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Matheny CJ, Qadota H, Bailey AO, Valdebenito-Silva S, Oberhauser AF, Benian GM. The myosin chaperone UNC-45 has an important role in maintaining the structure and function of muscle sarcomeres during adult aging. Mol Biol Cell 2024; 35:ar98. [PMID: 38809582 DOI: 10.1091/mbc.e23-12-0488] [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: 05/30/2024] Open
Abstract
C. elegans undergo age-dependent declines in muscle organization and function, similar to human sarcopenia. The chaperone UNC-45 is required to fold myosin heads after translation and is likely used for refolding after thermally- or chemically-induced unfolding. UNC-45's TPR region binds HSP-90 and its UCS domain binds myosin heads. We observe early onset sarcopenia when UNC-45 is reduced at the beginning of adulthood. There is sequential decline of HSP-90, UNC-45, and MHC B myosin. A mutation in age-1 delays sarcopenia and loss of HSP-90, UNC-45, and myosin. UNC-45 undergoes age-dependent phosphorylation, and mass spectrometry reveals phosphorylation of six serines and two threonines, seven of which occur in the UCS domain. Additional expression of UNC-45 results in maintenance of MHC B myosin and suppression of A-band disorganization in old animals. Our results suggest that increased expression or activity of UNC-45 might be a strategy for prevention or treatment of sarcopenia.
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Affiliation(s)
| | - Hiroshi Qadota
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Aaron O Bailey
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77550
| | | | - Andres F Oberhauser
- Department of Neurobiology, University of Texas Medical Branch, Galveston, TX 77550
| | - Guy M Benian
- Department of Pathology, Emory University, Atlanta, GA 30322
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2
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Wang H, Sun F. UNC-45A: A potential therapeutic target for malignant tumors. Heliyon 2024; 10:e31276. [PMID: 38803956 PMCID: PMC11128996 DOI: 10.1016/j.heliyon.2024.e31276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 12/31/2023] [Accepted: 05/14/2024] [Indexed: 05/29/2024] Open
Abstract
Uncoordinated mutant number-45 myosin chaperone A (UNC-45A), a protein highly conserved throughout evolution, is ubiquitously expressed in somatic cells. It is correlated with tumorigenesis, proliferation, metastasis, and invasion of multiple malignant tumors. The current understanding of the role of UNC-45A in tumor progression is mainly related to the regulation of non-muscle myosin II (NM-II). However, many studies have suggested that the mechanisms by which UNC-45A is involved in tumor progression are far greater than those of NM-II regulation. UNC-45A can also promote tumor cell proliferation by regulating checkpoint kinase 1 (ChK1) phosphorylation or the transcriptional activity of nuclear receptors, and induces chemoresistance to paclitaxel in tumor cells by destabilizing microtubule activity. In this review, we discuss the recent advances illuminating the role of UNC-45A in tumor progression. We also put forward therapeutic strategies targeting UNC-45A, in the hope of paving the way the development of UNC-45A-targeted therapies for patients with malignant tumors.
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Affiliation(s)
- Hong Wang
- School of Nursing, Binzhou Medical University, Yantai, 264003, PR China
| | - Fude Sun
- Department of Anesthesiology, Yantai Penglai Traditional Chinese Medicine Hospital, Yantai, 265699, PR China
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3
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Lechuga S, Marino-Melendez A, Naydenov NG, Zafar A, Braga-Neto MB, Ivanov AI. Regulation of Epithelial and Endothelial Barriers by Molecular Chaperones. Cells 2024; 13:370. [PMID: 38474334 PMCID: PMC10931179 DOI: 10.3390/cells13050370] [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: 01/05/2024] [Revised: 02/15/2024] [Accepted: 02/16/2024] [Indexed: 03/14/2024] Open
Abstract
The integrity and permeability of epithelial and endothelial barriers depend on the formation of tight junctions, adherens junctions, and a junction-associated cytoskeleton. The establishment of this junction-cytoskeletal module relies on the correct folding and oligomerization of its protein components. Molecular chaperones are known regulators of protein folding and complex formation in different cellular compartments. Mammalian cells possess an elaborate chaperone network consisting of several hundred chaperones and co-chaperones. Only a small part of this network has been linked, however, to the regulation of intercellular adhesions, and the systematic analysis of chaperone functions at epithelial and endothelial barriers is lacking. This review describes the functions and mechanisms of the chaperone-assisted regulation of intercellular junctions. The major focus of this review is on heat shock protein chaperones, their co-chaperones, and chaperonins since these molecules are the focus of the majority of the articles published on the chaperone-mediated control of tissue barriers. This review discusses the roles of chaperones in the regulation of the steady-state integrity of epithelial and vascular barriers as well as the disruption of these barriers by pathogenic factors and extracellular stressors. Since cytoskeletal coupling is essential for junctional integrity and remodeling, chaperone-assisted assembly of the actomyosin cytoskeleton is also discussed.
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Affiliation(s)
- Susana Lechuga
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
| | - Armando Marino-Melendez
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
| | - Nayden G. Naydenov
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
| | - Atif Zafar
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
| | - Manuel B. Braga-Neto
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
- Department of Gastroenterology, Hepatology and Nutrition, Digestive Disease Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Andrei I. Ivanov
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA; (S.L.); (A.M.-M.); (N.G.N.); (A.Z.); (M.B.B.-N.)
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4
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Schiller NR, Almuhanna SA, Hoppe PE. UNC-82/NUAK kinase is required by myosin A, but not myosin B, to assemble and function in the thick filament arms of C. elegans striated muscle. Cytoskeleton (Hoboken) 2023. [PMID: 37983932 DOI: 10.1002/cm.21807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/10/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023]
Abstract
The mechanisms that ensure proper assembly, activity, and turnover of myosin II filaments are fundamental to a diverse range of cellular processes. In Caenorhabditis elegans striated muscle, thick filaments contain two myosins that are functionally distinct and spatially segregated. Using transgenic double mutants, we demonstrate that the ability of increased myosin A expression to restore muscle structure and movement in myosin B mutants requires UNC-82/NUAK kinase activity. Myosin B function appears unaffected in the kinase-impaired unc-82(e1220) mutant: the recessive antimorphic effects on early assembly of paramyosin and myosin A in this mutant are counteracted by increased myosin B expression and exacerbated by loss of myosin B. Using chimeric myosins and motility assays, we mapped the region of myosin A that requires UNC-82 activity to a 531-amino-acid region of the coiled-coil rod. This region includes the 264-amino-acid Region 1, which is sufficient in chimeric myosins to rescue the essential filament-initiation function of myosin A, as well as two sites that interact with myosin head domains in the Interacting Heads Motif. A specific physical interaction between myosin A and UNC-82::GFP is supported by GFP labeling of ectopic myosin A filaments but not thin filaments. We hypothesize that UNC-82 regulates assembly competence of myosin A during parallel assembly in the filament arms.
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Affiliation(s)
- NaTasha R Schiller
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan, USA
- Biology Department, Wingate University, Wingate, North Carolina, USA
| | - Sarah A Almuhanna
- Clinical Laboratory Sciences, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia
| | - Pamela E Hoppe
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan, USA
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5
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Lu SHA, Wu YH, Su LY, Hsu ZT, Weng TH, Wang HY, Yu C, Hsu PWC, Tsai SY. Cardiac myofibrillogenesis is spatiotemporally modulated by the molecular chaperone UNC45B. Stem Cell Reports 2023:S2213-6711(23)00184-4. [PMID: 37295424 PMCID: PMC10362501 DOI: 10.1016/j.stemcr.2023.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/09/2023] [Accepted: 05/09/2023] [Indexed: 06/12/2023] Open
Abstract
Sarcomeres are fundamental to cardiac muscle contraction. Their impairment can elicit cardiomyopathies, leading causes of death worldwide. However, the molecular mechanism underlying sarcomere assembly remains obscure. We used human embryonic stem cell (hESC)-derived cardiomyocytes (CMs) to reveal stepwise spatiotemporal regulation of core cardiac myofibrillogenesis-associated proteins. We found that the molecular chaperone UNC45B is highly co-expressed with KINDLIN2 (KIND2), a marker of protocostameres, and later its distribution overlaps with that of muscle myosin MYH6. UNC45B-knockout CMs display essentially no contractility. Our phenotypic analyses further reveal that (1) binding of Z line anchor protein ACTN2 to protocostameres is perturbed because of impaired protocostamere formation, resulting in ACTN2 accumulation; (2) F-ACTIN polymerization is suppressed; and (3) MYH6 becomes degraded, so it cannot replace non-muscle myosin MYH10. Our mechanistic study demonstrates that UNC45B mediates protocostamere formation by regulating KIND2 expression. Thus, we show that UNC45B modulates cardiac myofibrillogenesis by interacting spatiotemporally with various proteins.
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Affiliation(s)
- Serena Huei-An Lu
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Yi-Hsuan Wu
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Liang-Yu Su
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Zi-Ting Hsu
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Tzu-Han Weng
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Hsin-Yu Wang
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Chiao Yu
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Paul Wei-Che Hsu
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan
| | - Su-Yi Tsai
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei 10617, Taiwan; Genome and Systems Biology Degree Program, National Taiwan University, Taipei 10617, Taiwan.
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6
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Velayuthan LP, Moretto L, Tågerud S, Ušaj M, Månsson A. Virus-free transfection, transient expression, and purification of human cardiac myosin in mammalian muscle cells for biochemical and biophysical assays. Sci Rep 2023; 13:4101. [PMID: 36907906 PMCID: PMC10008826 DOI: 10.1038/s41598-023-30576-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/27/2023] [Indexed: 03/13/2023] Open
Abstract
Myosin expression and purification is important for mechanistic insights into normal function and mutation induced changes. The latter is particularly important for striated muscle myosin II where mutations cause several debilitating diseases. However, the heavy chain of this myosin is challenging to express and the standard protocol, using C2C12 cells, relies on viral infection. This is time and work intensive and associated with infrastructural demands and biological hazards, limiting widespread use and hampering fast generation of a wide range of mutations. We here develop a virus-free method to overcome these challenges. We use this system to transfect C2C12 cells with the motor domain of the human cardiac myosin heavy chain. After optimizing cell transfection, cultivation and harvesting conditions, we functionally characterized the expressed protein, co-purified with murine essential and regulatory light chains. The gliding velocity (1.5-1.7 µm/s; 25 °C) in the in vitro motility assay as well as maximum actin activated catalytic activity (kcat; 8-9 s-1) and actin concentration for half maximal activity (KATPase; 70-80 µM) were similar to those found previously using virus based infection. The results should allow new types of studies, e.g., screening of a wide range of mutations to be selected for further characterization.
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Affiliation(s)
- Lok Priya Velayuthan
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden
| | - Luisa Moretto
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden
| | - Sven Tågerud
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden
| | - Marko Ušaj
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden.
| | - Alf Månsson
- Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden.
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7
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Kutzner CE, Bauer KC, Hoppe T. A ubiquitin fusion reporter to monitor muscle proteostasis in C. elegans. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000824. [PMID: 37159574 PMCID: PMC10163378 DOI: 10.17912/micropub.biology.000824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/11/2023] [Accepted: 04/20/2023] [Indexed: 05/11/2023]
Abstract
Muscle is a highly dynamic tissue in which a variety of folding and degradation processes are active to maintain protein homeostasis (proteostasis) and functionality. The muscle-specific chaperone UNC-45 folds the motor protein myosin and assembles it into myofilaments. Malfunction of this chaperone leads to misfolding of myosin, disorganization of myofilaments, and degradation of misfolded myosin molecules by the proteasome. Here, we present a new muscle-specific ubiquitin fusion degradation (UFD) model substrate in C. elegans that helps clarify how UNC-45 dysfunction affects muscle proteostasis.
