1
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Streeter O, Shi K, Vavra J, Aihara H, Ervasti JM, Evans R, Muretta JM. Human dystrophin tandem calponin homology actin-binding domain crystallized in a closed-state conformation. Acta Crystallogr D Struct Biol 2025; 81:122-129. [PMID: 40007458 PMCID: PMC11883666 DOI: 10.1107/s2059798325001457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2024] [Accepted: 02/17/2025] [Indexed: 02/27/2025] Open
Abstract
The structure of the N-terminal actin-binding domain of human dystrophin was determined at 1.94 Å resolution. Each chain in the asymmetric unit exists in a `closed' conformation, with the first and second calponin homology (CH) domains directly interacting via a 2500.6 Å2 interface. The positioning of the individual CH domains is comparable to the domain-swapped dimer seen in previous human dystrophin and utrophin actin-binding domain 1 structures. The CH1 domain is highly similar to the actin-bound utrophin structure and structural homology suggests that the `closed' single-chain conformation opens during actin binding to mitigate steric clashes between CH2 and actin.
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Affiliation(s)
- Oakley Streeter
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - Ke Shi
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - Joseph Vavra
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - Hideki Aihara
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - James M. Ervasti
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - Robert Evans
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
| | - Joseph M. Muretta
- Department of Biochemistry, Molecular Biology and BiophysicsUniversity of MinnesotaMinneapolisMN55455USA
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2
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Wang Z, Wang W, Luo Q, Song G. Plectin: Dual Participation in Tumor Progression. Biomolecules 2024; 14:1050. [PMID: 39334817 PMCID: PMC11430127 DOI: 10.3390/biom14091050] [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: 07/27/2024] [Revised: 08/20/2024] [Accepted: 08/21/2024] [Indexed: 09/30/2024] Open
Abstract
The plectin gene can encode a cytoskeletal linking protein, plectin, known for its interaction with three critical components of the cellular cytoskeleton: intermediate filaments, microtubules, and actin filaments. In recent years, more and more studies have reported that plectin is closely related to tumorigenesis and development, exhibiting both tumor-suppressive and tumor-promoting functions. Here, we first introduce the molecular structure and function of plectin, and then we summarize the current understanding of the crucial role of plectin in cancer progression. Finally, we also discuss the possible reasons for the different roles of plectin expression in various types of cancer and highlight the double-edged sword role of plectin in tumor progression. The review aims to deepen the comprehensive understanding of plectin's role in cancer and further help to develop novel therapeutic strategies and drug targets.
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Affiliation(s)
- Zhihui Wang
- College of Bioengineering, Chongqing University, Chongqing 400030, China
- Key Laboratory of Biorheological Science & Technology, Ministry of Education, Chongqing University, Chongqing 400030, China
| | - Wenbin Wang
- College of Bioengineering, Chongqing University, Chongqing 400030, China
- Key Laboratory of Biorheological Science & Technology, Ministry of Education, Chongqing University, Chongqing 400030, China
| | - Qing Luo
- College of Bioengineering, Chongqing University, Chongqing 400030, China
- Key Laboratory of Biorheological Science & Technology, Ministry of Education, Chongqing University, Chongqing 400030, China
| | - Guanbin Song
- College of Bioengineering, Chongqing University, Chongqing 400030, China
- Key Laboratory of Biorheological Science & Technology, Ministry of Education, Chongqing University, Chongqing 400030, China
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3
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Petitjean II, Tran QD, Goutou A, Kabir Z, Wiche G, Leduc C, Koenderink GH. Reconstitution of cytolinker-mediated crosstalk between actin and vimentin. Eur J Cell Biol 2024; 103:151403. [PMID: 38503131 DOI: 10.1016/j.ejcb.2024.151403] [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] [Received: 10/27/2023] [Revised: 03/06/2024] [Accepted: 03/06/2024] [Indexed: 03/21/2024] Open
Abstract
Cell shape and motility are determined by the cytoskeleton, an interpenetrating network of actin filaments, microtubules, and intermediate filaments. The biophysical properties of each filament type individually have been studied extensively by cell-free reconstitution. By contrast, the interactions between the three cytoskeletal networks are relatively unexplored. They are coupled via crosslinkers of the plakin family such as plectin. These are challenging proteins for reconstitution because of their giant size and multidomain structure. Here we engineer a recombinant actin-vimentin crosslinker protein called 'ACTIF' that provides a minimal model system for plectin, recapitulating its modular design with actin-binding and intermediate filament-binding domains separated by a coiled-coil linker for dimerisation. We show by fluorescence and electron microscopy that ACTIF has a high binding affinity for vimentin and actin and creates mixed actin-vimentin bundles. Rheology measurements show that ACTIF-mediated crosslinking strongly stiffens actin-vimentin composites. Finally, we demonstrate the modularity of this approach by creating an ACTIF variant with the intermediate filament binding domain of Adenomatous Polyposis Coli. Our protein engineering approach provides a new cell-free system for the biophysical characterization of intermediate filament-binding crosslinkers and for understanding the mechanical synergy between actin and vimentin in mesenchymal cells.
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Affiliation(s)
- Irene Istúriz Petitjean
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Quang D Tran
- CNRS, Institut Jacques Monod, Université Paris Cité, Paris F-75013, France
| | - Angeliki Goutou
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Zima Kabir
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Gerhard Wiche
- Max Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, Vienna, Austria
| | - Cécile Leduc
- CNRS, Institut Jacques Monod, Université Paris Cité, Paris F-75013, France.
| | - Gijsje H Koenderink
- Department of Bionanoscience & Kavli Institute of Nanoscience, Delft University of Technology, 2629 HZ, Delft, the Netherlands.
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4
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Fischer NG, Aparicio C. Junctional epithelium and hemidesmosomes: Tape and rivets for solving the "percutaneous device dilemma" in dental and other permanent implants. Bioact Mater 2022; 18:178-198. [PMID: 35387164 PMCID: PMC8961425 DOI: 10.1016/j.bioactmat.2022.03.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/14/2022] [Accepted: 03/12/2022] [Indexed: 02/06/2023] Open
Abstract
The percutaneous device dilemma describes etiological factors, centered around the disrupted epithelial tissue surrounding non-remodelable devices, that contribute to rampant percutaneous device infection. Natural percutaneous organs, in particular their extracellular matrix mediating the "device"/epithelium interface, serve as exquisite examples to inspire longer lasting long-term percutaneous device design. For example, the tooth's imperviousness to infection is mediated by the epithelium directly surrounding it, the junctional epithelium (JE). The hallmark feature of JE is formation of hemidesmosomes, cell/matrix adhesive structures that attach surrounding oral gingiva to the tooth's enamel through a basement membrane. Here, the authors survey the multifaceted functions of the JE, emphasizing the role of the matrix, with a particular focus on hemidesmosomes and their five main components. The authors highlight the known (and unknown) effects dental implant - as a model percutaneous device - placement has on JE regeneration and synthesize this information for application to other percutaneous devices. The authors conclude with a summary of bioengineering strategies aimed at solving the percutaneous device dilemma and invigorating greater collaboration between clinicians, bioengineers, and matrix biologists.
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Affiliation(s)
- Nicholas G. Fischer
- MDRCBB-Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, 16-212 Moos Tower, 515 Delaware St. SE, Minneapolis, MN, 55455, USA
| | - Conrado Aparicio
- MDRCBB-Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, 16-212 Moos Tower, 515 Delaware St. SE, Minneapolis, MN, 55455, USA
- Division of Basic Research, Faculty of Odontology, UIC Barcelona – Universitat Internacional de Catalunya, C/. Josep Trueta s/n, 08195, Sant Cugat del Valles, Barcelona, Spain
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), C/. Baldiri Reixac 10-12, 08028, Barcelona, Spain
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5
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Mezawa M, Tsuruya Y, Yamaguchi A, Yamazaki-Takai M, Kono T, Okada H, McCulloch CA, Ogata Y. TNF-α regulates the composition of the basal lamina and cell-matrix adhesions in gingival epithelial cells. Cell Adh Migr 2022; 16:13-24. [PMID: 35137648 PMCID: PMC8837257 DOI: 10.1080/19336918.2022.2029237] [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] [Indexed: 12/03/2022] Open
Abstract
Laminin 5, type 4 collagen, and α6β4 integrin contribute to the formation of hemidesmosomes in the epithelia of periodontal tissues, which is critical for the development and maintenance of the dentogingival junction. As it is not known whether TNF-α alters the composition of the epithelial pericellular matrix, human gingival epithelial cells were cultured in the presence or absence of TNF-α. Treatment with TNF-α accelerated epithelial cell migration and closure of in vitro wounds. These data indicate unexpectedly, that TNF-α promotes the formation of the pericellular matrix around epithelial cells and enhances adhesion of epithelial cells to the underlying matrix, properties which are important for cell migration and the integrity of the dentogingival junction.
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Affiliation(s)
- Masaru Mezawa
- Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan.,Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo, Japan
| | - Yuto Tsuruya
- Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Arisa Yamaguchi
- Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Mizuho Yamazaki-Takai
- Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Tetsuro Kono
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo, Japan.,Department of Histology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Hiroyuki Okada
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo, Japan.,Department of Histology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | | | - Yorimasa Ogata
- Department of Periodontology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan.,Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo, Japan
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6
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Padarti A, Abou-Fadel J, Zhang J. Resurgence of phosphotyrosine binding domains: Structural and functional properties essential for understanding disease pathogenesis. Biochim Biophys Acta Gen Subj 2021; 1865:129977. [PMID: 34391832 DOI: 10.1016/j.bbagen.2021.129977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/30/2021] [Accepted: 07/30/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Phosphotyrosine Binding (PTB) Domains, usually found on scaffold proteins, are pervasive in many cellular signaling pathways. These domains are the second-largest family of phosphotyrosine recognition domains and since their initial discovery, dozens of PTB domains have been structurally determined. SCOPE OF REVIEW Due to its signature sequence flexibility, PTB domains can bind to a large variety of ligands including phospholipids. PTB peptide binding is divided into classical binding (canonical NPXY motifs) and non-classical binding (all other motifs). The first atypical PTB domain was discovered in cerebral cavernous malformation 2 (CCM2) protein, while only one third in size of the typical PTB domain, it remains functionally equivalent. MAJOR CONCLUSIONS PTB domains are involved in numerous signaling processes including embryogenesis, neurogenesis, and angiogenesis, while dysfunction is linked to major disorders including diabetes, hypercholesterolemia, Alzheimer's disease, and strokes. PTB domains may also be essential in infectious processes, currently responsible for the global pandemic in which viral cellular entry is suspected to be mediated through PTB and NPXY interactions. GENERAL SIGNIFICANCE We summarize the structural and functional updates in the PTB domain over the last 20 years in hopes of resurging interest and further analyzing the importance of this versatile domain.
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Affiliation(s)
- Akhil Padarti
- Department of Molecular and Translational Medicine (MTM), Texas Tech University Health Science Center El Paso, 5001 El Paso Drive, El Paso, TX 79905, USA
| | - Johnathan Abou-Fadel
- Department of Molecular and Translational Medicine (MTM), Texas Tech University Health Science Center El Paso, 5001 El Paso Drive, El Paso, TX 79905, USA
| | - Jun Zhang
- Department of Molecular and Translational Medicine (MTM), Texas Tech University Health Science Center El Paso, 5001 El Paso Drive, El Paso, TX 79905, USA.
