1
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Bougaran P, Bautch VL. Life at the crossroads: the nuclear LINC complex and vascular mechanotransduction. Front Physiol 2024; 15:1411995. [PMID: 38831796 PMCID: PMC11144885 DOI: 10.3389/fphys.2024.1411995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 05/02/2024] [Indexed: 06/05/2024] Open
Abstract
Vascular endothelial cells line the inner surface of all blood vessels, where they are exposed to polarized mechanical forces throughout their lifespan. Both basal substrate interactions and apical blood flow-induced shear stress regulate blood vessel development, remodeling, and maintenance of vascular homeostasis. Disruption of these interactions leads to dysfunction and vascular pathologies, although how forces are sensed and integrated to affect endothelial cell behaviors is incompletely understood. Recently the endothelial cell nucleus has emerged as a prominent force-transducing organelle that participates in vascular mechanotransduction, via communication to and from cell-cell and cell-matrix junctions. The LINC complex, composed of SUN and nesprin proteins, spans the nuclear membranes and connects the nuclear lamina, the nuclear envelope, and the cytoskeleton. Here we review LINC complex involvement in endothelial cell mechanotransduction, describe unique and overlapping functions of each LINC complex component, and consider emerging evidence that two major SUN proteins, SUN1 and SUN2, orchestrate a complex interplay that extends outward to cell-cell and cell-matrix junctions and inward to interactions within the nucleus and chromatin. We discuss these findings in relation to vascular pathologies such as Hutchinson-Gilford progeria syndrome, a premature aging disorder with cardiovascular impairment. More knowledge of LINC complex regulation and function will help to understand how the nucleus participates in endothelial cell force sensing and how dysfunction leads to cardiovascular disease.
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Affiliation(s)
- Pauline Bougaran
- Department of Biology, The University of North Carolina, Chapel Hill, NC, United States
| | - Victoria L. Bautch
- Department of Biology, The University of North Carolina, Chapel Hill, NC, United States
- McAllister Heart Institute, The University of North Carolina, Chapel Hill, NC, United States
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2
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Luo J, Huang H, Qiao H, Tan J, Chen W, Zhang M, Ruiz-Linares A, Wang J, Yang Y, Jin L, Headon DJ, Wang S. GWASs Identify Genetic Loci Associated with Human Scalp Hair Whorl Direction. J Invest Dermatol 2023; 143:2065-2068.e10. [PMID: 37565938 DOI: 10.1016/j.jid.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 08/12/2023]
Affiliation(s)
- Junyu Luo
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - He Huang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China; Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Science, Fudan University, Shanghai, China
| | - Hui Qiao
- Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Science, Fudan University, Shanghai, China
| | - Jingze Tan
- Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Science, Fudan University, Shanghai, China
| | - Wenyan Chen
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Manfei Zhang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China; Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Andrés Ruiz-Linares
- Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Science, Fudan University, Shanghai, China; Aix-Marseille Université, Centre National de la Recherche Scientifique (CNRS), EFS, Anthropologie Bio-Culturelle, Droit, Ethique et Santé (ADES), Marseille, France; Department of Genetics, Evolution and Environment, UCL Division of Biosciences, University College London, London, United Kingdom
| | - Jiucun Wang
- State Key Laboratory of Genetic Engineering, Human Phenome Institute, Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, China; Fudan-Taizhou Institute of Health Sciences, Taizhou, China; Research Unit of Dissecting the Population Genetics and Developing New Technologies for Treatment and Prevention of Skin Phenotypes and Dermatological Diseases (2019RU058), Chinese Academy of Medical Sciences, Shanghai, China
| | - Yajun Yang
- Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Science, Fudan University, Shanghai, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering, Human Phenome Institute, Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, China; Fudan-Taizhou Institute of Health Sciences, Taizhou, China; Research Unit of Dissecting the Population Genetics and Developing New Technologies for Treatment and Prevention of Skin Phenotypes and Dermatological Diseases (2019RU058), Chinese Academy of Medical Sciences, Shanghai, China
| | - Denis J Headon
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Sijia Wang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China.
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3
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Gao K, Gao Z, Xia M, Li H, Di J. Role of plectin and its interacting molecules in cancer. Med Oncol 2023; 40:280. [PMID: 37632650 DOI: 10.1007/s12032-023-02132-4] [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: 04/24/2023] [Accepted: 07/20/2023] [Indexed: 08/28/2023]
Abstract
Plectin, as the cytolinker and scaffolding protein, are widely expressed and abundant in many tissues, and has involved in various cellular activities contributing to tumorigenesis, such as cell adhesion, migration, and signal transduction. Due to the specific expression and differential localization of plectin in cancer, most researchers focus on the role of plectin in cancer, and it has emerged as a potent driver of malignant hallmarks in many human cancers, which provides the possibility for plectin to be widely used as a biomarker and therapeutic target in the early diagnosis and targeted drug delivery of the disease. However, there is still a lack of systematic review on the interaction molecules and mechanism of plectin. Herein, we summarized the structure, expression and function of plectin, and mainly focused on recent studies on the functional and physical interactions between plectin and its interacting molecules, shedding light on the potential of targeting plectin for cancer therapy.
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Affiliation(s)
- Keyu Gao
- Department of Urology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Zhimin Gao
- Department of Urology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China
| | - Mingyi Xia
- Cancer Institute, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
- Center of Clinical Oncology, The Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221002, Jiangsu, China
- Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China
| | - Hailong Li
- Department of Urology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, 221002, Jiangsu, China.
| | - Jiehui Di
- Cancer Institute, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China.
- Center of Clinical Oncology, The Affiliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou, 221002, Jiangsu, China.
- Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou, 221004, Jiangsu, China.
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4
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Sharma R, Hetzer MW. Disulfide bond in SUN2 regulates dynamic remodeling of LINC complexes at the nuclear envelope. Life Sci Alliance 2023; 6:e202302031. [PMID: 37188462 PMCID: PMC10193101 DOI: 10.26508/lsa.202302031] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/02/2023] [Accepted: 05/02/2023] [Indexed: 05/17/2023] Open
Abstract
The LINC complex tethers the cell nucleus to the cytoskeleton to regulate mechanical forces during cell migration, differentiation, and various diseases. The function of LINC complexes relies on the interaction between highly conserved SUN and KASH proteins that form higher-order assemblies capable of load bearing. These structural details have emerged from in vitro assembled LINC complexes; however, the principles of in vivo assembly remain obscure. Here, we report a conformation-specific SUN2 antibody as a tool to visualize LINC complex dynamics in situ. Using imaging, biochemical, and cellular methods, we find that conserved cysteines in SUN2 undergo KASH-dependent inter- and intra-molecular disulfide bond rearrangements. Disruption of the SUN2 terminal disulfide bond compromises SUN2 localization, turnover, LINC complex assembly in addition to cytoskeletal organization and cell migration. Moreover, using pharmacological and genetic perturbations, we identify components of the ER lumen as SUN2 cysteines redox state regulators. Overall, we provide evidence for SUN2 disulfide bond rearrangement as a physiologically relevant structural modification that regulates LINC complex functions.
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Affiliation(s)
- Rahul Sharma
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Martin W Hetzer
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, USA
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5
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Kucińska MK, Fedry J, Galli C, Morone D, Raimondi A, Soldà T, Förster F, Molinari M. TMX4-driven LINC complex disassembly and asymmetric autophagy of the nuclear envelope upon acute ER stress. Nat Commun 2023; 14:3497. [PMID: 37311770 DOI: 10.1038/s41467-023-39172-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 05/31/2023] [Indexed: 06/15/2023] Open
Abstract
The endoplasmic reticulum (ER) is an organelle of nucleated cells that produces proteins, lipids and oligosaccharides. ER volume and activity are increased upon induction of unfolded protein responses (UPR) and are reduced upon activation of ER-phagy programs. A specialized domain of the ER, the nuclear envelope (NE), protects the cell genome with two juxtaposed lipid bilayers, the inner and outer nuclear membranes (INM and ONM) separated by the perinuclear space (PNS). Here we report that expansion of the mammalian ER upon homeostatic perturbations results in TMX4 reductase-driven disassembly of the LINC complexes connecting INM and ONM and in ONM swelling. The physiologic distance between ONM and INM is restored, upon resolution of the ER stress, by asymmetric autophagy of the NE, which involves the LC3 lipidation machinery, the autophagy receptor SEC62 and the direct capture of ONM-derived vesicles by degradative LAMP1/RAB7-positive endolysosomes in a catabolic pathway mechanistically defined as micro-ONM-phagy.
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Affiliation(s)
- Marika K Kucińska
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland
- Department of Biology, Swiss Federal Institute of Technology, CH-8093, Zurich, Switzerland
| | - Juliette Fedry
- Structural Biochemistry, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CG, Utrecht, The Netherlands
| | - Carmela Galli
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland
| | - Diego Morone
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3000, Bern, Switzerland
| | - Andrea Raimondi
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland
- Experimental Imaging Center, San Raffaele Scientific Institute, I-20132, Milan, Italy
| | - Tatiana Soldà
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland
| | - Friedrich Förster
- Structural Biochemistry, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CG, Utrecht, The Netherlands
| | - Maurizio Molinari
- Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Institute for Research in Biomedicine, CH-6500, Bellinzona, Switzerland.
- School of Life Sciences, École Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland.
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6
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Buglak DB, Bougaran P, Kulikauskas MR, Liu Z, Monaghan-Benson E, Gold AL, Marvin AP, Burciu A, Tanke NT, Oatley M, Ricketts SN, Kinghorn K, Johnson BN, Shiau CE, Rogers S, Guilluy C, Bautch VL. Nuclear SUN1 stabilizes endothelial cell junctions via microtubules to regulate blood vessel formation. eLife 2023; 12:83652. [PMID: 36989130 PMCID: PMC10059686 DOI: 10.7554/elife.83652] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 03/10/2023] [Indexed: 03/30/2023] Open
Abstract
Endothelial cells line all blood vessels, where they coordinate blood vessel formation and the blood-tissue barrier via regulation of cell-cell junctions. The nucleus also regulates endothelial cell behaviors, but it is unclear how the nucleus contributes to endothelial cell activities at the cell periphery. Here, we show that the nuclear-localized linker of the nucleoskeleton and cytoskeleton (LINC) complex protein SUN1 regulates vascular sprouting and endothelial cell-cell junction morphology and function. Loss of murine endothelial Sun1 impaired blood vessel formation and destabilized junctions, angiogenic sprouts formed but retracted in SUN1-depleted sprouts, and zebrafish vessels lacking Sun1b had aberrant junctions and defective cell-cell connections. At the cellular level, SUN1 stabilized endothelial cell-cell junctions, promoted junction function, and regulated contractility. Mechanistically, SUN1 depletion altered cell behaviors via the cytoskeleton without changing transcriptional profiles. Reduced peripheral microtubule density, fewer junction contacts, and increased catastrophes accompanied SUN1 loss, and microtubule depolymerization phenocopied effects on junctions. Depletion of GEF-H1, a microtubule-regulated Rho activator, or the LINC complex protein nesprin-1 rescued defective junctions of SUN1-depleted endothelial cells. Thus, endothelial SUN1 regulates peripheral cell-cell junctions from the nucleus via LINC complex-based microtubule interactions that affect peripheral microtubule dynamics and Rho-regulated contractility, and this long-range regulation is important for proper blood vessel sprouting and junction integrity.