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Affiliation(s)
- Carl Elias Kutzner
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), Cologne, Germany
- Center for Molecular Medicine (CMMC), Cologne, Germany
| | - Karen Carolyn Bauer
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), Cologne, Germany
| | - Thorsten Hoppe
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), Cologne, Germany
- Center for Molecular Medicine (CMMC), Cologne, Germany
- Correspondence to: Thorsten Hoppe (
)
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8
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Odunuga OO, Oberhauser AF. Beyond Chaperoning: UCS Proteins Emerge as Regulators of Myosin-Mediated Cellular Processes. Subcell Biochem 2023; 101:189-211. [PMID: 36520308 DOI: 10.1007/978-3-031-14740-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The UCS (UNC-45/CRO1/She4p) family of proteins has emerged as chaperones specific for the folding, assembly, and function of myosin. UCS proteins participate in various myosin-dependent cellular processes including myofibril organization and muscle functions, cell differentiation, striated muscle development, cytokinesis, and endocytosis. Mutations in the genes that code for UCS proteins cause serious defects in myosin-dependent cellular processes. UCS proteins that contain an N-terminal tetratricopeptide repeat (TPR) domain are called UNC-45. Vertebrates usually possess two variants of UNC-45, the ubiquitous general-cell UNC-45 (UNC-45A) and the striated muscle UNC-45 (UNC-45B), which is exclusively expressed in skeletal and cardiac muscles. Except for the TPR domain in UNC-45, UCS proteins comprise of several irregular armadillo (ARM) repeats that are organized into a central domain, a neck region, and the canonical C-terminal UCS domain that functions as the chaperoning module. With or without TPR, UCS proteins form linear oligomers that serve as scaffolds that mediate myosin folding, organization into myofibrils, repair, and motility. This chapter reviews emerging functions of these proteins with a focus on UNC-45 as a dedicated chaperone for folding, assembly, and function of myosin at protein and potentially gene levels. Recent experimental evidences strongly support UNC-45 as an absolute regulator of myosin, with each domain of the chaperone playing different but complementary roles during the folding, assembly, and function of myosin, as well as recruiting Hsp90 as a co-chaperone to optimize key steps. It is becoming increasingly clear that UNC-45 also regulates the transcription of several genes involved in myosin-dependent cellular processes.
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Affiliation(s)
- Odutayo O Odunuga
- Department of Chemistry and Biochemistry, Stephen F. Austin State University, Nacogdoches, TX, USA.
| | - Andres F Oberhauser
- Department of Neuroscience, Cell Biology, & Anatomy, The University of Texas Medical Branch, Galveston, TX, USA.
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9
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Johnson CA, Behbehani R, Buss F. Unconventional Myosins from Caenorhabditis elegans as a Probe to Study Human Orthologues. Biomolecules 2022; 12:biom12121889. [PMID: 36551317 PMCID: PMC9775386 DOI: 10.3390/biom12121889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Unconventional myosins are a superfamily of actin-based motor proteins that perform a number of roles in fundamental cellular processes, including (but not limited to) intracellular trafficking, cell motility, endocytosis, exocytosis and cytokinesis. 40 myosins genes have been identified in humans, which belong to different 12 classes based on their domain structure and organisation. These genes are widely expressed in different tissues, and mutations leading to loss of function are associated with a wide variety of pathologies while over-expression often results in cancer. Caenorhabditis elegans (C. elegans) is a small, free-living, non-parasitic nematode. ~38% of the genome of C. elegans has predicted orthologues in the human genome, making it a valuable tool to study the function of human counterparts and human diseases. To date, 8 unconventional myosin genes have been identified in the nematode, from 6 different classes with high homology to human paralogues. The hum-1 and hum-5 (heavy chain of an unconventional myosin) genes encode myosin of class I, hum-2 of class V, hum-3 and hum-8 of class VI, hum-6 of class VII and hum-7 of class IX. The hum-4 gene encodes a high molecular mass myosin (307 kDa) that is one of the most highly divergent myosins and is a member of class XII. Mutations in many of the human orthologues are lethal, indicating their essential properties. However, a functional characterisation for many of these genes in C. elegans has not yet been performed. This article reviews the current knowledge of unconventional myosin genes in C. elegans and explores the potential use of the nematode to study the function and regulation of myosin motors to provide valuable insights into their role in diseases.
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10
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The genetics of monogenic intestinal epithelial disorders. Hum Genet 2022; 142:613-654. [PMID: 36422736 PMCID: PMC10182130 DOI: 10.1007/s00439-022-02501-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 10/23/2022] [Indexed: 11/27/2022]
Abstract
Monogenic intestinal epithelial disorders, also known as congenital diarrheas and enteropathies (CoDEs), are a group of rare diseases that result from mutations in genes that primarily affect intestinal epithelial cell function. Patients with CoDE disorders generally present with infantile-onset diarrhea and poor growth, and often require intensive fluid and nutritional management. CoDE disorders can be classified into several categories that relate to broad areas of epithelial function, structure, and development. The advent of accessible and low-cost genetic sequencing has accelerated discovery in the field with over 45 different genes now associated with CoDE disorders. Despite this increasing knowledge in the causal genetics of disease, the underlying cellular pathophysiology remains incompletely understood for many disorders. Consequently, clinical management options for CoDE disorders are currently limited and there is an urgent need for new and disorder-specific therapies. In this review, we provide a general overview of CoDE disorders, including a historical perspective of the field and relationship to other monogenic disorders of the intestine. We describe the genetics, clinical presentation, and known pathophysiology for specific disorders. Lastly, we describe the major challenges relating to CoDE disorders, briefly outline key areas that need further study, and provide a perspective on the future genetic and therapeutic landscape.
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11
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Piper PW, Scott JE, Millson SH. UCS Chaperone Folding of the Myosin Head: A Function That Evolved before Animals and Fungi Diverged from a Common Ancestor More than a Billion Years Ago. Biomolecules 2022; 12:biom12081028. [PMID: 35892339 PMCID: PMC9331494 DOI: 10.3390/biom12081028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/18/2022] [Accepted: 07/20/2022] [Indexed: 12/04/2022] Open
Abstract
The folding of the myosin head often requires a UCS (Unc45, Cro1, She4) domain-containing chaperone. Worms, flies, and fungi have just a single UCS protein. Vertebrates have two; one (Unc45A) which functions primarily in non-muscle cells and another (Unc45B) that is essential for establishing and maintaining the contractile apparatus of cardiac and skeletal muscles. The domain structure of these proteins suggests that the UCS function evolved before animals and fungi diverged from a common ancestor more than a billion years ago. UCS proteins of metazoans and apicomplexan parasites possess a tetratricopeptide repeat (TPR), a domain for direct binding of the Hsp70/Hsp90 chaperones. This, however, is absent in the UCS proteins of fungi and largely nonessential for the UCS protein function in Caenorhabditis elegans and zebrafish. The latter part of this review focusses on the TPR-deficient UCS proteins of fungi. While these are reasonably well studied in yeasts, there is little precise information as to how they might engage in interactions with the Hsp70/Hsp90 chaperones or might assist in myosin operations during the hyphal growth of filamentous fungi.
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Affiliation(s)
- Peter William Piper
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
- Correspondence: (P.W.P.); (S.H.M.)
| | | | - Stefan Heber Millson
- School of Life Sciences, University of Lincoln, Lincoln LN6 7DL, UK;
- Correspondence: (P.W.P.); (S.H.M.)
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12
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Lechuga S, Cartagena‐Rivera AX, Khan A, Crawford BI, Narayanan V, Conway DE, Lehtimäki J, Lappalainen P, Rieder F, Longworth MS, Ivanov AI. A myosin chaperone, UNC-45A, is a novel regulator of intestinal epithelial barrier integrity and repair. FASEB J 2022; 36:e22290. [PMID: 35344227 PMCID: PMC9044500 DOI: 10.1096/fj.202200154r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/15/2022] [Accepted: 03/18/2022] [Indexed: 01/01/2023]
Abstract
The actomyosin cytoskeleton serves as a key regulator of the integrity and remodeling of epithelial barriers by controlling assembly and functions of intercellular junctions and cell-matrix adhesions. Although biochemical mechanisms that regulate the activity of non-muscle myosin II (NM-II) in epithelial cells have been extensively investigated, little is known about assembly of the contractile myosin structures at the epithelial adhesion sites. UNC-45A is a cytoskeletal chaperone that is essential for proper folding of NM-II heavy chains and myofilament assembly. We found abundant expression of UNC-45A in human intestinal epithelial cell (IEC) lines and in the epithelial layer of the normal human colon. Interestingly, protein level of UNC-45A was decreased in colonic epithelium of patients with ulcerative colitis. CRISPR/Cas9-mediated knock-out of UNC-45A in HT-29cf8 and SK-CO15 IEC disrupted epithelial barrier integrity, impaired assembly of epithelial adherence and tight junctions and attenuated cell migration. Consistently, decreased UNC-45 expression increased permeability of the Drosophila gut in vivo. The mechanisms underlying barrier disruptive and anti-migratory effects of UNC-45A depletion involved disorganization of the actomyosin bundles at epithelial junctions and the migrating cell edge. Loss of UNC-45A also decreased contractile forces at apical junctions and matrix adhesions. Expression of deletion mutants revealed roles for the myosin binding domain of UNC-45A in controlling IEC junctions and motility. Our findings uncover a novel mechanism that regulates integrity and restitution of the intestinal epithelial barrier, which may be impaired during mucosal inflammation.
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Affiliation(s)
- Susana Lechuga
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Alexander X. Cartagena‐Rivera
- Section on MechanobiologyNational Institute of Biomedical Imaging and BioengineeringNational Institutes of HealthBethesdaMarylandUSA
| | - Afshin Khan
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Bert I. Crawford
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Vani Narayanan
- Department of Biomedical EngineeringVirginia Commonwealth UniversityRichmondVirginiaUSA
| | - Daniel E. Conway
- Department of Biomedical EngineeringVirginia Commonwealth UniversityRichmondVirginiaUSA
| | - Jaakko Lehtimäki
- Institute of Biotechnology and Helsinki Institute of Life SciencesUniversity of HelsinkiHelsinkiFinland
| | - Pekka Lappalainen
- Institute of Biotechnology and Helsinki Institute of Life SciencesUniversity of HelsinkiHelsinkiFinland
| | - Florian Rieder
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA,Department of Gastroenterology, Hepatology and Nutrition, Digestive Diseases and Surgery InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Michelle S. Longworth
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA
| | - Andrei I. Ivanov
- Department of Inflammation and ImmunityLerner Research InstituteCleveland Clinic FoundationClevelandOhioUSA
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13
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Goulet O, Pigneur B, Charbit-Henrion F. Congenital enteropathies involving defects in enterocyte structure or differentiation. Best Pract Res Clin Gastroenterol 2022; 56-57:101784. [PMID: 35331396 DOI: 10.1016/j.bpg.2021.101784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/15/2021] [Accepted: 12/22/2021] [Indexed: 01/31/2023]
Abstract
Congenital enteropathies (CE) are a group of rare inherited diseases with a typical onset early in life. They involve defects in enterocyte structure or differentiation. They can cause a severe condition of intestinal failure (IF). The diagnostic approach is based first on clinical presentation (consanguinity, prenatal expression, polyhydramnios, early neonatal onset, aspect of stools, persistence at bowel rest, associated extra-digestive manifestations….) and histo-pathological analyses. These rare intestinal diseases cause protracted diarrhea that might resolve, for a few, with a dietetic approach. However, protracted or permanent IF may require long term parenteral nutrition and, in limited cases, intestinal transplantation. With the progresses in both clinical nutrition and genetics, many of these CE are nowadays associated with recognized gene mutations. It improved our knowledge and the understanding in the patho-physiology of these diseases, thus, leading potentially to therapeutic perspectives. These review cover most of the early onset CE and excludes the immune related diarrhea.