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7
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Cousin MA, Creighton BA, Breau KA, Spillmann RC, Torti E, Dontu S, Tripathi S, Ajit D, Edwards RJ, Afriyie S, Bay JC, Harper KM, Beltran AA, Munoz LJ, Falcon Rodriguez L, Stankewich MC, Person RE, Si Y, Normand EA, Blevins A, May AS, Bier L, Aggarwal V, Mancini GMS, van Slegtenhorst MA, Cremer K, Becker J, Engels H, Aretz S, MacKenzie JJ, Brilstra E, van Gassen KLI, van Jaarsveld RH, Oegema R, Parsons GM, Mark P, Helbig I, McKeown SE, Stratton R, Cogne B, Isidor B, Cacheiro P, Smedley D, Firth HV, Bierhals T, Kloth K, Weiss D, Fairley C, Shieh JT, Kritzer A, Jayakar P, Kurtz-Nelson E, Bernier RA, Wang T, Eichler EE, van de Laar IMBH, McConkie-Rosell A, McDonald MT, Kemppainen J, Lanpher BC, Schultz-Rogers LE, Gunderson LB, Pichurin PN, Yoon G, Zech M, Jech R, Winkelmann J, Beltran AS, Zimmermann MT, Temple B, Moy SS, Klee EW, Tan QKG, Lorenzo DN. Pathogenic SPTBN1 variants cause an autosomal dominant neurodevelopmental syndrome. Nat Genet 2021; 53:1006-1021. [PMID: 34211179 PMCID: PMC8273149 DOI: 10.1038/s41588-021-00886-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 05/14/2021] [Indexed: 12/22/2022]
Abstract
SPTBN1 encodes βII-spectrin, the ubiquitously expressed β-spectrin that forms micrometer-scale networks associated with plasma membranes. Mice deficient in neuronal βII-spectrin have defects in cortical organization, developmental delay and behavioral deficiencies. These phenotypes, while less severe, are observed in haploinsufficient animals, suggesting that individuals carrying heterozygous SPTBN1 variants may also show measurable compromise of neural development and function. Here we identify heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays; mild to severe intellectual disability; autistic features; seizures; behavioral and movement abnormalities; hypotonia; and variable dysmorphic facial features. We show that these SPTBN1 variants lead to effects that affect βII-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. Our studies define SPTBN1 variants as the genetic basis of a neurodevelopmental syndrome, expand the set of spectrinopathies affecting the brain and underscore the critical role of βII-spectrin in the central nervous system.
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Affiliation(s)
- Margot A Cousin
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA.
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA.
| | - Blake A Creighton
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Keith A Breau
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rebecca C Spillmann
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | | | - Sruthi Dontu
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Swarnendu Tripathi
- Bioinformatics Research and Development Laboratory, Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Deepa Ajit
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Reginald J Edwards
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Simone Afriyie
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Julia C Bay
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Kathryn M Harper
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Alvaro A Beltran
- Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Human Pluripotent Stem Cell Core, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lorena J Munoz
- Human Pluripotent Stem Cell Core, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Liset Falcon Rodriguez
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | | | - Yue Si
- GeneDx, Gaithersburg, MD, USA
| | | | | | - Alison S May
- Department of Neurology, Columbia University, New York, NY, USA
| | - Louise Bier
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
| | - Vimla Aggarwal
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
- Laboratory of Personalized Genomic Medicine, Department of Pathology and Cell Biology, Columbia University, New York, NY, USA
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | | | - Kirsten Cremer
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | - Jessica Becker
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | - Hartmut Engels
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | - Stefan Aretz
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | | | - Eva Brilstra
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Koen L I van Gassen
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Renske Oegema
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Paul Mark
- Spectrum Health Medical Genetics, Grand Rapids, MI, USA
| | - Ingo Helbig
- Division of Neurology, Departments of Neurology and Pediatrics, The Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
- The Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Biomedical and Health Informatics (DBHi), Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Neurology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Sarah E McKeown
- Division of Neurology, Departments of Neurology and Pediatrics, The Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
- The Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Robert Stratton
- Genetics, Driscoll Children's Hospital, Corpus Christi, TX, USA
| | - Benjamin Cogne
- Service de Génétique Médicale, CHU Nantes, Nantes, France
- Université de Nantes, CNRS, INSERM, L'Institut du Thorax, Nantes, France
| | - Bertrand Isidor
- Service de Génétique Médicale, CHU Nantes, Nantes, France
- Université de Nantes, CNRS, INSERM, L'Institut du Thorax, Nantes, France
| | - Pilar Cacheiro
- William Harvey Research Institute, School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Damian Smedley
- William Harvey Research Institute, School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Helen V Firth
- Department of Clinical Genetics, Cambridge University Hospitals, Cambridge, UK
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK
| | - Tatjana Bierhals
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katja Kloth
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Deike Weiss
- Neuropediatrics, Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Cecilia Fairley
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
| | - Joseph T Shieh
- Division of Medical Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Amy Kritzer
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | | | - Evangeline Kurtz-Nelson
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - Raphael A Bernier
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, USA
| | - Tianyun Wang
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Evan E Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Ingrid M B H van de Laar
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Allyn McConkie-Rosell
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Marie T McDonald
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Jennifer Kemppainen
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Brendan C Lanpher
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Laura E Schultz-Rogers
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Lauren B Gunderson
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Pavel N Pichurin
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
| | - Grace Yoon
- Divisions of Clinical/Metabolic Genetics and Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Michael Zech
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
- Institute of Human Genetics, Technical University of Munich, Munich, Germany
| | - Robert Jech
- Department of Neurology, Charles University, 1st Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Juliane Winkelmann
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
- Institute of Human Genetics, Technical University of Munich, Munich, Germany
- Lehrstuhl für Neurogenetik, Technische Universität München, Munich, Germany
- Munich Cluster for Systems Neurology, SyNergy, Munich, Germany
| | - Adriana S Beltran
- Human Pluripotent Stem Cell Core, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michael T Zimmermann
- Bioinformatics Research and Development Laboratory, Genomic Sciences and Precision Medicine Center, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
- Clinical and Translational Sciences Institute, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Brenda Temple
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sheryl S Moy
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Eric W Klee
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - Queenie K-G Tan
- Department of Pediatrics, Duke University Medical Center, Duke University, Durham, NC, USA
| | - Damaris N Lorenzo
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Carolina Institute for Developmental Disabilities, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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8
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Wiche G, Castañón MJ. Cytoskeleton | Intermediate Filament Linker Proteins: Plectin and BPAG1. ENCYCLOPEDIA OF BIOLOGICAL CHEMISTRY III 2021:200-219. [DOI: 10.1016/b978-0-12-819460-7.00263-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2025]
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9
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Liebman C, McColloch A, Rabiei M, Bowling A, Cho M. Mechanics of the cell: Interaction mechanisms and mechanobiological models. CURRENT TOPICS IN MEMBRANES 2020; 86:143-184. [PMID: 33837692 DOI: 10.1016/bs.ctm.2020.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The importance of cell mechanics has long been recognized for the cell development and function. Biomechanics plays an important role in cell metabolism, regulation of mechanotransduction pathways and also modulation of nuclear response. The mechanical properties of the cell are likely determined by, among many others, the cytoskeleton elasticity, membrane tension and cell-substrate adhesion. This coordinated but complex mechanical interplay is required however, for the cell to respond to and influence in a reciprocal manner the chemical and mechanical signals from the extracellular matrix (ECM). In an effort to better and more fully understand the cell mechanics, the role of nuclear mechanics has emerged as an important contributor to the overall cellular mechanics. It is not too difficult to appreciate the physical connection between the nucleus and the cytoskeleton network that may be connected to the ECM through the cell membrane. Transmission of forces from ECM through this connection is essential for a wide range of cellular behaviors and functions such as cytoskeletal reorganization, nuclear movement, cell migration and differentiation. Unlike the cellular mechanics that can be measured using a number of biophysical techniques that were developed in the past few decades, it still remains a daunting challenge to probe the nuclear mechanics directly. In this paper, we therefore aim to provide informative description of the cell membrane and cytoskeleton mechanics, followed by unique computational modeling efforts to elucidate the nucleus-cytoskeleton coupling. Advances in our knowledge of complete cellular biomechanics and mechanotransduction may lead to clinical relevance and applications in mechano-diseases such as atherosclerosis, stem cell-based therapies, and the development of tissue engineered products.
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Affiliation(s)
- Caleb Liebman
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States
| | - Andrew McColloch
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States
| | - Manoochehr Rabiei
- Department of Mechanical and Aerospace Engineering, University of Texas at Arlington, Arlington, TX, United States
| | - Alan Bowling
- Department of Mechanical and Aerospace Engineering, University of Texas at Arlington, Arlington, TX, United States.
| | - Michael Cho
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States.
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10
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Harris AR, Belardi B, Jreij P, Wei K, Shams H, Bausch A, Fletcher DA. Steric regulation of tandem calponin homology domain actin-binding affinity. Mol Biol Cell 2019; 30:3112-3122. [PMID: 31693446 PMCID: PMC6938246 DOI: 10.1091/mbc.e19-06-0317] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 10/03/2019] [Accepted: 10/29/2019] [Indexed: 11/11/2022] Open
Abstract
Tandem calponin homology (CH1-CH2) domains are common actin-binding domains in proteins that interact with and organize the actin cytoskeleton. Despite regions of high sequence similarity, CH1-CH2 domains can have remarkably different actin-binding properties, with disease-associated point mutants known to increase as well as decrease affinity for F-actin. To investigate features that affect CH1-CH2 affinity for F-actin in cells and in vitro, we perturbed the utrophin actin-binding domain by making point mutations at the CH1-CH2 interface, replacing the linker domain, and adding a polyethylene glycol (PEG) polymer to CH2. Consistent with a previous model describing CH2 as a steric negative regulator of actin binding, we find that utrophin CH1-CH2 affinity is both increased and decreased by modifications that change the effective "openness" of CH1 and CH2 in solution. We also identified interface mutations that caused a large increase in affinity without changing solution "openness," suggesting additional influences on affinity. Interestingly, we also observe nonuniform subcellular localization of utrophin CH1-CH2 that depends on the N-terminal flanking region but not on bulk affinity. These observations provide new insights into how small sequence changes, such as those found in diseases, can affect CH1-CH2 binding properties.
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Affiliation(s)
- Andrew R. Harris
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Brian Belardi
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Pamela Jreij
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Kathy Wei
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
| | - Hengameh Shams
- Department of Mechanical Engineering, University of California, Berkeley, Berkeley, CA 94720
| | - Andreas Bausch
- Lehrstuhl für Biophysik (E27), Technische Universität München, Garching 85748, Germany
| | - Daniel A. Fletcher
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Chan Zuckerberg Biohub, San Francisco, CA 94158
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11
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Mezawa M, Tsuruya Y, Yamazaki-Takai M, Takai H, Nakayama Y, McCulloch CA, Ogata Y. IL-1β enhances cell adhesion through laminin 5 and β4 integrin in gingival epithelial cells. J Oral Sci 2019; 61:491-497. [PMID: 31548457 DOI: 10.2334/josnusd.18-0434] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The junctional epithelium and dental enamel adhere because of hemidesmosomes containing laminin 5 and α6β4 integrin, which are important adhesion molecules in the internal basal lamina. Interleukin (IL)-1 is important in the pathogenesis of periodontal disease. IL-1β induces bone resorption by activating osteoclasts; however, its effects on adhesion of epithelial cells remain to be clarified. Laminin β3, β4 integrin, and focal adhesion kinase mRNA levels were higher after 1 h and 3 h of stimulation with IL-1β (1 ng/mL), and IL-1β, type I α1, and type IV α1 collagen mRNA levels were higher after 1 h and lower after 3 h of stimulation with IL-1β. After IL-1β stimulation, colocalization of laminin 5 and β4 integrin was increased after 1 h, colocalization of β4 integrin and plectin was increased after 1 h and decreased after 3 h, and colocalization of β4 integrin and type IV collagen was decreased after 3 h. Wound healing assays showed that IL-1β treatment (3 h) delayed wound healing. These results suggest that IL-1β enhances cell adhesion by altering localization of epithelial adhesion molecules.
