites following ROS exposure and their absence leads to an accumulation of protein aggregates. The toxicity of protein aggregate accumulation causes oxidant sensitivity in btn2 hsp42 sequestrase mutants since overexpression of the Hsp104 disaggregase rescues oxidant tolerance. We have identified the Sup35 translation termination factor as an in vivo sequestrase substrate and show that Btn2 and Hsp42 act to suppress oxidant-induced formation of the yeast [PSI+] prion, which is the amyloid form of Sup35. [PSI+] prion formation in sequestrase mutants does not require IPOD (insoluble protein deposit) localization which is the site where amyloids are thought to undergo fragmentation and seeding to propagate their heritable prion form. Instead, both amorphous and amyloid Sup35 aggregates are increased in btn2 hsp42 mutants consistent with the idea that prion formation occurs at multiple intracellular sites during oxidative stress conditions in the absence of sequestrase activity. Taken together, our data identify protein sequestration as a key antioxidant defence mechanism that functions to mitigate the damaging consequences of protein oxidation-induced aggregation.
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Affiliation(s)
- Zorana Carter
- Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, United Kingdom
| | - Declan Creamer
- Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, United Kingdom
| | - Aikaterini Kouvidi
- Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, United Kingdom
| | - Chris M Grant
- Faculty of Biology, Medicine and Health, School of Biological Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, United Kingdom
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5
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Weerawarna PM, Schiefer IT, Soares P, Fox S, Morimoto RI, Melani RD, Kelleher NL, Luan CH, Silverman RB. Target Identification of a Class of Pyrazolone Protein Aggregation Inhibitor Therapeutics for Amyotrophic Lateral Sclerosis. ACS CENTRAL SCIENCE 2024; 10:87-103. [PMID: 38292603 PMCID: PMC10823514 DOI: 10.1021/acscentsci.3c00213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 11/01/2023] [Accepted: 11/27/2023] [Indexed: 02/01/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with no cure, and current treatment options are very limited. Previously, we performed a high-throughput screen to identify small molecules that inhibit protein aggregation caused by a mutation in the gene that encodes superoxide dismutase 1 (SOD1), which is responsible for about 25% of familial ALS. This resulted in three hit series of compounds that were optimized over several years to give three compounds that were highly active in a mutant SOD1 ALS model. Here we identify the target of two of the active compounds (6 and 7) with the use of photoaffinity labeling, chemical biology reporters, affinity purification, proteomic analysis, and fluorescent/cellular thermal shift assays. Evidence is provided to demonstrate that these two pyrazolone compounds directly interact with 14-3-3-E and 14-3-3-Q isoforms, which have chaperone activity and are known to interact with mutant SOD1G93A aggregates and become insoluble in the subcellular JUNQ compartment, leading to apoptosis. Because protein aggregation is the hallmark of all neurodegenerative diseases, knowledge of the target compounds that inhibit protein aggregation allows for the design of more effective molecules for the treatment of ALS and possibly other neurodegenerative diseases.
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Affiliation(s)
- Pathum M. Weerawarna
- Department
of Chemistry, Chemistry of Life Processes Institute, Center for Developmental
Therapeutics, Northwestern University, Evanston, Illinois 60208, United States
| | - Isaac T. Schiefer
- Department
of Chemistry, Chemistry of Life Processes Institute, Center for Developmental
Therapeutics, Northwestern University, Evanston, Illinois 60208, United States
| | - Pedro Soares
- Department
of Chemistry, Chemistry of Life Processes Institute, Center for Developmental
Therapeutics, Northwestern University, Evanston, Illinois 60208, United States
| | - Susan Fox
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Richard I. Morimoto
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Rafael D. Melani
- Department
of Chemistry and Proteomics Center of Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Neil L. Kelleher
- Department
of Chemistry, Chemistry of Life Processes Institute, Center for Developmental
Therapeutics, Northwestern University, Evanston, Illinois 60208, United States
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
- Proteomics
Center of Excellence, Northwestern University, Evanston, Illinois 60208, United States
| | - Chi-Hao Luan
- High
Throughput
Analysis Laboratory, Chemistry of Life Processes Institute, and Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
| | - Richard B. Silverman
- Department
of Chemistry, Chemistry of Life Processes Institute, Center for Developmental
Therapeutics, Northwestern University, Evanston, Illinois 60208, United States
- Department
of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, United States
- Department
of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, United States
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6
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Sontag EM, Morales-Polanco F, Chen JH, McDermott G, Dolan PT, Gestaut D, Le Gros MA, Larabell C, Frydman J. Nuclear and cytoplasmic spatial protein quality control is coordinated by nuclear-vacuolar junctions and perinuclear ESCRT. Nat Cell Biol 2023; 25:699-713. [PMID: 37081164 DOI: 10.1038/s41556-023-01128-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 03/14/2023] [Indexed: 04/22/2023]
Abstract
Effective protein quality control (PQC), essential for cellular health, relies on spatial sequestration of misfolded proteins into defined inclusions. Here we reveal the coordination of nuclear and cytoplasmic spatial PQC. Cytoplasmic misfolded proteins concentrate in a cytoplasmic juxtanuclear quality control compartment, while nuclear misfolded proteins sequester into an intranuclear quality control compartment (INQ). Particle tracking reveals that INQ and the juxtanuclear quality control compartment converge to face each other across the nuclear envelope at a site proximal to the nuclear-vacuolar junction marked by perinuclear ESCRT-II/III protein Chm7. Strikingly, convergence at nuclear-vacuolar junction contacts facilitates VPS4-dependent vacuolar clearance of misfolded cytoplasmic and nuclear proteins, the latter entailing extrusion of nuclear INQ into the vacuole. Finding that nuclear-vacuolar contact sites are cellular hubs of spatial PQC to facilitate vacuolar clearance of nuclear and cytoplasmic inclusions highlights the role of cellular architecture in proteostasis maintenance.
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Affiliation(s)
- Emily M Sontag
- Department of Biology, Stanford University, Stanford, CA, USA.
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.
| | | | - Jian-Hua Chen
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Gerry McDermott
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Patrick T Dolan
- Department of Biology, Stanford University, Stanford, CA, USA
- Quantitative Virology and Evolution Unit, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Daniel Gestaut
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Mark A Le Gros
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Carolyn Larabell
- Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, CA, USA.
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7
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Jung KH, Sun J, Hsiung CH, Lance Lian X, Liu Y, Zhang X. Nuclear bodies protect phase separated proteins from degradation in stressed proteome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.19.537522. [PMID: 37131610 PMCID: PMC10153235 DOI: 10.1101/2023.04.19.537522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
RNA-binding proteins (RBPs) containing intrinsically disordered domains undergo liquid-liquid phase separation to form nuclear bodies under stress conditions. This process is also connected to the misfolding and aggregation of RBPs, which are associated with a series of neurodegenerative diseases. However, it remains elusive how folding states of RBPs changes upon the formation and maturation of nuclear bodies. Here, we describe SNAP-tag based imaging methods to visualize the folding states of RBPs in live cells via time-resolved quantitative microscopic analyses of their micropolarity and microviscosity. Using these imaging methods in conjunction with immunofluorescence imaging, we demonstrate that RBPs, represented by TDP-43, initially enters the PML nuclear bodies in its native state upon transient proteostasis stress, albeit it begins to misfolded during prolonged stress. Furthermore, we show that heat shock protein 70 co-enters the PML nuclear bodies to prevent the degradation of TDP-43 from the proteotoxic stress, thus revealing a previously unappreciated protective role of the PML nuclear bodies in the prevention of stress-induced degradation of TDP-43. In summary, our imaging methods described in the manuscript, for the first time, reveal the folding states of RBPs, which were previously challenging to study with conventional methods in nuclear bodies of live cells. This study uncovers the mechanistic correlations between the folding states of a protein and functions of nuclear bodies, in particular PML bodies. We envision that the imaging methods can be generally applied to elucidating the structural aspects of other proteins that exhibit granular structures under biological stimulus.
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Affiliation(s)
- Kwan Ho Jung
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Jiarui Sun
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Chia-Heng Hsiung
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
- Present address: Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou 310030, Zhejiang Province, China; Westlake Laboratory of Life Sciences and Biomedicine; 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Xiaojun Lance Lian
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
| | - Yu Liu
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, China
| | - Xin Zhang
- Department of Chemistry, Department of Biochemistry and Molecular Biology, The Huck Institute of Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
- Present address: Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou 310030, Zhejiang Province, China; Westlake Laboratory of Life Sciences and Biomedicine; 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
- Department of Biomedical Engineering, The Huck Institute of Life Sciences, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, 16802, United States
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8
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Lim SM, Nahm M, Kim SH. Proteostasis and Ribostasis Impairment as Common Cell Death Mechanisms in Neurodegenerative Diseases. J Clin Neurol 2023; 19:101-114. [PMID: 36854331 PMCID: PMC9982182 DOI: 10.3988/jcn.2022.0379] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/07/2022] [Accepted: 12/07/2022] [Indexed: 03/02/2023] Open
Abstract
The cellular homeostasis of proteins (proteostasis) and RNA metabolism (ribostasis) are essential for maintaining both the structure and function of the brain. However, aging, cellular stress conditions, and genetic contributions cause disturbances in proteostasis and ribostasis that lead to protein misfolding, insoluble aggregate deposition, and abnormal ribonucleoprotein granule dynamics. In addition to neurons being primarily postmitotic, nondividing cells, they are more susceptible to the persistent accumulation of abnormal aggregates. Indeed, defects associated with the failure to maintain proteostasis and ribostasis are common pathogenic components of age-related neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Furthermore, the neuronal deposition of misfolded and aggregated proteins can cause both increased toxicity and impaired physiological function, which lead to neuronal dysfunction and cell death. There is recent evidence that irreversible liquid-liquid phase separation (LLPS) is responsible for the pathogenic aggregate formation of disease-related proteins, including tau, α-synuclein, and RNA-binding proteins, including transactive response DNA-binding protein 43, fused in sarcoma, and heterogeneous nuclear ribonucleoprotein A1. Investigations of LLPS and its control therefore suggest that chaperone/disaggregase, which reverse protein aggregation, are valuable therapeutic targets for effective treatments for neurological diseases. Here we review and discuss recent studies to highlight the importance of understanding the common cell death mechanisms of proteostasis and ribostasis in neurodegenerative diseases.