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Affiliation(s)
- Danielle B Buglak
- Curriculum in Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Pauline Bougaran
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Molly R Kulikauskas
- Curriculum in Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Ziqing Liu
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Elizabeth Monaghan-Benson
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State UniversityRaleighUnited States
| | - Ariel L Gold
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Allison P Marvin
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Andrew Burciu
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Natalie T Tanke
- Curriculum in Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Morgan Oatley
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Shea N Ricketts
- Department of Pathology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Karina Kinghorn
- Curriculum in Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Bryan N Johnson
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Celia E Shiau
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Stephen Rogers
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Christophe Guilluy
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State UniversityRaleighUnited States
| | - Victoria L Bautch
- Curriculum in Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
- Department of Biology, The University of North Carolina at Chapel HillChapel HillUnited States
- McAllister Heart Institute, The University of North Carolina at Chapel HillChapel HillUnited States
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7
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Shaiken TE, Grimm SL, Siam M, Williams A, Rezaeian AH, Kraushaar D, Ricco E, Robertson MJ, Coarfa C, Jain A, Malovannaya A, Stossi F, Opekun AR, Price AP, Dubrulle J. Transcriptome, proteome, and protein synthesis within the intracellular cytomatrix. iScience 2023; 26:105965. [PMID: 36824274 PMCID: PMC9941065 DOI: 10.1016/j.isci.2023.105965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 11/07/2022] [Accepted: 01/06/2023] [Indexed: 01/15/2023] Open
Abstract
Despite the knowledge that protein translation and various metabolic reactions that create and sustain cellular life occur in the cytoplasm, the structural organization within the cytoplasm remains unclear. Recent models indicate that cytoplasm contains viscous fluid and elastic solid phases. We separated these viscous fluid and solid elastic compartments, which we call the cytosol and cytomatrix, respectively. The distinctive composition of the cytomatrix included structural proteins, ribosomes, and metabolome enzymes. High-throughput analysis revealed unique biosynthetic pathways within the cytomatrix. Enrichment of biosynthetic pathways in the cytomatrix indicated the presence of immobilized biocatalysis. Enzymatic immobilization and segregation can surmount spatial impediments, and the local pathway segregation may form cytoplasmic organelles. Protein translation was reprogrammed within the cytomatrix under the restriction of protein synthesis by drug treatment. The cytosol and cytomatrix are an elaborately interconnected network that promotes operational flexibility in healthy cells and the survival of malignant cells.
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Affiliation(s)
- Tattym E. Shaiken
- Department of Medicine-Gastroenterology and Hepatology Section, Michael E DeBakey Veteran’s Affairs Medical Center, Baylor College of Medicine, Houston, TX 77030, USA
- PeriNuc Labs, University of Houston Technology Bridge, Houston, TX 77023, USA
| | - Sandra L. Grimm
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mohamad Siam
- Department of Medicine-Gastroenterology and Hepatology Section, Michael E DeBakey Veteran’s Affairs Medical Center, Baylor College of Medicine, Houston, TX 77030, USA
- PeriNuc Labs, University of Houston Technology Bridge, Houston, TX 77023, USA
| | - Amanda Williams
- Department of Medicine-Gastroenterology and Hepatology Section, Michael E DeBakey Veteran’s Affairs Medical Center, Baylor College of Medicine, Houston, TX 77030, USA
- PeriNuc Labs, University of Houston Technology Bridge, Houston, TX 77023, USA
| | - Abdol-Hossein Rezaeian
- PeriNuc Labs, University of Houston Technology Bridge, Houston, TX 77023, USA
- Department of Drug Discovery and Biomedical Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Daniel Kraushaar
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | - Emily Ricco
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Cristian Coarfa
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | - Antrix Jain
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | - Anna Malovannaya
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
| | - Fabio Stossi
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Antone R. Opekun
- Department of Medicine-Gastroenterology and Hepatology Section, Michael E DeBakey Veteran’s Affairs Medical Center, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alyssa P. Price
- Department of Medicine-Gastroenterology and Hepatology Section, Michael E DeBakey Veteran’s Affairs Medical Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Julien Dubrulle
- Advanced Technology Cores, Baylor College of Medicine, Houston, TX 77030, USA
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8
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Regulation of Kinase Signaling Pathways by α6β4-Integrins and Plectin in Prostate Cancer. Cancers (Basel) 2022; 15:cancers15010149. [PMID: 36612146 PMCID: PMC9818203 DOI: 10.3390/cancers15010149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/19/2022] [Accepted: 12/24/2022] [Indexed: 12/28/2022] Open
Abstract
Hemidesmosomes (HDs) are adhesive structures that ensure stable anchorage of cells to the basement membrane. They are formed by α6β4-integrin heterodimers and linked to intermediate filaments via plectin. It has been reported that one of the most common events during the pathogenesis of prostate cancer (PCa) is the loss of HD organization. While the expression levels of β4-integrins are strongly reduced, the expression levels of α6-integrins and plectin are maintained or even elevated, and seem to promote tumorigenic properties of PCa cells, such as proliferation, invasion, metastasis, apoptosis- and drug-resistance. In this review, we discuss the potential mechanisms of how HD components might contribute to various cellular signaling pathways to promote prostate carcinogenesis. Moreover, we summarize the current knowledge on the involvement of α6β4-integrins and plectin in PCa initiation and progression.
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9
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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: 18] [Impact Index Per Article: 9.0] [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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10
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Stenvall CGA, Nyström JH, Butler-Hallissey C, Jansson T, Heikkilä TRH, Adam SA, Foisner R, Goldman RD, Ridge KM, Toivola DM. Cytoplasmic keratins couple with and maintain nuclear envelope integrity in colonic epithelial cells. Mol Biol Cell 2022; 33:ar121. [PMID: 36001365 PMCID: PMC9634972 DOI: 10.1091/mbc.e20-06-0387] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Keratin intermediate filaments convey mechanical stability and protection against stress to epithelial cells. Keratins are essential for colon health, as seen in keratin 8 knockout (K8-/-) mice exhibiting a colitis phenotype. We hypothesized that keratins support the nuclear envelope and lamina in colonocytes. K8-/- colonocytes in vivo exhibit significantly decreased levels of lamins A/C, B1, and B2 in a colon-specific and cell-intrinsic manner. CRISPR/Cas9- or siRNA-mediated K8 knockdown in Caco-2 cells similarly decreased lamin levels, which recovered after reexpression of K8 following siRNA treatment. Nuclear area was not decreased, and roundness was only marginally increased in cells without K8. Down-regulation of K8 in adult K8flox/flox;Villin-CreERt2 mice following tamoxifen administration significantly decreased lamin levels at day 4 when K8 levels had reduced to 40%. K8 loss also led to reduced levels of plectin, LINC complex, and lamin-associated proteins. While keratins were not seen in the nucleoplasm without or with leptomycin B treatment, keratins were found intimately located at the nuclear envelope and complexed with SUN2 and lamin A. Furthermore, K8 loss in Caco-2 cells compromised nuclear membrane integrity basally and after shear stress. In conclusion, colonocyte K8 helps maintain nuclear envelope and lamina composition and contributes to nuclear integrity.
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Affiliation(s)
| | - Joel H. Nyström
- Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University
| | - Ciarán Butler-Hallissey
- Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University,Turku Bioscience Centre, University of Turku, and Åbo Akademi University, and,Aix Marseille Université, CNRS, INP UMR7051, NeuroCyto, 13005 Marseille, France
| | - Theresia Jansson
- Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University
| | - Taina R. H. Heikkilä
- Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University
| | | | - Roland Foisner
- Max Perutz Labs, Medical University of Vienna, Vienna Biocenter Campus, 1030 Vienna, Austria
| | | | - Karen M. Ridge
- Department of Cell and Developmental Biology and,Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Diana M. Toivola
- Cell Biology, Biosciences, Faculty of Science and Engineering, Åbo Akademi University,InFLAMES Research Flagship Center, Åbo Akademi University, 20500 Turku, Finland,Turku Center for Disease Modeling, University of Turku, 20520 Turku, Finland,*Address correspondence to: Diana M. Toivola ()
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11
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Ueda N, Maekawa M, Matsui TS, Deguchi S, Takata T, Katahira J, Higashiyama S, Hieda M. Inner Nuclear Membrane Protein, SUN1, is Required for Cytoskeletal Force Generation and Focal Adhesion Maturation. Front Cell Dev Biol 2022; 10:885859. [PMID: 35663386 PMCID: PMC9157646 DOI: 10.3389/fcell.2022.885859] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/02/2022] [Indexed: 12/20/2022] Open
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex is composed of the inner nuclear membrane-spanning SUN proteins and the outer nuclear membrane-spanning nesprin proteins. The LINC complex physically connects the nucleus and plasma membrane via the actin cytoskeleton to perform diverse functions including mechanotransduction from the extracellular environment to the nucleus. Mammalian somatic cells express two principal SUN proteins, namely SUN1 and SUN2. We have previously reported that SUN1, but not SUN2, is essential for directional cell migration; however, the underlying mechanism remains elusive. Because the balance between adhesive force and traction force is critical for cell migration, in the present study, we focused on focal adhesions (FAs) and the actin cytoskeleton. We observed that siRNA-mediated SUN1 depletion did not affect the recruitment of integrin β1, one of the ubiquitously expressed focal adhesion molecules, to the plasma membrane. Consistently, SUN1-depleted cells normally adhered to extracellular matrix proteins, including collagen, fibronectin, laminin, and vitronectin. In contrast, SUN1 depletion reduced the activation of integrin β1. Strikingly, the depletion of SUN1 interfered with the incorporation of vinculin into the focal adhesions, whereas no significant differences in the expression of vinculin were observed between wild-type and SUN1-depleted cells. In addition, SUN1 depletion suppressed the recruitment of zyxin to nascent focal adhesions. These data indicate that SUN1 is involved in the maturation of focal adhesions. Moreover, disruption of the SUN1-containing LINC complex abrogates the actin cytoskeleton and generation of intracellular traction force, despite the presence of SUN2. Thus, a physical link between the nucleus and cytoskeleton through SUN1 is required for the proper organization of actin, thereby suppressing the incorporation of vinculin and zyxin into focal adhesions and the activation of integrin β1, both of which are dependent on traction force. This study provides insights into a previously unappreciated signaling pathway from the nucleus to the cytoskeleton, which is in the opposite direction to the well-known mechanotransduction pathways from the extracellular matrix to the nucleus.