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Affiliation(s)
- Olivier Goulet
- Division of Paediatric Gastroenterology Hepatology and Nutrition, University Paris-Centre, Hôpital Necker-Enfants Malades, 149, Rue de Sèvres, 75743, PARIS Cedex 15, France.
| | - Bénédicte Pigneur
- Division of Paediatric Gastroenterology Hepatology and Nutrition, University Paris-Centre, Hôpital Necker-Enfants Malades, 149, Rue de Sèvres, 75743, PARIS Cedex 15, France
| | - Fabienne Charbit-Henrion
- Department of Genetics, Hôpital Necker-Enfants Malades, 149, Rue de Sèvres, 75743, PARIS Cedex 15, France
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14
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Moncrief T, Matheny CJ, Gaziova I, Miller JM, Qadota H, Benian GM, Oberhauser AF. Mutations in conserved residues of the myosin chaperone UNC-45 result in both reduced stability and chaperoning activity. Protein Sci 2021; 30:2221-2232. [PMID: 34515376 DOI: 10.1002/pro.4180] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 08/17/2021] [Accepted: 09/02/2021] [Indexed: 01/22/2023]
Abstract
Proper muscle development and function depend on myosin being properly folded and integrated into the thick filament structure. For this to occur the myosin chaperone UNC-45, or UNC-45B, must be present and able to chaperone myosin. Here we use a combination of in vivo C. elegans experiments and in vitro biophysical experiments to analyze the effects of six missense mutations in conserved regions of UNC-45/UNC-45B. We found that the phenotype of paralysis and disorganized thick filaments in 5/6 of the mutant nematode strains can likely be attributed to both reduced steady state UNC-45 protein levels and reduced chaperone activity. Interestingly, the biophysical assays performed on purified proteins show that all of the mutations result in reduced myosin chaperone activity but not overall protein stability. This suggests that these mutations only cause protein instability in the in vivo setting and that these conserved regions may be involved in UNC-45 protein stability/regulation via posttranslational modifications, protein-protein interactions, or some other unknown mechanism.
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Affiliation(s)
- Taylor Moncrief
- Department of Neuroscience, Cell Biology and Anatomy, Emory University, Atlanta, Georgia
| | | | - Ivana Gaziova
- Department of Neuroscience, Cell Biology and Anatomy, Emory University, Atlanta, Georgia
| | - John M Miller
- Department of Biochemistry and Molecular Biology, Emory University, Atlanta, Georgia
| | - Hiroshi Qadota
- Department of Pathology, Emory University, Atlanta, Georgia
| | - Guy M Benian
- Department of Pathology, Emory University, Atlanta, Georgia
| | - Andres F Oberhauser
- Department of Neuroscience, Cell Biology and Anatomy, Emory University, Atlanta, Georgia.,Department of Biochemistry and Molecular Biology, Emory University, Atlanta, Georgia.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas
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15
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Tang H, Cui M, Han M. Fatty acids impact sarcomere integrity through myristoylation and ER homeostasis. Cell Rep 2021; 36:109539. [PMID: 34407398 PMCID: PMC8404530 DOI: 10.1016/j.celrep.2021.109539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 06/04/2021] [Accepted: 07/26/2021] [Indexed: 01/01/2023] Open
Abstract
Decreased ability to maintain tissue integrity is critically involved in aging and degenerative diseases. Fatty acid (FA) metabolism has a profound impact on animal development and tissue maintenance, but our understanding of the underlying mechanisms is limited. We investigated whether and how FA abundance affects muscle integrity using Caenorhabditis elegans. We show that reducing the overall FA level by blocking FA biosynthesis or inhibiting protein myristoylation leads to disorganization of sarcomere structure and adult-onset paralysis. Further analysis indicates that myristoylation of two ARF guanosine triphosphatases (GTPases) critically mediates the effect of FA deficiency on sarcomere integrity through inducing endoplasmic reticulum (ER) stress and ER unfolded protein response (UPRER), which in turn leads to reduction of the level of sarcomere component PINCH and myosin disorganization. We thus present a mechanism that links FA signal, protein myristoylation, and ER homeostasis with muscle integrity, which provides valuable insights into the regulatory role of nutrients and ER homeostasis in muscle maintenance. Tang et al. show that fatty acid deficiency causes defects in muscle integrity in the nematode C. elegans and such an impact is mediated by deficiency of lipid modification of specific proteins in the muscle that in turn triggers ER stress and muscle disorganization. The results reveal the regulatory roles of fatty acids and ER homeostasis in muscle maintenance.
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Affiliation(s)
- Hongyun Tang
- Department of MCDB, University of Colorado Boulder, Boulder, CO 80309, USA; Key Laboratory of Growth Regulation and Transformation Research of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou 310024, Zhejiang Province, China; Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou 310024, Zhejiang Province, China
| | - Mingxue Cui
- Department of MCDB, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Min Han
- Department of MCDB, University of Colorado Boulder, Boulder, CO 80309, USA.
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16
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Höhfeld J, Benzing T, Bloch W, Fürst DO, Gehlert S, Hesse M, Hoffmann B, Hoppe T, Huesgen PF, Köhn M, Kolanus W, Merkel R, Niessen CM, Pokrzywa W, Rinschen MM, Wachten D, Warscheid B. Maintaining proteostasis under mechanical stress. EMBO Rep 2021; 22:e52507. [PMID: 34309183 PMCID: PMC8339670 DOI: 10.15252/embr.202152507] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 12/11/2022] Open
Abstract
Cell survival, tissue integrity and organismal health depend on the ability to maintain functional protein networks even under conditions that threaten protein integrity. Protection against such stress conditions involves the adaptation of folding and degradation machineries, which help to preserve the protein network by facilitating the refolding or disposal of damaged proteins. In multicellular organisms, cells are permanently exposed to stress resulting from mechanical forces. Yet, for long time mechanical stress was not recognized as a primary stressor that perturbs protein structure and threatens proteome integrity. The identification and characterization of protein folding and degradation systems, which handle force-unfolded proteins, marks a turning point in this regard. It has become apparent that mechanical stress protection operates during cell differentiation, adhesion and migration and is essential for maintaining tissues such as skeletal muscle, heart and kidney as well as the immune system. Here, we provide an overview of recent advances in our understanding of mechanical stress protection.
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Affiliation(s)
- Jörg Höhfeld
- Institute for Cell BiologyRheinische Friedrich‐Wilhelms University BonnBonnGermany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC)University of CologneCologneGermany
| | - Wilhelm Bloch
- Institute of Cardiovascular Research and Sports MedicineGerman Sport UniversityCologneGermany
| | - Dieter O Fürst
- Institute for Cell BiologyRheinische Friedrich‐Wilhelms University BonnBonnGermany
| | - Sebastian Gehlert
- Institute of Cardiovascular Research and Sports MedicineGerman Sport UniversityCologneGermany
- Department for the Biosciences of SportsInstitute of Sports ScienceUniversity of HildesheimHildesheimGermany
| | - Michael Hesse
- Institute of Physiology I, Life & Brain CenterMedical FacultyRheinische Friedrich‐Wilhelms UniversityBonnGermany
| | - Bernd Hoffmann
- Institute of Biological Information Processing, IBI‐2: MechanobiologyForschungszentrum JülichJülichGermany
| | - Thorsten Hoppe
- Institute for GeneticsCologne Excellence Cluster on Cellular Stress Responses in Aging‐Associated Diseases (CECAD) and CMMCUniversity of CologneCologneGermany
| | - Pitter F Huesgen
- Central Institute for Engineering, Electronics and Analytics, ZEA3Forschungszentrum JülichJülichGermany
- CECADUniversity of CologneCologneGermany
| | - Maja Köhn
- Institute of Biology IIIFaculty of Biology, and Signalling Research Centres BIOSS and CIBSSAlbert‐Ludwigs‐University FreiburgFreiburgGermany
| | - Waldemar Kolanus
- LIMES‐InstituteRheinische Friedrich‐Wilhelms University BonnBonnGermany
| | - Rudolf Merkel
- Institute of Biological Information Processing, IBI‐2: MechanobiologyForschungszentrum JülichJülichGermany
| | - Carien M Niessen
- Department of Dermatology and CECADUniversity of CologneCologneGermany
| | | | - Markus M Rinschen
- Department of Biomedicine and Aarhus Institute of Advanced StudiesAarhus UniversityAarhusDenmark
- Department of MedicineUniversity Medical Center Hamburg‐EppendorfHamburgGermany
| | - Dagmar Wachten
- Institute of Innate ImmunityUniversity Hospital BonnBonnGermany
| | - Bettina Warscheid
- Institute of Biology IIFaculty of Biology, and Signalling Research Centres BIOSS and CIBSSAlbert‐Ludwigs‐University FreiburgFreiburgGermany
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17
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Karunendiran A, Nguyen CT, Barzda V, Stewart BA. Disruption of Drosophila larval muscle structure and function by UNC45 knockdown. BMC Mol Cell Biol 2021; 22:38. [PMID: 34256704 PMCID: PMC8278773 DOI: 10.1186/s12860-021-00373-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 06/06/2021] [Indexed: 11/10/2022] Open
Abstract
Background Proper muscle function is heavily dependent on highly ordered protein complexes. UNC45 is a USC (named since this region is shared by three proteins UNC45/CRO1/She4P) chaperone that is necessary for myosin incorporation into the thick filaments. UNC45 is expressed throughout the entire Drosophila life cycle and it has been shown to be important during late embryogenesis when initial muscle development occurs. However, the effects of UNC45 manipulation at later developmental times, after muscle development, have not yet been studied. Main results UNC45 was knocked down with RNAi in a manner that permitted survival to the pupal stage, allowing for characterization of sarcomere organization in the well-studied third instar larvae. Second harmonic generation (SHG) microscopy revealed changes in the striated pattern of body wall muscles as well as a reduction of signal intensity. This observation was confirmed with immunofluorescence and electron microscopy imaging, showing diminished UNC45 signal and disorganization of myosin and z-disk proteins. Concomitant alterations in both synaptic physiology and locomotor function were also found. Both nerve-stimulated response and spontaneous vesicle release were negatively affected, while larval movement was impaired. Conclusions This study highlights the dependency of normal sarcomere structure on UNC45 expression. We confirm the known role of UNC45 for myosin localization and further show the I-Z-I complex is also disrupted. This suggests a broad need for UNC45 to maintain sarcomere integrity. Newly discovered changes in synaptic physiology reveal the likely presence of a homeostatic response to partially maintain synaptic strength and muscle function.
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Affiliation(s)
- Abiramy Karunendiran
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Christine T Nguyen
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Virginijus Barzda
- Department of Physics, University of Toronto, Toronto, ON, Canada.,Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Bryan A Stewart
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada. .,Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada.