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Affiliation(s)
- Su Min Lim
- Cell Therapy Center and Department of Neurology, College of Medicine, Hanyang University, Seoul, Korea
| | - Minyeop Nahm
- Dementia Research Group, Korea Brain Research Institute, Daegu, Korea
| | - Seung Hyun Kim
- Cell Therapy Center and Department of Neurology, College of Medicine, Hanyang University, Seoul, Korea.
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9
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A liquid-to-solid phase transition of Cu/Zn superoxide dismutase 1 initiated by oxidation and disease mutation. J Biol Chem 2023; 299:102857. [PMID: 36592929 PMCID: PMC9898760 DOI: 10.1016/j.jbc.2022.102857] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 12/17/2022] [Accepted: 12/19/2022] [Indexed: 01/01/2023] Open
Abstract
Cu/Zn superoxide dismutase 1 (SOD1) has a high propensity to misfold and form abnormal aggregates when it is subjected to oxidative stress or carries mutations associated with amyotrophic lateral sclerosis. However, the transition from functional soluble SOD1 protein to aggregated SOD1 protein is not completely clear. Here, we propose that liquid-liquid phase separation (LLPS) represents a biophysical process that converts soluble SOD1 into aggregated SOD1. We determined that SOD1 undergoes LLPS in vitro and cells under oxidative stress. Abnormal oxidation of SOD1 induces maturation of droplets formed by LLPS, eventually leading to protein aggregation and fibrosis, and involves residues Cys111 and Trp32. Additionally, we found that pathological mutations in SOD1 associated with ALS alter the morphology and material state of the droplets and promote the transformation of SOD1 to solid-like oligomers which are toxic to nerve cells. Furthermore, the fibrous aggregates formed by both pathways have a concentration-dependent toxicity effect on nerve cells. Thus, these combined results strongly indicate that LLPS may play a major role in pathological SOD1 aggregation, contributing to pathogenesis in ALS.
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10
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Molecular Investigations of Protein Aggregation in the Pathogenesis of Amyotrophic Lateral Sclerosis. Int J Mol Sci 2022; 24:ijms24010704. [PMID: 36614144 PMCID: PMC9820914 DOI: 10.3390/ijms24010704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating progressive neurodegenerative disorder characterized by selective loss of lower and upper motor neurons (MNs) in the brain and spinal cord, resulting in paralysis and eventually death due to respiratory insufficiency. Although the fundamental physiological mechanisms underlying ALS are not completely understood, the key neuropathological hallmarks of ALS pathology are the aggregation and accumulation of ubiquitinated protein inclusions within the cytoplasm of degenerating MNs. Herein, we discuss recent insights into the molecular mechanisms that lead to the accumulation of protein aggregates in ALS. This will contribute to a better understanding of the pathophysiology of the disease and may open novel avenues for the development of therapeutic strategies.
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11
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Baek Y, Woo TG, Ahn J, Lee D, Kwon Y, Park BJ, Ha NC. Structural analysis of the overoxidized Cu/Zn-superoxide dismutase in ROS-induced ALS filament formation. Commun Biol 2022; 5:1085. [PMID: 36224351 PMCID: PMC9556535 DOI: 10.1038/s42003-022-04017-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 09/21/2022] [Indexed: 11/09/2022] Open
Abstract
Eukaryotic Cu, Zn-superoxide dismutase (SOD1) is primarily responsible for cytotoxic filament formation in amyotrophic lateral sclerosis (ALS) neurons. Two cysteine residues in SOD1 form an intramolecular disulfide bond. This study aims to explore the molecular mechanism of SOD1 filament formation by cysteine overoxidation in sporadic ALS (sALS). In this study, we determined the crystal structure of the double mutant (C57D/C146D) SOD1 that mimics the overoxidation of the disulfide-forming cysteine residues. The structure revealed the open and relaxed conformation of loop IV containing the mutated Asp57. The double mutant SOD1 produced more contagious filaments than wild-type protein, promoting filament formation of the wild-type SOD1 proteins. Importantly, we further found that HOCl treatment to the wild-type SOD1 proteins facilitated their filament formation. We propose a feasible mechanism for SOD1 filament formation in ALS from the wild-type SOD1, suggesting that overoxidized SOD1 is a triggering factor of sALS. Our findings extend our understanding of other neurodegenerative disorders associated with ROS stresses at the molecular level. Characterization of the structure of an overoxidation-mimicking double mutant of superoxide dismutase SOD1 shows the production of more cytotoxic filaments seen in amyotrophic lateral sclerosis (ALS) neurons.
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Affiliation(s)
- Yeongjin Baek
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, CALS, Seoul National University, Seoul, 08826, Republic of Korea
| | - Tae-Gyun Woo
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Jinsook Ahn
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, CALS, Seoul National University, Seoul, 08826, Republic of Korea.,Center for Food and Bioconvergence, Seoul National University, Seoul, 08826, Republic of Korea.,Center for Biomolecular and Cellular Structure, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea
| | - Dukwon Lee
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, CALS, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yonghoon Kwon
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, CALS, Seoul National University, Seoul, 08826, Republic of Korea
| | - Bum-Joon Park
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan, 46241, Republic of Korea
| | - Nam-Chul Ha
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, CALS, Seoul National University, Seoul, 08826, Republic of Korea. .,Center for Food and Bioconvergence, Seoul National University, Seoul, 08826, Republic of Korea.
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12
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Schneider KL, Ahmadpour D, Keuenhof KS, Eisele-Bürger AM, Berglund LL, Eisele F, Babazadeh R, Höög JL, Nyström T, Widlund PO. Using reporters of different misfolded proteins reveals differential strategies in processing protein aggregates. J Biol Chem 2022; 298:102476. [PMID: 36096201 PMCID: PMC9636550 DOI: 10.1016/j.jbc.2022.102476] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 11/18/2022] Open
Abstract
The accumulation of misfolded proteins is a hallmark of aging and many neurodegenerative diseases, making it important to understand how the cellular machinery recognizes and processes such proteins. A key question in this respect is whether misfolded proteins are handled in a similar way regardless of their genetic origin. To approach this question, we compared how three different misfolded proteins, guk1-7, gus1-3, and pro3-1, are handled by the cell. We show that all three are nontoxic, even though highly overexpressed, highlighting their usefulness in analyzing the cellular response to misfolding in the absence of severe stress. We found significant differences between the aggregation and disaggregation behavior of the misfolded proteins. Specifically, gus1-3 formed some aggregates that did not efficiently recruit the protein disaggregase Hsp104 and did not colocalize with the other misfolded reporter proteins. Strikingly, while all three misfolded proteins generally coaggregated and colocalized to specific sites in the cell, disaggregation was notably different; the rate of aggregate clearance of pro3-1 was faster than that of the other misfolded proteins, and its clearance rate was not hindered when pro3-1 colocalized with a slowly resolved misfolded protein. Finally, we observed using super-resolution light microscopy as well as immunogold labeling EM in which both showed an even distribution of the different misfolded proteins within an inclusion, suggesting that misfolding characteristics and remodeling, rather than spatial compartmentalization, allows for differential clearance of these misfolding reporters residing in the same inclusion. Taken together, our results highlight how properties of misfolded proteins can significantly affect processing.
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Affiliation(s)
- Kara L Schneider
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden
| | - Doryaneh Ahmadpour
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden; Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Katharina S Keuenhof
- Department for Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Anna Maria Eisele-Bürger
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden; Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Lisa Larsson Berglund
- Department for Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Frederik Eisele
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden
| | - Roja Babazadeh
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden
| | - Johanna L Höög
- Department for Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Thomas Nyström
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden
| | - Per O Widlund
- Institute for Biomedicine, Sahlgrenska Academy, Centre for Ageing and Health - AgeCap, University of Gothenburg, Gothenburg, Sweden.
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13
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Ruff KM, Choi YH, Cox D, Ormsby AR, Myung Y, Ascher DB, Radford SE, Pappu RV, Hatters DM. Sequence grammar underlying the unfolding and phase separation of globular proteins. Mol Cell 2022; 82:3193-3208.e8. [PMID: 35853451 PMCID: PMC10846692 DOI: 10.1016/j.molcel.2022.06.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 05/05/2022] [Accepted: 06/15/2022] [Indexed: 12/23/2022]
Abstract
Aberrant phase separation of globular proteins is associated with many diseases. Here, we use a model protein system to understand how the unfolded states of globular proteins drive phase separation and the formation of unfolded protein deposits (UPODs). We find that for UPODs to form, the concentrations of unfolded molecules must be above a threshold value. Additionally, unfolded molecules must possess appropriate sequence grammars to drive phase separation. While UPODs recruit molecular chaperones, their compositional profiles are also influenced by synergistic physicochemical interactions governed by the sequence grammars of unfolded proteins and cellular proteins. Overall, the driving forces for phase separation and the compositional profiles of UPODs are governed by the sequence grammars of unfolded proteins. Our studies highlight the need for uncovering the sequence grammars of unfolded proteins that drive UPOD formation and cause gain-of-function interactions whereby proteins are aberrantly recruited into UPODs.
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Affiliation(s)
- Kiersten M Ruff
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Yoon Hee Choi
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Dezerae Cox
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Angelique R Ormsby
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Yoochan Myung
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, VIC 3004, Australia; Structural Biology and Bioinformatics, Department of Biochemistry and Pharmacology, The University of Melbourne, Melbourne, VIC 3010, Australia; Systems and Computational Biology, Bio21 Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - David B Ascher
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, VIC 3004, Australia; Structural Biology and Bioinformatics, Department of Biochemistry and Pharmacology, The University of Melbourne, Melbourne, VIC 3010, Australia; Systems and Computational Biology, Bio21 Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Sheena E Radford
- Astbury Centre for Structural and Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Rohit V Pappu
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130, USA.
| | - Danny M Hatters
- Department of Biochemistry and Pharmacology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC 3010, Australia.