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Affiliation(s)
- Masaru Mezawa
- Department of Periodontology, Nihon University School of Dentistry at Matsudo
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo
| | - Yuto Tsuruya
- Department of Periodontology, Nihon University School of Dentistry at Matsudo
| | | | - Hideki Takai
- Department of Periodontology, Nihon University School of Dentistry at Matsudo
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo
| | - Yohei Nakayama
- Department of Periodontology, Nihon University School of Dentistry at Matsudo
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo
| | | | - Yorimasa Ogata
- Department of Periodontology, Nihon University School of Dentistry at Matsudo
- Research Institute of Oral Science, Nihon University School of Dentistry at Matsudo
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12
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Iwamoto DV, Huehn A, Simon B, Huet-Calderwood C, Baldassarre M, Sindelar CV, Calderwood DA. Structural basis of the filamin A actin-binding domain interaction with F-actin. Nat Struct Mol Biol 2018; 25:918-927. [PMID: 30224736 PMCID: PMC6173970 DOI: 10.1038/s41594-018-0128-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 08/03/2018] [Indexed: 11/23/2022]
Abstract
Actin-cross-linking proteins assemble actin filaments into higher-order structures essential for orchestrating cell shape, adhesion, and motility. Missense mutations in the tandem calponin homology domains of their actin-binding domains (ABDs) underlie numerous genetic diseases, but a molecular understanding of these pathologies is hampered by the lack of high-resolution structures of any actin-cross-linking protein bound to F-actin. Here, taking advantage of a high-affinity, disease-associated mutant of the human filamin A (FLNa) ABD, we combine cryo-electron microscopy and functional studies to reveal at near-atomic resolution how the first calponin homology domain (CH1) and residues immediately N-terminal to it engage actin. We further show that reorientation of CH2 relative to CH1 is required to avoid clashes with actin and to expose F-actin-binding residues on CH1. Our data explain localization of disease-associated loss-of-function mutations to FLNaCH1 and gain-of-function mutations to the regulatory FLNaCH2. Sequence conservation argues that this provides a general model for ABD-F-actin binding.
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Affiliation(s)
| | - Andrew Huehn
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Bertrand Simon
- Department of Pharmacology, Yale University, New Haven, CT, USA
| | | | - Massimiliano Baldassarre
- Department of Pharmacology, Yale University, New Haven, CT, USA
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland, UK
| | - Charles V Sindelar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| | - David A Calderwood
- Department of Pharmacology, Yale University, New Haven, CT, USA.
- Department of Cell Biology, Yale University, New Haven, CT, USA.
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13
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Ni Y, Wang X, Yin X, Li Y, Liu X, Wang H, Liu X, Zhang J, Gao H, Shi B, Zhao S. Plectin protects podocytes from adriamycin-induced apoptosis and F-actin cytoskeletal disruption through the integrin α6β4/FAK/p38 MAPK pathway. J Cell Mol Med 2018; 22:5450-5467. [PMID: 30187999 PMCID: PMC6201223 DOI: 10.1111/jcmm.13816] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 01/16/2018] [Accepted: 06/29/2018] [Indexed: 02/06/2023] Open
Abstract
Podocyte injury is an early pathological change characteristic of various glomerular diseases, and apoptosis and F‐actin cytoskeletal disruption are typical features of podocyte injury. In this study, we found that adriamycin (ADR) treatment resulted in typical podocyte injury and repressed plectin expression. Restoring plectin expression protected against ADR‐induced podocyte injury whereas siRNA‐mediated plectin silencing produced similar effects as ADR‐induced podocyte injury, suggesting that plectin plays a key role in preventing podocyte injury. Further analysis showed that plectin repression induced significant integrin α6β4, focal adhesion kinase (FAK) and p38 MAPK phosphorylation. Mutating Y1494, a key tyrosine residue in the integrin β4 subunit, blocked FAK and p38 phosphorylation, thereby alleviating podocyte injury. Inhibitor studies demonstrated that FAK Y397 phosphorylation promoted p38 activation, resulting in podocyte apoptosis and F‐actin cytoskeletal disruption. In vivo studies showed that administration of ADR to rats resulted in significantly increased 24‐hour urine protein levels along with decreased plectin expression and activated integrin α6β4, FAK, and p38. Taken together, these findings indicated that plectin protects podocytes from ADR‐induced apoptosis and F‐actin cytoskeletal disruption by inhibiting integrin α6β4/FAK/p38 pathway activation and that plectin may be a therapeutic target for podocyte injury‐related glomerular diseases.
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Affiliation(s)
- Yongliang Ni
- Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.,Department of Urology, Shandong Provincial Third Hospital, Jinan, Shandong, China
| | - Xin Wang
- Department of Urology, Tengzhou Central People's Hospital affiliated to Jining Medical College, Xintan Road 181, Tengzhou, China
| | - Xiaoxuan Yin
- Department of Traditional Chinese Medicine, Yankuang Group General Hospital, Zoucheng, China
| | - Yan Li
- Department of Urology, Qilu Hospital of Shandong University, Jinan, China
| | - Xigao Liu
- Department of Urology, Qilu Hospital of Shandong University, Jinan, China
| | - Haixin Wang
- Department of Urology, Yankuang Group General Hospital, Zoucheng, China
| | - Xiangjv Liu
- Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University
| | - Jun Zhang
- Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University
| | - Haiqing Gao
- Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University
| | - Benkang Shi
- Department of Urology, Qilu Hospital of Shandong University, Jinan, China
| | - Shaohua Zhao
- Department of Geriatrics, Qilu Hospital of Shandong University, Jinan, Shandong, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University
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14
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Rahimi N. Defenders and Challengers of Endothelial Barrier Function. Front Immunol 2017; 8:1847. [PMID: 29326721 PMCID: PMC5741615 DOI: 10.3389/fimmu.2017.01847] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 12/06/2017] [Indexed: 12/22/2022] Open
Abstract
Regulated vascular permeability is an essential feature of normal physiology and its dysfunction is associated with major human diseases ranging from cancer to inflammation and ischemic heart diseases. Integrity of endothelial cells also play a prominent role in the outcome of surgical procedures and organ transplant. Endothelial barrier function and integrity are regulated by a plethora of highly specialized transmembrane receptors, including claudin family proteins, occludin, junctional adhesion molecules (JAMs), vascular endothelial (VE)-cadherin, and the newly identified immunoglobulin (Ig) and proline-rich receptor-1 (IGPR-1) through various distinct mechanisms and signaling. On the other hand, vascular endothelial growth factor (VEGF) and its tyrosine kinase receptor, VEGF receptor-2, play a central role in the destabilization of endothelial barrier function. While claudins and occludin regulate cell-cell junction via recruitment of zonula occludens (ZO), cadherins via catenin proteins, and JAMs via ZO and afadin, IGPR-1 recruits bullous pemphigoid antigen 1 [also called dystonin (DST) and SH3 protein interacting with Nck90/WISH (SH3 protein interacting with Nck)]. Endothelial barrier function is moderated by the function of transmembrane receptors and signaling events that act to defend or destabilize it. Here, I highlight recent advances that have provided new insights into endothelial barrier function and mechanisms involved. Further investigation of these mechanisms could lead to the discovery of novel therapeutic targets for human diseases associated with endothelial dysfunction.
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Affiliation(s)
- Nader Rahimi
- Department of Pathology, Boston University School of Medicine, Boston, MA, United States
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15
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Structural basis for high-affinity actin binding revealed by a β-III-spectrin SCA5 missense mutation. Nat Commun 2017; 8:1350. [PMID: 29116080 PMCID: PMC5676748 DOI: 10.1038/s41467-017-01367-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 09/08/2017] [Indexed: 12/24/2022] Open
Abstract
Spinocerebellar ataxia type 5 (SCA5) is a neurodegenerative disease caused by mutations in the cytoskeletal protein β-III-spectrin. Previously, a SCA5 mutation resulting in a leucine-to-proline substitution (L253P) in the actin-binding domain (ABD) was shown to cause a 1000-fold increase in actin-binding affinity. However, the structural basis for this increase is unknown. Here, we report a 6.9 Å cryo-EM structure of F-actin complexed with the L253P ABD. This structure, along with co-sedimentation and pulsed-EPR measurements, demonstrates that high-affinity binding caused by the CH2-localized mutation is due to opening of the two CH domains. This enables CH1 to bind actin aided by an unstructured N-terminal region that becomes α-helical upon binding. This helix is required for association with actin as truncation eliminates binding. Collectively, these results shed light on the mechanism by which β-III-spectrin, and likely similar actin-binding proteins, interact with actin, and how this mechanism can be perturbed to cause disease.
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16
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Ortega E, Manso JA, Buey RM, Carballido AM, Carabias A, Sonnenberg A, de Pereda JM. The Structure of the Plakin Domain of Plectin Reveals an Extended Rod-like Shape. J Biol Chem 2016; 291:18643-62. [PMID: 27413182 DOI: 10.1074/jbc.m116.732909] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Indexed: 11/06/2022] Open
Abstract
Plakins are large multi-domain proteins that interconnect cytoskeletal structures. Plectin is a prototypical plakin that tethers intermediate filaments to membrane-associated complexes. Most plakins contain a plakin domain formed by up to nine spectrin repeats (SR1-SR9) and an SH3 domain. The plakin domains of plectin and other plakins harbor binding sites for junctional proteins. We have combined x-ray crystallography with small angle x-ray scattering (SAXS) to elucidate the structure of the plakin domain of plectin, extending our previous analysis of the SR1 to SR5 region. Two crystal structures of the SR5-SR6 region allowed us to characterize its uniquely wide inter-repeat conformational variability. We also report the crystal structures of the SR7-SR8 region, refined to 1.8 Å, and the SR7-SR9 at lower resolution. The SR7-SR9 region, which is conserved in all other plakin domains, forms a rigid segment stabilized by uniquely extensive inter-repeat contacts mediated by unusually long helices in SR8 and SR9. Using SAXS we show that in solution the SR3-SR6 and SR7-SR9 regions are rod-like segments and that SR3-SR9 of plectin has an extended shape with a small central kink. Other plakins, such as bullous pemphigoid antigen 1 and microtubule and actin cross-linking factor 1, are likely to have similar extended plakin domains. In contrast, desmoplakin has a two-segment structure with a central flexible hinge. The continuous versus segmented structures of the plakin domains of plectin and desmoplakin give insight into how different plakins might respond to tension and transmit mechanical signals.