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18
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Habicht J, Mooneyham A, Hoshino A, Shetty M, Zhang X, Emmings E, Yang Q, Coombes C, Gardner MK, Bazzaro M. UNC-45A breaks the microtubule lattice independently of its effects on non-muscle myosin II. J Cell Sci 2021; 134:jcs.248815. [PMID: 33262310 DOI: 10.1242/jcs.248815] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 11/18/2020] [Indexed: 12/13/2022] Open
Abstract
In invertebrates, UNC-45 regulates myosin stability and functions. Vertebrates have two distinct isoforms of the protein: UNC-45B, expressed in muscle cells only, and UNC-45A, expressed in all cells and implicated in regulating both non-muscle myosin II (NMII)- and microtubule (MT)-associated functions. Here, we show that, in vitro and in human and rat cells, UNC-45A binds to the MT lattice, leading to MT bending, breakage and depolymerization. Furthermore, we show that UNC-45A destabilizes MTs independent of its C-terminal NMII-binding domain and even in the presence of the NMII inhibitor blebbistatin. These findings identified UNC-45A as a novel type of MT-severing protein with a dual non-mutually exclusive role in regulating NMII activity and MT stability. Because many human diseases, from cancer to neurodegenerative diseases, are caused by or associated with deregulation of MT stability, our findings have profound implications in the biology of MTs, as well as the biology of human diseases and possible therapeutic implications for their treatment.This article has an associated First Person interview with the joint first authors of the paper.
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Affiliation(s)
- Juri Habicht
- Bradenburg Medical School - Theodor Fontane, Neuruppin 16816, Germany.,Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ashley Mooneyham
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Asumi Hoshino
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mihir Shetty
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Xiaonan Zhang
- Bradenburg Medical School - Theodor Fontane, Neuruppin 16816, Germany.,Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
| | - Edith Emmings
- Bradenburg Medical School - Theodor Fontane, Neuruppin 16816, Germany
| | - Qing Yang
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Courtney Coombes
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Melissa K Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Martina Bazzaro
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN 55455, USA
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19
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Under construction: The dynamic assembly, maintenance, and degradation of the cardiac sarcomere. J Mol Cell Cardiol 2020; 148:89-102. [PMID: 32920010 DOI: 10.1016/j.yjmcc.2020.08.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/20/2020] [Accepted: 08/22/2020] [Indexed: 12/11/2022]
Abstract
The sarcomere is the basic contractile unit of striated muscle and is a highly ordered protein complex with the actin and myosin filaments at its core. Assembling the sarcomere constituents into this organized structure in development, and with muscle growth as new sarcomeres are built, is a complex process coordinated by numerous factors. Once assembled, the sarcomere requires constant maintenance as its continuous contraction is accompanied by elevated mechanical, thermal, and oxidative stress, which predispose proteins to misfolding and toxic aggregation. To prevent protein misfolding and maintain sarcomere integrity, the sarcomere is monitored by an assortment of protein quality control (PQC) mechanisms. The need for effective PQC is heightened in cardiomyocytes which are terminally differentiated and must survive for many years while preserving optimal mechanical output. To prevent toxic protein aggregation, molecular chaperones stabilize denatured sarcomere proteins and promote their refolding. However, when old and misfolded proteins cannot be salvaged by chaperones, they must be recycled via degradation pathways: the calpain and ubiquitin-proteasome systems, which operate under basal conditions, and the stress-responsive autophagy-lysosome pathway. Mutations to and deficiency of the molecular chaperones and associated factors charged with sarcomere maintenance commonly lead to sarcomere structural disarray and the progression of heart disease, highlighting the necessity of effective sarcomere PQC for maintaining cardiac function. This review focuses on the dynamic regulation of assembly and turnover at the sarcomere with an emphasis on the chaperones involved in these processes and describes the alterations to chaperones - through mutations and deficient expression - implicated in disease progression to heart failure.
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20
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Mutational Analysis of the Structure and Function of the Chaperoning Domain of UNC-45B. Biophys J 2020; 119:780-791. [PMID: 32755562 DOI: 10.1016/j.bpj.2020.07.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/29/2022] Open
Abstract
UNC-45B is a multidomain molecular chaperone that is essential for the proper folding and assembly of myosin into muscle thick filaments in vivo. It has previously been demonstrated that the UCS domain is responsible for the chaperone-like properties of the UNC-45B. To better understand the chaperoning function of the UCS domain of the UNC-45B chaperone, we engineered mutations designed to 1) disrupt chaperone-client interactions by removing and altering the structure of a putative client-interacting loop and 2) disrupt chaperone-client interactions by changing highly conserved residues in a putative client-binding groove. We tested the effect of these mutations by using a, to our knowledge, novel combination of complementary biophysical assays (circular dichroism, chaperone activity, and small-angle x-ray scattering) and in vivo tools (Caenorhabditis elegans sarcomere structure). Removing the putative client-binding loop altered the secondary structure of the UCS domain (by decreasing the α-helix content), leading to a significant change in its solution conformation and a reduced chaperoning function. Additionally, we found that mutating several conserved residues in the putative client-binding groove did not alter the UCS domain secondary structure or structural stability but reduced its chaperoning activity. In vivo, these groove mutations were found to significantly alter the structure and organization of C. elegans sarcomeres. Furthermore, we tested the effect of R805W, a mutation distant from the putative client-binding region, which in humans, has been known to cause congenital and infantile cataracts. Our in vivo data show that, to our surprise, the R805W mutation appeared to have the most drastic detrimental effect on the structure and organization of the worm sarcomeres, indicating a crucial role of R805 in UCS-client interactions. Hence, our experimental approach combining biophysical and biological tools facilitates the study of myosin-chaperone interactions in mechanistic detail.
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21
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Prill K, Carlisle C, Stannard M, Windsor Reid PJ, Pilgrim DB. Myomesin is part of an integrity pathway that responds to sarcomere damage and disease. PLoS One 2019; 14:e0224206. [PMID: 31644553 PMCID: PMC6808450 DOI: 10.1371/journal.pone.0224206] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 10/08/2019] [Indexed: 12/17/2022] Open
Abstract
The structure and function of the sarcomere of striated muscle is well studied but the steps of sarcomere assembly and maintenance remain under-characterized. With the aid of chaperones and factors of the protein quality control system, muscle proteins can be folded and assembled into the contractile apparatus of the sarcomere. When sarcomere assembly is incomplete or the sarcomere becomes damaged, suites of chaperones and maintenance factors respond to repair the sarcomere. Here we show evidence of the importance of the M-line proteins, specifically myomesin, in the monitoring of sarcomere assembly and integrity in previously characterized zebrafish muscle mutants. We show that myomesin is one of the last proteins to be incorporated into the assembling sarcomere, and that in skeletal muscle, its incorporation requires connections with both titin and myosin. In diseased zebrafish sarcomeres, myomesin1a shows an early increase of gene expression, hours before chaperones respond to damaged muscle. We found that myomesin expression is also more specific to sarcomere damage than muscle creatine kinase, and our results and others support the use of myomesin assays as an early, specific, method of detecting muscle damage.
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Affiliation(s)
- Kendal Prill
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Casey Carlisle
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Megan Stannard
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | | | - David B. Pilgrim
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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22
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Hellerschmied D, Lehner A, Franicevic N, Arnese R, Johnson C, Vogel A, Meinhart A, Kurzbauer R, Deszcz L, Gazda L, Geeves M, Clausen T. Molecular features of the UNC-45 chaperone critical for binding and folding muscle myosin. Nat Commun 2019; 10:4781. [PMID: 31636255 PMCID: PMC6803673 DOI: 10.1038/s41467-019-12667-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 09/21/2019] [Indexed: 12/16/2022] Open
Abstract
Myosin is a motor protein that is essential for a variety of processes ranging from intracellular transport to muscle contraction. Folding and assembly of myosin relies on a specific chaperone, UNC-45. To address its substrate-targeting mechanism, we reconstitute the interplay between Caenorhabditis elegans UNC-45 and muscle myosin MHC-B in insect cells. In addition to providing a cellular chaperone assay, the established system enabled us to produce large amounts of functional muscle myosin, as evidenced by a biochemical and structural characterization, and to directly monitor substrate binding to UNC-45. Data from in vitro and cellular chaperone assays, together with crystal structures of binding-deficient UNC-45 mutants, highlight the importance of utilizing a flexible myosin-binding domain. This so-called UCS domain can adopt discrete conformations to efficiently bind and fold substrate. Moreover, our data uncover the molecular basis of temperature-sensitive UNC-45 mutations underlying one of the most prominent motility defects in C. elegans. Myosin, a motor protein essential for intracellular transport to muscle contraction, requires a chaperone UNC-45 for folding and assembly. Here authors use in vitro reconstitution and structural biology to characterize the interplay between UNC-45 and muscle myosin MHC-B.
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Affiliation(s)
- Doris Hellerschmied
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria. .,Faculty of Biology, Center of Medical Biotechnology, University Duisburg-Essen, Essen, Germany.
| | | | - Nina Franicevic
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Renato Arnese
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Chloe Johnson
- School of Biosciences, University of Kent, Canterbury, UK
| | - Antonia Vogel
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Anton Meinhart
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Robert Kurzbauer
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Luiza Deszcz
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Linn Gazda
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Michael Geeves
- School of Biosciences, University of Kent, Canterbury, UK
| | - Tim Clausen
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria. .,Medical University Vienna, Vienna, Austria.
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23
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Mooneyham A, Iizuka Y, Yang Q, Coombes C, McClellan M, Shridhar V, Emmings E, Shetty M, Chen L, Ai T, Meints J, Lee MK, Gardner M, Bazzaro M. UNC-45A Is a Novel Microtubule-Associated Protein and Regulator of Paclitaxel Sensitivity in Ovarian Cancer Cells. Mol Cancer Res 2019; 17:370-383. [PMID: 30322860 PMCID: PMC6359974 DOI: 10.1158/1541-7786.mcr-18-0670] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/11/2018] [Accepted: 10/02/2018] [Indexed: 12/14/2022]
Abstract
UNC-45A, a highly conserved member of the UCS (UNC45A/CRO1/SHE4P) protein family of cochaperones, plays an important role in regulating cytoskeletal-associated functions in invertebrates and mammalian cells, including cytokinesis, exocytosis, cell motility, and neuronal development. Here, for the first time, UNC-45A is demonstrated to function as a mitotic spindle-associated protein that destabilizes microtubules (MT) activity. Using in vitro biophysical reconstitution and total internal reflection fluorescence microscopy analysis, we reveal that UNC-45A directly binds to taxol-stabilized MTs in the absence of any additional cellular cofactors or other MT-associated proteins and acts as an ATP-independent MT destabilizer. In cells, UNC-45A binds to and destabilizes mitotic spindles, and its depletion causes severe defects in chromosome congression and segregation. UNC-45A is overexpressed in human clinical specimens from chemoresistant ovarian cancer and that UNC-45A-overexpressing cells resist chromosome missegregation and aneuploidy when treated with clinically relevant concentrations of paclitaxel. Lastly, UNC-45A depletion exacerbates paclitaxel-mediated stabilizing effects on mitotic spindles and restores sensitivity to paclitaxel. IMPLICATIONS: These findings reveal novel and significant roles for UNC-45A in regulation of cytoskeletal dynamics, broadening our understanding of the basic mechanisms regulating MT stability and human cancer susceptibility to paclitaxel, one of the most widely used chemotherapy agents for the treatment of human cancers.