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14
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Tozawa T, Matsunaga K, Izumi T, Shigehisa N, Uekita T, Taoka M, Ichimura T. Ubiquitination-coupled liquid phase separation regulates the accumulation of the TRIM family of ubiquitin ligases into cytoplasmic bodies. PLoS One 2022; 17:e0272700. [PMID: 35930602 PMCID: PMC9355226 DOI: 10.1371/journal.pone.0272700] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 07/25/2022] [Indexed: 12/02/2022] Open
Abstract
Many members of the tripartite motif (TRIM) family of ubiquitin ligases localize in spherical, membrane-free structures collectively referred to as cytoplasmic bodies (CBs) in a concentration-dependent manner. These CBs may function as aggresome precursors or storage compartments that segregate potentially harmful excess TRIM molecules from the cytosolic milieu. However, the manner in which TRIM proteins accumulate into CBs is unclear. In the present study, using TRIM32, TRIM5α and TRIM63 as examples, we demonstrated that CBs are in a liquid droplet state, resulting from liquid-liquid phase separation (LLPS). This finding is based on criteria that defines phase-separated structures, such as recovery after photobleaching, sensitivity to hexanediol, and the ability to undergo fusion. CB droplets, which contain cyan fluorescent protein (CFP)-fused TRIM32, were purified from HEK293 cells using a fluorescence-activated cell sorter and analyzed by LC-MS/MS. We found that in addition to TRIM32, these droplets contain a variety of endogenous proteins and enzymes including ubiquitin. Localization of ubiquitin within CBs was further verified by fluorescence microscopy. We also found that the activation of the intracellular ubiquitination cascade promotes the assembly of TRIM32 molecules into CBs, whereas inhibition causes suppression. Regulation is dependent on the intrinsic E3 ligase activity of TRIM32. Similar regulation by ubiquitination on the TRIM assembly was also observed with TRIM5α and TRIM63. Our findings provide a novel mechanical basis for the organization of CBs that couples compartmentalization through LLPS with ubiquitination.
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Affiliation(s)
- Takafumi Tozawa
- Department of Applied Chemistry, National Defense Academy, Yokosuka, Kanagawa, Japan
| | - Kohichi Matsunaga
- Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan
| | - Tetsuro Izumi
- Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma, Japan
| | - Naotake Shigehisa
- Department of Applied Chemistry, National Defense Academy, Yokosuka, Kanagawa, Japan
| | - Takamasa Uekita
- Department of Applied Chemistry, National Defense Academy, Yokosuka, Kanagawa, Japan
| | - Masato Taoka
- Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
| | - Tohru Ichimura
- Department of Applied Chemistry, National Defense Academy, Yokosuka, Kanagawa, Japan
- * E-mail:
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15
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Crosstalk between Biomolecular Condensates and Proteostasis. Cells 2022; 11:cells11152415. [PMID: 35954258 PMCID: PMC9368065 DOI: 10.3390/cells11152415] [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: 05/30/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 12/23/2022] Open
Abstract
Proper homeostasis of the proteome, referred to as proteostasis, is maintained by chaperone-dependent refolding of misfolded proteins and by protein degradation via the ubiquitin-proteasome system and the autophagic machinery. This review will discuss a crosstalk between biomolecular condensates and proteostasis, whereby the crowding of proteostasis factors into macromolecular assemblies is often established by phase separation of membraneless biomolecular condensates. Specifically, ubiquitin and other posttranslational modifications come into play as agents of phase separation, essential for the formation of condensates and for ubiquitin-proteasome system activity. Furthermore, an intriguing connection associates malfunction of the same pathways to the accumulation of misfolded and ubiquitinated proteins in aberrant condensates, the formation of protein aggregates, and finally, to the pathogenesis of neurodegenerative diseases. The crosstalk between biomolecular condensates and proteostasis is an emerging theme in cellular and disease biology and further studies will focus on delineating specific molecular pathways involved in the pathogenesis of amyotrophic lateral sclerosis (ALS) and other neurodegenerative diseases.
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16
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Schwed-Gross A, Hamiel H, Faber GP, Angel M, Ben-Yishay R, Benichou JIC, Ishay-Ronen D, Shav-Tal Y. Glucocorticoids enhance chemotherapy-driven stress granule assembly and impair granule dynamics leading to cell death. J Cell Sci 2022; 135:276097. [PMID: 35713120 PMCID: PMC9450892 DOI: 10.1242/jcs.259629] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 06/13/2022] [Indexed: 11/20/2022] Open
Abstract
Stress granules (SGs) can assemble in cancer cells upon chemotoxic stress. Glucocorticoids function during stress responses and are administered with chemotherapies. The roles of glucocorticoids in SG assembly and disassembly pathways are unknown. We examined whether combining glucocorticoids such as cortisone with chemotherapies from the vinca alkaloid family, which dismantle the microtubule network, affects SG assembly and disassembly pathways and influences cell viability in cancer cells and human-derived organoids. Cortisone augmented SG formation when combined with vinorelbine (VRB). Live-cell imaging showed that cortisone increased SG assembly rates but reduced SG clearance rates after stress, by increasing protein residence times within the SGs. Mechanistically, VRB and cortisone signaled through the integrated stress response mediated by eIF2α (also known as EIF2S1), yet induced different kinases, with cortisone activating the GCN2 kinase (also known as EIF2AK4). Cortisone increased VRB-induced cell death and reduced the population of cells trapped in mitotic catastrophe. These effects were mediated by the core SG proteins G3BP1 and G3BP2. In conclusion, glucocorticoids induce SG assembly and cell death when administered with chemotherapies, suggesting that combining glucocorticoids with chemotherapies can enhance cancer cell chemosensitivity. Summary: Combining cortisone with the chemotherapy vinorelbine enhances the assembly of stress granules that are less likely to be cleared from the cells, augmenting vinorelbine-induced cell death.
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Affiliation(s)
- Avital Schwed-Gross
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Hila Hamiel
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Gabriel P Faber
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Mor Angel
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Rakefet Ben-Yishay
- Oncology Institute, Chaim Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Jennifer I C Benichou
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Dana Ishay-Ronen
- Oncology Institute, Chaim Sheba Medical Center, Tel-Hashomer, Ramat Gan, Israel
| | - Yaron Shav-Tal
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
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17
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Lambert-Smith IA, Saunders DN, Yerbury JJ. Progress in biophysics and molecular biology proteostasis impairment and ALS. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 174:3-27. [PMID: 35716729 DOI: 10.1016/j.pbiomolbio.2022.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 05/19/2022] [Accepted: 06/09/2022] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disease that results from the loss of both upper and lower motor neurons. It is the most common motor neuron disease and currently has no effective treatment. There is mounting evidence to suggest that disturbances in proteostasis play a significant role in ALS pathogenesis. Proteostasis is the maintenance of the proteome at the right level, conformation and location to allow a cell to perform its intended function. In this review, we present a thorough synthesis of the literature that provides evidence that genetic mutations associated with ALS cause imbalance to a proteome that is vulnerable to such pressure due to its metastable nature. We propose that the mechanism underlying motor neuron death caused by defects in mRNA metabolism and protein degradation pathways converges on proteostasis dysfunction. We propose that the proteostasis network may provide an effective target for therapeutic development in ALS.
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Affiliation(s)
- Isabella A Lambert-Smith
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Darren N Saunders
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
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18
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Upadhyay A, Sundaria N, Dhiman R, Prajapati VK, Prasad A, Mishra A. Complex Inclusion Bodies and Defective Proteome Hubs in Neurodegenerative Disease: New Clues, New Challenges. Neuroscientist 2022; 28:271-282. [PMID: 33530848 DOI: 10.1177/1073858421989582] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A healthy physiological environment of cells represents the dynamic homeostasis of crowded molecules. A subset of cellular proteome forms protein quality control (PQC) machinery to maintain an uninterrupted synthesis of new polypeptides and targeted elimination of old or defective proteins. The process of PQC may get overwhelmed under specific genetic mutations, environmental stress conditions, and aging-associated perturbances. Many of these conditions may lead to the generation of various types of aberrant protein species that may or may not accumulate as large cellular inclusions. These proteinaceous formations, referred to as inclusion bodies (IBs), could be membrane-bound or membrane-less, cytoplasmic, or nuclear. Most importantly, they could either be toxic or protective. Under acute stress conditions, the formation of aggregates may cause proteostasis failure, leading to large-scale changes in the cellular proteome compositions. However, the large insoluble IBs may act as reservoirs for many soluble proteins with high aggregation propensities, which can overwhelm the cellular chaperoning capacity and protein degradation machinery. The kinetic equilibrium between folding and unfolding, misfolding, and refolding; aggregation and degradation is perturbed in one or many neurodegenerative disorders (NDDs) associated with dementia, cognitive impairments, movement, and behavioural losses. However, a detailed interplay of IBs into the manifestation of the NDDs is unknown, and a very primitive knowledge of structural compositions of amyloid inclusions is present. The present article presents a brief evolutionary background of IBs; their functional relevance for prokaryotes, plants, and animals; and associated involvement in neuronal proteostasis.
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Affiliation(s)
- Arun Upadhyay
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Naveen Sundaria
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Rohan Dhiman
- Laboratory of Mycobacterial Immunology, Department of Life Science, National Institute of Technology, Rourkela, Odisha, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Ajmer, Rajasthan, India
| | - Amit Prasad
- School of Basic Sciences, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
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19
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Gupta G, Cappellini F, Farcal L, Gornati R, Bernardini G, Fadeel B. Copper oxide nanoparticles trigger macrophage cell death with misfolding of Cu/Zn superoxide dismutase 1 (SOD1). Part Fibre Toxicol 2022; 19:33. [PMID: 35538581 PMCID: PMC9088059 DOI: 10.1186/s12989-022-00467-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/29/2022] [Indexed: 01/05/2023] Open
Abstract
Background Copper oxide (CuO) nanoparticles (NPs) are known to trigger cytotoxicity in a variety of cell models, but the mechanism of cell death remains unknown. Here we addressed the mechanism of cytotoxicity in macrophages exposed to CuO NPs versus copper chloride (CuCl2). Methods The mouse macrophage cell line RAW264.7 was used as an in vitro model. Particle uptake and the cellular dose of Cu were investigated by transmission electron microscopy (TEM) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The deposition of Cu in lysosomes isolated from macrophages was also determined by ICP-MS. Cell viability (metabolic activity) was assessed using the Alamar Blue assay, and oxidative stress was monitored by a variety of methods including a luminescence-based assay for cellular glutathione (GSH), and flow cytometry-based detection of mitochondrial superoxide and mitochondrial membrane potential. Protein aggregation was determined by confocal microscopy using an aggresome-specific dye and protein misfolding was determined by circular dichroism (CD) spectroscopy. Lastly, proteasome activity was investigated using a fluorometric assay. Results We observed rapid cellular uptake of CuO NPs in macrophages with deposition in lysosomes. CuO NP-elicited cell death was characterized by mitochondrial swelling with signs of oxidative stress including the production of mitochondrial superoxide and cellular depletion of GSH. We also observed a dose-dependent accumulation of polyubiquitinated proteins and loss of proteasomal function in CuO NP-exposed cells, and we could demonstrate misfolding and mitochondrial translocation of superoxide dismutase 1 (SOD1), a Cu/Zn-dependent enzyme that plays a pivotal role in the defense against oxidative stress. The chelation of copper ions using tetrathiomolybdate (TTM) prevented cell death whereas inhibition of the cellular SOD1 chaperone aggravated toxicity. Moreover, CuO NP-triggered cell death was insensitive to the pan-caspase inhibitor, zVAD-fmk, and to wortmannin, an inhibitor of autophagy, implying that this was a non-apoptotic cell death. ZnO NPs, on the other hand, triggered autophagic cell death. Conclusions CuO NPs undergo dissolution in lysosomes leading to copper-dependent macrophage cell death characterized by protein misfolding and proteasomal insufficiency. Specifically, we present novel evidence for Cu-induced SOD1 misfolding which accords with the pronounced oxidative stress observed in CuO NP-exposed macrophages. These results are relevant for our understanding of the consequences of inadvertent human exposure to CuO NPs. Supplementary Information The online version contains supplementary material available at 10.1186/s12989-022-00467-w.