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Affiliation(s)
- Nanami Ueda
- Department of Medical Technology, Ehime Prefectural University of Health Sciences, Tobe, Japan
| | - Masashi Maekawa
- Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Matsuyama, Japan
- Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Japan
- Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | | | - Shinji Deguchi
- Division of Bioengineering, Osaka University, Toyonaka, Japan
| | - Tomoyo Takata
- Department of Medical Technology, Ehime Prefectural University of Health Sciences, Tobe, Japan
| | - Jun Katahira
- Department of Veterinary Sciences, Osaka Prefecture University, Sakai, Japan
| | - Shigeki Higashiyama
- Division of Cell Growth and Tumor Regulation, Proteo-Science Center (PROS), Ehime University, Matsuyama, Japan
- Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Japan
- Department of Oncogenesis and Growth Regulation, Osaka International Cancer Institute, Osaka, Japan
| | - Miki Hieda
- Department of Medical Technology, Ehime Prefectural University of Health Sciences, Tobe, Japan
- *Correspondence: Miki Hieda,
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12
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Nuclear lamin isoforms differentially contribute to LINC complex-dependent nucleocytoskeletal coupling and whole-cell mechanics. Proc Natl Acad Sci U S A 2022; 119:e2121816119. [PMID: 35439057 PMCID: PMC9170021 DOI: 10.1073/pnas.2121816119] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Interactions between the cell nucleus and cytoskeleton regulate cell mechanics and are facilitated by the interplay between the nuclear lamina and linker of nucleoskeleton and cytoskeleton (LINC) complexes. To date, the specific contribution of the four lamin isoforms to nucleocytoskeletal connectivity and whole-cell mechanics remains unknown. We discover that A- and B-type lamins distinctively interact with LINC complexes that bind F-actin and vimentin filaments to differentially modulate cortical stiffness, cytoplasmic stiffness, and contractility of mouse embryonic fibroblasts (MEFs). We propose and experimentally verify an integrated lamin–LINC complex–cytoskeleton model that explains cellular mechanical phenotypes in lamin-deficient MEFs. Our findings uncover potential mechanisms for cellular defects in human laminopathies and many cancers associated with mutations or modifications in lamin isoforms. The ability of a cell to regulate its mechanical properties is central to its function. Emerging evidence suggests that interactions between the cell nucleus and cytoskeleton influence cell mechanics through poorly understood mechanisms. Here we conduct quantitative confocal imaging to show that the loss of A-type lamins tends to increase nuclear and cellular volume while the loss of B-type lamins behaves in the opposite manner. We use fluorescence recovery after photobleaching, atomic force microscopy, optical tweezer microrheology, and traction force microscopy to demonstrate that A-type lamins engage with both F-actin and vimentin intermediate filaments (VIFs) through the linker of nucleoskeleton and cytoskeleton (LINC) complexes to modulate cortical and cytoplasmic stiffness as well as cellular contractility in mouse embryonic fibroblasts (MEFs). In contrast, we show that B-type lamins predominantly interact with VIFs through LINC complexes to regulate cytoplasmic stiffness and contractility. We then propose a physical model mediated by the lamin–LINC complex that explains these distinct mechanical phenotypes (mechanophenotypes). To verify this model, we use dominant negative constructs and RNA interference to disrupt the LINC complexes that facilitate the interaction of the nucleus with the F-actin and VIF cytoskeletons and show that the loss of these elements results in mechanophenotypes like those observed in MEFs that lack A- or B-type lamin isoforms. Finally, we demonstrate that the loss of each lamin isoform softens the cell nucleus and enhances constricted cell migration but in turn increases migration-induced DNA damage. Together, our findings uncover distinctive roles for each of the four major lamin isoforms in maintaining nucleocytoskeletal interactions and cellular mechanics.
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13
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Nuclear Dynamics and Chromatin Structure: Implications for Pancreatic Cancer. Cells 2021; 10:cells10102624. [PMID: 34685604 PMCID: PMC8534098 DOI: 10.3390/cells10102624] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/20/2021] [Accepted: 09/27/2021] [Indexed: 12/14/2022] Open
Abstract
Changes in nuclear shape have been extensively associated with the dynamics and functionality of cancer cells. In most normal cells, nuclei have a regular ellipsoid shape and minimal variation in nuclear size; however, an irregular nuclear contour and abnormal nuclear size is often observed in cancer, including pancreatic cancer. Furthermore, alterations in nuclear morphology have become the 'gold standard' for tumor staging and grading. Beyond the utility of altered nuclear morphology as a diagnostic tool in cancer, the implications of altered nuclear structure for the biology and behavior of cancer cells are profound as changes in nuclear morphology could impact cellular responses to physical strain, adaptation during migration, chromatin organization, and gene expression. Here, we aim to highlight and discuss the factors that regulate nuclear dynamics and their implications for pancreatic cancer biology.
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14
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Castañón MJ, Wiche G. Identifying Plectin Isoform Functions through Animal Models. Cells 2021; 10:cells10092453. [PMID: 34572100 PMCID: PMC8468861 DOI: 10.3390/cells10092453] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/04/2021] [Accepted: 09/14/2021] [Indexed: 12/12/2022] Open
Abstract
Plectin, a high-molecular-weight cytoskeletal linker protein, binds with high affinity to intermediate filaments of all types and connects them to junctional complexes, organelles, and inner membrane systems. In addition, it interacts with actomyosin structures and microtubules. As a multifunctional protein, plectin has been implicated in several multisystemic diseases, the most common of which is epidermolysis bullosa simplex with muscular dystrophy (EBS-MD). A great part of our knowledge about plectin’s functional diversity has been gained through the analysis of a unique collection of transgenic mice that includes a full (null) knockout (KO), several tissue-restricted and isoform-specific KOs, three double KOs, and two knock-in lines. The key molecular features and pathological phenotypes of these mice will be discussed in this review. In summary, the analysis of the different genetic models indicated that a functional plectin is required for the proper function of striated and simple epithelia, cardiac and skeletal muscle, the neuromuscular junction, and the vascular endothelium, recapitulating the symptoms of humans carrying plectin mutations. The plectin-null line showed severe skin and muscle phenotypes reflecting the importance of plectin for hemidesmosome and sarcomere integrity; whereas the ablation of individual isoforms caused a specific phenotype in myofibers, basal keratinocytes, or neurons. Tissue-restricted ablation of plectin rendered the targeted cells less resilient to mechanical stress. Studies based on animal models other than the mouse, such as zebrafish and C. elegans, will be discussed as well.
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15
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van Ingen MJA, Kirby TJ. LINCing Nuclear Mechanobiology With Skeletal Muscle Mass and Function. Front Cell Dev Biol 2021; 9:690577. [PMID: 34368139 PMCID: PMC8335485 DOI: 10.3389/fcell.2021.690577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 06/25/2021] [Indexed: 11/13/2022] Open
Abstract
Skeletal muscle demonstrates a high degree of adaptability in response to changes in mechanical input. The phenotypic transformation in response to mechanical cues includes changes in muscle mass and force generating capabilities, yet the molecular pathways that govern skeletal muscle adaptation are still incompletely understood. While there is strong evidence that mechanotransduction pathways that stimulate protein synthesis play a key role in regulation of muscle mass, there are likely additional mechano-sensitive mechanisms important for controlling functional muscle adaptation. There is emerging evidence that the cell nucleus can directly respond to mechanical signals (i.e., nuclear mechanotransduction), providing a potential additional level of cellular regulation for controlling skeletal muscle mass. The importance of nuclear mechanotransduction in cellular function is evident by the various genetic diseases that arise from mutations in proteins crucial to the transmission of force between the cytoskeleton and the nucleus. Intriguingly, these diseases preferentially affect cardiac and skeletal muscle, suggesting that nuclear mechanotransduction is critically important for striated muscle homeostasis. Here we discuss our current understanding for how the nucleus acts as a mechanosensor, describe the main cytoskeletal and nuclear proteins involved in the process, and propose how similar mechanoresponsive mechanisms could occur in the unique cellular environment of a myofiber. In addition, we examine how nuclear mechanotransduction fits into our current framework for how mechanical stimuli regulates skeletal muscle mass.
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Affiliation(s)
- Maria J A van Ingen
- Biomolecular Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Tyler J Kirby
- Department of Physiology, Amsterdam Cardiovascular Sciences, Amsterdam Movement Sciences, Amsterdam UMC, Amsterdam, Netherlands
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16
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Zhang Y, Yang L, Huang L, Liu G, Nie X, Zhang X, Xing X. SUN5 Interacting With Nesprin3 Plays an Essential Role in Sperm Head-to-Tail Linkage: Research on Sun5 Gene Knockout Mice. Front Cell Dev Biol 2021; 9:684826. [PMID: 34268309 PMCID: PMC8276135 DOI: 10.3389/fcell.2021.684826] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/11/2021] [Indexed: 12/24/2022] Open
Abstract
Acephalic spermatozoa syndrome is a rare genetic and reproductive disease. Recent studies have shown that approximately 33–47% of patients with acephalic spermatozoa syndrome have SUN5 mutations, but the molecular mechanism underlying this phenomenon has not been elucidated. In this study, we generated Sun5 knockout mice and found that the head-to-tail linkage was broken in Sun5–/– mice, which was similar to human acephalic spermatozoa syndrome. Furthermore, ultrastructural imaging revealed that the head-tail coupling apparatus (HTCA) and the centrosome were distant from the nucleus at steps 9–10 during spermatid elongation. With the manchette disappearing at steps 13–14, the head and the tail segregated. To explore the molecular mechanism underlying this process, bioinformatic analysis was performed and showed that Sun5 may interact with Nesprin3. Further coimmunoprecipitation (Co-IP) and immunofluorescence assays confirmed that Sun5 and Nesprin3 were indeed bona fide interaction partners that formed the linker of the nucleoskeleton and cytoskeleton (LINC) complex participating in the connection of the head and tail of spermatozoa. Nesprin3 was located posterior and anterior to the nucleus during spermiogenesis in wild-type mice, whereas it lost its localization at the implantation fossa of the posterior region in Sun5–/– mice. Without correct localization of Nesprin3 at the nuclear membrane, the centrosome, which is the originator of the flagellum, was distant from the nucleus, which led to the separation of the head and tail. In addition, isobaric tag for relative and absolute quantitation results showed that 47 proteins were upregulated, and 56 proteins were downregulated, in the testis in Sun5–/– mice, and the downregulation of spermatogenesis-related proteins (Odf1 and Odf2) may also contribute to the damage to the spermatozoa head-to-tail linkage. Our findings suggested that Sun5 is essential for the localization of Nesprin3 at the posterior nuclear membrane, which plays an essential role in the sperm head-tail connection.
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Affiliation(s)
- Yunfei Zhang
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China.,Department of Laboratory Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Linfei Yang
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Lihua Huang
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Gang Liu
- The Institute of Reproduction and Stem Cell Engineering, Central South University, Changsha, China
| | - Xinmin Nie
- Department of Laboratory Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Xinxing Zhang
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China.,Department of Laboratory Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Xiaowei Xing
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
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17
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Jahed Z, Domkam N, Ornowski J, Yerima G, Mofrad MRK. Molecular models of LINC complex assembly at the nuclear envelope. J Cell Sci 2021; 134:269219. [PMID: 34152389 DOI: 10.1242/jcs.258194] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Large protein complexes assemble at the nuclear envelope to transmit mechanical signals between the cytoskeleton and nucleoskeleton. These protein complexes are known as the linkers of the nucleoskeleton and cytoskeleton complexes (LINC complexes) and are formed by the interaction of SUN and KASH domain proteins in the nuclear envelope. Ample evidence suggests that SUN-KASH complexes form higher-order assemblies to withstand and transfer forces across the nuclear envelope. Herein, we present a review of recent studies over the past few years that have shed light on the mechanisms of SUN-KASH interactions, their higher order assembly, and the molecular mechanisms of force transfer across these complexes.