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Affiliation(s)
- Ashley Mooneyham
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women’s Heath, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yoshie Iizuka
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women’s Heath, University of Minnesota, Minneapolis, MN 55455, USA
| | - Qing Yang
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Courtney Coombes
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Mark McClellan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Vijayalakshmi Shridhar
- Department of Experimental Pathology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Edith Emmings
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women’s Heath, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mihir Shetty
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women’s Heath, University of Minnesota, Minneapolis, MN 55455, USA
| | - Liqiang Chen
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455 USA
| | - Teng Ai
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455 USA
| | - Joyce Meints
- Department of Neuroscience, University of Minnesota Minneapolis, MN 55455 USA
| | - Michael K Lee
- Department of Neuroscience, University of Minnesota Minneapolis, MN 55455 USA
| | - Melissa Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Martina Bazzaro
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women’s Heath, University of Minnesota, Minneapolis, MN 55455, USA,,Corresponding author: Martina Bazzaro, Masonic Cancer Center, 420 Delaware Street S.E, Room 490, Minneapolis, Minnesota 55455, Tel: 612-6252889, Fax: 612-626-0665,
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24
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Dobrotkova V, Chlapek P, Mazanek P, Sterba J, Veselska R. Traffic lights for retinoids in oncology: molecular markers of retinoid resistance and sensitivity and their use in the management of cancer differentiation therapy. BMC Cancer 2018; 18:1059. [PMID: 30384831 PMCID: PMC6211450 DOI: 10.1186/s12885-018-4966-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 10/17/2018] [Indexed: 12/13/2022] Open
Abstract
For decades, retinoids and their synthetic derivatives have been well established anticancer treatments due to their ability to regulate cell growth and induce cell differentiation and apoptosis. Many studies have reported the promising role of retinoids in attaining better outcomes for adult or pediatric patients suffering from several types of cancer, especially acute myeloid leukemia and neuroblastoma. However, even this promising differentiation therapy has some limitations: retinoid toxicity and intrinsic or acquired resistance have been observed in many patients. Therefore, the identification of molecular markers that predict the therapeutic response to retinoid treatment is undoubtedly important for retinoid use in clinical practice. The purpose of this review is to summarize the current knowledge on candidate markers, including both genetic alterations and protein markers, for retinoid resistance and sensitivity in human malignancies.
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Affiliation(s)
- Viera Dobrotkova
- Laboratory of Tumor Biology, Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlarska 2, 61137 Brno, Czech Republic
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 65691 Brno, Czech Republic
| | - Petr Chlapek
- Laboratory of Tumor Biology, Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlarska 2, 61137 Brno, Czech Republic
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 65691 Brno, Czech Republic
| | - Pavel Mazanek
- Department of Pediatric Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Cernopolni 9, 61300 Brno, Czech Republic
| | - Jaroslav Sterba
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 65691 Brno, Czech Republic
- Department of Pediatric Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Cernopolni 9, 61300 Brno, Czech Republic
| | - Renata Veselska
- Laboratory of Tumor Biology, Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlarska 2, 61137 Brno, Czech Republic
- International Clinical Research Center, St. Anne’s University Hospital, Pekarska 53, 65691 Brno, Czech Republic
- Department of Pediatric Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, Cernopolni 9, 61300 Brno, Czech Republic
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25
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Escalante SG, Brightmore JA, Piper PW, Millson SH. UCS protein function is partially restored in the Saccharomyces cerevisiae she4 mutant with expression of the human UNC45-GC, but not UNC45-SM. Cell Stress Chaperones 2018; 23:609-615. [PMID: 29288355 PMCID: PMC6045556 DOI: 10.1007/s12192-017-0870-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/07/2017] [Accepted: 12/08/2017] [Indexed: 11/29/2022] Open
Abstract
A dedicated UNC45, Cro1, She4 (UCS) domain-containing protein assists in the Hsp90-mediated folding of the myosin head. Only weak sequence conservation exists between the single UCS protein of simple eukaryotes (She4 in budding yeast) and the two UCS proteins of higher organisms (the general cell and striated muscle UNC45s; UNC45-GC and UNC45-SM, respectively). In vertebrates, UNC45-GC facilitates cytoskeletal functions, whereas the 55% identical UNC45-SM assists assembly of the contractile apparatus of cardiac and skeletal muscles. A Saccharomyces cerevisiae she4Δ mutant, totally lacking any UCS protein, was engineered to express as its sole Hsp90 either the Hsp90α or the Hsp90β isoforms of human cytosolic Hsp90. A transient induction of the human UNC45-GC, but not UNC45-SM, could rescue the defective endocytosis in these she4Δ cells at 39 °C, irrespective of whether they possessed Hsp90α or Hsp90β. UNC45-GC-mediated rescue of the localisation of a Myo5-green fluorescent protein (GFP) fusion to cortical patches at 39 °C was more efficient in the yeast containing Hsp90α, though this may relate to more efficient functioning of Hsp90α as compared to Hsp90β in these strains. Furthermore, inducible expression of UNC45-GC, but not UNC45-SM, could partially rescue survival at a more extreme temperature (45 °C) that normally causes she4Δ mutant yeast cells to lyse. The results indicate that UCS protein function has been most conserved-yeast to man-in the UNC45-GC, not UNC45-SM. This may reflect UNC45-GC being the vertebrate UCS protein that assists formation of the actomyosin complexes needed for cytokinesis, cell morphological change, and organelle trafficking-events also facilitated by the myosins in yeast.
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Affiliation(s)
- Susana Gómez Escalante
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
- School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, LN6 7DL, UK
| | - Joseph A Brightmore
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
- School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, LN6 7DL, UK
| | - Peter W Piper
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK.
- School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, LN6 7DL, UK.
| | - Stefan H Millson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
- School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, LN6 7DL, UK
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26
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Wang L, Geist J, Grogan A, Hu LYR, Kontrogianni-Konstantopoulos A. Thick Filament Protein Network, Functions, and Disease Association. Compr Physiol 2018; 8:631-709. [PMID: 29687901 DOI: 10.1002/cphy.c170023] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sarcomeres consist of highly ordered arrays of thick myosin and thin actin filaments along with accessory proteins. Thick filaments occupy the center of sarcomeres where they partially overlap with thin filaments. The sliding of thick filaments past thin filaments is a highly regulated process that occurs in an ATP-dependent manner driving muscle contraction. In addition to myosin that makes up the backbone of the thick filament, four other proteins which are intimately bound to the thick filament, myosin binding protein-C, titin, myomesin, and obscurin play important structural and regulatory roles. Consistent with this, mutations in the respective genes have been associated with idiopathic and congenital forms of skeletal and cardiac myopathies. In this review, we aim to summarize our current knowledge on the molecular structure, subcellular localization, interacting partners, function, modulation via posttranslational modifications, and disease involvement of these five major proteins that comprise the thick filament of striated muscle cells. © 2018 American Physiological Society. Compr Physiol 8:631-709, 2018.
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Affiliation(s)
- Li Wang
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Janelle Geist
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Alyssa Grogan
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Li-Yen R Hu
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
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27
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Loss-of-Function Mutations in UNC45A Cause a Syndrome Associating Cholestasis, Diarrhea, Impaired Hearing, and Bone Fragility. Am J Hum Genet 2018; 102:364-374. [PMID: 29429573 DOI: 10.1016/j.ajhg.2018.01.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/11/2018] [Indexed: 12/13/2022] Open
Abstract
Despite the rapid discovery of genes for rare genetic disorders, we continue to encounter individuals presenting with syndromic manifestations. Here, we have studied four affected people in three families presenting with cholestasis, congenital diarrhea, impaired hearing, and bone fragility. Whole-exome sequencing of all affected individuals and their parents identified biallelic mutations in Unc-45 Myosin Chaperone A (UNC45A) as a likely driver for this disorder. Subsequent in vitro and in vivo functional studies of the candidate gene indicated a loss-of-function paradigm, wherein mutations attenuated or abolished protein activity with concomitant defects in gut development and function.
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28
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Hellerschmied D, Roessler M, Lehner A, Gazda L, Stejskal K, Imre R, Mechtler K, Dammermann A, Clausen T. UFD-2 is an adaptor-assisted E3 ligase targeting unfolded proteins. Nat Commun 2018; 9:484. [PMID: 29396393 PMCID: PMC5797217 DOI: 10.1038/s41467-018-02924-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 01/09/2018] [Indexed: 11/09/2022] Open
Abstract
Muscle development requires the coordinated activities of specific protein folding and degradation factors. UFD-2, a U-box ubiquitin ligase, has been reported to play a central role in this orchestra regulating the myosin chaperone UNC-45. Here, we apply an integrative in vitro and in vivo approach to delineate the substrate-targeting mechanism of UFD-2 and elucidate its distinct mechanistic features as an E3/E4 enzyme. Using Caenorhabditis elegans as model system, we demonstrate that UFD-2 is not regulating the protein levels of UNC-45 in muscle cells, but rather shows the characteristic properties of a bona fide E3 ligase involved in protein quality control. Our data demonstrate that UFD-2 preferentially targets unfolded protein segments. Moreover, the UNC-45 chaperone can serve as an adaptor protein of UFD-2 to poly-ubiquitinate unfolded myosin, pointing to a possible role of the UFD-2/UNC-45 pair in maintaining proteostasis in muscle cells.
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Affiliation(s)
- Doris Hellerschmied
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria.,Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, 06511, USA
| | - Max Roessler
- Max F. Perutz Laboratories (MFPL), University of Vienna, Doktor-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Anita Lehner
- Vienna Biocenter Core Facilities, Doktor-Bohr-Gasse 3, 1030, Vienna, Austria
| | - Linn Gazda
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Karel Stejskal
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Richard Imre
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Karl Mechtler
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Alexander Dammermann
- Max F. Perutz Laboratories (MFPL), University of Vienna, Doktor-Bohr-Gasse 9, 1030, Vienna, Austria.
| | - Tim Clausen
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria. .,Medical University of Vienna, Vienna BioCenter (VBC), 1030, Vienna, Austria.
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29
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Bujalowski PJ, Nicholls P, Garza E, Oberhauser AF. The central domain of UNC-45 chaperone inhibits the myosin power stroke. FEBS Open Bio 2018; 8:41-48. [PMID: 29321955 PMCID: PMC5757175 DOI: 10.1002/2211-5463.12346] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 10/27/2017] [Accepted: 10/31/2017] [Indexed: 11/07/2022] Open
Abstract
The multidomain UNC-45B chaperone is crucial for the proper folding and function of sarcomeric myosin. We recently found that UNC-45B inhibits the translocation of actin by myosin. The main functions of the UCS and TPR domains are known but the role of the central domain remains obscure. Here, we show-using in vitro myosin motility and ATPase assays-that the central domain alone acts as an inhibitor of the myosin power stroke through a mechanism that allows ATP turnover. Hence, UNC-45B is a unique chaperone in which the TPR domain recruits Hsp90; the UCS domain possesses chaperone-like activities; and the central domain interacts with myosin and inhibits the actin translocation function of myosin. We hypothesize that the inhibitory function plays a critical role during the assembly of myofibrils under stress and during the sarcomere development process.