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Affiliation(s)
- Govind Gupta
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Nobels väg 13, Stockholm, Sweden
| | - Francesca Cappellini
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Nobels väg 13, Stockholm, Sweden.,Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Lucian Farcal
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Nobels väg 13, Stockholm, Sweden
| | - Rosalba Gornati
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Giovanni Bernardini
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Bengt Fadeel
- Division of Molecular Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Nobels väg 13, Stockholm, Sweden.
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20
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Spatial sequestration of misfolded proteins in neurodegenerative diseases. Biochem Soc Trans 2022; 50:759-771. [PMID: 35311889 DOI: 10.1042/bst20210862] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/28/2022] [Accepted: 03/02/2022] [Indexed: 12/12/2022]
Abstract
Properly folded, functional proteins are essential for cell health. Cells sustain protein homeostasis, or proteostasis, via protein quality control (PQC) mechanisms. It is currently hypothesized that a breakdown in proteostasis during ageing leads to the accumulation of protein aggregates in the cell and disease. Sequestration of misfolded proteins into PQC compartments represents one branch of the PQC network. In neurodegenerative diseases, certain proteins form abnormal protein deposits. Which PQC compartments house misfolded proteins associated with neurodegenerative diseases is still being investigated. It remains unclear if sequestration of these misfolded proteins is toxic or protective to the cell. Here, we review the current knowledge on various PQC compartments that form in the cell, the kinds of protein aggregates found in neurodegenerative diseases, and what is known about their sequestration. Understanding how protein sequestration occurs can shed light on why aggregates are toxic to the cell and are linked to neurodegenerative diseases like Huntington's, Alzheimer's, and Parkinson's diseases.
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21
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Sulatskaya AI, Kosolapova AO, Bobylev AG, Belousov MV, Antonets KS, Sulatsky MI, Kuznetsova IM, Turoverov KK, Stepanenko OV, Nizhnikov AA. β-Barrels and Amyloids: Structural Transitions, Biological Functions, and Pathogenesis. Int J Mol Sci 2021; 22:11316. [PMID: 34768745 PMCID: PMC8582884 DOI: 10.3390/ijms222111316] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 01/17/2023] Open
Abstract
Insoluble protein aggregates with fibrillar morphology called amyloids and β-barrel proteins both share a β-sheet-rich structure. Correctly folded β-barrel proteins can not only function in monomeric (dimeric) form, but also tend to interact with one another-followed, in several cases, by formation of higher order oligomers or even aggregates. In recent years, findings proving that β-barrel proteins can adopt cross-β amyloid folds have emerged. Different β-barrel proteins were shown to form amyloid fibrils in vitro. The formation of functional amyloids in vivo by β-barrel proteins for which the amyloid state is native was also discovered. In particular, several prokaryotic and eukaryotic proteins with β-barrel domains were demonstrated to form amyloids in vivo, where they participate in interspecies interactions and nutrient storage, respectively. According to recent observations, despite the variety of primary structures of amyloid-forming proteins, most of them can adopt a conformational state with the β-barrel topology. This state can be intermediate on the pathway of fibrillogenesis ("on-pathway state"), or can be formed as a result of an alternative assembly of partially unfolded monomers ("off-pathway state"). The β-barrel oligomers formed by amyloid proteins possess toxicity, and are likely to be involved in the development of amyloidoses, thus representing promising targets for potential therapy of these incurable diseases. Considering rapidly growing discoveries of the amyloid-forming β-barrels, we may suggest that their real number and diversity of functions are significantly higher than identified to date, and represent only "the tip of the iceberg". Here, we summarize the data on the amyloid-forming β-barrel proteins, their physicochemical properties, and their biological functions, and discuss probable means and consequences of the amyloidogenesis of these proteins, along with structural relationships between these two widespread types of β-folds.
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Affiliation(s)
- Anna I. Sulatskaya
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Anastasiia O. Kosolapova
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Alexander G. Bobylev
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 3 Institutskaya St., 142290 Moscow, Russia;
| | - Mikhail V. Belousov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Kirill S. Antonets
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Maksim I. Sulatsky
- Laboratory of Cell Morphology, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia;
| | - Irina M. Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Konstantin K. Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Olesya V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Anton A. Nizhnikov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
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22
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Méndez-López I, Sancho-Bielsa FJ, Engel T, García AG, Padín JF. Progressive Mitochondrial SOD1 G93A Accumulation Causes Severe Structural, Metabolic and Functional Aberrations through OPA1 Down-Regulation in a Mouse Model of Amyotrophic Lateral Sclerosis. Int J Mol Sci 2021; 22:ijms22158194. [PMID: 34360957 PMCID: PMC8347639 DOI: 10.3390/ijms22158194] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 07/22/2021] [Accepted: 07/28/2021] [Indexed: 01/20/2023] Open
Abstract
In recent years, the “non-autonomous motor neuron death” hypothesis has become more consolidated behind amyotrophic lateral sclerosis (ALS). It postulates that cells other than motor neurons participate in the pathology. In fact, the involvement of the autonomic nervous system is fundamental since patients die of sudden death when they become unable to compensate for cardiorespiratory arrest. Mitochondria are thought to play a fundamental role in the physiopathology of ALS, as they are compromised in multiple ALS models in different cell types, and it also occurs in other neurodegenerative diseases. Our study aimed to uncover mitochondrial alterations in the sympathoadrenal system of a mouse model of ALS, from a structural, bioenergetic and functional perspective during disease instauration. We studied the adrenal chromaffin cell from mutant SOD1G93A mouse at pre-symptomatic and symptomatic stages. The mitochondrial accumulation of the mutated SOD1G93A protein and the down-regulation of optic atrophy protein-1 (OPA1) provoke mitochondrial ultrastructure alterations prior to the onset of clinical symptoms. These changes affect mitochondrial fusion dynamics, triggering mitochondrial maturation impairment and cristae swelling, with increased size of cristae junctions. The functional consequences are a loss of mitochondrial membrane potential and changes in the bioenergetics profile, with reduced maximal respiration and spare respiratory capacity of mitochondria, as well as enhanced production of reactive oxygen species. This study identifies mitochondrial dynamics regulator OPA1 as an interesting therapeutic target in ALS. Additionally, our findings in the adrenal medulla gland from presymptomatic stages highlight the relevance of sympathetic impairment in this disease. Specifically, we show new SOD1G93A toxicity pathways affecting cellular energy metabolism in non-motor neurons, which offer a possible link between cell specific metabolic phenotype and the progression of ALS.
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Affiliation(s)
- Iago Méndez-López
- Instituto Teófilo Hernando and Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM), 28029 Madrid, Spain; (I.M.-L.); (A.G.G.)
| | - Francisco J. Sancho-Bielsa
- Departamento de Ciencias Médicas, Facultad de Medicina, Universidad de Castilla-La Mancha (UCLM), 13005 Ciudad Real, Spain;
| | - Tobias Engel
- Department of Physiology & Medical Physics, RCSI University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland;
- FutureNeuro SFI Research Centre for Chronic and Rare Neurological Diseases, RCSI University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
| | - Antonio G. García
- Instituto Teófilo Hernando and Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM), 28029 Madrid, Spain; (I.M.-L.); (A.G.G.)
| | - Juan Fernando Padín
- Instituto Teófilo Hernando and Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid (UAM), 28029 Madrid, Spain; (I.M.-L.); (A.G.G.)
- Departamento de Ciencias Médicas, Facultad de Medicina, Universidad de Castilla-La Mancha (UCLM), 13005 Ciudad Real, Spain;
- Correspondence:
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23
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Liu W, Xu Y, Li X, Meng Y, Wang H, Liu C, Liu C, Wang L. A DNA G-quadruplex converts SOD1 into fibrillar aggregates. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.01.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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24
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Molecular and pharmacological chaperones for SOD1. Biochem Soc Trans 2021; 48:1795-1806. [PMID: 32794552 PMCID: PMC7458393 DOI: 10.1042/bst20200318] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 12/25/2022]
Abstract
The efficacy of superoxide dismutase-1 (SOD1) folding impacts neuronal loss in motor system neurodegenerative diseases. Mutations can prevent SOD1 post-translational processing leading to misfolding and cytoplasmic aggregation in familial amyotrophic lateral sclerosis (ALS). Evidence of immature, wild-type SOD1 misfolding has also been observed in sporadic ALS, non-SOD1 familial ALS and Parkinson's disease. The copper chaperone for SOD1 (hCCS) is a dedicated and specific chaperone that assists SOD1 folding and maturation to produce the active enzyme. Misfolded or misfolding prone SOD1 also interacts with heat shock proteins and macrophage migration inhibitory factor to aid folding, refolding or degradation. Recognition of specific SOD1 structures by the molecular chaperone network and timely dissociation of SOD1-chaperone complexes are, therefore, important steps in SOD1 processing. Harnessing these interactions for therapeutic benefit is actively pursued as is the modulation of SOD1 behaviour with pharmacological and peptide chaperones. This review highlights the structural and mechanistic aspects of a selection of SOD1-chaperone interactions together with their impact on disease models.