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Affiliation(s)
- Esther Ortega
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain
| | - José A Manso
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain
| | - Rubén M Buey
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain, the Metabolic Engineering Group, Department of Microbiology and Genetics, University of Salamanca, Salamanca, 37007, Spain, and
| | - Ana M Carballido
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain
| | - Arturo Carabias
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain
| | - Arnoud Sonnenberg
- the Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - José M de Pereda
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain,
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17
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Künzli K, Favre B, Chofflon M, Borradori L. One gene but different proteins and diseases: the complexity of dystonin and bullous pemphigoid antigen 1. Exp Dermatol 2015; 25:10-6. [DOI: 10.1111/exd.12877] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Kseniia Künzli
- Department of Dermatology; Inselspital; Bern University Hospital; Bern Switzerland
| | - Bertrand Favre
- Department of Dermatology; Inselspital; Bern University Hospital; Bern Switzerland
| | - Michel Chofflon
- Department of Clinical Neurosciences; Geneva University Hospitals; Geneva Switzerland
| | - Luca Borradori
- Department of Dermatology; Inselspital; Bern University Hospital; Bern Switzerland
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18
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Bandi S, Singh SM, Mallela KMG. Interdomain Linker Determines Primarily the Structural Stability of Dystrophin and Utrophin Tandem Calponin-Homology Domains Rather than Their Actin-Binding Affinity. Biochemistry 2015; 54:5480-8. [PMID: 26288220 DOI: 10.1021/acs.biochem.5b00741] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tandem calponin-homology (CH) domains are the most common actin-binding domains in proteins. However, structural principles underlying their function are poorly understood. These tandem domains exist in multiple conformations with varying degrees of inter-CH-domain interactions. Dystrophin and utrophin tandem CH domains share high sequence similarity (∼82%), yet differ in their structural stability and actin-binding affinity. We examined whether the conformational differences between the two tandem CH domains can explain differences in their stability and actin binding. Dystrophin tandem CH domain is more stable by ∼4 kcal/mol than that of utrophin. Individual CH domains of dystrophin and utrophin have identical structures but differ in their relative orientation around the interdomain linker. We swapped the linkers between dystrophin and utrophin tandem CH domains. Dystrophin tandem CH domain with utrophin linker (DUL) has similar stability as that of utrophin tandem CH domain. Utrophin tandem CH domain with dystrophin linker (UDL) has similar stability as that of dystrophin tandem CH domain. Dystrophin tandem CH domain binds to F-actin ∼30 times weaker than that of utrophin. After linker swapping, DUL has twice the binding affinity as that of dystrophin tandem CH domain. Similarly, UDL has half the binding affinity as that of utrophin tandem CH domain. However, changes in binding free energies due to linker swapping are much lower by an order of magnitude compared to the corresponding changes in unfolding free energies. These results indicate that the linker region determines primarily the structural stability of tandem CH domains rather than their actin-binding affinity.
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Affiliation(s)
- Swati Bandi
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Surinder M Singh
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Krishna M G Mallela
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
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19
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Development of a Novel Green Fluorescent Protein-Based Binding Assay to Study the Association of Plakins with Intermediate Filament Proteins. Methods Enzymol 2015; 569:117-37. [PMID: 26778556 DOI: 10.1016/bs.mie.2015.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protein-protein interactions are fundamental for most biological processes, such as the formation of cellular structures and enzymatic complexes or in signaling pathways. The identification and characterization of protein-protein interactions are therefore essential for understanding the mechanisms and regulation of biological systems. The organization and dynamics of the cytoskeleton, as well as its anchorage to specific sites in the plasma membrane and organelles, are regulated by the plakins. These structurally related proteins anchor different cytoskeletal networks to each other and/or to other cellular structures. The association of several plakins with intermediate filaments (IFs) is critical for maintenance of the cytoarchitecture. Pathogenic mutations in the genes encoding different plakins can lead to dramatic manifestations, occurring principally in the skin, striated muscle, and/or nervous system, due to cytoskeletal disorganization resulting in abnormal cell fragility. Nevertheless, it is still unclear how plakins bind to IFs, although some general rules are slowly emerging. We here describe in detail a recently developed protein-protein fluorescence binding assay, based on the production of recombinant proteins tagged with green fluorescent protein (GFP) and their use as fluid-phase fluorescent ligands on immobilized IF proteins. Using this method, we have been able to assess the ability of C-terminal regions of GFP-tagged plakin proteins to bind to distinct IF proteins and IF domains. This simple and sensitive technique, which is expected to facilitate further studies in this area, can also be potentially employed for any kind of protein-protein interaction studies.
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20
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Molecular architecture and function of the hemidesmosome. Cell Tissue Res 2015; 360:529-44. [PMID: 26017636 PMCID: PMC4452579 DOI: 10.1007/s00441-015-2216-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 11/03/2014] [Indexed: 01/13/2023]
Abstract
Hemidesmosomes are multiprotein complexes that facilitate the stable adhesion of basal epithelial cells to the underlying basement membrane. The mechanical stability of hemidesmosomes relies on multiple interactions of a few protein components that form a membrane-embedded tightly-ordered complex. The core of this complex is provided by integrin α6β4 and P1a, an isoform of the cytoskeletal linker protein plectin that is specifically associated with hemidesmosomes. Integrin α6β4 binds to the extracellular matrix protein laminin-332, whereas P1a forms a bridge to the cytoplasmic keratin intermediate filament network. Other important components are BPAG1e, the epithelial isoform of bullous pemphigoid antigen 1, BPAG2, a collagen-type transmembrane protein and CD151. Inherited or acquired diseases in which essential components of the hemidesmosome are missing or structurally altered result in tissue fragility and blistering. Modulation of hemidesmosome function is of crucial importance for a variety of biological processes, such as terminal differentiation of basal keratinocytes and keratinocyte migration during wound healing and carcinoma invasion. Here, we review the molecular characteristics of the proteins that make up the hemidesmosome core structure and summarize the current knowledge about how their assembly and turnover are regulated by transcriptional and post-translational mechanisms.
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21
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Rezniczek GA, Winter L, Walko G, Wiche G. Functional and Genetic Analysis of Plectin in Skin and Muscle. Methods Enzymol 2015; 569:235-59. [PMID: 26778562 DOI: 10.1016/bs.mie.2015.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Plectin is a large cytoskeletal linker protein with a multitude of functions affecting various cellular processes. It is expressed as several different isoforms from a highly complex gene. Both, this transcript diversity (mainly caused by short 5'-sequences contained in alternative first exons) and the size (>500 kDa) of the resulting proteins, present considerable challenges to plectin researchers. In this chapter, we will consider these problems and offer advice on how to tackle them best. As plectin has been studied most extensively in skin and muscle, we will focus on these types of tissues and describe some selected methods in detail. Foremost, however, we aim to give the readers some good pointers to available tools and into the existing literature.
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Affiliation(s)
- Günther A Rezniczek
- Department of Obstetrics & Gynecology, Marien Hospital Herne, Ruhr-Universität Bochum, Herne, Germany
| | - Lilli Winter
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Gernot Walko
- Centre for Stem Cells & Regenerative Medicine, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Gerhard Wiche
- Department of Biochemistry & Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria.
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22
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Abstract
Plectin and BPAG1e belong to the plakin family of high-molecular-weight proteins that interconnect the cytoskeletal systems and anchor them to junctional complexes. Plectin and BPAG1e are prototypical plakins with a similar tripartite modular structure. The N- and C-terminal regions are built of multiple discrete structural domains, while the central rod domain mediates dimerization by coiled-coil interactions. Owing to the mosaic organization of plakins, the structure of their constituent individual domains or small multi-domain segments can be analyzed isolated. Yet, understanding the integrated function of large regions, oligomers, and heterocomplexes of plakins is difficult due to the large and segmented structure. Here, we describe methods for the production of plectin and BPAG1e samples suitable for structural and biophysical analysis. In addition, we discuss the combination of hybrid methods that yield information at several resolution levels to study the complex, multi-domain, and flexible structure of plakins.
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23
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Alonso-García N, García-Rubio I, Manso JA, Buey RM, Urien H, Sonnenberg A, Jeschke G, de Pereda JM. Combination of X-ray crystallography, SAXS and DEER to obtain the structure of the FnIII-3,4 domains of integrin α6β4. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:969-85. [PMID: 25849406 PMCID: PMC4388270 DOI: 10.1107/s1399004715002485] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 02/05/2015] [Indexed: 03/24/2024]
Abstract
Integrin α6β4 is a major component of hemidesmosomes that mediate the stable anchorage of epithelial cells to the underlying basement membrane. Integrin α6β4 has also been implicated in cell proliferation and migration and in carcinoma progression. The third and fourth fibronectin type III domains (FnIII-3,4) of integrin β4 mediate binding to the hemidesmosomal proteins BPAG1e and BPAG2, and participate in signalling. Here, it is demonstrated that X-ray crystallography, small-angle X-ray scattering and double electron-electron resonance (DEER) complement each other to solve the structure of the FnIII-3,4 region. The crystal structures of the individual FnIII-3 and FnIII-4 domains were solved and the relative arrangement of the FnIII domains was elucidated by combining DEER with site-directed spin labelling. Multiple structures of the interdomain linker were modelled by Monte Carlo methods complying with DEER constraints, and the final structures were selected against experimental scattering data. FnIII-3,4 has a compact and cambered flat structure with an evolutionary conserved surface that is likely to correspond to a protein-interaction site. Finally, this hybrid method is of general application for the study of other macromolecules and complexes.
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Affiliation(s)
- Noelia Alonso-García
- Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas – University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
| | - Inés García-Rubio
- Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
- Centro Universitario de la Defensa, Academia General Militar, Carretera de Huesca s/n, 50090 Zaragoza, Spain
| | - José A. Manso
- Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas – University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
| | - Rubén M. Buey
- Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas – University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
- Metabolic Engineering Group, Department of Microbiology and Genetics, University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
| | - Hector Urien
- Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas – University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
| | - Arnoud Sonnenberg
- Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Gunnar Jeschke
- Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - José M. de Pereda
- Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas – University of Salamanca, Campus Unamuno, 37007 Salamanca, Spain
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Cheng CC, Lai YCC, Lai YS, Hsu YH, Chao WT, Sia KC, Tseng YH, Liu YH. Transient knockdown-mediated deficiency in plectin alters hepatocellular motility in association with activated FAK and Rac1-GTPase. Cancer Cell Int 2015; 15:29. [PMID: 25774093 PMCID: PMC4358909 DOI: 10.1186/s12935-015-0177-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 02/16/2015] [Indexed: 11/17/2022] Open
Abstract
Background Plectin is one of the cytolinker proteins that play a crucial role in maintaining the integrity of cellular architecture. It is a component of desmosome complexes connecting cytoskeletal proteins and trans-membrane molecules. In epithelial cells, plectin connects cytokeratins and integrin α6β4 in hemidesmosomes anchoring to the extracellular matrix. In addition to the function of molecular adherent, plectin has been reported to exhibit functions affecting cellular signals and responsive activities mediated by stress, cellular migration, polarization as well as the dynamic movement of actin filaments. Plectin deficiency in hepatocellular carcinoma results in abnormal expression of cytokeratin 18 and disassembled hemidesmosome. Therefore, it is hypothesized that the plectin deficiency-mediated collapse of cytoskeleton may modulate cellular motility that is associated with consequent metastatic behaviors of cancer cells. Methods and results The cellular motility of plectin-deficient Chang liver cells generated by transient knockdown were analyzed by trans-well migration assay and the results revealed a higher migration rate. The confocal microscopy also demonstrated less organized and more polarized morphology as well as more focal adhesion kinase activity in comparison with that of the mock Chang liver cells. Furthermore, plectin-knockdown in Chang liver cells was associated with a higher activity of Rac1-GTPase in accordance with the results of the Rac1 pull-down assay. The immunohistochemical assay on human hepatocellular carcinoma showed that the expression of focal adhesion kinase was increased in the invasive front of tumor. Conclusion Plectin-deficient human hepatic cells exhibit higher cell motility associated with increase in focal adhesion kinase activity that are comparable to the properties of invasive hepatocellular carcinoma.