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Affiliation(s)
- Zeinab Jahed
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA.,Department of Nanoengineering, Jacobs School of Engineering, University of California, San Diego, CA 92039, USA
| | - Nya Domkam
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Jessica Ornowski
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Ghafar Yerima
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Mohammad R K Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA.,Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
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18
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Li YL, Cheng XN, Lu T, Shao M, Shi DL. Syne2b/Nesprin-2 Is Required for Actin Organization and Epithelial Integrity During Epiboly Movement in Zebrafish. Front Cell Dev Biol 2021; 9:671887. [PMID: 34222245 PMCID: PMC8248263 DOI: 10.3389/fcell.2021.671887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 05/28/2021] [Indexed: 11/25/2022] Open
Abstract
Syne2b/nesprin-2 is a giant protein implicated in tethering the nucleus to the cytoskeleton and plays an important role in maintaining cellular architecture. Epiboly is a conserved morphogenetic movement that involves extensive spreading and thinning of the epithelial blastoderm to shape the embryo and organize the three germ layers. Dynamic cytoskeletal organization is critical for this process, but how it is regulated remains elusive. Here we generated a zebrafish syne2b mutant line and analyzed the effects of impaired Syne2b function during early development. By CRISPR/Cas9-mediated genome editing, we obtained a large deletion in the syne2b locus, predicted to cause truncation of the nuclear localization KASH domain in the translated protein. Maternal and zygotic syne2b embryos showed delayed epiboly initiation and progression without defects in embryonic patterning. Remarkably, disruption of Syne2b function severely impaired cytoskeletal organization across the embryo, leading to aberrant clustering of F-actin at multiple cell contact regions and abnormal cell shape changes. These caused disintegration of the epithelial blastoderm before the end of gastrulation in most severely affected embryos. Moreover, the migration of yolk nuclear syncytium also became defective, likely due to disorganized cytoskeletal networks at the blastoderm margin and in the yolk cell. These findings demonstrate an essential function of Syne2b in maintaining cytoskeletal architecture and epithelial integrity during epiboly movement.
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Affiliation(s)
- Yu-Long Li
- School of Life Sciences, Shandong University, Qingdao, China
| | | | - Tong Lu
- School of Life Sciences, Shandong University, Qingdao, China
| | - Ming Shao
- School of Life Sciences, Shandong University, Qingdao, China
| | - De-Li Shi
- Affiliated Hospital of Guangdong Medical University, Zhanjiang, China.,Laboratory of Developmental Biology, CNRS-UMR 7622, Institut de Biologie Paris-Seine (IBPS), Sorbonne University, Paris, France
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19
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The SUN2-nesprin-2 LINC complex and KIF20A function in the Golgi dispersal. Sci Rep 2021; 11:5358. [PMID: 33686165 PMCID: PMC7940470 DOI: 10.1038/s41598-021-84750-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 02/12/2021] [Indexed: 01/31/2023] Open
Abstract
The morphology of the Golgi complex is influenced by the cellular context, which strictly correlates with nuclear functions; however, the mechanism underlying this association remains elusive. The inner nuclear membrane SUN proteins, SUN1 and SUN2, have diverse functions together with the outer nuclear membrane nesprin proteins, which comprise the LINC complex. We found that depletion of SUN1 leads to Golgi complex dispersion with maintenance of ministacks and retained function for vesicle transport through the Golgi complex. In addition, SUN2 associates with microtubule plus-end-directed motor KIF20A, possibly via nesprin-2. KIF20A plays a role in the Golgi dispersion in conjunction with the SUN2-nesprin-2 LINC complex in SUN1-depleted cells, suggesting that SUN1 suppresses the function of the SUN2-nesprin-2 LINC complex under a steady-state condition. Further, SUN1-knockout mice, which show impaired cerebellar development and cerebellar ataxia, presented altered Golgi morphology in Purkinje cells. These findings revealed a regulation of the Golgi organization by the LINC complex.
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20
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Jabre S, Hleihel W, Coirault C. Nuclear Mechanotransduction in Skeletal Muscle. Cells 2021; 10:cells10020318. [PMID: 33557157 PMCID: PMC7913907 DOI: 10.3390/cells10020318] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/11/2022] Open
Abstract
Skeletal muscle is composed of multinucleated, mature muscle cells (myofibers) responsible for contraction, and a resident pool of mononucleated muscle cell precursors (MCPs), that are maintained in a quiescent state in homeostatic conditions. Skeletal muscle is remarkable in its ability to adapt to mechanical constraints, a property referred as muscle plasticity and mediated by both MCPs and myofibers. An emerging body of literature supports the notion that muscle plasticity is critically dependent upon nuclear mechanotransduction, which is transduction of exterior physical forces into the nucleus to generate a biological response. Mechanical loading induces nuclear deformation, changes in the nuclear lamina organization, chromatin condensation state, and cell signaling, which ultimately impacts myogenic cell fate decisions. This review summarizes contemporary insights into the mechanisms underlying nuclear force transmission in MCPs and myofibers. We discuss how the cytoskeleton and nuclear reorganizations during myogenic differentiation may affect force transmission and nuclear mechanotransduction. We also discuss how to apply these findings in the context of muscular disorders. Finally, we highlight current gaps in knowledge and opportunities for further research in the field.
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Affiliation(s)
- Saline Jabre
- Sorbonne Université, INSERM UMRS-974 and Institut de Myologie, 75013 Paris, France;
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kasik (USEK), Jounieh 446, Lebanon;
| | - Walid Hleihel
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kasik (USEK), Jounieh 446, Lebanon;
- Department of Basic Health Sciences, Faculty of Medicine, Holy Spirit University of Kaslik (USEK), Jounieh 446, Lebanon
| | - Catherine Coirault
- Sorbonne Université, INSERM UMRS-974 and Institut de Myologie, 75013 Paris, France;
- Correspondence:
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21
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Kozono T, Sato H, Okumura W, Jogano C, Tamura-Nakano M, Kawamura YI, Rohrer J, Tonozuka T, Nishikawa A. The N-terminal region of Jaw1 has a role to inhibit the formation of organized smooth endoplasmic reticulum as an intrinsically disordered region. Sci Rep 2021; 11:753. [PMID: 33436890 PMCID: PMC7804115 DOI: 10.1038/s41598-020-80258-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 12/18/2020] [Indexed: 02/07/2023] Open
Abstract
Jaw1/LRMP is a type II integral membrane protein that is localized at the endoplasmic reticulum (ER) and outer nuclear membrane. We previously reported that a function of Jaw1 is to maintain the nuclear shape as a KASH protein via its carboxyl terminal region, a component of linker of nucleoskeleton and cytoskeleton complex in the oligomeric state. Although the oligomerization of some KASH proteins via the cytosolic regions serves to stabilize protein-protein interactions, the issue of how the oligomerization of Jaw1 is regulated is not completely understood. Therefore, we focused on three distinct regions on the cytosolic face of Jaw1: the N-terminal region, the coiled-coil domain and the stem region, in terms of oligomerization. A co-immunoprecipitation assay showed that its coiled-coil domain is a candidate for the oligomerization site. Furthermore, our data indicated that the N-terminal region prevents the aberrant oligomerization of Jaw1 as an intrinsically disordered region (IDR). Importantly, the ectopic expression of an N-terminal region deleted mutant caused the formation of organized smooth ER (OSER), structures such as nuclear karmellae and whorls, in B16F10 cells. Furthermore, this OSER interfered with the localization of the oligomer and interactors such as the type III inositol 1,4,5-triphosphate receptor (IP3R3) and SUN2. In summary, the N-terminal region of Jaw1 inhibits the formation of OSER as an IDR to maintain the homeostatic localization of interactors on the ER membrane.
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Affiliation(s)
- Takuma Kozono
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan.,Department of Gastroenterology, The Research Center for Hepatitis and Immunology, Research Institute, National Center for Global Health and Medicine, Chiba, 272-8516, Japan
| | - Hiroyuki Sato
- Department of Applied Biological Chemistry, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan
| | - Wataru Okumura
- Department of Food and Energy Systems Science, Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, 184-8588, Japan
| | - Chifuyu Jogano
- Department of Applied Biological Chemistry, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan
| | - Miwa Tamura-Nakano
- Communal Laboratory, Research Institute, National Center for Global Health and Medicine, Tokyo, 162-8655, Japan
| | - Yuki I Kawamura
- Department of Gastroenterology, The Research Center for Hepatitis and Immunology, Research Institute, National Center for Global Health and Medicine, Chiba, 272-8516, Japan
| | - Jack Rohrer
- Institute of Chemistry and Biotechnology, Zurich University of Applied Sciences, CH-8820, Waedenswil, Switzerland
| | - Takashi Tonozuka
- Department of Applied Biological Chemistry, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan
| | - Atsushi Nishikawa
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan. .,Department of Applied Biological Chemistry, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan. .,Department of Food and Energy Systems Science, Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, 184-8588, Japan.
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22
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Jo J, Abdi Nansa S, Kim DH. Molecular Regulators of Cellular Mechanoadaptation at Cell-Material Interfaces. Front Bioeng Biotechnol 2020; 8:608569. [PMID: 33364232 PMCID: PMC7753015 DOI: 10.3389/fbioe.2020.608569] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/18/2020] [Indexed: 12/19/2022] Open
Abstract
Diverse essential cellular behaviors are determined by extracellular physical cues that are detected by highly orchestrated subcellular interactions with the extracellular microenvironment. To maintain the reciprocity of cellular responses and mechanical properties of the extracellular matrix, cells utilize a variety of signaling pathways that transduce biophysical stimuli to biochemical reactions. Recent advances in the micromanipulation of individual cells have shown that cellular responses to distinct physical and chemical features of the material are fundamental determinants of cellular mechanosensation and mechanotransduction. In the process of outside-in signal transduction, transmembrane protein integrins facilitate the formation of focal adhesion protein clusters that are connected to the cytoskeletal architecture and anchor the cell to the substrate. The linkers of nucleoskeleton and cytoskeleton molecular complexes, collectively termed LINC, are critical signal transducers that relay biophysical signals between the extranuclear cytoplasmic region and intranuclear nucleoplasmic region. Mechanical signals that involve cytoskeletal remodeling ultimately propagate into the nuclear envelope comprising the nuclear lamina in assistance with various nuclear membrane proteins, where nuclear mechanics play a key role in the subsequent alteration of gene expression and epigenetic modification. These intracellular mechanical signaling cues adjust cellular behaviors directly associated with mechanohomeostasis. Diverse strategies to modulate cell-material interfaces, including alteration of surface rigidity, confinement of cell adhesive region, and changes in surface topology, have been proposed to identify cellular signal transduction at the cellular and subcellular levels. In this review, we will discuss how a diversity of alterations in the physical properties of materials induce distinct cellular responses such as adhesion, migration, proliferation, differentiation, and chromosomal organization. Furthermore, the pathological relevance of misregulated cellular mechanosensation and mechanotransduction in the progression of devastating human diseases, including cardiovascular diseases, cancer, and aging, will be extensively reviewed. Understanding cellular responses to various extracellular forces is expected to provide new insights into how cellular mechanoadaptation is modulated by manipulating the mechanics of extracellular matrix and the application of these materials in clinical aspects.
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Affiliation(s)
| | | | - Dong-Hwee Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, South Korea
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23
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Kmonickova V, Frolikova M, Steger K, Komrskova K. The Role of the LINC Complex in Sperm Development and Function. Int J Mol Sci 2020; 21:E9058. [PMID: 33260574 PMCID: PMC7730847 DOI: 10.3390/ijms21239058] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 11/24/2020] [Accepted: 11/26/2020] [Indexed: 11/23/2022] Open
Abstract
The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men. The present review provides a comprehensive overview on our current knowledge of LINC complex subtypes present in germ cells and its central role for male reproduction. Future studies on distinct LINC complex components are an absolute requirement to improve the diagnosis of idiopathic male factor infertility and the outcome of assisted reproduction.