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25
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Russo K, Wharton KA. BMP/TGF-β signaling as a modulator of neurodegeneration in ALS. Dev Dyn 2021; 251:10-25. [PMID: 33745185 DOI: 10.1002/dvdy.333] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/19/2022] Open
Abstract
This commentary focuses on the emerging intersection between BMP/TGF-β signaling roles in nervous system function and the amyotrophic lateral sclerosis (ALS) disease state. Future research is critical to elucidate the molecular underpinnings of this intersection of the cellular processes disrupted in ALS and those influenced by BMP/TGF-β signaling, including synapse structure, neurotransmission, plasticity, and neuroinflammation. Such knowledge promises to inform us of ideal entry points for the targeted modulation of dysfunctional cellular processes in an effort to abrogate ALS pathologies. It is likely that different interventions are required, either at discrete points in disease progression, or across multiple dysfunctional processes which together lead to motor neuron degeneration and death. We discuss the challenging, but intriguing idea that modulation of the pleiotropic nature of BMP/TGF-β signaling could be advantageous, as a way to simultaneously treat defects in more than one cell process across different forms of ALS.
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Affiliation(s)
- Kathryn Russo
- Department of Neuroscience, Brown University, Providence, Rhode Island, USA.,Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, USA
| | - Kristi A Wharton
- Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, USA.,Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, USA
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26
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Amen T, Kaganovich D. Quantitative photoconversion analysis of internal molecular dynamics in stress granules and other membraneless organelles in live cells. STAR Protoc 2020; 1:100217. [PMID: 33377110 PMCID: PMC7757677 DOI: 10.1016/j.xpro.2020.100217] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Photoconversion enables real-time labeling of protein sub-populations inside living cells, which can then be tracked with submicrometer resolution. Here, we detail the protocol of comparing protein dynamics inside membraneless organelles in live HEK293T cells using a CRISPR-Cas9 PABPC1-Dendra2 marker of stress granules. Measuring internal dynamics of membraneless organelles provides insight into their functional state, physical properties, and composition. Photoconversion has the advantage over other imaging techniques in that it is less phototoxic and allows for dual color tracking of proteins. For complete details on the use and execution of this protocol, please refer to Amen and Kaganovich (2020). Photoconversion microscopy enables the measurement of protein dynamics in stress granules Protocol describes the construction of CRISPR-Cas9 stress granule photoconversion marker Protocol can measure the internal dynamics of other membraneless organelles in live cells
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Affiliation(s)
- Triana Amen
- Department of Experimental Neurodegeneration, University Medical Center Goettingen, Goettingen 37073, Germany
| | - Daniel Kaganovich
- Department of Experimental Neurodegeneration, University Medical Center Goettingen, Goettingen 37073, Germany.,Base Pharmaceuticals, Boston, MA 02129, USA
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27
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Johnston HE, Samant RS. Alternative systems for misfolded protein clearance: life beyond the proteasome. FEBS J 2020; 288:4464-4487. [PMID: 33135311 DOI: 10.1111/febs.15617] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/15/2020] [Accepted: 10/30/2020] [Indexed: 12/18/2022]
Abstract
Protein misfolding is a major driver of ageing-associated frailty and disease pathology. Although all cells possess multiple, well-characterised protein quality control systems to mitigate the toxicity of misfolded proteins, how they are integrated to maintain protein homeostasis ('proteostasis') in health-and how their disintegration contributes to disease-is still an exciting and fast-paced area of research. Under physiological conditions, the predominant route for misfolded protein clearance involves ubiquitylation and proteasome-mediated degradation. When the capacity of this route is overwhelmed-as happens during conditions of acute environmental stress, or chronic ageing-related decline-alternative routes for protein quality control are activated. In this review, we summarise our current understanding of how proteasome-targeted misfolded proteins are retrafficked to alternative protein quality control routes such as juxta-nuclear sequestration and selective autophagy when the ubiquitin-proteasome system is compromised. We also discuss the molecular determinants of these alternative protein quality control systems, attempt to clarify distinctions between various cytoplasmic spatial quality control inclusion bodies (e.g., Q-bodies, p62 bodies, JUNQ, aggresomes, and aggresome-like induced structures 'ALIS'), and speculate on emerging concepts in the field that we hope will spur future research-with the potential to benefit the rational development of healthy ageing strategies.
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Affiliation(s)
| | - Rahul S Samant
- Signalling Programme, The Babraham Institute, Cambridge, UK
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28
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Abstract
Vimentin is one of the first cytoplasmic intermediate filaments to be expressed in mammalian cells during embryogenesis, but its role in cellular fitness has long been a mystery. Vimentin is acknowledged to play a role in cell stiffness, cell motility, and cytoplasmic organization, yet it is widely considered to be dispensable for cellular function and organismal development. Here, we show that Vimentin plays a role in cellular stress response in differentiating cells, by recruiting aggregates, stress granules, and RNA-binding proteins, directing their elimination and asymmetric partitioning. In the absence of Vimentin, pluripotent embryonic stem cells fail to differentiate properly, with a pronounced deficiency in neuronal differentiation. Our results uncover a novel function for Vimentin, with important implications for development, tissue homeostasis, and in particular, stress response.
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29
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McAlary L, Chew YL, Lum JS, Geraghty NJ, Yerbury JJ, Cashman NR. Amyotrophic Lateral Sclerosis: Proteins, Proteostasis, Prions, and Promises. Front Cell Neurosci 2020; 14:581907. [PMID: 33328890 PMCID: PMC7671971 DOI: 10.3389/fncel.2020.581907] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of the motor neurons that innervate muscle, resulting in gradual paralysis and culminating in the inability to breathe or swallow. This neuronal degeneration occurs in a spatiotemporal manner from a point of onset in the central nervous system (CNS), suggesting that there is a molecule that spreads from cell-to-cell. There is strong evidence that the onset and progression of ALS pathology is a consequence of protein misfolding and aggregation. In line with this, a hallmark pathology of ALS is protein deposition and inclusion formation within motor neurons and surrounding glia of the proteins TAR DNA-binding protein 43, superoxide dismutase-1, or fused in sarcoma. Collectively, the observed protein aggregation, in conjunction with the spatiotemporal spread of symptoms, strongly suggests a prion-like propagation of protein aggregation occurs in ALS. In this review, we discuss the role of protein aggregation in ALS concerning protein homeostasis (proteostasis) mechanisms and prion-like propagation. Furthermore, we examine the experimental models used to investigate these processes, including in vitro assays, cultured cells, invertebrate models, and murine models. Finally, we evaluate the therapeutics that may best prevent the onset or spread of pathology in ALS and discuss what lies on the horizon for treating this currently incurable disease.
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Affiliation(s)
- Luke McAlary
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Yee Lian Chew
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Jeremy Stephen Lum
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Nicholas John Geraghty
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Justin John Yerbury
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Neil R. Cashman
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
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30
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Tompa DR, Muthusamy S, Srikanth S, Kadhirvel S. Molecular dynamics of far positioned surface mutations of Cu/Zn SOD1 promotes altered structural stability and metal-binding site: Structural clues to the pathogenesis of amyotrophic lateral sclerosis. J Mol Graph Model 2020; 100:107678. [PMID: 32768728 DOI: 10.1016/j.jmgm.2020.107678] [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: 03/14/2020] [Revised: 06/18/2020] [Accepted: 06/26/2020] [Indexed: 10/23/2022]
Abstract
Cu/Zn superoxide dismutase (SOD1) mutations are associated to the motor neuron disorder, amyotrophic lateral sclerosis (ALS), which is characterized by aggregates of the misfolded proteins. The distribution of mutations all over the three-dimensional structure of SOD1 makes it complex to determine the exact molecular mechanism underlying SOD1 destabilization and the associated ALS pathology. In this study, we have examined structure and dynamics of SOD1 protein upon two ALS associated point mutations at the surface residue Glu100 (E100G and E100K), which is located far from the Cu and Zn sites and dimer interface. The molecular dynamics simulations were performed for these mutants for 50ns using GROMACS package. Our results indicate that the mutations result in structural destabilization by affecting the gate keeping role of Glu100 and loss of electrostatic interactions on the protein surface which stabilizes the β-barrel structure of the native form. Further, these mutations could increase the fluctuations in the zinc-binding loop (loop IV), primarily due to loss of hydrogen bond between Asp101 and Arg79. The relaxed conformation of Arg79 further affects the native conformation of His80 and Asp83, that results in altered zinc site geometry and the structure of the substrate channel. Our results clearly suggest that, similar to the mutations located at metal sites/dimer interface/disulfide regions, the mutations at the far positioned site (Glu100) also induce significant conformational changes that could affect the metallation and structure of SOD1 molecule, resulting in formation of toxic intermediate species that cause ALS.
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Affiliation(s)
- Dharma Rao Tompa
- Biomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, 613401, Tamil Nadu, India
| | - Sureshan Muthusamy
- Biomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, 613401, Tamil Nadu, India
| | - Srimari Srikanth
- Biomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, 613401, Tamil Nadu, India
| | - Saraboji Kadhirvel
- Biomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, 613401, Tamil Nadu, India.
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31
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Jung KH, Zhang X. Fluorogenic detection of protein aggregates in live cells using the AggTag method. Methods Enzymol 2020; 639:1-22. [PMID: 32475397 DOI: 10.1016/bs.mie.2020.04.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Protein aggregation is a process that occurs through the self-assembly of misfolded proteins to form soluble oligomers and insoluble aggregates. While there has been significant interest in protein aggregation for neurodegenerative diseases, progress in this field of research has been limited by the lack of effective methods to detect and interrogate these species in live cells. To resolve this issue, we have developed a new imaging method named the AggTag to report on protein aggregation in live cells with fluorescence microscopy. The AggTag method utilizes a genetic fusion of a protein of interest (POI) to a protein tag to conjugate with the AggTag probe, which contains a fluorophore that turns on its fluorescence upon interaction with protein aggregates. Unlike the conventional methods, this method enables one to detect soluble misfolded oligomers that were previously invisible. Furthermore, the AggTag method has been applied for the simultaneous detection of co-aggregation between two different POIs by a dual-color and orthogonal tagging system. This chapter aims to provide step-by-step procedures of the AggTag method for researchers who intend to study aggregation of POIs in mammalian cell lines.