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Affiliation(s)
- Paul J Bujalowski
- Department of Biochemistry and Molecular Biology The University of Texas Medical Branch Galveston TX USA
| | - Paul Nicholls
- Baylor College of Medicine The University of Texas Medical Branch Galveston TX USA
| | - Eleno Garza
- Department of Neuroscience and Cell Biology The University of Texas Medical Branch Galveston TX USA
| | - Andres F Oberhauser
- Department of Biochemistry and Molecular Biology The University of Texas Medical Branch Galveston TX USA.,Department of Neuroscience and Cell Biology The University of Texas Medical Branch Galveston TX USA.,Sealy Center for Structural Biology and Molecular Biophysics The University of Texas Medical Branch Galveston TX USA
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30
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Lehtimäki JI, Fenix AM, Kotila TM, Balistreri G, Paavolainen L, Varjosalo M, Burnette DT, Lappalainen P. UNC-45a promotes myosin folding and stress fiber assembly. J Cell Biol 2017; 216:4053-4072. [PMID: 29055011 PMCID: PMC5716280 DOI: 10.1083/jcb.201703107] [Citation(s) in RCA: 28] [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: 03/15/2017] [Revised: 08/28/2017] [Accepted: 09/19/2017] [Indexed: 12/15/2022] Open
Abstract
Contractile actomyosin bundles, stress fibers, are crucial for adhesion, morphogenesis, and mechanosensing in nonmuscle cells. However, the mechanisms by which nonmuscle myosin II (NM-II) is recruited to those structures and assembled into functional bipolar filaments have remained elusive. We report that UNC-45a is a dynamic component of actin stress fibers and functions as a myosin chaperone in vivo. UNC-45a knockout cells display severe defects in stress fiber assembly and consequent abnormalities in cell morphogenesis, polarity, and migration. Experiments combining structured-illumination microscopy, gradient centrifugation, and proteasome inhibition approaches revealed that a large fraction of NM-II and myosin-1c molecules fail to fold in the absence of UNC-45a. The remaining properly folded NM-II molecules display defects in forming functional bipolar filaments. The C-terminal UNC-45/Cro1/She4p domain of UNC-45a is critical for NM-II folding, whereas the N-terminal tetratricopeptide repeat domain contributes to the assembly of functional stress fibers. Thus, UNC-45a promotes generation of contractile actomyosin bundles through synchronized NM-II folding and filament-assembly activities.
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Affiliation(s)
| | - Aidan M Fenix
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Tommi M Kotila
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Giuseppe Balistreri
- Department of Biosciences, Division of General Microbiology, University of Helsinki, Helsinki, Finland
| | - Lassi Paavolainen
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
| | - Markku Varjosalo
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Dylan T Burnette
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN
| | - Pekka Lappalainen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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31
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Frénal K, Jacot D, Hammoudi PM, Graindorge A, Maco B, Soldati-Favre D. Myosin-dependent cell-cell communication controls synchronicity of division in acute and chronic stages of Toxoplasma gondii. Nat Commun 2017; 8:15710. [PMID: 28593938 PMCID: PMC5477499 DOI: 10.1038/ncomms15710] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 04/17/2017] [Indexed: 01/20/2023] Open
Abstract
The obligate intracellular parasite Toxoplasma gondii possesses a repertoire of 11 myosins. Three class XIV motors participate in motility, invasion and egress, whereas the class XXII myosin F is implicated in organelle positioning and inheritance of the apicoplast. Here we provide evidence that TgUNC acts as a chaperone dedicated to the folding, assembly and function of all Toxoplasma myosins. The conditional ablation of TgUNC recapitulates the phenome of the known myosins and uncovers two functions in parasite basal complex constriction and synchronized division within the parasitophorous vacuole. We identify myosin J and centrin 2 as essential for the constriction. We demonstrate the existence of an intravacuolar cell–cell communication ensuring synchronized division, a process dependent on myosin I. This connectivity contributes to the delayed death phenotype resulting from loss of the apicoplast. Cell–cell communication is lost in activated macrophages and during bradyzoite differentiation resulting in asynchronized, slow division in the cysts. The mechanism by which Toxoplasma gondii achieves synchronized cell division is incompletely understood. Here, the authors identify an intravacuolar cell-cell communication that ensures synchronized division and depends on myosin I.
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Affiliation(s)
- Karine Frénal
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
| | - Damien Jacot
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
| | - Pierre-Mehdi Hammoudi
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
| | - Arnault Graindorge
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
| | - Bohumil Maco
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 Rue Michel-Servet, 1206 Geneva, Switzerland
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32
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Sala AJ, Bott LC, Morimoto RI. Shaping proteostasis at the cellular, tissue, and organismal level. J Cell Biol 2017; 216:1231-1241. [PMID: 28400444 PMCID: PMC5412572 DOI: 10.1083/jcb.201612111] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/20/2017] [Accepted: 03/20/2017] [Indexed: 01/22/2023] Open
Abstract
The proteostasis network (PN) regulates protein synthesis, folding, transport, and degradation to maintain proteome integrity and limit the accumulation of protein aggregates, a hallmark of aging and degenerative diseases. In multicellular organisms, the PN is regulated at the cellular, tissue, and systemic level to ensure organismal health and longevity. Here we review these three layers of PN regulation and examine how they collectively maintain cellular homeostasis, achieve cell type-specific proteomes, and coordinate proteostasis across tissues. A precise understanding of these layers of control has important implications for organismal health and could offer new therapeutic approaches for neurodegenerative diseases and other chronic disorders related to PN dysfunction.
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Affiliation(s)
- Ambre J Sala
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
| | - Laura C Bott
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
| | - Richard I Morimoto
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
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33
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Iizuka Y, Mooneyham A, Sieben A, Chen K, Maile M, Hellweg R, Schütz F, Teckle K, Starr T, Thayanithy V, Vogel RI, Lou E, Lee MK, Bazzaro M. UNC-45A is required for neurite extension via controlling NMII activation. Mol Biol Cell 2017; 28:1337-1346. [PMID: 28356421 PMCID: PMC5426848 DOI: 10.1091/mbc.e16-06-0381] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 03/15/2017] [Accepted: 03/21/2017] [Indexed: 01/13/2023] Open
Abstract
UNC-45A is a novel regulator of neuronal differentiation. UNC-45A localizes at the growth cone, binds to NMIIA and NMIIB, and is disposable for neuronal survival but is required for neurite initiation and extension via regulating NMII activation. Thus UNC-45A is a potential master regulator of a number of NMII-mediated cellular processes. UNC-45A is a highly conserved member of the UNC-45/CRO1/She4p family of proteins, which act as chaperones for conventional and nonconventional myosins. NMII mediates contractility and actin-based motility, which are fundamental for proper growth cone motility and neurite extension. The presence and role of UNC-45A in neuronal differentiation have been largely unknown. Here we demonstrate that UNC-45A is a novel growth cone–localized, NMII-associated component of the multiprotein complex regulating growth cone dynamics. We show that UNC-45A is dispensable for neuron survival but required for neurite elongation. Mechanistically, loss of UNC-45A results in increased levels of NMII activation. Collectively our results provide novel insights into the molecular mechanisms of neurite growth and define UNC-45A as a novel and master regulator of NMII-mediated cellular processes in neurons.
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Affiliation(s)
- Yoshie Iizuka
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Ashley Mooneyham
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Andrew Sieben
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Kevin Chen
- Department of Biology, University of Maryland, Baltimore, MD 21250
| | - Makayla Maile
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Raffaele Hellweg
- Breast Unit, University of Heidelberg, 69120 Heidelberg, Germany
| | - Florian Schütz
- Breast Unit, University of Heidelberg, 69120 Heidelberg, Germany
| | - Kebebush Teckle
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Timothy Starr
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Venugopal Thayanithy
- Division of Hematology, Oncology and Transplantation, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Rachel Isaksson Vogel
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Emil Lou
- Division of Hematology, Oncology and Transplantation, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Michael K Lee
- Department of Neuroscience, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Martina Bazzaro
- Masonic Cancer Center and Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
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34
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Gomez-Escalante S, Piper PW, Millson SH. Mutation of the Ser18 phosphorylation site on the sole Saccharomyces cerevisiae UCS protein, She4, can compromise high-temperature survival. Cell Stress Chaperones 2017; 22:135-141. [PMID: 27888470 PMCID: PMC5225067 DOI: 10.1007/s12192-016-0750-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 10/11/2016] [Accepted: 11/15/2016] [Indexed: 01/27/2023] Open
Abstract
Folding of the myosin head often requires the joint actions of Hsp90 and a dedicated UNC45, Cro1, She4 (UCS) domain-containing cochaperone protein. Relatively weak sequence conservation exists between the single UCS protein of simple eukaryotes (She4 in budding yeast) and the two UCS proteins of higher organisms (the general cell and smooth muscle UNC45s; UNC45-GC and UNC45-SM respectively). In vertebrates, UNC45-GC facilitates cytoskeletal function whereas the 55% identical UNC45-SM assists in the assembly of the contractile apparatus of cardiac and skeletal muscles. UNC45-SM, unlike UNC45-GC, shares with yeast She4 an IDSL sequence motif known to be a site of in vivo serine phosphorylation in yeast. Investigating this further, we found that both a non-phosphorylatable (S18A) and a phosphomimetic (S18E) mutant form of She4 could rescue the type 1 myosin localisation and endocytosis defects of the yeast she4Δ mutant at 39 °C. Nevertheless, at higher temperature (45 °C), only She4 (S18A), not She4(S18E), could substantially rescue the cell lysis defect of she4Δ mutant cells. In the yeast two-hybrid system, the non-phosphorylatable S18A and S251A mutant forms of She4 and UNC45-SM still displayed the stress-enhanced in vivo interaction with Hsp90 seen with the wild-type She4 and UNC45-SM. Such high-temperature enforcement to interaction was though lost with the phosphomimetic mutant forms (She4(S18E) and UNC45-SM (S251E)), an indication that phosphorylation might suppress these increases in She4/Hsp90 and UNC45-SM/Hsp90 interaction with stress.
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Affiliation(s)
- Susana Gomez-Escalante
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN,, UK
| | - Peter W Piper
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN,, UK.
| | - Stefan H Millson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN,, UK
- School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, LN6 7DL,, UK
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35
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Hu J, Guo T, Pan WQ, Gan T, Wei J, Wang JP, Leng XJ, Li XQ. Cloning, molecular characterization, and expression analysis of the unc45 myosin chaperone b(unc45b)gene of grass carp (Ctenopharyngodon idellus). J Muscle Res Cell Motil 2016; 37:71-81. [PMID: 27334505 DOI: 10.1007/s10974-016-9445-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 06/02/2016] [Indexed: 11/30/2022]
Abstract
Unc45 myosin chaperone b(unc45b)gene is a molecular chaperone that mediates the folding, assembly and accumulation of thick-filament myosin in the formation of sarcomere, which plays an important role in the development of striated muscle and the stability of sarcomere. In this study, the complete cDNA sequence of unc45b gene of grass carp was obtained by rapid amplification of cDNA ends (RACE), and the characteristics of the unc45b protein predicted from gene sequence was analyzed by bioinformatics methods. The differential expression pattern in tissues was also detected by quantitative real-time PCR. The results showed that the full-length of unc45b gene of grass carp is 3163 bp, which contains a 60 bp 5'UTR, a 298 bp 3'UTR, and a 2865 bp open reading frame (ORF) encoding a 934 amino acid peptide. The deduced unc45b protein exhibits a homology of 92, 86, 86 % with the protein of zebrafish (Danio rerio), channel catfish (Ietalurus punctatus) and tilapia (Oreochromis niloticus) respectively, and the protein contains UCS myosin head binding domain and TPR peptide repeat domain. The protein is a hydrophilic and non-secretory protein with a molecular mass and isoeletronic point of 103,699.8 and 7.39 Da. The structural elements of the protein includes α-helixes and loops, and the unc45b gene highly expresses in skeletal muscle and heart in grass carp. This study laid a foundation for further research in explaining the myofibril accumulation in crisped grass carp.
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Affiliation(s)
- Jing Hu
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Ting Guo
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Wen-Qian Pan
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Tian Gan
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Jing Wei
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Jun-Peng Wang
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China
| | - Xiang-Jun Leng
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China.
| | - Xiao-Qin Li
- The College of Fisheries and Life Science, Shanghai Ocean University, No. 999, Huchenghuan Road, Shanghai, 201306, China.
- Key Laboratory of Freshwater Fishery Germplasm Resources, Ministry of Agriculture, No. 999, Huchenghuan Road, Shanghai, 201306, China.
- Shanghai Engineering Research Center of Aquaculture, No. 999, Huchenghuan Road, Shanghai, 201306, China.