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Affiliation(s)
- Chiung-Chi Cheng
- Department of Pathology, Chang Bing Show Chwan Memorial Hospital, No. 6, Lugong Rd., Lugang Town, Changhua County 505 Taiwan ; Center for General Education, Providence University, Taichung City, Taiwan
| | - Yen-Chang Clark Lai
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan
| | - Yih-Shyong Lai
- Department of Pathology, Chang Bing Show Chwan Memorial Hospital, No. 6, Lugong Rd., Lugang Town, Changhua County 505 Taiwan
| | - Yung-Hsiang Hsu
- Department of Pathology, Tzu Chi University, Hualien County, Taiwan
| | - Wei-Ting Chao
- Department of Life Science, Tunghai University, Taichung City, Taiwan
| | - Kee-Chin Sia
- Department of Life Science, Tunghai University, Taichung City, Taiwan
| | - Yu-Hui Tseng
- Department of Life Science, Tunghai University, Taichung City, Taiwan
| | - Yi-Hsiang Liu
- Department of Pathology, Chang Bing Show Chwan Memorial Hospital, No. 6, Lugong Rd., Lugang Town, Changhua County 505 Taiwan ; Department of Pathology, Tzu Chi University, Hualien County, Taiwan
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25
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Song JG, Kostan J, Drepper F, Knapp B, de Almeida Ribeiro E, Konarev PV, Grishkovskaya I, Wiche G, Gregor M, Svergun DI, Warscheid B, Djinović-Carugo K. Structural insights into Ca2+-calmodulin regulation of Plectin 1a-integrin β4 interaction in hemidesmosomes. Structure 2015; 23:558-570. [PMID: 25703379 PMCID: PMC4353693 DOI: 10.1016/j.str.2015.01.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 12/24/2014] [Accepted: 01/06/2015] [Indexed: 02/02/2023]
Abstract
The mechanical stability of epithelial cells, which protect organisms from harmful external factors, is maintained by hemidesmosomes via the interaction between plectin 1a (P1a) and integrin α6β4. Binding of calcium-calmodulin (Ca(2+)-CaM) to P1a together with phosphorylation of integrin β4 disrupts this complex, resulting in disassembly of hemidesmosomes. We present structures of the P1a actin binding domain either in complex with the N-ter lobe of Ca(2+)-CaM or with the first pair of integrin β4 fibronectin domains. Ca(2+)-CaM binds to the N-ter isoform-specific tail of P1a in a unique manner, via its N-ter lobe in an extended conformation. Structural, cell biology, and biochemical studies suggest the following model: binding of Ca(2+)-CaM to an intrinsically disordered N-ter segment of plectin converts it to an α helix, which repositions calmodulin to displace integrin β4 by steric repulsion. This model could serve as a blueprint for studies aimed at understanding how Ca(2+)-CaM or EF-hand motifs regulate F-actin-based cytoskeleton.
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Affiliation(s)
- Jae-Geun Song
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Julius Kostan
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Friedel Drepper
- Department of Functional Proteomics and Biochemistry, Institute of Biology II and BIOSS Centre for Biological Signaling Studies, University of Freiburg, Schaenzlestrasse 1, D-79104 Freiburg, Germany
| | - Bettina Knapp
- Department of Functional Proteomics and Biochemistry, Institute of Biology II and BIOSS Centre for Biological Signaling Studies, University of Freiburg, Schaenzlestrasse 1, D-79104 Freiburg, Germany
| | - Euripedes de Almeida Ribeiro
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Petr V Konarev
- EMBL-Hamburg c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany
| | - Irina Grishkovskaya
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Gerhard Wiche
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohrgasse 9, A-1030 Vienna, Austria
| | - Martin Gregor
- Department of Integrative Biology, Institute of Molecular Genetics of the ASCR, Vídeňská 1083, Prague 4 CZ-14220, Czech Republic
| | - Dmitri I Svergun
- EMBL-Hamburg c/o DESY, Notkestrasse 85, D-22603 Hamburg, Germany
| | - Bettina Warscheid
- Department of Functional Proteomics and Biochemistry, Institute of Biology II and BIOSS Centre for Biological Signaling Studies, University of Freiburg, Schaenzlestrasse 1, D-79104 Freiburg, Germany
| | - Kristina Djinović-Carugo
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter (VBC), Campus Vienna Biocenter 5, A-1030 Vienna, Austria; Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana, Slovenia.
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26
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Molecular architecture and function of the hemidesmosome. Cell Tissue Res 2014; 360:363-78. [PMID: 25487405 PMCID: PMC4544487 DOI: 10.1007/s00441-014-2061-z] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 11/03/2014] [Indexed: 01/07/2023]
Abstract
Hemidesmosomes are multiprotein complexes that facilitate the stable adhesion of basal epithelial cells to the underlying basement membrane. The mechanical stability of hemidesmosomes relies on multiple interactions of a few protein components that form a membrane-embedded tightly-ordered complex. The core of this complex is provided by integrin α6β4 and P1a, an isoform of the cytoskeletal linker protein plectin that is specifically associated with hemidesmosomes. Integrin α6β4 binds to the extracellular matrix protein laminin-332, whereas P1a forms a bridge to the cytoplasmic keratin intermediate filament network. Other important components are BPAG1e, the epithelial isoform of bullous pemphigoid antigen 1, BPAG2, a collagen-type transmembrane protein and CD151. Inherited or acquired diseases in which essential components of the hemidesmosome are missing or structurally altered result in tissue fragility and blistering. Modulation of hemidesmosome function is of crucial importance for a variety of biological processes, such as terminal differentiation of basal keratinocytes and keratinocyte migration during wound healing and carcinoma invasion. Here, we review the molecular characteristics of the proteins that make up the hemidesmosome core structure and summarize the current knowledge about how their assembly and turnover are regulated by transcriptional and post-translational mechanisms.
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27
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Sutoh Yoneyama M, Hatakeyama S, Habuchi T, Inoue T, Nakamura T, Funyu T, Wiche G, Ohyama C, Tsuboi S. Vimentin intermediate filament and plectin provide a scaffold for invadopodia, facilitating cancer cell invasion and extravasation for metastasis. Eur J Cell Biol 2014; 93:157-69. [PMID: 24810881 DOI: 10.1016/j.ejcb.2014.03.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/26/2014] [Accepted: 03/26/2014] [Indexed: 01/17/2023] Open
Abstract
To investigate the molecular mechanisms of cancer metastasis, we have isolated a high-metastatic bladder cancer cell subpopulation from a low-metastatic cell line by using an in vivo selection system. Cells in the subpopulation showed a high ability to form invadopodia, the filamentous actin (F-actin)-based membrane protrusions that play an essential role in cancer cell invasion. Analysis of the gene expression profile revealed that the expression of an intermediate filament (IF) protein, vimentin and a cytoskeletal linker protein, plectin was up-regulated in the high-metastatic subpopulation compared with the low metastatic cell line. Here we report a novel role of vimentin IF and plectin in metastasis. In invasive bladder cancer cells, the vimentin IF-plectin-invadopodia F-actin link was formed. Disruption of this link severely impaired invadopodia formation, reducing the capacities of extracellular matrix degradation, transendothelial migration and metastasis. In addition, the vimentin assembly into the filaments was required for invadopodia formation. Our results suggest that plectin anchoring invadopodia to vimentin IF scaffolds and stabilizes invadopodia, which is a critical molecular process for cancer cell invasion and extravasation for metastasis.
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Affiliation(s)
- Mihoko Sutoh Yoneyama
- Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shingo Hatakeyama
- Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Tomonori Habuchi
- Department of Urology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Takamitsu Inoue
- Department of Urology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Toshiya Nakamura
- Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, Hirosaki, Japan
| | - Tomihisa Funyu
- Department of Cancer Immunology and Cell Biology, Oyokyo Kidney Research Institute, Hirosaki, Japan
| | - Gerhard Wiche
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, Vienna 1030, Austria
| | - Chikara Ohyama
- Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shigeru Tsuboi
- Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan; Department of Cancer Immunology and Cell Biology, Oyokyo Kidney Research Institute, Hirosaki, Japan.
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28
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Castañón MJ, Walko G, Winter L, Wiche G. Plectin-intermediate filament partnership in skin, skeletal muscle, and peripheral nerve. Histochem Cell Biol 2013; 140:33-53. [PMID: 23748243 PMCID: PMC3695321 DOI: 10.1007/s00418-013-1102-0] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2013] [Indexed: 01/13/2023]
Abstract
Plectin is a large, 500-kDa, intermediate filament (IF)-associated protein. It acts as a cytoskeletal crosslinker and signaling scaffold, affecting mechanical as well as dynamic properties of the cytoskeleton. As a member of the plakin family of cytolinker proteins, plectin has a multidomain structure that is responsible for its vast binding portfolio. It not only binds to all types of IFs, actin filaments and microtubules, but also to transmembrane receptors, proteins of the subplasma membrane protein skeleton, components of the nuclear envelope, and several kinases with known roles in migration, proliferation, and energy metabolism of cells. Due to alternative splicing, plectin is expressed as various isoforms with differing N-terminal heads that dictate their differential subcellular targeting. Through specific interactions with other proteins at their target sites and their ability to bind to all types of IFs, plectin molecules provide strategically located IF anchorage sites within the cytoplasm of cells. In this review, we will present an overview of the structural features and functional properties of plectin and discuss recent progress in defining the role of its isoforms in stress-prone tissues and the implicated diseases, with focus on skin, skeletal muscle, and Schwann cells of peripheral nerve.
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Affiliation(s)
- Maria J. Castañón
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
| | - Gernot Walko
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
- Present Address: Centre for Stem Cells and Regenerative Medicine, King’s College London School of Medicine, 28th Floor, Tower Wing, Guy’s Hospital, Great Maze Pond, London, SE1 9RT UK
| | - Lilli Winter
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
- Present Address: Institute of Neuropathology, University Hospital Erlangen, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Gerhard Wiche
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna, 1030 Vienna, Austria
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29
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The N-terminal actin-binding tandem calponin-homology (CH) domain of dystrophin is in a closed conformation in solution and when bound to F-actin. Biophys J 2013. [PMID: 23199925 DOI: 10.1016/j.bpj.2012.08.066] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Deficiency of the vital muscle protein dystrophin triggers Duchenne/Becker muscular dystrophy, but the structure-function relationship of dystrophin is poorly understood. To date, molecular structures of three dystrophin domains have been determined, of which the N-terminal actin-binding domain (N-ABD or ABD1) is of particular interest. This domain is composed of two calponin-homology (CH) domains, which form an important class of ABDs in muscle proteins. A previously determined x-ray structure indicates that the dystrophin N-ABD is a domain-swapped dimer, with each monomer adopting an extended, open conformation in which the two CH domains do not interact. This structure is controversial because it contradicts functional studies and known structures of similar ABDs from other muscle proteins. Here, we investigated the solution conformation of the dystrophin N-ABD using a very simple and elegant technique of pyrene excimer fluorescence. Using the wild-type protein, which contains two cysteines, and the corresponding single-cysteine mutants, we show that the protein is a monomer in solution and is in a closed conformation in which the two CH domains seem to interact, as observed from the excimer fluorescence of pyrene-labeled wild-type protein. Excimer fluorescence was also observed in its actin-bound form, indicating that the dystrophin N-ABD binds to F-actin in a closed conformation. Comparison of the dystrophin N-ABD conformation with other ABDs indicates that the tandem CH domains in general may be monomeric in solution and predominantly occur in closed conformation, whereas their actin-bound conformations may differ.