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Affiliation(s)
- Kwan Ho Jung
- Department of Chemistry, The Pennsylvania State University, University Park, PA, United States
| | - Xin Zhang
- Department of Chemistry, The Pennsylvania State University, University Park, PA, United States; Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States; The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States.
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32
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Chaudhuri P, Prajapati KP, Anand BG, Dubey K, Kar K. Amyloid cross-seeding raises new dimensions to understanding of amyloidogenesis mechanism. Ageing Res Rev 2019; 56:100937. [PMID: 31430565 DOI: 10.1016/j.arr.2019.100937] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/21/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022]
Abstract
Hallmarks of most of the amyloid pathologies are surprisingly found to be heterocomponent entities such as inclusions and plaques which contain diverse essential proteins and metabolites. Experimental studies have already revealed the occurrence of coaggregation and cross-seeding during amyloid formation of several proteins and peptides, yielding multicomponent assemblies of amyloid nature. Further, research reports on the co-occurrence of more than one type of amyloid-linked pathologies in the same individual suggest the possible cross-talk among the disease related amyloidogenic protein species during their amyloid growth. In this review paper, we have tried to gain more insight into the process of coaggregation and cross-seeding during amyloid aggregation of proteins, particularly focusing on their relevance to the pathogenesis of the protein misfolding diseases. Revelation of amyloid cross-seeding and coaggregation seems to open new dimensions in our mechanistic understanding of amyloidogenesis and such knowledge may possibly inspire better designing of anti-amyloid therapeutics.
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33
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Abstract
Few proteins have come under such intense scrutiny as superoxide dismutase-1 (SOD1). For almost a century, scientists have dissected its form, function and then later its malfunction in the neurodegenerative disease amyotrophic lateral sclerosis (ALS). We now know SOD1 is a zinc and copper metalloenzyme that clears superoxide as part of our antioxidant defence and respiratory regulation systems. The possibility of reduced structural integrity was suggested by the first crystal structures of human SOD1 even before deleterious mutations in the sod1 gene were linked to the ALS. This concept evolved in the intervening years as an impressive array of biophysical studies examined the characteristics of mutant SOD1 in great detail. We now recognise how ALS-related mutations perturb the SOD1 maturation processes, reduce its ability to fold and reduce its thermal stability and half-life. Mutant SOD1 is therefore predisposed to monomerisation, non-canonical self-interactions, the formation of small misfolded oligomers and ultimately accumulation in the tell-tale insoluble inclusions found within the neurons of ALS patients. We have also seen that several post-translational modifications could push wild-type SOD1 down this toxic pathway. Recently we have come to view ALS as a prion-like disease where both the symptoms, and indeed SOD1 misfolding itself, are transmitted to neighbouring cells. This raises the possibility of intervention after the initial disease presentation. Several small-molecule and biologic-based strategies have been devised which directly target the SOD1 molecule to change the behaviour thought to be responsible for ALS. Here we provide a comprehensive review of the many biophysical advances that sculpted our view of SOD1 biology and the recent work that aims to apply this knowledge for therapeutic outcomes in ALS.
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34
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Bolognesi B, Faure AJ, Seuma M, Schmiedel JM, Tartaglia GG, Lehner B. The mutational landscape of a prion-like domain. Nat Commun 2019; 10:4162. [PMID: 31519910 PMCID: PMC6744496 DOI: 10.1038/s41467-019-12101-z] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/15/2019] [Indexed: 12/11/2022] Open
Abstract
Insoluble protein aggregates are the hallmarks of many neurodegenerative diseases. For example, aggregates of TDP-43 occur in nearly all cases of amyotrophic lateral sclerosis (ALS). However, whether aggregates cause cellular toxicity is still not clear, even in simpler cellular systems. We reasoned that deep mutagenesis might be a powerful approach to disentangle the relationship between aggregation and toxicity. We generated >50,000 mutations in the prion-like domain (PRD) of TDP-43 and quantified their toxicity in yeast cells. Surprisingly, mutations that increase hydrophobicity and aggregation strongly decrease toxicity. In contrast, toxic variants promote the formation of dynamic liquid-like condensates. Mutations have their strongest effects in a hotspot that genetic interactions reveal to be structured in vivo, illustrating how mutagenesis can probe the in vivo structures of unstructured proteins. Our results show that aggregation of TDP-43 is not harmful but protects cells, most likely by titrating the protein away from a toxic liquid-like phase. TDP43 aggregates are a hallmark of amyotrophic lateral sclerosis. By using deep mutagenesis to measure the toxicity of more than 50,000 mutations in the prion domain of TDP43, the authors conclude that mutations that increase toxicity promote formation of liquid-like condensates, while aggregation of TDP43 is protective for the cell.
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Affiliation(s)
- Benedetta Bolognesi
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain. .,Institute of Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain.
| | - Andre J Faure
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain
| | - Mireia Seuma
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain.,Institute of Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jörn M Schmiedel
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain
| | - Gian Gaetano Tartaglia
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain.,Department of Biology 'Charles Darwin', Sapienza University of Rome, P.le A. Moro 5, Rome, 00185, Italy
| | - Ben Lehner
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain.
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35
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Jung KH, Kim SF, Liu Y, Zhang X. A Fluorogenic
AggTag
Method Based on Halo‐ and SNAP‐Tags to Simultaneously Detect Aggregation of Two Proteins in Live Cells. Chembiochem 2019; 20:1078-1087. [DOI: 10.1002/cbic.201800782] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Kwan Ho Jung
- Department of ChemistryThe Pennsylvania State University University Park PA 16802 USA
| | - Sojung F. Kim
- Department of ChemistryThe Pennsylvania State University University Park PA 16802 USA
| | - Yu Liu
- Department of ChemistryThe Pennsylvania State University University Park PA 16802 USA
| | - Xin Zhang
- Department of ChemistryThe Pennsylvania State University University Park PA 16802 USA
- Department of Biochemistry and Molecular BiologyThe Pennsylvania State University University Park PA 16802 USA
- The Huck Institutes of the Life SciencesThe Pennsylvania State University University Park PA 16802 USA
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36
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Sala FA, Wright GSA, Antonyuk SV, Garratt RC, Hasnain SS. Molecular recognition and maturation of SOD1 by its evolutionarily destabilised cognate chaperone hCCS. PLoS Biol 2019; 17:e3000141. [PMID: 30735496 PMCID: PMC6383938 DOI: 10.1371/journal.pbio.3000141] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 02/21/2019] [Accepted: 01/22/2019] [Indexed: 11/19/2022] Open
Abstract
Superoxide dismutase-1 (SOD1) maturation comprises a string of posttranslational modifications which transform the nascent peptide into a stable and active enzyme. The successive folding, metal ion binding, and disulphide acquisition steps in this pathway can be catalysed through a direct interaction with the copper chaperone for SOD1 (CCS). This process confers enzymatic activity and reduces access to noncanonical, aggregation-prone states. Here, we present the functional mechanisms of human copper chaperone for SOD1 (hCCS)-catalysed SOD1 activation based on crystal structures of reaction precursors, intermediates, and products. Molecular recognition of immature SOD1 by hCCS is driven by several interface interactions, which provide an extended surface upon which SOD1 folds. Induced-fit complexation is reliant on the structural plasticity of the immature SOD1 disulphide sub-loop, a characteristic which contributes to misfolding and aggregation in neurodegenerative disease. Complexation specifically stabilises the SOD1 disulphide sub-loop, priming it and the active site for copper transfer, while delaying disulphide formation and complex dissociation. Critically, a single destabilising amino acid substitution within the hCCS interface reduces hCCS homodimer affinity, creating a pool of hCCS available to interact with immature SOD1. hCCS substrate specificity, segregation between solvent and biological membranes, and interaction transience are direct results of this substitution. In this way, hCCS-catalysed SOD1 maturation is finessed to minimise copper wastage and reduce production of potentially toxic SOD1 species.
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Affiliation(s)
- Fernanda A. Sala
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, Brazil
- Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, Brazil
| | - Gareth S. A. Wright
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Richard C. Garratt
- Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, Brazil
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
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37
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Solcia E, Necchi V, Sommi P, Ricci V. Proteasome-Rich PaCS as an Oncofetal UPS Structure Handling Cytosolic Polyubiquitinated Proteins. In Vivo Occurrence, in Vitro Induction, and Biological Role. Int J Mol Sci 2018; 19:ijms19092767. [PMID: 30223470 PMCID: PMC6164709 DOI: 10.3390/ijms19092767] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 09/11/2018] [Indexed: 11/16/2022] Open
Abstract
In this article, we outline and discuss available information on the cellular site and mechanism of proteasome interaction with cytosolic polyubiquitinated proteins and heat-shock molecules. The particulate cytoplasmic structure (PaCS) formed by barrel-like particles, closely reproducing in vivo the high-resolution structure of 26S proteasome as isolated in vitro, has been detected in a variety of fetal and neoplastic cells, from living tissue or cultured cell lines. Specific trophic factors and interleukins were found to induce PaCS during in vitro differentiation of dendritic, natural killer (NK), or megakaryoblastic cells, apparently through activation of the MAPK-ERK pathway. Direct interaction of CagA bacterial oncoprotein with proteasome was shown inside the PaCSs of a Helicobacter pylori-infected gastric epithelium, a finding suggesting a role for PaCS in CagA-mediated gastric carcinogenesis. PaCS dissolution and autophagy were seen after withdrawal of inducing factors. PaCS-filled cell blebs and ectosomes were found in some cells and may represent a potential intercellular discharge and transport system of polyubiquitinated antigenic proteins. PaCS differs substantially from the inclusion bodies, sequestosomes, and aggresomes reported in proteinopathies like Huntington or Parkinson diseases, which usually lack PaCS. The latter seems more linked to conditions of increased cell proliferation/differentiation, implying an increased functional demand to the ubiquitin–proteasome system.