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Affiliation(s)
- Vera Kmonickova
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic; (V.K.); (M.F.)
| | - Michaela Frolikova
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic; (V.K.); (M.F.)
| | - Klaus Steger
- Department of Urology, Pediatric Urology and Andrology, Molecular Andrology, Justus-Liebig University, 35392 Giessen, Germany;
| | - Katerina Komrskova
- Laboratory of Reproductive Biology, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Prumyslova 595, 252 50 Vestec, Czech Republic; (V.K.); (M.F.)
- Department of Zoology, Faculty of Science, Charles University, Vinicna 7, 128 44 Prague 2, Czech Republic
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Heffler J, Shah PP, Robison P, Phyo S, Veliz K, Uchida K, Bogush A, Rhoades J, Jain R, Prosser BL. A Balance Between Intermediate Filaments and Microtubules Maintains Nuclear Architecture in the Cardiomyocyte. Circ Res 2019; 126:e10-e26. [PMID: 31822208 DOI: 10.1161/circresaha.119.315582] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Rationale: Mechanical forces are transduced to nuclear responses via the linkers of the nucleoskeleton and cytoskeleton (LINC) complex, which couples the cytoskeleton to the nuclear lamina and associated chromatin. While disruption of the LINC complex can cause cardiomyopathy, the relevant interactions that bridge the nucleoskeleton to cytoskeleton are poorly understood in the cardiomyocyte, where cytoskeletal organization is unique. Furthermore, while microtubules and desmin intermediate filaments associate closely with cardiomyocyte nuclei, the importance of these interactions is unknown. Objective: Here, we sought to determine how cytoskeletal interactions with the LINC complex regulate nuclear homeostasis in the cardiomyocyte. Methods and Results: To this end, we acutely disrupted the LINC complex, microtubules, actin, and intermediate filaments and assessed the consequences on nuclear morphology and genome organization in rat ventricular cardiomyocytes via a combination of super-resolution imaging, biophysical, and genomic approaches. We find that a balance of dynamic microtubules and desmin intermediate filaments is required to maintain nuclear shape and the fidelity of the nuclear envelope and lamina. Upon depletion of desmin (or nesprin [nuclear envelope spectrin repeat protein]-3, its binding partner in the LINC complex), polymerizing microtubules collapse the nucleus and drive infolding of the nuclear membrane. This results in DNA damage, a loss of genome organization, and broad transcriptional changes. The collapse in nuclear integrity is concomitant with compromised contractile function and may contribute to the pathophysiological changes observed in desmin-related myopathies. Conclusions: Disrupting the tethering of desmin to the nucleus results in a loss of nuclear homeostasis and rapid alterations to cardiomyocyte function. Our data suggest that a balance of forces imposed by intermediate filaments and microtubules is required to maintain nuclear structure and genome organization in the cardiomyocyte.
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Affiliation(s)
- Julie Heffler
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Parisha P Shah
- Department of Medicine, Cardiovascular Institute, Institute of Regenerative Medicine, and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine (P.P.S., J.R., R.J.)
| | - Patrick Robison
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Sai Phyo
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Kimberly Veliz
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Keita Uchida
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Alexey Bogush
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
| | - Joshua Rhoades
- Department of Medicine, Cardiovascular Institute, Institute of Regenerative Medicine, and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine (P.P.S., J.R., R.J.)
- Institute for Biomedical Informatics, University of Pennsylvania, Philadelphia (J.R.)
| | - Rajan Jain
- Department of Medicine, Cardiovascular Institute, Institute of Regenerative Medicine, and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine (P.P.S., J.R., R.J.)
| | - Benjamin L Prosser
- From the Department of Physiology, Pennsylvania Muscle Institute, Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine (J.H., P.R., S.P., K.V., K.U., A.B., B.L.P.)
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Sneider A, Hah J, Wirtz D, Kim DH. Recapitulation of molecular regulators of nuclear motion during cell migration. Cell Adh Migr 2019; 13:50-62. [PMID: 30261154 PMCID: PMC6527386 DOI: 10.1080/19336918.2018.1506654] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 07/05/2018] [Accepted: 07/18/2018] [Indexed: 01/12/2023] Open
Abstract
Cell migration is a highly orchestrated cellular event that involves physical interactions of diverse subcellular components. The nucleus as the largest and stiffest organelle in the cell not only maintains genetic functionality, but also actively changes its morphology and translocates through dynamic formation of nucleus-bound contractile stress fibers. Nuclear motion is an active and essential process for successful cell migration and nucleus self-repairs in response to compression and extension forces in complex cell microenvironment. This review recapitulates molecular regulators that are crucial for nuclear motility during cell migration and highlights recent advances in nuclear deformation-mediated rupture and repair processes in a migrating cell.
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Affiliation(s)
- Alexandra Sneider
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Jungwon Hah
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea
| | - Denis Wirtz
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Dong-Hwee Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea
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26
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A Glance at the Nuclear Envelope Spectrin Repeat Protein 3. BIOMED RESEARCH INTERNATIONAL 2019; 2019:1651805. [PMID: 31828088 PMCID: PMC6886330 DOI: 10.1155/2019/1651805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/14/2019] [Indexed: 12/27/2022]
Abstract
Nuclear envelope spectrin repeat protein 3 (nesprin-3) is an evolutionarily-conserved structural protein, widely-expressed in vertebrate cells. Along with other nesprin family members, nesprin-3 acts as an essential component of the linker of nucleoskeleton and cytoskeleton (LINC) complex. Naturally, nesprin-3 shares many functions with LINC, including the localization of various cellular structures and bridging of the nucleoskeleton and cytoskeleton, observed in vitro. When nesprin-3 was knocked down in vivo, using zebrafish and mouse models, however, the animals were minimally affected. This paradoxical observation should not limit the physiological importance of nesprin-3, as recently, nesprin-3 has reignited the interest of the research community in studies on cancer cells migration. Moreover, nesprin-3 also plays an active role in certain developmental conditions such as adipogenesis and spermatogenesis, although more studies are needed. Meanwhile, the various protein binding partners of nesprin-3 should also be emphasized, as they are necessary for maintaining the structure of nesprin-3 and enabling it to carry out its various physiological and pathological functions. Nesprin-3 promises to further our understanding of these complex cellular events. Therefore, this review will focus on nesprin-3, examining it from a genetic, structural, and functional perspective. The final part of the review will in turn address the limitations of existing research and the future perspectives for the study of nesprin-3.
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Janin A, Gache V. Nesprins and Lamins in Health and Diseases of Cardiac and Skeletal Muscles. Front Physiol 2018; 9:1277. [PMID: 30245638 PMCID: PMC6137955 DOI: 10.3389/fphys.2018.01277] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/22/2018] [Indexed: 12/26/2022] Open
Abstract
Since the discovery of the inner nuclear transmembrane protein emerin in the early 1990s, nuclear envelope (NE) components and related involvement in nuclei integrity and functionality have been highly investigated. The NE is composed of two distinct lipid bilayers described as the inner (INM) and outer (ONM) nuclear membrane. NE proteins can be specifically “integrated” in the INM (such as emerin and SUN proteins) or in the ONM such as nesprins. Additionally, flanked to the INM, the nuclear lamina, a proteinaceous meshwork mainly composed of lamins A and C completes NE composition. This network of proteins physically interplays to guarantee NE integrity and most importantly, shape the bridge between cytoplasmic cytoskeletons networks (such as microtubules and actin) and the genome, through the anchorage to the heterochromatin. The essential network driving the connection of nucleoskeleton with cytoskeleton takes place in the perinuclear space (the space between ONM and INM) with the contribution of the LINC complex (for Linker of Nucleoskeleton to Cytoskeleton), hosting KASH and SUN proteins interactions. This close interplay between compartments has been related to diverse functions from nuclear integrity, activity and positioning through mechanotransduction pathways. At the same time, mutations in NE components genes coding for proteins such as lamins or nesprins, had been associated with a wide range of congenital diseases including cardiac and muscular diseases. Although most of these NE associated proteins are ubiquitously expressed, a large number of tissue-specific disorders have been associated with diverse pathogenic mutations. Thus, diagnosis and molecular explanation of this group of diseases, commonly called “nuclear envelopathies,” is currently challenging. This review aims, first, to give a better understanding of diverse functions of the LINC complex components, from the point of view of lamins and nesprins. Second, to summarize human congenital diseases with a special focus on muscle and heart abnormalities, caused by mutations in genes coding for these two types of NE associated proteins.
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Affiliation(s)
- Alexandre Janin
- CNRS UMR5310, INSERM U1217, Institut NeuroMyoGène, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France.,Laboratoire de Cardiogénétique Moléculaire, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Bron, France
| | - Vincent Gache
- CNRS UMR5310, INSERM U1217, Institut NeuroMyoGène, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
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Abstract
Pancreatic cancer is an aggressive and intractable malignancy with high mortality. This is due in part to a high resistance to chemotherapeutics and radiation treatment conferred by diverse regulatory mechanisms. Among these, constituents of the nuclear envelope play a significant role in regulating oncogenesis and pancreatic tumor biology, and this review focuses on three specific components and their roles in cancer. The LINC complex is a nuclear envelope component formed by proteins with SUN and KASH domains that interact in the periplasmic space of the nuclear envelope. These interactions functionally and structurally couple the cytoskeleton to chromatin and facilitates gene regulation informed by cytoplasmic activity. Furthermore, cancer cell invasiveness is impacted by LINC complex biology. The nuclear lamina is adjacent to the inner nuclear membrane of the nuclear envelope and can actively regulate chromatin in addition to providing structural integrity to the nucleus. A disrupted lamina can impart biophysical compromise to nuclear structure and function, as well as form dysfunctional micronuclei that may lead to genomic instability and chromothripsis. In close relationship to the nuclear lamina is the nuclear pore complex, a large megadalton structure that spans both outer and inner membranes of the nuclear envelope. The nuclear pore complex mediates bidirectional nucleocytoplasmic transport and is comprised of specialized proteins called nucleoporins that are overexpressed in many cancers and are diagnostic markers for oncogenesis. Furthermore, recent demonstration of gene regulatory functions for discrete nucleoporins independent of their nuclear trafficking function suggests that these proteins may contribute more to malignant phenotypes beyond serving as biomarkers. The nuclear envelope is thus a complex, intricate regulator of cell signaling, with roles in pancreatic tumorigenesis and general oncogenic transformation.