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30
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Maia V, Ortiz-Rivero S, Sanz M, Gutierrez-Berzal J, Alvarez-Fernández I, Gutierrez-Herrero S, de Pereda JM, Porras A, Guerrero C. C3G forms complexes with Bcr-Abl and p38α MAPK at the focal adhesions in chronic myeloid leukemia cells: implication in the regulation of leukemic cell adhesion. Cell Commun Signal 2013; 11:9. [PMID: 23343344 PMCID: PMC3629710 DOI: 10.1186/1478-811x-11-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 01/18/2013] [Indexed: 12/17/2022] Open
Abstract
Background Previous studies by our group and others have shown that C3G interacts with Bcr-Abl through its SH3-b domain. Results In this work we show that C3G and Bcr-Abl form complexes with the focal adhesion (FA) proteins CrkL, p130Cas, Cbl and Abi1 through SH3/SH3-b interactions. The association between C3G and Bcr-Abl decreased upon Abi1 or p130Cas knock-down in K562 cells, which suggests that Abi1 and p130Cas are essential partners in this interaction. On the other hand, C3G, Abi1 or Cbl knock-down impaired adhesion to fibronectin, while p130Cas silencing enhanced it. C3G, Cbl and p130Cas-SH3-b domains interact directly with common proteins involved in the regulation of cell adhesion and migration. Immunoprecipitation and immunofluorescence studies revealed that C3G form complexes with the FA proteins paxillin and FAK and their phosphorylated forms. Additionally, C3G, Abi1, Cbl and p130Cas regulate the expression and phosphorylation of paxillin and FAK. p38α MAPK also participates in the regulation of adhesion in chronic myeloid leukemia cells. It interacts with C3G, CrkL, FAK and paxillin and regulates the expression of paxillin, CrkL and α5 integrin, as well as paxillin phosphorylation. Moreover, double knock-down of C3G/p38α decreased adhesion to fibronectin, similarly to the single silencing of one of these genes, either C3G or p38α. These suggest that C3G and p38α MAPK are acting through a common pathway to regulate cell adhesion in K562 cells, as previously described for the regulation of apoptosis. Conclusions Our results indicate that C3G-p38αMAPK pathway regulates K562 cell adhesion through the interaction with FA proteins and Bcr-Abl, modulating the formation of different protein complexes at FA.
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Affiliation(s)
- Vera Maia
- Centro de Investigación del Cáncer, IBMCC, CSIC-Universidad de Salamanca, Salamanca, Spain.
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31
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Winter L, Wiche G. The many faces of plectin and plectinopathies: pathology and mechanisms. Acta Neuropathol 2013; 125:77-93. [PMID: 22864774 DOI: 10.1007/s00401-012-1026-0] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 07/12/2012] [Accepted: 07/23/2012] [Indexed: 12/20/2022]
Abstract
Plectin, a giant multifunctional cytolinker protein, plays a crucial role in stabilizing and orchestrating intermediate filament networks in cells. Mutations in the human plectin gene result in multiple diseases manifesting with muscular dystrophy, skin blistering, and signs of neuropathy. The most common disease caused by plectin deficiency is epidermolysis bullosa simplex (EBS)-MD, a rare autosomal-recessive skin blistering disorder with late-onset muscular dystrophy. EBS-MD patients and plectin-deficient mice display pathologic desmin-positive protein aggregates, degenerated myofibrils, and mitochondrial abnormalities, the hallmarks of myofibrillar myopathies. In addition to EBS-MD, plectin mutations have been shown to cause EBS-MD with a myasthenic syndrome, limb-girdle muscular dystrophy type 2Q, EBS with pyloric atresia, and EBS-Ogna. This review focuses on clinical and pathological manifestations of these plectinopathies. It addresses especially plectin's role in skeletal muscle, where a loss of muscle fiber integrity and profound changes of myofiber cytoarchitecture are observed in its absence. Furthermore, the highly complex genetic and molecular structure of plectin is discussed; a high number of differentially spliced exons give rise to a variety of different isoforms, which fulfill distinct functions in different cell types and tissues. Plectin's abilities to act as a dynamic organizer of intermediate filament networks and to interact with a multitude of different interaction partners are the basis for its function as a scaffolding platform for proteins involved in signaling. Finally, the article addresses a series of genetically manipulated mouse lines that were generated to serve as powerful models to study functional and molecular consequences of plectin gene defects.
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Affiliation(s)
- Lilli Winter
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr. Bohrgasse 9, 1030 Vienna, Austria
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Karashima T, Tsuruta D, Hamada T, Ishii N, Ono F, Hashikawa K, Ohyama B, Natsuaki Y, Fukuda S, Koga H, Sogame R, Nakama T, Dainichi T, Hashimoto T. Interaction of plectin and intermediate filaments. J Dermatol Sci 2012; 66:44-50. [DOI: 10.1016/j.jdermsci.2012.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 01/06/2012] [Accepted: 01/16/2012] [Indexed: 12/21/2022]
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Frijns E, Kuikman I, Litjens S, Raspe M, Jalink K, Ports M, Wilhelmsen K, Sonnenberg A. Phosphorylation of threonine 1736 in the C-terminal tail of integrin β4 contributes to hemidesmosome disassembly. Mol Biol Cell 2012; 23:1475-85. [PMID: 22357621 PMCID: PMC3327322 DOI: 10.1091/mbc.e11-11-0957] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
T1736 is a novel phosphorylation site on the integrin β4 subunit that is phosphorylated downstream of protein kinase C and EGF receptor activation and is a substrate for protein kinase D1 in vitro and in cells. It contributes to the regulation of HD dynamics through modulating the association of β4 with plectin. During wound healing, hemidesmome disassembly enables keratinocyte migration and proliferation. Hemidesmosome dynamics are altered downstream of epidermal growth factor (EGF) receptor activation, following the phosphorylation of integrin β4 residues S1356 and S1364, which reduces the interaction with plectin; however, this event is insufficient to drive complete hemidesmome disassembly. In the studies reported here, we used a fluorescence resonance energy transfer–based assay to demonstrate that the connecting segment and carboxy-terminal tail of the β4 cytoplasmic domain interact, which facilitates the formation of a binding platform for plectin. In addition, analysis of a β4 mutant containing a phosphomimicking aspartic acid residue at T1736 in the C-tail suggests that phosphorylation of this residue regulates the interaction with the plectin plakin domain. The aspartic acid mutation of β4 T1736 impaired hemidesmosome formation in junctional epidermolysis associated with pyloric atresia/β4 keratinocytes. Furthermore, we show that T1736 is phosphorylated downstream of protein kinase C and EGF receptor activation and is a substrate for protein kinase D1 in vitro and in cells, which requires its translocation to the plasma membrane and subsequent activation. In conclusion, we identify T1736 as a novel phosphorylation site that contributes to the regulation of hemidesmome disassembly, a dynamically regulated process involving the concerted phosphorylation of multiple β4 residues.
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Affiliation(s)
- Evelyne Frijns
- Division of Cell Biology, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
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Broderick MJF, Bobkov A, Winder SJ. Utrophin ABD binds to F-actin in an open conformation. FEBS Open Bio 2012; 2:6-11. [PMID: 23650574 PMCID: PMC3642092 DOI: 10.1016/j.fob.2012.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 01/18/2012] [Indexed: 11/20/2022] Open
Abstract
Structural analyses of actin binding regions comprising tandem calponin homology domains alone and when bound to F-actin have revealed a number of different conformations with calponin homology domains in ‘open’ and ‘closed’ positions. In an attempt to resolve these issues we have examined the properties of the utrophin actin binding domain in open and closed conformations in order to verify the conformation when bound to F-actin. Locking the actin binding domain in a closed conformation using engineered cysteine residues in each calponin homology domain reduced the affinity for F-actin without affecting the stoichiometry furthermore differential scanning calorimetry experiments revealed a reduction in melting temperature on binding to actin. The data suggest the amino-terminal utrophin actin binding domain is in an open conformation in solution and when bound to F-actin.
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Key Words
- ABD, actin binding domain
- Actin binding domain
- CD, circular dichroism
- CH, calponin homology
- Calponin homology domain
- DSC, differential scanning calorimetry
- Differential scanning calorimetry
- Dystrophin
- EM, electron microscopy
- F-actin, filamentous actin
- NTCB, 2-nitro-5-thiocyanobenzoic acid
- SDS-PAGE, sodium dodecyl sulphate poly-acrylamide electrophoresis
- Spectrin
- Tm, melting temperature
- UTR261, utrophin residues 1-261
- α-Actinin
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Affiliation(s)
- Mike J F Broderick
- Department of Biomedical Science, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK ; IBLS, University of Glasgow, Glasgow G12 8QQ, UK
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Henderson DM, Lin AY, Thomas DD, Ervasti JM. The carboxy-terminal third of dystrophin enhances actin binding activity. J Mol Biol 2011; 416:414-24. [PMID: 22226838 DOI: 10.1016/j.jmb.2011.12.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 12/19/2011] [Accepted: 12/20/2011] [Indexed: 10/14/2022]
Abstract
Dystrophin is an actin binding protein that is thought to stabilize the cardiac and skeletal muscle cell membranes during contraction. Here, we investigated the contributions of each dystrophin domain to actin binding function. Cosedimentation assays and pyrene-actin fluorescence experiments confirmed that a fragment spanning two-thirds of the dystrophin molecule [from N-terminal actin binding domain (ABD) 1 through ABD2] bound actin filaments with high affinity and protected filaments from forced depolymerization, but was less effective in both assays than full-length dystrophin. While a construct encoding the C-terminal third of dystrophin displayed no specific actin binding activity or competition with full-length dystrophin, our data show that it confers an unexpected regulation of actin binding by the N-terminal two-thirds of dystrophin when present in cis. Time-resolved phosphorescence anisotropy experiments demonstrated that the presence of the C-terminal third of dystrophin in cis also influences actin interaction by restricting actin rotational amplitude. We propose that the C-terminal region of dystrophin allosterically stabilizes an optimal actin binding conformation of dystrophin.
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Affiliation(s)
- Davin M Henderson
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
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36
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Nonlinear viscoelasticity of actin transiently cross-linked with mutant α-actinin-4. J Mol Biol 2011; 411:1062-71. [PMID: 21762701 DOI: 10.1016/j.jmb.2011.06.049] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/27/2011] [Accepted: 06/29/2011] [Indexed: 01/17/2023]
Abstract
Filamentous actin and associated actin binding proteins play an essential role in governing the mechanical properties of eukaryotic cells. They can also play a critical role in disease; for example, mutations in α-actinin-4 (Actn4), a dynamic actin cross-linking protein, cause proteinuric disease in humans and mice. Amino acid substitutions strongly affect the binding affinity and protein structure of Actn4. To study the physical impact of such substitutions on the underlying cytoskeletal network, we examine the bulk mechanical behavior of in vitro actin networks cross-linked with wild-type and mutant Actn4. These networks exhibit a complex viscoelastic response and are characterized by fluid-like behavior at the longest timescales, a feature that can be quantitatively accounted for through a model governed by dynamic cross-linking. The elastic behavior of the network is highly nonlinear, becoming much stiffer with applied stress. This nonlinear elastic response is also highly sensitive to the mutations of Actn4. In particular, we observe that actin networks cross-linked with Actn4 bearing the disease-causing K255E mutation are more brittle, with a lower breaking stress in comparison to networks cross-linked with wild-type Actn4. Furthermore, a mutation that ablates the first actin binding site (ABS1) in Actn4 abrogates the network's ability to stress-stiffen is standard nomenclature. These changes in the mechanical properties of actin networks cross-linked with mutant Actn4 may represent physical determinants of the underlying disease mechanism in inherited focal segmental glomerulosclerosis.