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Affiliation(s)
- Enrico Solcia
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
- Pathologic Anatomy Unit, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy.
| | - Vittorio Necchi
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
- Centro Grandi Strumenti, University of Pavia, 27100 Pavia, Italy.
| | - Patrizia Sommi
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
| | - Vittorio Ricci
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
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38
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Rothe S, Prakash A, Tyedmers J. The Insoluble Protein Deposit (IPOD) in Yeast. Front Mol Neurosci 2018; 11:237. [PMID: 30050408 PMCID: PMC6052365 DOI: 10.3389/fnmol.2018.00237] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 06/18/2018] [Indexed: 11/13/2022] Open
Abstract
The appearance of protein aggregates is a hallmark of several pathologies including many neurodegenerative diseases. Mounting evidence suggests that the accumulation of misfolded proteins into inclusions is a secondary line of defense when the extent of protein misfolding exceeds the capacity of the Protein Quality Control System, which mediates refolding or degradation of misfolded species. Such exhaustion can occur during severe proteotoxic stress, the excessive occurrence of aggregation prone protein species, e.g., amyloids, or during ageing. However, the machinery that mediates recognition, recruitment and deposition of different types of misfolded proteins into specific deposition sites is only poorly understood. Since emerging principles of aggregate deposition appear evolutionarily conserved, yeast represents a powerful model to study basic mechanisms of recognition of different types of misfolded proteins, their recruitment to the respective deposition site and the molecular organization at the corresponding site. Yeast possesses at least three different aggregate deposition sites, one of which is a major deposition site for amyloid aggregates termed Insoluble PrOtein Deposit (IPOD). Due to the link between neurodegenerative disease and accumulation of amyloid aggregates, the IPOD is of particular interest when we aim to identify the molecular mechanisms that cells have evolved to counteract toxicity associated with the occurrence of amyloid aggregates. Here, we will review what is known about IPOD composition and the mechanisms of recognition and recruitment of amyloid aggregates to this site in yeast. Finally, we will briefly discuss the possible physiological role of aggregate deposition at the IPOD.
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Affiliation(s)
- Stephanie Rothe
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
| | - Abaya Prakash
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
| | - Jens Tyedmers
- Department of Medicine I and Clinical Chemistry, Heidelberg University Hospital, Heidelberg, Germany
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39
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FUS(1-359) transgenic mice as a model of ALS: pathophysiological and molecular aspects of the proteinopathy. Neurogenetics 2018; 19:189-204. [DOI: 10.1007/s10048-018-0553-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022]
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40
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Farrawell NE, Lambert-Smith I, Mitchell K, McKenna J, McAlary L, Ciryam P, Vine KL, Saunders DN, Yerbury JJ. SOD1 A4V aggregation alters ubiquitin homeostasis in a cell model of ALS. J Cell Sci 2018; 131:jcs.209122. [PMID: 29748379 DOI: 10.1242/jcs.209122] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 05/01/2018] [Indexed: 12/11/2022] Open
Abstract
A hallmark of amyotrophic lateral sclerosis (ALS) pathology is the accumulation of ubiquitylated protein inclusions within motor neurons. Recent studies suggest the sequestration of ubiquitin (Ub) into inclusions reduces the availability of free Ub, which is essential for cellular function and survival. However, the dynamics of the Ub landscape in ALS have not yet been described. Here, we show that Ub homeostasis is altered in a cell model of ALS induced by expressing mutant SOD1 (SOD1A4V). By monitoring the distribution of Ub in cells expressing SOD1A4V, we show that Ub is present at the earliest stages of SOD1A4V aggregation, and that cells containing SOD1A4V aggregates have greater ubiquitin-proteasome system (UPS) dysfunction. Furthermore, SOD1A4V aggregation is associated with the redistribution of Ub and depletion of the free Ub pool. Ubiquitomics analysis indicates that expression of SOD1A4V is associated with a shift of Ub to a pool of supersaturated proteins, including those associated with oxidative phosphorylation and metabolism, corresponding with altered mitochondrial morphology and function. Taken together, these results suggest that misfolded SOD1 contributes to UPS dysfunction and that Ub homeostasis is an important target for monitoring pathological changes in ALS.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Natalie E Farrawell
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522.,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522
| | - Isabella Lambert-Smith
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522.,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522
| | - Kristen Mitchell
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522.,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522
| | - Jessie McKenna
- School of Medical Sciences, Faculty of Medicine, UNSW Australia 2052
| | - Luke McAlary
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522.,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522.,Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 2B5
| | - Prajwal Ciryam
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.,Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208-3500, USA.,Department of Neurology, Columbia University College of Physicians & Surgeons, New York, NY 10032-3784, USA
| | - Kara L Vine
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522.,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522
| | - Darren N Saunders
- School of Medical Sciences, Faculty of Medicine, UNSW Australia 2052
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia 2522 .,Molecular Horizons and School of Chemistry & Molecular Bioscience, University of Wollongong, NSW, Australia 2522
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41
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Medinas DB, Valenzuela V, Hetz C. Proteostasis disturbance in amyotrophic lateral sclerosis. Hum Mol Genet 2018; 26:R91-R104. [PMID: 28977445 DOI: 10.1093/hmg/ddx274] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 07/11/2017] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting motoneurons in the brain and spinal cord leading to paralysis and death. Although the etiology of ALS remains poorly understood, abnormal protein aggregation and altered proteostasis are common features of sporadic and familial ALS forms. The proteostasis network is decomposed into different modules highly conserved across species and comprehends a collection of mechanisms related to protein synthesis, folding, trafficking, secretion and degradation that is distributed in different compartments inside the cell. Functional studies in various ALS models are revealing a complex scenario where distinct and even opposite effects in disease progression are observed depending on the targeted component of the proteostasis network. Importantly, alteration of the folding capacity of the endoplasmic reticulum (ER) is becoming a common pathological alteration in ALS, representing one of the earliest defects observed in disease models, contributing to denervation and motoneuron dysfunction. Strategies to target-specific components of the proteostasis network using small molecules and gene therapy are under development, and promise interesting avenues for future interventions to delay or stop ALS progression.
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Affiliation(s)
- Danilo B Medinas
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Vicente Valenzuela
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Geroscience, Brain Health and Metabolism, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile.,Center for Geroscience, Brain Health and Metabolism, Santiago, Chile.,Buck Institute for Research on Aging, Novato, CA, USA.,Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
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42
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Specification of Physiologic and Disease States by Distinct Proteins and Protein Conformations. Cell 2017; 171:1001-1014. [PMID: 29149602 DOI: 10.1016/j.cell.2017.10.047] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 10/27/2017] [Accepted: 10/30/2017] [Indexed: 12/15/2022]
Abstract
Protein conformational states-from intrinsically disordered ensembles to amyloids that underlie the self-templating, infectious properties of prion-like proteins-have attracted much attention. Here, we highlight the diversity, including differences in biophysical properties, that drive distinct biological functions and pathologies among self-templating proteins. Advances in chemical genomics, gene editing, and model systems now permit deconstruction of the complex interplay between these protein states and the host factors that react to them. These methods reveal that conformational switches modulate normal and abnormal information transfer and that intimate relationships exist between the intrinsic function of proteins and the deleterious consequences of their misfolding.
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43
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There Is an Inclusion for That: Material Properties of Protein Granules Provide a Platform for Building Diverse Cellular Functions. Trends Biochem Sci 2017; 42:765-776. [DOI: 10.1016/j.tibs.2017.08.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 07/26/2017] [Accepted: 08/03/2017] [Indexed: 12/30/2022]
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44
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Brasil AA, Magalhães RSS, De Carvalho MDC, Paiva I, Gerhardt E, Pereira MD, Outeiro TF, Eleutherio ECA. Implications of fALS Mutations on Sod1 Function and Oligomerization in Cell Models. Mol Neurobiol 2017; 55:5269-5281. [PMID: 28884318 PMCID: PMC5948255 DOI: 10.1007/s12035-017-0755-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/23/2017] [Indexed: 02/07/2023]
Abstract
Among the familial forms of amyotrophic lateral sclerosis (fALS), 20% are associated with the Cu,Zn-superoxide dismutase (Sod1). fALS is characterized by the accumulation of aggregated proteins and the increase in oxidative stress markers. Here, we used the non-invasive bimolecular fluorescence complementation (BiFC) assay in human H4 cells to investigate the kinetics of aggregation and subcellular localization of Sod1 mutants. We also studied the effect of the different Sod1 mutants to respond against oxidative stress by following the levels of reactive oxygen species (ROS) after treatment with hydrogen peroxide. Our results showed that only 30% of cells transfected with A4VSod1 showed no inclusions while for the other Sod1 mutants tested (L38V, G93A and G93C), this percentage was at least 70%. In addition, we found that 10% of cells transfected with A4VSod1 displayed more than five inclusions per cell and that A4V and G93A Sod1 formed inclusions more rapidly than L38V and G93C Sod1. Expression of WTSod1 significantly decreased the intracellular oxidation levels in comparison with expression of fALS Sod1 mutants, suggesting the mutations induce a functional impairment. All fALS mutations impaired nuclear localization of Sod1, which is important for maintaining genomic stability. Consistently, expression of WTSod1, but not of fALS Sod1 mutants, reduced DNA damage, as measured by the comet assay. Altogether, our study sheds light into the effects of fALS Sod1 mutations on inclusion formation, dynamics, and localization as well as on antioxidant response, opening novel avenues for investigating the role of fALS Sod1 mutations in pathogenesis.
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Affiliation(s)
- Aline A Brasil
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany.,Departamento de Química, Instituto de Química, Centro de Tecnologia, Cidade Universitária, Universidade Federal do Rio de Janeir, Av. Athos da Silveira Ramos, n 149, Bloco A - sala 547, Rio de Janeiro, RJ, 21941-909, Brazil
| | - Rayne S S Magalhães
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany.,Departamento de Química, Instituto de Química, Centro de Tecnologia, Cidade Universitária, Universidade Federal do Rio de Janeir, Av. Athos da Silveira Ramos, n 149, Bloco A - sala 547, Rio de Janeiro, RJ, 21941-909, Brazil
| | - Mariana D C De Carvalho
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany.,Departamento de Química, Instituto de Química, Centro de Tecnologia, Cidade Universitária, Universidade Federal do Rio de Janeir, Av. Athos da Silveira Ramos, n 149, Bloco A - sala 547, Rio de Janeiro, RJ, 21941-909, Brazil
| | - Isabel Paiva
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany
| | - Ellen Gerhardt
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany
| | - Marcos D Pereira
- Departamento de Química, Instituto de Química, Centro de Tecnologia, Cidade Universitária, Universidade Federal do Rio de Janeir, Av. Athos da Silveira Ramos, n 149, Bloco A - sala 547, Rio de Janeiro, RJ, 21941-909, Brazil
| | - Tiago F Outeiro
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany. .,Max Planck Institute for Experimental Medicine, Göttingen, Germany.
| | - Elis C A Eleutherio
- Departamento de Química, Instituto de Química, Centro de Tecnologia, Cidade Universitária, Universidade Federal do Rio de Janeir, Av. Athos da Silveira Ramos, n 149, Bloco A - sala 547, Rio de Janeiro, RJ, 21941-909, Brazil.