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Affiliation(s)
| | - Randolph S. Faustino
- Genetics and Genomics, Sanford Research, Sioux Falls, SD 57104, USA
- Department of Pediatrics, Sanford School of Medicine of the University of South Dakota, Sioux Falls, SD 57105, USA
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Kozono T, Tadahira K, Okumura W, Itai N, Tamura-Nakano M, Dohi T, Tonozuka T, Nishikawa A. Jaw1/LRMP has a role in maintaining nuclear shape via interaction with SUN proteins. J Biochem 2018; 164:303-311. [DOI: 10.1093/jb/mvy053] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 05/28/2018] [Indexed: 12/31/2022] Open
Affiliation(s)
- Takuma Kozono
- Department of Food and Energy Systems Science, Graduate School of Bio-Applications Systems Engineering, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
| | - Kazuko Tadahira
- Division of Applied Biological Chemistry, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
| | - Wataru Okumura
- Department of Food and Energy Systems Science, Graduate School of Bio-Applications Systems Engineering, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
| | - Nao Itai
- Division of Applied Biological Chemistry, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
| | - Miwa Tamura-Nakano
- Communal Laboratory, Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, Japan
| | - Taeko Dohi
- Department of Gastroenterology, Research Center for Hepatitis and Immunology, Research Institute, National Center for Global Health and Medicine, 1-7-1 Kohnodai, Ichikawa, Chiba, Japan
| | - Takashi Tonozuka
- Division of Applied Biological Chemistry, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
| | - Atsushi Nishikawa
- Department of Food and Energy Systems Science, Graduate School of Bio-Applications Systems Engineering, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
- Division of Applied Biological Chemistry, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, Japan
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30
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Linker of nucleoskeleton and cytoskeleton complex proteins in cardiomyopathy. Biophys Rev 2018; 10:1033-1051. [PMID: 29869195 PMCID: PMC6082319 DOI: 10.1007/s12551-018-0431-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 05/24/2018] [Indexed: 12/21/2022] Open
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex couples the nuclear lamina to the cytoskeleton. The LINC complex and its associated proteins play diverse roles in cells, ranging from genome organization, nuclear morphology, gene expression, to mechanical stability. The importance of a functional LINC complex is highlighted by the large number of mutations in genes encoding LINC complex proteins that lead to skeletal and cardiac myopathies. In this review, the structure, function, and interactions between components of the LINC complex will be described. Mutations that are known to cause cardiomyopathy in patients will be discussed alongside their respective mouse models. Furthermore, future challenges for the field and emerging technologies to investigate LINC complex function will be discussed.
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31
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May CK, Carroll CW. Differential incorporation of SUN-domain proteins into LINC complexes is coupled to gene expression. PLoS One 2018; 13:e0197621. [PMID: 29813079 PMCID: PMC5973619 DOI: 10.1371/journal.pone.0197621] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 05/05/2018] [Indexed: 11/19/2022] Open
Abstract
LInkers of Nucleoskeleton and Cytoskeleton (LINC) complexes, composed of SUN and KASH-domain proteins, span the nuclear envelope and physically connect the nuclear interior to cytoskeletal elements. Most human cells contain two SUN proteins, Sun1 and Sun2, and several KASH-proteins suggesting that multiple functionally distinct LINC complexes co-exist in the nuclear envelope. We show here, however, that while Sun1 and Sun2 in HeLa cells are each able to bind KASH-domains, Sun1 is more efficiently incorporated into LINC complexes under normal growth conditions. Furthermore, the balance of Sun1 and Sun2 incorporated into LINC complexes is cell type-specific and is correlated with SRF/Mkl1-dependent gene expression. In addition, we found that Sun1 has a LINC complex-independent role in transcriptional control, possibly by regulating the SRF/Mkl1 pathway. Together, these data reveal novel insights into the mechanisms of LINC complex regulation and demonstrate that Sun1 modulates gene expression independently of its incorporation into LINC complexes.
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Affiliation(s)
- Christopher K. May
- Dept. Of Cell Biology, Yale School of Medicine, New Haven, CT, United States of America
| | - Christopher W. Carroll
- Dept. Of Cell Biology, Yale School of Medicine, New Haven, CT, United States of America
- * E-mail:
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32
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Mouse models of nesprin-related diseases. Biochem Soc Trans 2018; 46:669-681. [PMID: 29784648 DOI: 10.1042/bst20180085] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/05/2018] [Accepted: 04/20/2018] [Indexed: 02/05/2023]
Abstract
Nesprins (nuclear envelope spectrin repeat proteins) are a family of multi-isomeric scaffolding proteins. Nesprins form the LInker of Nucleoskeleton-and-Cytoskeleton (LINC) complex with SUN (Sad1p/UNC84) domain-containing proteins at the nuclear envelope, in association with lamin A/C and emerin, linking the nucleoskeleton to the cytoskeleton. The LINC complex serves as both a physical linker between the nuclear lamina and the cytoskeleton and a mechanosensor. The LINC complex has a broad range of functions and is involved in maintaining nuclear architecture, nuclear positioning and migration, and also modulating gene expression. Over 80 disease-related variants have been identified in SYNE-1/2 (nesprin-1/2) genes, which result in muscular or central nervous system disorders including autosomal dominant Emery-Dreifuss muscular dystrophy, dilated cardiomyopathy and autosomal recessive cerebellar ataxia type 1. To date, 17 different nesprin mouse lines have been established to mimic these nesprin-related human diseases, which have provided valuable insights into the roles of nesprin and its scaffold LINC complex in a tissue-specific manner. In this review, we summarise the existing nesprin mouse models, compare their phenotypes and discuss the potential mechanisms underlying nesprin-associated diseases.
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Szczesny SE, Mauck RL. The Nuclear Option: Evidence Implicating the Cell Nucleus in Mechanotransduction. J Biomech Eng 2017; 139:2592356. [PMID: 27918797 DOI: 10.1115/1.4035350] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Indexed: 02/06/2023]
Abstract
Biophysical stimuli presented to cells via microenvironmental properties (e.g., alignment and stiffness) or external forces have a significant impact on cell function and behavior. Recently, the cell nucleus has been identified as a mechanosensitive organelle that contributes to the perception and response to mechanical stimuli. However, the specific mechanotransduction mechanisms that mediate these effects have not been clearly established. Here, we offer a comprehensive review of the evidence supporting (and refuting) three hypothetical nuclear mechanotransduction mechanisms: physical reorganization of chromatin, signaling at the nuclear envelope, and altered cytoskeletal structure/tension due to nuclear remodeling. Our goal is to provide a reference detailing the progress that has been made and the areas that still require investigation regarding the role of nuclear mechanotransduction in cell biology. Additionally, we will briefly discuss the role that mathematical models of cell mechanics can play in testing these hypotheses and in elucidating how biophysical stimulation of the nucleus drives changes in cell behavior. While force-induced alterations in signaling pathways involving lamina-associated polypeptides (LAPs) (e.g., emerin and histone deacetylase 3 (HDAC3)) and transcription factors (TFs) located at the nuclear envelope currently appear to be the most clearly supported mechanism of nuclear mechanotransduction, additional work is required to examine this process in detail and to more fully test alternative mechanisms. The combination of sophisticated experimental techniques and advanced mathematical models is necessary to enhance our understanding of the role of the nucleus in the mechanotransduction processes driving numerous critical cell functions.
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Affiliation(s)
- Spencer E Szczesny
- Department of Orthopaedic Surgery, University of Pennsylvania, 424 Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, PA 19104; Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, 3900 Woodland Avenue, Philadelphia, PA 19104
| | - Robert L Mauck
- Department of Orthopaedic Surgery, University of Pennsylvania, 424 Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, PA 19104; Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz Veterans Affairs Medical Center, 3900 Woodland Avenue, Philadelphia, PA 19104;Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd Street, Philadelphia, PA 19104 e-mail:
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34
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Sanghvi-Shah R, Weber GF. Intermediate Filaments at the Junction of Mechanotransduction, Migration, and Development. Front Cell Dev Biol 2017; 5:81. [PMID: 28959689 PMCID: PMC5603733 DOI: 10.3389/fcell.2017.00081] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/30/2017] [Indexed: 01/04/2023] Open
Abstract
Mechanically induced signal transduction has an essential role in development. Cells actively transduce and respond to mechanical signals and their internal architecture must manage the associated forces while also being dynamically responsive. With unique assembly-disassembly dynamics and physical properties, cytoplasmic intermediate filaments play an important role in regulating cell shape and mechanical integrity. While this function has been recognized and appreciated for more than 30 years, continually emerging data also demonstrate important roles of intermediate filaments in cell signal transduction. In this review, with a particular focus on keratins and vimentin, the relationship between the physical state of intermediate filaments and their role in mechanotransduction signaling is illustrated through a survey of current literature. Association with adhesion receptors such as cadherins and integrins provides a critical interface through which intermediate filaments are exposed to forces from a cell's environment. As a consequence, these cytoskeletal networks are posttranslationally modified, remodeled and reorganized with direct impacts on local signal transduction events and cell migratory behaviors important to development. We propose that intermediate filaments provide an opportune platform for cells to both cope with mechanical forces and modulate signal transduction.
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Affiliation(s)
- Rucha Sanghvi-Shah
- Department of Biological Sciences, Rutgers University-NewarkNewark, NJ, United States
| | - Gregory F Weber
- Department of Biological Sciences, Rutgers University-NewarkNewark, NJ, United States
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35
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Balikov DA, Brady SK, Ko UH, Shin JH, de Pereda JM, Sonnenberg A, Sung HJ, Lang MJ. The nesprin-cytoskeleton interface probed directly on single nuclei is a mechanically rich system. Nucleus 2017. [PMID: 28640691 DOI: 10.1080/19491034.2017.1322237] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The cytoskeleton provides structure and plays an important role in cellular function such as migration, resisting compression forces, and transport. The cytoskeleton also reacts to physical cues such as fluid shear stress or extracellular matrix remodeling by reorganizing filament associations, most commonly focal adhesions and cell-cell cadherin junctions. These mechanical stimuli can result in genome-level changes, and the physical connection of the cytoskeleton to the nucleus provides an optimal conduit for signal transduction by interfacing with nuclear envelope proteins, called nesprins, within the LINC (linker of the nucleus to the cytoskeleton) complex. Using single-molecule on single nuclei assays, we report that the interactions between the nucleus and the cytoskeleton, thought to be nesprin-cytoskeleton interactions, are highly sensitive to force magnitude and direction depending on whether cells are historically interfaced with the matrix or with cell aggregates. Application of ∼10-30 pN forces to these nesprin linkages yielded structural transitions, with a base transition size of 5-6 nm, which are speculated to be associated with partial unfoldings of the spectrin domains of the nesprins and/or structural changes of histones within the nucleus.
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Affiliation(s)
- Daniel A Balikov
- a Department of Biomedical Engineering , Vanderbilt University , Nashville , TN , USA
| | - Sonia K Brady
- b Department of Chemical and Biomolecular Engineering , Vanderbilt University , Nashville , TN , USA
| | - Ung Hyun Ko
- c Department of Mechanical Engineering , Korea Advanced Institute of Science and Technology , Daejeon , Korea
| | - Jennifer H Shin
- c Department of Mechanical Engineering , Korea Advanced Institute of Science and Technology , Daejeon , Korea
| | - Jose M de Pereda
- d Instituto de Biologia Molecular y Celular del Cancer, Consejo Superior de Investigaciones Cientificas , University of Salamanca , Salamanca , Spain
| | | | - Hak-Joon Sung
- a Department of Biomedical Engineering , Vanderbilt University , Nashville , TN , USA.,f Division of Cardiovascular Medicine, Department of Medicine , Vanderbilt University Medical Center , Nashville , TN , USA.,g Severance Biomedical Science Institute, College of Medicine , Yonsei University , Seoul , Republic of Korea
| | - Matthew J Lang
- b Department of Chemical and Biomolecular Engineering , Vanderbilt University , Nashville , TN , USA.,h Department of Molecular Physiology and Biophysics , Vanderbilt University Medical Center , Nashville , TN , USA.,i SMART-BioSystems and Micromechanics , National University of Singapore , Singapore
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36
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Tariq Z, Zhang H, Chia-Liu A, Shen Y, Gete Y, Xiong ZM, Tocheny C, Campanello L, Wu D, Losert W, Cao K. Lamin A and microtubules collaborate to maintain nuclear morphology. Nucleus 2017; 8:433-446. [PMID: 28557611 DOI: 10.1080/19491034.2017.1320460] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Lamin A (LA) is a critical structural component of the nuclear lamina. Mutations within the LA gene (LMNA) lead to several human disorders, most striking of which is Hutchinson-Gilford Progeria Syndrome (HGPS), a premature aging disorder. HGPS cells are best characterized by an abnormal nuclear morphology known as nuclear blebbing, which arises due to the accumulation of progerin, a dominant mutant form of LA. The microtubule (MT) network is known to mediate changes in nuclear morphology in the context of specific events such as mitosis, cell polarization, nucleus positioning and cellular migration. What is less understood is the role of the microtubule network in determining nuclear morphology during interphase. In this study, we elucidate the role of the cytoskeleton in regulation and misregulation of nuclear morphology through perturbations of both the lamina and the microtubule network. We found that LA knockout cells exhibit a crescent shape morphology associated with the microtubule-organizing center. Furthermore, this crescent shape ameliorates upon treatment with MT drugs, Nocodazole or Taxol. Expression of progerin, in LA knockout cells also rescues the crescent shape, although the response to Nocodazole or Taxol treatment is altered in comparison to cells expressing LA. Together these results describe a collaborative effort between LA and the MT network to maintain nuclear morphology.