- Shanghai University Knowledge Service Platform, Shanghai Ocean University Aquatic Animal Breeding Center, No. 999, Huchenghuan Road, Shanghai, 201306, China.
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Etard C, Armant O, Roostalu U, Gourain V, Ferg M, Strähle U. Loss of function of myosin chaperones triggers Hsf1-mediated transcriptional response in skeletal muscle cells. Genome Biol 2015; 16:267. [PMID: 26631063 PMCID: PMC4668643 DOI: 10.1186/s13059-015-0825-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 11/05/2015] [Indexed: 01/03/2023] Open
Abstract
Background Mutations in myosin chaperones Unc45b and Hsp90aa1.1 as well as in the Unc45b-binding protein Smyd1b impair formation of myofibrils in skeletal muscle and lead to the accumulation of misfolded myosin. The concomitant transcriptional response involves up-regulation of the three genes encoding these proteins, as well as genes involved in muscle development. The transcriptional up-regulation of unc45b, hsp90aa1.1 and smyd1b is specific to zebrafish mutants with myosin folding defects, and is not triggered in other zebrafish myopathy models. Results By dissecting the promoter of unc45b, we identify a Heat shock factor 1 (Hsf1) binding element as a mediator of unc45b up-regulation in myofibers lacking myosin folding proteins. Loss-of-function of Hsf1 abolishes unc45b up-regulation in mutants with defects in myosin folding. Conclusions Taken together, our data show that skeletal muscle cells respond to defective myosin chaperones with a complex gene program and suggest that this response is mediated by Hsf1 activation. Electronic supplementary material The online version of this article (doi:10.1186/s13059-015-0825-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christelle Etard
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus Nord, PO box, Karlsruhe, Germany
| | - Olivier Armant
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus Nord, PO box, Karlsruhe, Germany
| | - Urmas Roostalu
- Present address: Institute of Inflammation and Repair, Michael Smith Bldg, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Victor Gourain
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus Nord, PO box, Karlsruhe, Germany
| | - Marco Ferg
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus Nord, PO box, Karlsruhe, Germany
| | - Uwe Strähle
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus Nord, PO box, Karlsruhe, Germany.
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Iizuka Y, Cichocki F, Sieben A, Sforza F, Karim R, Coughlin K, Isaksson Vogel R, Gavioli R, McCullar V, Lenvik T, Lee M, Miller J, Bazzaro M. UNC-45A Is a Nonmuscle Myosin IIA Chaperone Required for NK Cell Cytotoxicity via Control of Lytic Granule Secretion. THE JOURNAL OF IMMUNOLOGY 2015; 195:4760-70. [PMID: 26438524 DOI: 10.4049/jimmunol.1500979] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 09/06/2015] [Indexed: 11/19/2022]
Abstract
NK cell's killing is a tightly regulated process under the control of specific cytoskeletal proteins. This includes Wiskott-Aldrich syndrome protein, Wiskott-Aldrich syndrome protein-interacting protein, cofilin, Munc13-4, and nonmuscle myosin IIA (NMIIA). These proteins play a key role in controlling NK-mediated cytotoxicity either via regulating the attachment of lytic granules to the actin-based cytoskeleton or via promoting the cytoskeletal reorganization that is requisite for lytic granule release. UNC-45A is a highly conserved member of the UNC-45/CRO1/She4p family of proteins that act as chaperones for both conventional and nonconventional myosin. Although we and others have shown that in lower organisms and in mammalian cells NMIIA-associated functions, such as cytokinesis, cell motility, and organelle trafficking, are dependent upon the presence of UNC-45A, its role in NK-mediated functions is largely unknown. In this article, we describe UNC-45A as a key regulator of NK-mediated cell toxicity. Specifically we show that, in human NK cells, UNC-45A localize at the NK cell immunological synapse of activated NK cells and is part of the multiprotein complex formed during NK cell activation. Furthermore, we show that UNC-45A is disposable for NK cell immunological synapse formation and lytic granules reorientation but crucial for lytic granule exocytosis. Lastly, loss of UNC-45A leads to reduced NMIIA binding to actin, suggesting that UNC-45A is a crucial component in regulating human NK cell cytoskeletal dynamics via promoting the formation of actomyosin complexes.
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Affiliation(s)
- Yoshie Iizuka
- Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Frank Cichocki
- Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, MN 55455
| | - Andrew Sieben
- Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Fabio Sforza
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy; and
| | - Razaul Karim
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455
| | - Kathleen Coughlin
- Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Rachel Isaksson Vogel
- Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455
| | - Riccardo Gavioli
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy; and
| | - Valarie McCullar
- Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, MN 55455
| | - Todd Lenvik
- Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, MN 55455
| | - Michael Lee
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455
| | - Jeffrey Miller
- Hematology, Oncology and Transplantation, University of Minnesota, Minneapolis, MN 55455
| | - Martina Bazzaro
- Department of Obstetrics, Gynecology and Women's Heath, University of Minnesota Twin Cities, Minneapolis, MN 55455;
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Bujalowski PJ, Nicholls P, Oberhauser AF. UNC-45B chaperone: the role of its domains in the interaction with the myosin motor domain. Biophys J 2015; 107:654-661. [PMID: 25099804 DOI: 10.1016/j.bpj.2014.05.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/22/2014] [Accepted: 05/29/2014] [Indexed: 11/15/2022] Open
Abstract
The proper folding of many proteins can only be achieved by interaction with molecular chaperones. The molecular chaperone UNC-45B is required for the folding of striated muscle myosin II. However, the precise mechanism by which it contributes to proper folding of the myosin head remains unclear. UNC-45B contains three domains: an N-terminal TPR domain known to bind Hsp90, a Central domain of unknown function, and a C-terminal UCS domain known to interact with the myosin head. Here we used fluorescence titrations methods, dynamic light scattering, and single-molecule atomic force microscopy (AFM) unfolding/refolding techniques to study the interactions of the UCS and Central domains with the myosin motor domain. We found that both the UCS and the Central domains bind to the myosin motor domain. Our data show that the domains bind to distinct subsites on the myosin head, suggesting distinct roles in forming the myosin-UNC-45B complex. To determine the chaperone activity of the UCS and Central domains, we used two different methods: 1), prevention of misfolding using single-molecule AFM, and 2), prevention of aggregation using dynamic light scattering. Using the first method, we found that the UCS domain is sufficient to prevent misfolding of a titin mechanical reporter. Application of the second method showed that the UCS domain but not the Central domain prevents the thermal aggregation of the myosin motor domain. We conclude that while both the UCS and the Central domains bind the myosin head with high affinity, only the UCS domain displays chaperone activity.
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Affiliation(s)
- Paul J Bujalowski
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Paul Nicholls
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Department of Biochemistry Molecular Biology, University of Texas Medical Branch, Galveston, Texas
| | - Andres F Oberhauser
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas; Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, Texas.
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39
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Abstract
The UCS (UNC-45/CRO1/She4p) family of proteins has emerged as chaperones that are specific for the folding, assembly and function of myosin. These proteins participate in various important myosin-dependent cellular processes that include myofibril organization and muscle functions, cell differentiation, cardiac and skeletal muscle development, cytokinesis and endocytosis. Mutations in the genes that code for UCS proteins cause serious defects in these actomyosin-based processes. Homologs of UCS proteins can be broadly divided into (1) animal UCS proteins, generally known as UNC-45 proteins, which contain an N-terminal tetratricopeptide repeat (TPR) domain in addition to the canonical UCS domain, and (2) fungal UCS proteins, which lack the TPR domain. Structurally, except for TPR domain, both sub-classes of UCS proteins comprise of several irregular armadillo (ARM) repeats that are divided into two-domain architecture: a combined central-neck domain and a C-terminal UCS domain. Structural analyses suggest that UNC-45 proteins form elongated oligomers that serve as scaffolds to recruit Hsp90 and/or Hsp70 to form a multi-protein chaperoning complex that assists myosin heads to fold and simultaneously organize them into myofibrils. Similarly, fungal UCS proteins may dimerize to promote folding of non-muscle myosins as well as determine their step size along actin filaments. These findings confirm UCS proteins as a new class of myosin-specific chaperones and co-chaperones for Hsp90. This chapter reviews the implications of the outcome of studies on these proteins in cellular processes such as muscle formation, and disease states such as myopathies and cancer.
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Affiliation(s)
- Weiming Ni
- Department of Genetics, Howard Hughes Medical Institute, Yale School of Medicine, 06520, New Haven, CT, USA,
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40
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Thermally-induced structural changes in an armadillo repeat protein suggest a novel thermosensor mechanism in a molecular chaperone. FEBS Lett 2014; 589:123-30. [PMID: 25436418 DOI: 10.1016/j.febslet.2014.11.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 11/18/2014] [Accepted: 11/19/2014] [Indexed: 01/12/2023]
Abstract
Molecular chaperones are commonly identified by their ability to suppress heat-induced protein aggregation. The muscle-specific molecular chaperone UNC-45B is known to be involved in myosin folding and is trafficked to the sarcomeres A-band during thermal stress. Here, we identify temperature-dependent structural changes in the UCS chaperone domain of UNC-45B that occur within a physiologically relevant heat-shock range. We show that distinct changes to the armadillo repeat protein topology result in exposure of hydrophobic patches, and increased flexibility of the molecule. These rearrangements suggest the existence of a novel thermosensor within the chaperone domain of UNC-45B. We propose that these changes may function to suppress aggregation under stress by allowing binding to a wide variety of aggregation prone loops on its client.
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41
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Jilani Y, Lu S, Lei H, Karnitz LM, Chadli A. UNC45A localizes to centrosomes and regulates cancer cell proliferation through ChK1 activation. Cancer Lett 2014; 357:114-120. [PMID: 25444911 DOI: 10.1016/j.canlet.2014.11.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 11/05/2014] [Accepted: 11/06/2014] [Indexed: 11/26/2022]
Abstract
The UCS family of proteins regulates cellular functions through their interactions with myosin. Here we show that one member of this family, UNC45A, is also a novel centrosomal protein. UNC45A is required for cellular proliferation of cancer cell in vitro and for tumor growth in vivo through its ability to bind and regulate ChK1 nuclear-cytoplasmic localization in an Hsp90-independent manner. Immunocytochemical and biochemical fractionation studies revealed that UNC45A and ChK1 co-localize to the centrosome. Inhibition of UNC45A expression reduced ChK1 activation and its tethering to the centrosome, events required for proper centrosome function. Lack of UNC45A caused the accumulation of multi-nucleated cells, consistent with a defect in Chk1 regulation of centrosomes. These findings identify a novel centrosomal function for UNC45A and its role in cell proliferation and tumorigenesis.
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Affiliation(s)
- Yasmeen Jilani
- Molecular Oncology and Biomarkers Program, GRU Cancer Center, Georgia Regents University, 1410 Laney Walker Blvd, CN-3151, Augusta, GA 30912, USA
| | - Su Lu
- Molecular Oncology and Biomarkers Program, GRU Cancer Center, Georgia Regents University, 1410 Laney Walker Blvd, CN-3151, Augusta, GA 30912, USA
| | - Huang Lei
- Cancer Immunology, Inflammation, and Tolerance Program, Georgia Regents University Cancer Center, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912
| | - Larry M Karnitz
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Ahmed Chadli
- Molecular Oncology and Biomarkers Program, GRU Cancer Center, Georgia Regents University, 1410 Laney Walker Blvd, CN-3151, Augusta, GA 30912, USA.