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45
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Jang JY, Cho H, Park HY, Rhim H, Kang S. ALS-linked mutant SOD1 proteins promote Aβ aggregates in ALS through direct interaction with Aβ. Biochem Biophys Res Commun 2017; 493:697-707. [PMID: 28864422 DOI: 10.1016/j.bbrc.2017.08.127] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 08/28/2017] [Indexed: 12/16/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons. Aggregation of ALS-linked mutant Cu/Zn superoxide dismutase (SOD1) is a hallmark of a subset of familial ALS (fALS). Recently, intracellular amyloid-β (Aβ) is detected in motor neurons of both sporadic and familial ALS. We have previously shown that intracellular Aβ specifically interacts with G93A, an ALS-linked SOD1 mutant. However, little is known about the pathological and biological effect of this interaction in neurons. In this study, we have demonstrated that the Aβ-binding region is exposed on the SOD1 surface through the conformational changes due to misfolding of SOD1. Interestingly, we found that the intracellular aggregation of Aβ is enhanced through the direct interaction of Aβ with the Aβ-binding region exposed to misfolded SOD1. Ultimately, increased Aβ aggregation by this interaction promotes neuronal cell death. Consistent with this result, Aβ aggregates was three-fold higher in the brains of G93A transgenic mice than those of non Tg. Our study provides the first direct evidence that Aβ, an AD-linked factor, is associated to the pathogenesis of ALS and provides molecular clues to understand common aggregation mechanisms in the pathogenesis of neurodegenerative diseases. Furthermore, it will provide new insights into the development of therapeutic approaches for ALS.
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Affiliation(s)
- Ja-Young Jang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Hyungmin Cho
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Hye-Yoon Park
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Hyangshuk Rhim
- Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
| | - Seongman Kang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea.
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46
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Govindarajalu G, Selvam M, Palchamy E, Baluchamy S. N-terminal truncations of human bHLH transcription factor Twist1 leads to the formation of aggresomes. Mol Cell Biochem 2017; 439:75-85. [PMID: 28779345 DOI: 10.1007/s11010-017-3137-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 08/01/2017] [Indexed: 01/25/2023]
Abstract
In the cell, misfolded proteins are processed by molecular chaperone-mediated refolding or through ubiquitin-mediated proteosome system. Dysregulation of these mechanisms facilitates the aggregation of misfolded proteins and forms aggresomes in the juxta nuclear position of the cell which are removed by lysosome-mediated autophagy pathway in the subsequent cell division. Accumulation of misfolded proteins in the cell is hallmark of several neurological disorders and other diseases including cancer. However, the exact mechanism of aggresome formation and clearance is not thoroughly understood. Reports have shown that several proteins including p300, p53, TAU, α-synuclein, SOD, etc. contain intrinsically disordered region (IDR) which has the tendency to form aggresome. To study the nature of aggresome formation and stability of the aggresome, we have chosen Twist1 as a model protein since it has IDR regions. Twist1 is a bHLH transcription factor which plays a major role in epithelial mesenchymal transition (EMT) and shown to interact with HAT domain of p300 and p53. In the present study, we generated several deletion mutants of human Twist1 with different fluorescent tags and delineated the regions responsible for aggresome formation. The Twist1 protein contains two NLS motifs at the N-terminal region. We showed that the deletions of regions spanning the amino acids 30-46 (Twist1Δ30-46) which lacks the first NLS motif form larger and intense aggregates while the deletion of residues from 47 to 100 (Twist1Δ47-100) which lacks the second NLS motif generates smaller and less intense aggregates in the juxta nuclear position. This suggests that both the NLS motifs are needed for the proper nuclear localization of Twist1. The aggresome formation of the Twist1 deletion mutants was confirmed by counterstaining with known aggresome markers: Vimentin, HDAC6, and gamma tubulin and further validated by MG-132 treatment. In addition, it was found that the aggresomes generated by the Twist1Δ30-46 construct are more stable than the aggresome produced by the Twist1Δ47-100 construct as well as the wild-type Twist1 protein. Taken together, our data provide an important understanding on the role of IDR regions on the formation and stability of aggresomes.
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Affiliation(s)
- Gokulapriya Govindarajalu
- Department of Biotechnology, Pondicherry Central University, R. V. Nagar, Kalapet, Pondicherry, 605014, India
| | - Murugan Selvam
- Department of Biotechnology, Pondicherry Central University, R. V. Nagar, Kalapet, Pondicherry, 605014, India
| | - Elango Palchamy
- Translational Gerontology Branch, National Institute ON Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Sudhakar Baluchamy
- Department of Biotechnology, Pondicherry Central University, R. V. Nagar, Kalapet, Pondicherry, 605014, India.
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47
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Oh TR, Kim JH, Cho SK, Ryu MY, Yang SW, Kim WT. AtAIRP2 E3 Ligase Affects ABA and High-Salinity Responses by Stimulating Its ATP1/SDIRIP1 Substrate Turnover. PLANT PHYSIOLOGY 2017; 174:2515-2531. [PMID: 28626006 PMCID: PMC5543955 DOI: 10.1104/pp.17.00467] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/13/2017] [Indexed: 05/20/2023]
Abstract
AtAIRP2 is a cytosolic RING-type E3 ubiquitin ligase that positively regulates an abscisic acid (ABA) response in Arabidopsis (Arabidopsis thaliana). Yeast two-hybrid screening using AtAIRP2 as bait identified ATP1 (AtAIRP2 Target Protein1) as a substrate of AtAIRP2. ATP1 was found to be identical to SDIRIP1, which was reported recently to be a negative factor in ABA signaling and a target protein of the RING E3 ligase SDIR1. Accordingly, ATP1 was renamed ATP1/SDIRIP1. A specific interaction between AtAIRP2 and ATP1/SDIRIP1 and ubiquitination of ATP1/SDIRIP1 by AtAIRP2 were demonstrated in vitro and in planta. The turnover of ATP1/SDIRIP1 was regulated by AtAIRP2 in cell-free degradation and protoplast cotransfection assays. The ABA-mediated germination assay of 35S:ATP1/SDIRIP1-RNAi/atairp2 double mutant progeny revealed that ATP1/SDIRIP1 acts downstream of AtAIRP2. AtAIRP2 and SDIR1 reciprocally complemented the ABA- and salt-insensitive germination phenotypes of sdir1 and atairp2 mutants, respectively, indicating their combinatory roles in seed germination. Subcellular localization and bimolecular fluorescence complementation experiments in the presence of MG132, a 26S proteasome inhibitor, showed that AtAIRP2 and ATP1/SDIRIP1 were colocalized to the cytosolic spherical body, which lies in close proximity to the nucleus, in tobacco (Nicotiana benthamiana) leaf cells. The 26S proteasome subunits RPN12a and RPT1 and the molecular chaperones HSP70 and HSP101 were colocalized to these discrete punctae-like structures. These results raised the possibility that AtAIRP2 and ATP1/SDIRIP1 interact in the cytosolic spherical compartment. Collectively, our data suggest that the down-regulation of ATP1/SDIRIP1 by AtAIRP2 and SDIR1 RING E3 ubiquitin ligases is critical for ABA and high-salinity responses during germination in Arabidopsis.
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Affiliation(s)
- Tae Rin Oh
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Jong Hum Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Seok Keun Cho
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Moon Young Ryu
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Seong Wook Yang
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Woo Taek Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
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48
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Park JH, Jang HR, Lee IY, Oh HK, Choi EJ, Rhim H, Kang S. Amyotrophic lateral sclerosis-related mutant superoxide dismutase 1 aggregates inhibit 14-3-3-mediated cell survival by sequestration into the JUNQ compartment. Hum Mol Genet 2017; 26:3615-3629. [DOI: 10.1093/hmg/ddx250] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 06/26/2017] [Indexed: 12/11/2022] Open
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49
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Abstract
A healthy proteome is essential for cell survival. Protein misfolding is linked to a rapidly expanding list of human diseases, ranging from neurodegenerative diseases to aging and cancer. Many of these diseases are characterized by the accumulation of misfolded proteins in intra- and extracellular inclusions, such as amyloid plaques. The clear link between protein misfolding and disease highlights the need to better understand the elaborate machinery that manages proteome homeostasis, or proteostasis, in the cell. Proteostasis depends on a network of molecular chaperones and clearance pathways involved in the recognition, refolding, and/or clearance of aberrant proteins. Recent studies reveal that an integral part of the cellular management of misfolded proteins is their spatial sequestration into several defined compartments. Here, we review the properties, function, and formation of these compartments. Spatial sequestration plays a central role in protein quality control and cellular fitness and represents a critical link to the pathogenesis of protein aggregation-linked diseases.
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Affiliation(s)
| | - Rahul S Samant
- Department of Biology, Stanford University, Stanford, California 94305; , ,
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, California 94305; , ,
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50
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How and why do toxic conformers of aberrant proteins accumulate during ageing? Essays Biochem 2017; 61:317-324. [DOI: 10.1042/ebc20160085] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 04/04/2017] [Accepted: 04/21/2017] [Indexed: 12/18/2022]
Abstract
Ageing can be defined as a gradual decline in cellular and physical functions accompanied by an increased sensitivity to the environment and risk of death. The increased risk of mortality is causally connected to a gradual, intracellular accumulation of so-called ageing factors, of which damaged and aggregated proteins are believed to be one. Such aggregated proteins also contribute to several age-related neurodegenerative disorders e.g. Alzheimer’s, Parkinson’s, and Huntington’s diseases, highlighting the importance of protein quality control (PQC) in ageing and its associated diseases. PQC consists of two interrelated systems: the temporal control system aimed at refolding, repairing, and/or removing aberrant proteins and their aggregates and the spatial control system aimed at harnessing the potential toxicity of aberrant proteins by sequestering them at specific cellular locations. The accumulation of toxic conformers of aberrant proteins during ageing is often declared to be a consequence of an incapacitated temporal PQC system—i.e. a gradual decline in the activity of chaperones and proteases. Here, we review the current knowledge on PQC in relation to ageing and highlight that the breakdown of both temporal and spatial PQC may contribute to ageing and thus comprise potential targets for therapeutic interventions of the ageing process.
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