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Ortega E, Buey RM, Sonnenberg A, de Pereda JM. The structure of the plakin domain of plectin reveals a non-canonical SH3 domain interacting with its fourth spectrin repeat. J Biol Chem 2011; 286:12429-38. [PMID: 21288893 PMCID: PMC3069446 DOI: 10.1074/jbc.m110.197467] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 12/29/2010] [Indexed: 11/06/2022] Open
Abstract
Plectin belongs to the plakin family of cytoskeletal crosslinkers, which is part of the spectrin superfamily. Plakins contain an N-terminal conserved region, the plakin domain, which is formed by an array of spectrin repeats (SR) and a Src-homology 3 (SH3), and harbors binding sites for junctional proteins. We have combined x-ray crystallography and small angle x-ray scattering (SAXS) to elucidate the structure of the central region of the plakin domain of plectin, which corresponds to the SR3, SR4, SR5, and SH3 domains. The crystal structures of the SR3-SR4 and SR4-SR5-SH3 fragments were determined to 2.2 and 2.95 Å resolution, respectively. The SH3 of plectin presents major alterations as compared with canonical Pro-rich binding SH3 domains, suggesting that plectin does not recognize Pro-rich motifs. In addition, the SH3 binding site is partially occluded by an intramolecular contact with the SR4. Residues of this pseudo-binding site and the SR4/SH3 interface are conserved within the plakin family, suggesting that the structure of this part of the plectin molecule is similar to that of other plakins. We have created a model for the SR3-SR4-SR5-SH3 region, which agrees well with SAXS data in solution. The three SRs form a semi-flexible rod that is not altered by the presence of the SH3 domain, and it is similar to those found in spectrins. The flexibility of the plakin domain, in analogy with spectrins, might contribute to the role of plakins in maintaining the stability of tissues subject to mechanical stress.
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Affiliation(s)
- Esther Ortega
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, Campus Unamuno, E-37007 Salamanca, Spain
| | - Rubén M. Buey
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, Campus Unamuno, E-37007 Salamanca, Spain
- the Laboratory of Biomolecular Research, the Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland, and
| | - Arnoud Sonnenberg
- the Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - José M. de Pereda
- From the Instituto de Biología Molecular y Celular del Cancer, Consejo Superior de Investigaciones Científicas, University of Salamanca, Campus Unamuno, E-37007 Salamanca, Spain
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38
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Postel R, Ketema M, Kuikman I, de Pereda JM, Sonnenberg A. Nesprin-3 augments peripheral nuclear localization of intermediate filaments in zebrafish. J Cell Sci 2011; 124:755-64. [PMID: 21303928 DOI: 10.1242/jcs.081174] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The outer nuclear membrane protein nesprin-3 binds the cytoskeletal linker protein plectin, which are proposed to anchor the intermediate filaments to the nuclear envelope. To investigate the function of nesprin-3 in vivo, we used the zebrafish as a vertebrate model system. Zebrafish nesprin-3 is expressed at the nuclear envelope of epidermal and skeletal muscle cells during development. Unexpectedly, loss of nesprin-3 did not affect embryonic development, viability or fertility. However, nesprin-3-deficient zebrafish embryos showed a reduced concentration of intermediate filaments around the nucleus. Additional analysis revealed the presence of two nesprin-3 isoforms in zebrafish, nesprin-3α and nesprin-3β. Nesprin-3β is only expressed during early development and lacks seven amino acids in its first spectrin repeat that are crucial for plectin binding and recruitment to the nuclear envelope. These seven amino acids are highly conserved and we showed that residues R43 and L44 within this motif are required for plectin binding. Furthermore, several residues in the actin-binding domain of plectin that are crucial for binding to the integrin β4 subunit are also important for the binding to nesprin-3α, indicating partial overlapping binding sequences for nesprin-3α and integrin β4. All this shows that nesprin-3 is dispensable for normal development in zebrafish, but important for mediating the association of the intermediate filament system with the nucleus in vivo.
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Affiliation(s)
- Ruben Postel
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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39
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Falces J, Arregi I, Konarev PV, Urbaneja MA, Svergun DI, Taneva SG, Bañuelos S. Recognition of nucleoplasmin by its nuclear transport receptor importin α/β: insights into a complete import complex. Biochemistry 2010; 49:9756-69. [PMID: 20925424 DOI: 10.1021/bi101179g] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Nuclear import of the pentameric histone chaperone nucleoplasmin (NP) is mediated by importin α, which recognizes its nuclear localization sequence (NLS), and importin β, which interacts with α and is in charge of the translocation of the NP/α/β complex through the nuclear pore. Herein, we characterize the assembly of a functional transport complex formed by full-length NP with importin α/β. Isothermal titration calorimetry (ITC) was used to analyze the thermodynamics of the interactions of importin α with β, α with NP, and the α/β heterodimer with NP. Our data show that binding of both importin α and α/β to NP is governed by a favorable enthalpic contribution and that NP can accommodate up to five importin molecules per NP pentamer. Phosphomimicking mutations of NP, which render the protein active in histone chaperoning, do not modulate the interaction with importin. Using small-angle X-ray scattering, we model the α/β heterodimer, NP/α, and NP/α/β solution structures, which reveal a glimpse of a complete nuclear import complex with an oligomeric cargo protein. The set of alternative models, equally well fitting the scattering data, yields asymmetric elongated particles that might represent consecutive geometries the complex can adopt when stepping through the nuclear pore.
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Affiliation(s)
- Jorge Falces
- Unidad de Biofísica (CSIC/UPV-EHU), Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco, POB 644, 48080 Bilbao, Spain
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40
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Le Goff E, Vallentin A, Harmand PO, Aldrian-Herrada G, Rebière B, Roy C, Benyamin Y, Lebart MC. Characterization of L-plastin interaction with beta integrin and its regulation by micro-calpain. Cytoskeleton (Hoboken) 2010; 67:286-96. [PMID: 20183869 DOI: 10.1002/cm.20442] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Recent evidences suggest that plastin/fimbrin is more than a simple actin cross-linking molecule. In this context and based on the fact that other members of the same family interact with transmembrane proteins, such as integrins, we have investigated a possible interaction between L-plastin and integrins. By combining coimmunoprecipitation of endogenous proteins and in vitro techniques based on solid phase and solution assays, we demonstrate that L-plastin is an additional binding partner for the beta-chain of integrin and confirmed that both proteins display some colocalization. We then show that L-plastin binds to the cytoplasmic domain of beta1 integrin and to beta1 and beta2 peptides. Using recombinant L-plastin domains, we demonstrate that the integrin-binding sites are not located in NH(2) terminal part of L-plastin but rather in the two actin-binding domains. Using pull-down, cross-linking experiments, and enzyme-linked immunosorbent assay, we show that the L-plastin/integrin complex is regulated by mu-calpain cleavage and is not directly dissociated by calcium. Indeed, despite the ability of calpain to cleave both proteins, only the cleavage of beta integrin hindered the formation of the L-plastin/integrin complex. We discuss these results in the light of the three-dimensional structure of the actin-binding domains of L-plastin.
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Affiliation(s)
- E Le Goff
- UMR CNRS 5554, Institut des Sciences de l'Evolution, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier, Cedex 05, France
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41
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The carboxyterminal EF domain of erythroid alpha-spectrin is necessary for optimal spectrin-actin binding. Blood 2010; 116:2600-7. [PMID: 20585040 DOI: 10.1182/blood-2009-12-260612] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Spectrin and protein 4.1R crosslink F-actin, forming the membrane skeleton. Actin and 4.1R bind to one end of β-spectrin. The adjacent end of α-spectrin, called the EF domain, is calmodulin-like, with calcium-dependent and calcium-independent EF hands. The severely anemic sph(1J)/sph(1J) mouse has very fragile red cells and lacks the last 13 amino acids in the EF domain, implying that the domain is critical for skeletal integrity. To test this, we constructed a minispectrin heterodimer from the actin-binding domain, the EF domain, and 4 adjacent spectrin repeats in each chain. The minispectrin bound to F-actin in the presence of native human protein 4.1R. Formation of the spectrin-actin-4.1R complex was markedly attenuated when the minispectrin contained the shortened sph(1J) α-spectrin. The α-spectrin deletion did not interfere with spectrin heterodimer assembly or 4.1R binding but abolished the binary interaction between spectrin and F-actin. The data show that the α-spectrin EF domain greatly amplifies the function of the β-spectrin actin-binding domain (ABD) in forming the spectrin-actin-4.1R complex. A model, based on the structure of α-actinin, suggests that the EF domain modulates the function of the ABD and that the C-terminal EF hands (EF(34)) may bind to the linker that connects the ABD to the first spectrin repeat.
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42
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Cheltsov AV, Aoyagi M, Aleshin A, Yu ECW, Gilliland T, Zhai D, Bobkov AA, Reed JC, Liddington RC, Abagyan R. Vaccinia virus virulence factor N1L is a novel promising target for antiviral therapeutic intervention. J Med Chem 2010; 53:3899-906. [PMID: 20441222 DOI: 10.1021/jm901446n] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The 14 kDa homodimeric N1L protein is a potent vaccinia and variola (smallpox) virulence factor. It is not essential for viral replication, but it causes a strong attenuation of viral production in culture when deleted. The N1L protein is predicted to contain the BH3-like binding domain characteristic of Bcl-2 family proteins, and it is able to bind the BH3 peptides. Its overexpression has been reported to prevent infected cells from committing apoptosis. Therefore, interfering with the N1L apoptotic blockade may be a legitimate therapeutic strategy affecting the viral growth. By using in silico ligand docking and an array of in vitro assays, we have identified submicromolar (600 nM) N1L antagonists belonging to the family of polyphenols. Their affinity is comparable to that of the BH3 peptides (70-1000 nM). We have also identified the natural polyphenol resveratrol as a moderate N1L inhibitor. Finally, we show that our ligands efficiently inhibit growth of vaccinia virus.
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Affiliation(s)
- Anton V Cheltsov
- Infectious and Inflammatory Disease Center, Burnham Institute for Medical Research, La Jolla, California 92037, USA
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43
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Galkin VE, Orlova A, Salmazo A, Djinovic-Carugo K, Egelman EH. Opening of tandem calponin homology domains regulates their affinity for F-actin. Nat Struct Mol Biol 2010; 17:614-6. [PMID: 20383143 PMCID: PMC2921939 DOI: 10.1038/nsmb.1789] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 02/19/2010] [Indexed: 11/16/2022]
Abstract
Many actin-binding proteins contain calponin homology (CH) domains, but the manner in which these domains interact with F-actin has been controversial. Crystal structures have shown the tandem CH domains of alpha-actinin to be in a compact, closed conformation, but the interpretations of complexes of such tandem CH domains with F-actin have been ambiguous. We show that the tandem CH domains of alpha-actinin bind F-actin in an open conformation, explaining mutations that cause human diseases and suggesting that the opening of these domains may be one of the main regulatory mechanisms for proteins with tandem CH domains.