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42
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Nicholls P, Bujalowski PJ, Epstein HF, Boehning DF, Barral JM, Oberhauser AF. Chaperone-mediated reversible inhibition of the sarcomeric myosin power stroke. FEBS Lett 2014; 588:3977-81. [DOI: 10.1016/j.febslet.2014.09.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 08/13/2014] [Accepted: 09/03/2014] [Indexed: 11/30/2022]
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43
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Smith DA, Carland CR, Guo Y, Bernstein SI. Getting Folded: Chaperone Proteins in Muscle Development, Maintenance and Disease. Anat Rec (Hoboken) 2014; 297:1637-49. [DOI: 10.1002/ar.22980] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/11/2014] [Accepted: 04/12/2014] [Indexed: 01/07/2023]
Affiliation(s)
- Daniel A. Smith
- Department of Biology, The Molecular Biology Institute; San Diego State University; San Diego California
| | - Carmen R. Carland
- Department of Biology, The Molecular Biology Institute; San Diego State University; San Diego California
| | - Yiming Guo
- Department of Biology, The Molecular Biology Institute; San Diego State University; San Diego California
| | - Sanford I. Bernstein
- Department of Biology, The Molecular Biology Institute; San Diego State University; San Diego California
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44
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Abstract
Nematodes are amongst the most successful and abundant organisms on the planet with approximately 30 000 species described, although the actual number of species is estimated to be one million or more. Despite sharing a relatively simple and invariant body plan, there is considerable diversity within the phylum. Nematodes have evolved to colonize most ecological niches, and can be free-living or can parasitize plants or animals to the detriment of the host organism. In this review we consider the role of heat shock protein 90 (Hsp90) in the nematode life cycle. We describe studies on Hsp90 in the free-living nematode Caenorhabditis elegans and comparative work on the parasitic species Brugia pahangi, and consider whether a dependence upon Hsp90 can be exploited for the control of parasitic species.
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45
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The myosin chaperone UNC45B is involved in lens development and autosomal dominant juvenile cataract. Eur J Hum Genet 2014; 22:1290-7. [PMID: 24549050 DOI: 10.1038/ejhg.2014.21] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 01/17/2014] [Accepted: 01/22/2014] [Indexed: 01/17/2023] Open
Abstract
Genome-wide linkage analysis, followed by targeted deep sequencing, in a Danish multigeneration family with juvenile cataract revealed a region of chromosome 17 co-segregating with the disease trait. Affected individuals were heterozygous for two potentially protein-disrupting alleles in this region, in ACACA and UNC45B. As alterations of the UNC45B protein have been shown to affect eye development in model organisms, effort was focused on the heterozygous UNC45B missense mutation. UNC45B encodes a myosin-specific chaperone that, together with the general heat shock protein HSP90, is involved in myosin assembly. The mutation changes p.Arg805 to Trp in the UCS domain, an amino acid that is highly conserved from yeast to human. UNC45B is strongly expressed in the heart and skeletal muscle tissue, but here we show expression in human embryo eye and zebrafish lens. The zebrafish mutant steif, carrying an unc45b nonsense mutation, has smaller eyes than wild-type embryos and shows accumulation of nuclei in the lens. Injection of RNA encoding the human wild-type UNC45B protein into the steif homozygous embryo reduced the nuclei accumulation and injection of human mutant UNC45B cDNA in wild-type embryos resulted in development of a phenotype similar to the steif mutant. The p.Arg805Trp alteration in the mammalian UNC45B gene suggests that developmental cataract may be caused by a defect in non-muscle myosin assembly during maturation of the lens fiber cells.
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46
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Lee CF, Melkani GC, Bernstein SI. The UNC-45 myosin chaperone: from worms to flies to vertebrates. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 313:103-44. [PMID: 25376491 DOI: 10.1016/b978-0-12-800177-6.00004-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
UNC-45 (uncoordinated mutant number 45) is a UCS (UNC-45, CRO1, She4p) domain protein that is critical for myosin stability and function. It likely aides in folding myosin during cellular differentiation and maintenance, and protects myosin from denaturation during stress. Invertebrates have a single unc-45 gene that is expressed in both muscle and nonmuscle tissues. Vertebrates possess one gene expressed in striated muscle (unc-45b) and another that is more generally expressed (unc-45a). Structurally, UNC-45 is composed of a series of α-helices connected by loops. It has an N-terminal tetratricopeptide repeat domain that binds to Hsp90 and a central domain composed of armadillo repeats. Its C-terminal UCS domain, which is also comprised of helical armadillo repeats, interacts with myosin. In this chapter, we present biochemical, structural, and genetic analyses of UNC-45 in Caenorhabditis elegans, Drosophila melanogaster, and various vertebrates. Further, we provide insights into UNC-45 functions, its potential mechanism of action, and its roles in human disease.
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Affiliation(s)
- Chi F Lee
- Department of Biology, San Diego State University, San Diego, CA, USA
| | - Girish C Melkani
- Department of Biology, San Diego State University, San Diego, CA, USA
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Hellerschmied D, Clausen T. Myosin chaperones. Curr Opin Struct Biol 2013; 25:9-15. [PMID: 24440450 PMCID: PMC4045384 DOI: 10.1016/j.sbi.2013.11.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/08/2013] [Accepted: 11/08/2013] [Indexed: 12/31/2022]
Abstract
The folding and assembly of myosin motor proteins is essential for most movement processes at the cellular, but also at the organism level. Importantly, myosins, which represent a very diverse family of proteins, require the activity of general and specialized folding factors to develop their full motor function. The activities of the myosin-specific UCS (UNC-45/Cro1/She4) chaperones range from assisting acto-myosin dependent transport processes to scaffolding multi-subunit chaperone complexes, which are required to assemble myofilaments. Recent structure-function studies revealed the structural organization of TPR (tetratricopeptide repeat)-containing and TPR-less UCS chaperones. The observed structural differences seem to reflect the specialized and remarkably versatile working mechanisms of myosin-directed chaperones, as will be discussed in this review.
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Affiliation(s)
- Doris Hellerschmied
- Research Institute of Molecular Pathology, Dr. Bohrgasse 7, A-1030 Vienna, Austria
| | - Tim Clausen
- Research Institute of Molecular Pathology, Dr. Bohrgasse 7, A-1030 Vienna, Austria.
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Stark BC, James ML, Pollard LW, Sirotkin V, Lord M. UCS protein Rng3p is essential for myosin-II motor activity during cytokinesis in fission yeast. PLoS One 2013; 8:e79593. [PMID: 24244528 PMCID: PMC3828377 DOI: 10.1371/journal.pone.0079593] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 09/27/2013] [Indexed: 12/25/2022] Open
Abstract
UCS proteins have been proposed to operate as co-chaperones that work with Hsp90 in the de novo folding of myosin motors. The fission yeast UCS protein Rng3p is essential for actomyosin ring assembly and cytokinesis. Here we investigated the role of Rng3p in fission yeast myosin-II (Myo2p) motor activity. Myo2p isolated from an arrested rng3-65 mutant was capable of binding actin, yet lacked stability and activity based on its expression levels and inactivity in ATPase and actin filament gliding assays. Myo2p isolated from a myo2-E1 mutant (a mutant hyper-sensitive to perturbation of Rng3p function) showed similar behavior in the same assays and exhibited an altered motor conformation based on limited proteolysis experiments. We propose that Rng3p is not required for the folding of motors per se, but instead works to ensure the activity of intrinsically unstable myosin-II motors. Rng3p is specific to conventional myosin-II and the actomyosin ring, and is not required for unconventional myosin motor function at other actin structures. However, artificial destabilization of myosin-I motors at endocytic actin patches (using a myo1-E1 mutant) led to recruitment of Rng3p to patches. Thus, while Rng3p is specific to myosin-II, UCS proteins are adaptable and can respond to changes in the stability of other myosin motors.
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Affiliation(s)
- Benjamin C. Stark
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont, United States of America
| | - Michael L. James
- Department of Cell and Developmental Biology, State University of New York - Upstate Medical University, Syracuse, New York, United States of America
| | - Luther W. Pollard
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont, United States of America
| | - Vladimir Sirotkin
- Department of Cell and Developmental Biology, State University of New York - Upstate Medical University, Syracuse, New York, United States of America
| | - Matthew Lord
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont, United States of America
- * E-mail:
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Li H, Zhong Y, Wang Z, Gao J, Xu J, Chu W, Zhang J, Fang S, Du SJ. Smyd1b is required for skeletal and cardiac muscle function in zebrafish. Mol Biol Cell 2013; 24:3511-21. [PMID: 24068325 PMCID: PMC3826989 DOI: 10.1091/mbc.e13-06-0352] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Myofibrillogenesis is critical for muscle cell differentiation and contraction. This study shows that Smyd1b plays a key role in myofibrillogenesis in muscle cells. Knockdown of smyd1b results in up-regulation of hsp90α1 and unc45b gene expression, increased myosin degradation, and disruption of sarcomere organization in zebrafish embryos. Smyd1b is a member of the Smyd family that is specifically expressed in skeletal and cardiac muscles. Smyd1b plays a key role in thick filament assembly during myofibrillogenesis in skeletal muscles of zebrafish embryos. To better characterize Smyd1b function and its mechanism of action in myofibrillogenesis, we analyzed the effects of smyd1b knockdown on myofibrillogenesis in skeletal and cardiac muscles of zebrafish embryos. The results show that knockdown of smyd1b causes significant disruption of myofibril organization in both skeletal and cardiac muscles of zebrafish embryos. Microarray and quantitative reverse transcription-PCR analyses show that knockdown of smyd1b up-regulates heat shock protein 90 (hsp90) and unc45b gene expression. Biochemical analysis reveals that Smyd1b can be coimmunoprecipitated with heat shock protein 90 α-1 and Unc45b, two myosin chaperones expressed in muscle cells. Consistent with its potential function in myosin folding and assembly, knockdown of smyd1b significantly reduces myosin protein accumulation without affecting mRNA expression. This likely results from increased myosin degradation involving unc45b overexpression. Together these data support the idea that Smyd1b may work together with myosin chaperones to control myosin folding, degradation, and assembly into sarcomeres during myofibrillogenesis.
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Affiliation(s)
- Huiqing Li
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21202 Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201 Laboratory of Pathology, National Cancer Institute, Bethesda, MD 20892 Department of Bioengineering and Environmental Science, Changsha University, Hunan 410003, China
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Pokrzywa W, Hoppe T. Chaperoning myosin assembly in muscle formation and aging. WORM 2013; 2:e25644. [PMID: 24778937 PMCID: PMC3875649 DOI: 10.4161/worm.25644] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 07/05/2013] [Indexed: 01/06/2023]
Abstract
The activity and assembly of various myosin subtypes is coordinated by conserved UCS (UNC-45/CRO1/She4p) domain proteins. One founding member of the UCS family is the Caenorhabditis elegans UNC-45 protein important for the organization of striated muscle filaments. Our recent structural and biochemical results demonstrated that UNC-45 forms a protein chain with defined periodicity of myosin interaction domains. Intriguingly, the UNC-45 chain serves as docking platform for myosin molecules, which promotes ordered spacing and incorporation of myosin into contractile muscle sarcomeres. The physiological relevance of this observation was demonstrated in C. elegans by transgenic expression of UNC-45 chain formation mutants, which provokes defects in muscle structure and size. Collaborating with the molecular chaperones, Hsp70 and Hsp90, chain formation of UNC-45 links myosin folding with myofilament assembly. Here, we discuss our recent findings on the dynamic regulation of UNC-45 structure and stability in the context of muscle regeneration mechanisms that are affected in myopathic diseases and during aging.
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Affiliation(s)
- Wojciech Pokrzywa
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD); University of Cologne; Cologne, Germany
| | - Thorsten Hoppe
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD); University of Cologne; Cologne, Germany
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