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Affiliation(s)
- Zeshan Tariq
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
| | - Haoyue Zhang
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
| | - Alexander Chia-Liu
- b Department of Physics , University of Maryland , College Park , MD , USA
| | - Yang Shen
- b Department of Physics , University of Maryland , College Park , MD , USA
| | - Yantenew Gete
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
| | - Zheng-Mei Xiong
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
| | - Claire Tocheny
- c Department of Biology , The College of William and Mary , Williamsburg , VA , USA
| | - Leonard Campanello
- b Department of Physics , University of Maryland , College Park , MD , USA
| | - Di Wu
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
| | - Wolfgang Losert
- b Department of Physics , University of Maryland , College Park , MD , USA
| | - Kan Cao
- a Department of Cell Biology and Molecular Genetics , University of Maryland , College Park , MD , USA
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37
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Rauschert I, Aldunate F, Preussner J, Arocena-Sutz M, Peraza V, Looso M, Benech JC, Agrelo R. Promoter hypermethylation as a mechanism for Lamin A/C silencing in a subset of neuroblastoma cells. PLoS One 2017; 12:e0175953. [PMID: 28422997 PMCID: PMC5397038 DOI: 10.1371/journal.pone.0175953] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Accepted: 04/03/2017] [Indexed: 02/07/2023] Open
Abstract
Nuclear lamins support the nuclear envelope and provide anchorage sites for chromatin. They are involved in DNA synthesis, transcription, and replication. It has previously been reported that the lack of Lamin A/C expression in lymphoma and leukaemia is due to CpG island promoter hypermethylation. Here, we provide evidence that Lamin A/C is silenced via this mechanism in a subset of neuroblastoma cells. Moreover, Lamin A/C expression can be restored with a demethylating agent. Importantly, Lamin A/C reintroduction reduced cell growth kinetics and impaired migration, invasion, and anchorage-independent cell growth. Cytoskeletal restructuring was also induced. In addition, the introduction of lamin Δ50, known as Progerin, caused senescence in these neuroblastoma cells. These cells were stiffer and developed a cytoskeletal structure that differed from that observed upon Lamin A/C introduction. Of relevance, short hairpin RNA Lamin A/C depletion in unmethylated neuroblastoma cells enhanced the aforementioned tumour properties. A cytoskeletal structure similar to that observed in methylated cells was induced. Furthermore, atomic force microscopy revealed that Lamin A/C knockdown decreased cellular stiffness in the lamellar region. Finally, the bioinformatic analysis of a set of methylation arrays of neuroblastoma primary tumours showed that a group of patients (around 3%) gives a methylation signal in some of the CpG sites located within the Lamin A/C promoter region analysed by bisulphite sequencing PCR. These findings highlight the importance of Lamin A/C epigenetic inactivation for a subset of neuroblastomas, leading to enhanced tumour properties and cytoskeletal changes. Additionally, these findings may have treatment implications because tumour cells lacking Lamin A/C exhibit more aggressive behaviour.
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Affiliation(s)
- Ines Rauschert
- Laboratory of Cellular Signaling and Nanobiology, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Fabian Aldunate
- Epigenetics of Cancer and Aging Laboratory, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Jens Preussner
- Bioinformatics Core Unit (BCU), Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Miguel Arocena-Sutz
- Epigenetics of Cancer and Aging Laboratory, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Vanina Peraza
- Epigenetics of Cancer and Aging Laboratory, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Mario Looso
- Bioinformatics Core Unit (BCU), Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Juan C. Benech
- Laboratory of Cellular Signaling and Nanobiology, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Ruben Agrelo
- Epigenetics of Cancer and Aging Laboratory, Institut Pasteur de Montevideo, Montevideo, Uruguay
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38
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Saunders CA, Harris NJ, Willey PT, Woolums BM, Wang Y, McQuown AJ, Schoenhofen A, Worman HJ, Dauer WT, Gundersen GG, Luxton GWG. TorsinA controls TAN line assembly and the retrograde flow of dorsal perinuclear actin cables during rearward nuclear movement. J Cell Biol 2017; 216:657-674. [PMID: 28242745 PMCID: PMC5350507 DOI: 10.1083/jcb.201507113] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/04/2016] [Accepted: 12/21/2016] [Indexed: 12/29/2022] Open
Abstract
The nucleus is positioned toward the rear of most migratory cells. In fibroblasts and myoblasts polarizing for migration, retrograde actin flow moves the nucleus rearward, resulting in the orientation of the centrosome in the direction of migration. In this study, we report that the nuclear envelope-localized AAA+ (ATPase associated with various cellular activities) torsinA (TA) and its activator, the inner nuclear membrane protein lamina-associated polypeptide 1 (LAP1), are required for rearward nuclear movement during centrosome orientation in migrating fibroblasts. Both TA and LAP1 contributed to the assembly of transmembrane actin-associated nuclear (TAN) lines, which couple the nucleus to dorsal perinuclear actin cables undergoing retrograde flow. In addition, TA localized to TAN lines and was necessary for the proper mobility of EGFP-mini-nesprin-2G, a functional TAN line reporter construct, within the nuclear envelope. Furthermore, TA and LAP1 were indispensable for the retrograde flow of dorsal perinuclear actin cables, supporting the recently proposed function for the nucleus in spatially organizing actin flow and cytoplasmic polarity. Collectively, these results identify TA as a key regulator of actin-dependent rearward nuclear movement during centrosome orientation.
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Affiliation(s)
- Cosmo A Saunders
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Nathan J Harris
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Patrick T Willey
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Brian M Woolums
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Yuexia Wang
- Department of Medicine, Columbia University, New York, NY 10032.,Department of Pathology and Cell Biology, Columbia University, New York, NY 10032
| | - Alex J McQuown
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Amy Schoenhofen
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
| | - Howard J Worman
- Department of Medicine, Columbia University, New York, NY 10032.,Department of Pathology and Cell Biology, Columbia University, New York, NY 10032
| | - William T Dauer
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109.,Department of Neurology, University of Michigan, Ann Arbor, MI 48109
| | - Gregg G Gundersen
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032
| | - G W Gant Luxton
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455
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39
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Hieda M. Implications for Diverse Functions of the LINC Complexes Based on the Structure. Cells 2017; 6:cells6010003. [PMID: 28134781 PMCID: PMC5371868 DOI: 10.3390/cells6010003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 01/15/2017] [Accepted: 01/17/2017] [Indexed: 12/18/2022] Open
Abstract
The linker of nucleoskeleton and cytoskeleton (LINC) complex is composed of the outer and inner nuclear membrane protein families Klarsicht, Anc-1, and Syne homology (KASH), and Sad1 and UNC-84 (SUN) homology domain proteins. Increasing evidence has pointed to diverse functions of the LINC complex, such as in nuclear migration, nuclear integrity, chromosome movement and pairing during meiosis, and mechanotransduction to the genome. In metazoan cells, the nuclear envelope possesses the nuclear lamina, which is a thin meshwork of intermediate filaments known as A-type and B-type lamins and lamin binding proteins. Both of lamins physically interact with the inner nuclear membrane spanning SUN proteins. The nuclear lamina has also been implicated in various functions, including maintenance of nuclear integrity, mechanotransduction, cellular signalling, and heterochromatin dynamics. Thus, it is clear that the LINC complex and nuclear lamins perform diverse but related functions. However, it is unknown whether the LINC complex-lamins interactions are involved in these diverse functions, and their regulation mechanism has thus far been elusive. Recent structural analysis suggested a dynamic nature of the LINC complex component, thus providing an explanation for LINC complex organization. This review, elaborating on the integration of crystallographic and biochemical data, helps to integrate this research to gain a better understanding of the diverse functions of the LINC complex.
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Affiliation(s)
- Miki Hieda
- Department of Medical Technology, Ehime Prefectural University of Health Sciences, Ehime 791-2101, Japan.
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40
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Xiao PJ, Mitchell AM, Huang L, Li C, Samulski RJ. Disruption of Microtubules Post-Virus Entry Enhances Adeno-Associated Virus Vector Transduction. Hum Gene Ther 2016; 27:309-24. [PMID: 26942476 DOI: 10.1089/hum.2016.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Perinuclear retention of viral particles is a poorly understood phenomenon observed during many virus infections. In this study, we investigated whether perinuclear accumulation acts as a barrier to limit recombinant adeno-associated virus (rAAV) transduction. After nocodazole treatment to disrupt microtubules at microtubule-organization center (MT-MTOC) after virus entry, we observed higher rAAV transduction. To elucidate the role of MT-MTOC in rAAV infection and study its underlying mechanisms, we demonstrated that rAAV's perinuclear localization was retained by MT-MTOC with fluorescent analysis, and enhanced rAAV transduction from MT-MTOC disruption was dependent on the rAAV capsid's nuclear import signals. Interestingly, after knocking down RhoA or inhibiting its downstream effectors (ROCK and Actin), MT-MTOC disruption failed to increase rAAV transduction or nuclear entry. These data suggest that enhancement of rAAV transduction is the result of increased trafficking to the nucleus via the RhoA-ROCK-Actin pathway. Ten-fold higher rAAV transduction was also observed by disrupting MT-MTOC in brain, liver, and tumor in vivo. In summary, this study indicates that virus perinuclear accumulation at MT-MTOC is a barrier-limiting parameter for effective rAAV transduction and defines a novel defense mechanism by which host cells restrain viral invasion.
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Affiliation(s)
- Ping-Jie Xiao
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.,2 Cell and Developmental Biology, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Angela M Mitchell
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.,3 Department of Microbiology and Immunology, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Lu Huang
- 4 Department of Statistics, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - Chengwen Li
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
| | - R Jude Samulski
- 1 Gene Therapy Center, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.,5 Department of Pharmacology, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina
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41
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In silico synchronization reveals regulators of nuclear ruptures in lamin A/C deficient model cells. Sci Rep 2016; 6:30325. [PMID: 27461848 PMCID: PMC4962089 DOI: 10.1038/srep30325] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 07/04/2016] [Indexed: 11/23/2022] Open
Abstract
The nuclear lamina is a critical regulator of nuclear structure and function. Nuclei from laminopathy patient cells experience repetitive disruptions of the nuclear envelope, causing transient intermingling of nuclear and cytoplasmic components. The exact causes and consequences of these events are not fully understood, but their stochastic occurrence complicates in-depth analyses. To resolve this, we have established a method that enables quantitative investigation of spontaneous nuclear ruptures, based on co-expression of a firmly bound nuclear reference marker and a fluorescent protein that shuttles between the nucleus and cytoplasm during ruptures. Minimally invasive imaging of both reporters, combined with automated tracking and in silico synchronization of individual rupture events, allowed extracting information on rupture frequency and recovery kinetics. Using this approach, we found that rupture frequency correlates inversely with lamin A/C levels, and can be reduced in genome-edited LMNA knockout cells by blocking actomyosin contractility or inhibiting the acetyl-transferase protein NAT10. Nuclear signal recovery followed a kinetic that is co-determined by the severity of the rupture event, and could be prolonged by knockdown of the ESCRT-III complex component CHMP4B. In conclusion, our approach reveals regulators of nuclear rupture induction and repair, which may have critical roles in disease development.