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Affiliation(s)
- Vitold E. Galkin
- Deaprtment of Biochemistry and Molecular Genetics, University of Virginia Medical Center, Box 800733, Charlottesville, VA 22908-0733, U.S.A
| | - Albina Orlova
- Deaprtment of Biochemistry and Molecular Genetics, University of Virginia Medical Center, Box 800733, Charlottesville, VA 22908-0733, U.S.A
| | - Anita Salmazo
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria
| | - Kristina Djinovic-Carugo
- Department for Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Campus Vienna Biocenter 5, A-1030 Vienna, Austria
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, 1000 Ljubljana, Slovenia
| | - Edward H. Egelman
- Deaprtment of Biochemistry and Molecular Genetics, University of Virginia Medical Center, Box 800733, Charlottesville, VA 22908-0733, U.S.A
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44
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Doolittle JM, Gomez SM. Structural similarity-based predictions of protein interactions between HIV-1 and Homo sapiens. Virol J 2010; 7:82. [PMID: 20426868 PMCID: PMC2877021 DOI: 10.1186/1743-422x-7-82] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 04/28/2010] [Indexed: 01/05/2023] Open
Abstract
Background In the course of infection, viruses such as HIV-1 must enter a cell, travel to sites where they can hijack host machinery to transcribe their genes and translate their proteins, assemble, and then leave the cell again, all while evading the host immune system. Thus, successful infection depends on the pathogen's ability to manipulate the biological pathways and processes of the organism it infects. Interactions between HIV-encoded and human proteins provide one means by which HIV-1 can connect into cellular pathways to carry out these survival processes. Results We developed and applied a computational approach to predict interactions between HIV and human proteins based on structural similarity of 9 HIV-1 proteins to human proteins having known interactions. Using functional data from RNAi studies as a filter, we generated over 2000 interaction predictions between HIV proteins and 406 unique human proteins. Additional filtering based on Gene Ontology cellular component annotation reduced the number of predictions to 502 interactions involving 137 human proteins. We find numerous known interactions as well as novel interactions showing significant functional relevance based on supporting Gene Ontology and literature evidence. Conclusions Understanding the interplay between HIV-1 and its human host will help in understanding the viral lifecycle and the ways in which this virus is able to manipulate its host. The results shown here provide a potential set of interactions that are amenable to further experimental manipulation as well as potential targets for therapeutic intervention.
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Affiliation(s)
- Janet M Doolittle
- Department of Computer Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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45
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Abstract
The dynamic remolding of the actin cytoskeleton is a critical part of most cellular activities, and malfunction of cytoskeletal proteins results in various human diseases. The transition between two forms of actin, monomeric or G-actin and filamentous or F-actin, is tightly regulated in time and space by a large number of signaling, scaffolding and actin-binding proteins (ABPs). New ABPs are constantly being discovered in the post-genomic era. Most of these proteins are modular, integrating actin binding, protein-protein interaction, membrane-binding, and signaling domains. In response to extracellular signals, often mediated by Rho family GTPases, ABPs control different steps of actin cytoskeleton assembly, including filament nucleation, elongation, severing, capping, and depolymerization. This review summarizes structure-function relationships among ABPs in the regulation of actin cytoskeleton assembly.
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Affiliation(s)
- Sung Haeng Lee
- Chosun University School of Medicine, Department of Cellular and Molecular Medicine, Gwangju 501-759, Korea.
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46
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Rezniczek GA, Walko G, Wiche G. Plectin gene defects lead to various forms of epidermolysis bullosa simplex. Dermatol Clin 2010; 28:33-41. [PMID: 19945614 DOI: 10.1016/j.det.2009.10.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Plectin is an important organizer of the keratin filament cytoskeleton in basal keratinocytes. It is essential for anchoring these filaments to the extracellular matrix via hemidesmosomal integrins. Loss of plectin or incorrect function of the protein due to mutations in its gene can lead to various forms of the skin blistering disease, epidermolysis bullosa simplex. Severity and subtype of the disease is dependent on the specific mutation and can be associated with (late-onset) muscular dystrophy or pyloric atresia. Mouse models mimicking the human phenotypes allow detailed study of plectin function.
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Affiliation(s)
- Günther A Rezniczek
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Dr.-Bohr-Gasse 9, 1030 Vienna, Austria
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47
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Kondrikov D, Fonseca FV, Elms S, Fulton D, Black SM, Block ER, Su Y. Beta-actin association with endothelial nitric-oxide synthase modulates nitric oxide and superoxide generation from the enzyme. J Biol Chem 2010; 285:4319-27. [PMID: 19946124 PMCID: PMC2836036 DOI: 10.1074/jbc.m109.063172] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 11/20/2009] [Indexed: 11/06/2022] Open
Abstract
Protein-protein interactions represent an important post-translational mechanism for endothelial nitric-oxide synthase (eNOS) regulation. We have previously reported that beta-actin is associated with eNOS oxygenase domain and that association of eNOS with beta-actin increases eNOS activity and nitric oxide (NO) production. In the present study, we found that beta-actin-induced increase in NO production was accompanied by decrease in superoxide formation. A synthetic actin-binding sequence (ABS) peptide 326 with amino acid sequence corresponding to residues 326-333 of human eNOS, one of the putative ABSs, specifically bound to beta-actin and prevented eNOS association with beta-actin in vitro. Peptide 326 also prevented beta-actin-induced decrease in superoxide formation and increase in NO and L-citrulline production. A modified peptide 326 replacing hydrophobic amino acids leucine and tryptophan with neutral alanine was unable to interfere with eNOS-beta-actin binding and to prevent beta-actin-induced changes in NO and superoxide formation. Site-directed mutagenesis of the actin-binding domain of eNOS replacing leucine and tryptophan with alanine yielded an eNOS mutant that exhibited reduced eNOS-beta-actin association, decreased NO production, and increased superoxide formation in COS-7 cells. Disruption of eNOS-beta-actin interaction in endothelial cells using ABS peptide 326 resulted in decreased NO production, increased superoxide formation, and decreased endothelial monolayer wound repair, which was prevented by PEG-SOD and NO donor NOC-18. Taken together, this novel finding indicates that beta-actin binding to eNOS through residues 326-333 in the eNOS protein results in shifting the enzymatic activity from superoxide formation toward NO production. Modulation of NO and superoxide formation from eNOS by beta-actin plays an important role in endothelial function.
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Affiliation(s)
| | | | | | - David Fulton
- From the Department of Pharmacology and Toxicology
- Vascular Biology Center, and
| | | | - Edward R. Block
- the Department of Medicine, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Yunchao Su
- From the Department of Pharmacology and Toxicology
- Department of Medicine
- Vascular Biology Center, and
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta, Georgia 30912 and
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48
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de Pereda JM, Ortega E, Alonso-García N, Gómez-Hernández M, Sonnenberg A. Advances and perspectives of the architecture of hemidesmosomes: lessons from structural biology. Cell Adh Migr 2009; 3:361-4. [PMID: 19736524 DOI: 10.4161/cam.3.4.9525] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Hemidesmosomes (HD) are adhesive protein complexes that mediate stable attachment of basal epithelial cells to the underlying basement membrane. The organization of HDs relies on a complex network of protein-protein interactions, in which integrin alpha6beta4 and plectin play an essential role. Here we summarize the current knowledge of the structure of hemidesmosomal proteins, which includes the structures of the first and second fibronectin type III (FnIII) domains and the calx-beta domain of the integrin beta4 subunit, the actin binding domain of plectin, and two non-overlapping pairs of spectrin repeats of plectin and BPAG1e. Binding of plectin to the beta4 subunit is critical for the formation and the stability of HDs. The recent 3D structure of the primary complex between the integrin beta4 subunit and plectin has provided a first insight into the macromolecular recognition mechanisms responsible for HD assembly. Two missense mutations in beta4 linked to non lethal forms of epidermolysis bullosa map on the plectin-binding surface. Finally, the formation of the beta4-plectin complex induces conformational changes in beta4 and plectin, suggesting that their interaction may be subject to allosteric regulation.
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Affiliation(s)
- José M de Pereda
- Instituto de Biología Molecular y Celular del Cáncer, Consejo Superior de Investigaciones Científicas-Universidad de Salamanca, Campus Unamuno, Salamanca, Spain.
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O'Neill GM. The coordination between actin filaments and adhesion in mesenchymal migration. Cell Adh Migr 2009; 3:355-7. [PMID: 19684475 DOI: 10.4161/cam.3.4.9468] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mesenchymal cell motility is characterized by a polarized distribution of actin filaments, with a network of short branched actin filaments at the leading edge, and polymers of actin filaments arranged into distinct classes of actin stress fibers behind the leading edge. Importantly, the distinct actin filaments are characteristically associated with discrete adhesion structures and both the adhesions and the actin filaments are co-ordinately regulated during cell migration. While it has long been known that these macromolecular structures are intimately linked in cells, precisely how they are co-ordinately regulated is presently unknown. Live imaging data now suggests that the focal adhesions may act as sites of actin polymerization resulting in the generation of tension-bearing actin bundles of actin filaments (stress fibers). Moreover, a picture is emerging to suggest that the tropomyosin family of proteins that can determine actin filament dynamics may also play a key role in determining the transition between adhesion states. Molecules such as the tropomyosins are therefore tantalizing candidates to orchestrate the coordination of actin and adhesion dynamics during mesenchymal cell migration.
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Affiliation(s)
- Geraldine M O'Neill
- Focal Adhesion Biology Group, Oncology Research Unit, The Kids Research Institute at the Children's Hospital at Westmead, Westmead, NSW, Australia.
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50
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Nabet B, Tsai A, Tobias JW, Carstens RP. Identification of a putative network of actin-associated cytoskeletal proteins in glomerular podocytes defined by co-purified mRNAs. PLoS One 2009; 4:e6491. [PMID: 19652713 PMCID: PMC2714980 DOI: 10.1371/journal.pone.0006491] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 06/25/2009] [Indexed: 11/30/2022] Open
Abstract
The glomerular podocyte is a highly specialized and polarized kidney cell type that contains major processes and foot processes that extend from the cell body. Foot processes from adjacent podocytes form interdigitations with those of adjacent cells, thereby creating an essential intercellular junctional domain of the renal filtration barrier known as the slit diaphragm. Interesting parallels have been drawn between the slit diaphragm and other sites of cell-cell contact by polarized cells. Notably mutations in several genes encoding proteins localized to the foot processes can lead to proteinuria and kidney failure. Mutations in the Wilm's tumor gene (WT1) can also lead to kidney disease and one isoform of WT1, WT1(+KTS), has been proposed to regulate gene expression post-transcriptionally. We originally sought to identify mRNAs associated with WT1(+KTS) through an RNA immunoprecipitation and microarray approach, hypothesizing that the proteins encoded by these mRNAs might be important for podocyte morphology and function. We identified a subset of mRNAs that were remarkably enriched for transcripts encoding actin-binding proteins and other cytoskeletal proteins including several that are localized at or near the slit diaphragm. Interestingly, these mRNAs included those of α-actinin-4 and non-muscle myosin IIA that are mutated in genetic forms of kidney disease. However, isolation of the mRNAs occurred independently of the expression of WT1, suggesting that the identified mRNAs were serendipitously co-purified on the basis of co-association in a common subcellular fraction. Mass spectroscopy revealed that other components of the actin cytoskeleton co-purified with these mRNAs, namely actin, tubulin, and elongation factor 1α. We propose that these mRNAs encode a number of proteins that comprise a highly specialized protein interactome underlying the slit diaphragm. Collectively, these gene products and their interactions may prove to be important for the structural integrity of the actin cytoskeleton in podocytes as well as other polarized cell types.
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Affiliation(s)
- Behnam Nabet
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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