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42
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Under Pressure: Mechanical Stress Management in the Nucleus. Cells 2016; 5:cells5020027. [PMID: 27314389 PMCID: PMC4931676 DOI: 10.3390/cells5020027] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/03/2016] [Accepted: 06/06/2016] [Indexed: 12/23/2022] Open
Abstract
Cells are constantly adjusting to the mechanical properties of their surroundings, operating a complex mechanochemical feedback, which hinges on mechanotransduction mechanisms. Whereas adhesion structures have been shown to play a central role in mechanotransduction, it now emerges that the nucleus may act as a mechanosensitive structure. Here, we review recent advances demonstrating that mechanical stress emanating from the cytoskeleton can activate pathways in the nucleus which eventually impact both its structure and the transcriptional machinery.
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43
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Spagnol ST, Armiger TJ, Dahl KN. Mechanobiology of Chromatin and the Nuclear Interior. Cell Mol Bioeng 2016; 9:268-276. [PMID: 28163791 PMCID: PMC5289645 DOI: 10.1007/s12195-016-0444-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 05/03/2016] [Indexed: 02/06/2023] Open
Abstract
The view of the cell nucleus has evolved from an isolated, static organelle to a dynamic structure integrated with other mechanical elements of the cell. Both dynamics and integration appear to contribute to a mechanical regulation of genome expression. Here, we review physical structures inside the nucleus at different length scales and the dynamic reorganization modulated by cellular forces. First, we discuss nuclear organization focusing on self-assembly and disassembly of DNA structures and various nuclear bodies. We then discuss the importance of connections from the chromatin fiber through the nuclear envelope to the rest of the cell as they relate to mechanobiology. Finally, we discuss how cell stimulation, both chemical and physical, can alter nuclear structures and ultimately cellular function in healthy cells and in some model diseases. The view of chromatin and nuclear bodies as mechanical entities integrated with force generation from the cytoskeleton combines polymer physics with cell biology and medicine.
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Affiliation(s)
- Stephen T. Spagnol
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
| | - Travis J. Armiger
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
| | - Kris Noel Dahl
- Department of Chemical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, USA
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44
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Lottersberger F, Karssemeijer RA, Dimitrova N, de Lange T. 53BP1 and the LINC Complex Promote Microtubule-Dependent DSB Mobility and DNA Repair. Cell 2016; 163:880-93. [PMID: 26544937 DOI: 10.1016/j.cell.2015.09.057] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/14/2015] [Accepted: 09/28/2015] [Indexed: 01/13/2023]
Abstract
Increased mobility of chromatin surrounding double-strand breaks (DSBs) has been noted in yeast and mammalian cells but the underlying mechanism and its contribution to DSB repair remain unclear. Here, we use a telomere-based system to track DNA damage foci with high resolution in living cells. We find that the greater mobility of damaged chromatin requires 53BP1, SUN1/2 in the linker of the nucleoskeleton, and cytoskeleton (LINC) complex and dynamic microtubules. The data further demonstrate that the excursions promote non-homologous end joining of dysfunctional telomeres and implicated Nesprin-4 and kinesins in telomere fusion. 53BP1/LINC/microtubule-dependent mobility is also evident at irradiation-induced DSBs and contributes to the mis-rejoining of drug-induced DSBs in BRCA1-deficient cells showing that DSB mobility can be detrimental in cells with numerous DSBs. In contrast, under physiological conditions where cells have only one or a few lesions, DSB mobility is proposed to prevent errors in DNA repair.
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Affiliation(s)
- Francisca Lottersberger
- Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Roos Anna Karssemeijer
- Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Nadya Dimitrova
- Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Titia de Lange
- Laboratory for Cell Biology and Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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45
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MCLIP Detection of Novel Protein–Protein Interactions at the Nuclear Envelope. Methods Enzymol 2016; 569:503-15. [DOI: 10.1016/bs.mie.2015.08.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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46
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Espigat-Georger A, Dyachuk V, Chemin C, Emorine L, Merdes A. Nuclear alignment in myotubes requires centrosome proteins recruited by nesprin-1. J Cell Sci 2016; 129:4227-4237. [DOI: 10.1242/jcs.191767] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 09/26/2016] [Indexed: 01/26/2023] Open
Abstract
Myotubes are syncytial cells, generated by fusion of myoblasts. Among the numerous nuclei in myotubes of skeletal muscle fibres, the majority are equidistantly positioned at the periphery, except for clusters of multiple nuclei underneath the motor endplate. The correct positioning of nuclei is thought to be important for muscle function and requires nesprin-1, a protein of the nuclear envelope. Consistently, mice lacking functional nesprin-1 show defective nuclear positioning and mimic aspects of Emery-Dreifuss muscular dystrophy. In this study, we perform siRNA experiments in C2C12 myoblasts undergoing differentiation, demonstrating that the positioning of nuclei requires PCM-1, a protein of the centrosome that relocalizes to the nuclear envelope at the onset of differentiation, dependent on the presence of nesprin-1. PCM-1 itself is required for recruiting proteins of the dynein/dynactin complex and of kinesin motor complexes. This suggests that microtubule motors that are attached to the nuclear envelope support the movement of nuclei along microtubules, to ensure correct positioning in the myotube.
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Affiliation(s)
- Aude Espigat-Georger
- Centre de Biologie du Développement, Université Paul Sabatier/CNRS, 31062 Toulouse, France
| | - Vyacheslav Dyachuk
- Centre de Biologie du Développement, Université Paul Sabatier/CNRS, 31062 Toulouse, France
| | - Cécile Chemin
- Centre de Biologie du Développement, Université Paul Sabatier/CNRS, 31062 Toulouse, France
| | - Laurent Emorine
- Centre de Biologie du Développement, Université Paul Sabatier/CNRS, 31062 Toulouse, France
| | - Andreas Merdes
- Centre de Biologie du Développement, Université Paul Sabatier/CNRS, 31062 Toulouse, France
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47
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Kim DI, Birendra KC, Roux KJ. Making the LINC: SUN and KASH protein interactions. Biol Chem 2015; 396:295-310. [PMID: 25720065 DOI: 10.1515/hsz-2014-0267] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 01/20/2015] [Indexed: 01/15/2023]
Abstract
Cell nuclei are physically integrated with the cytoskeleton through the linker of nucleoskeleton and cytoskeleton (LINC) complex, a structure that spans the nuclear envelope to link the nucleoskeleton and cytoskeleton. Outer nuclear membrane KASH domain proteins and inner nuclear membrane SUN domain proteins interact to form the core of the LINC complex. In this review, we provide a comprehensive analysis of the reported protein-protein interactions for KASH and SUN domain proteins. This critical structure, directly connecting the genome with the rest of the cell, contributes to a myriad of cellular functions and, when perturbed, is associated with human disease.
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48
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Pasch E, Link J, Beck C, Scheuerle S, Alsheimer M. The LINC complex component Sun4 plays a crucial role in sperm head formation and fertility. Biol Open 2015; 4:1792-802. [PMID: 26621829 PMCID: PMC4736043 DOI: 10.1242/bio.015768] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
LINC complexes are evolutionarily conserved nuclear envelope bridges, physically connecting the nucleus to the peripheral cytoskeleton. They are pivotal for dynamic cellular and developmental processes, like nuclear migration, anchoring and positioning, meiotic chromosome movements and maintenance of cell polarity and nuclear shape. Active nuclear reshaping is a hallmark of mammalian sperm development and, by transducing cytoskeletal forces to the nuclear envelope, LINC complexes could be vital for sperm head formation as well. We here analyzed in detail the behavior and function of Sun4, a bona fide testis-specific LINC component. We demonstrate that Sun4 is solely expressed in spermatids and there localizes to the posterior nuclear envelope, likely interacting with Sun3/Nesprin1 LINC components. Our study revealed that Sun4 deficiency severely impacts the nucleocytoplasmic junction, leads to mislocalization of other LINC components and interferes with the formation of the microtubule manchette, which finally culminates in a globozoospermia-like phenotype. Together, our study provides direct evidence for a critical role of LINC complexes in mammalian sperm head formation and male fertility.
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Affiliation(s)
- Elisabeth Pasch
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg D-97074, Germany
| | - Jana Link
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg D-97074, Germany
| | - Carolin Beck
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg D-97074, Germany
| | - Stefanie Scheuerle
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg D-97074, Germany
| | - Manfred Alsheimer
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg D-97074, Germany
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49
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Staszewska I, Fischer I, Wiche G. Plectin isoform 1-dependent nuclear docking of desmin networks affects myonuclear architecture and expression of mechanotransducers. Hum Mol Genet 2015; 24:7373-89. [PMID: 26487297 PMCID: PMC4664173 DOI: 10.1093/hmg/ddv438] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/12/2015] [Indexed: 12/16/2022] Open
Abstract
Plectin is a highly versatile cytoskeletal protein that acts as a mechanical linker between intermediate filament (IF) networks and various cellular structures. The protein is crucial for myofiber integrity. Its deficiency leads to severe pathological changes in skeletal muscle fibers of patients suffering from epidermolysis bullosa simplex with muscular dystrophy (EBS-MD). Skeletal muscle fibers express four major isoforms of plectin which are distinguished solely by alternative, relatively short, first exon-encoded N-terminal sequences. Each one of these isoforms is localized to a different subcellular compartment and plays a specific role in maintaining integrity and proper function(s) of myofibers. The unique role of individual isoforms is supported by distinct phenotypes of isoform-specific knockout mice and recently discovered mutations in first coding exons of plectin that lead to distinct, tissue-specific, pathological abnormalities in humans. In this study, we demonstrate that the lack of plectin isoform 1 (P1) in myofibers of mice leads to alterations of nuclear morphology, similar to those observed in various forms of MD. We show that P1-mediated targeting of desmin IFs to myonuclei is essential for maintenance of their typically spheroidal architecture as well as their proper positioning and movement along the myofiber. Furthermore, we show that P1 deficiency affects chromatin modifications and the expression of genes involved in various cellular functions, including signaling pathways mediating mechanotransduction. Mechanistically, P1 is shown to specifically interact with the myonuclear membrane-associated (BAR domain-containing) protein endophilin B. Our results open a new perspective on cytoskeleton-nuclear crosstalk via specific cytolinker proteins.
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Affiliation(s)
- Ilona Staszewska
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
| | - Irmgard Fischer
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
| | - Gerhard Wiche
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
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50
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Neelam S, Dickinson RB, Lele TP. New approaches for understanding the nuclear force balance in living, adherent cells. Methods 2015; 94:27-32. [PMID: 26115785 DOI: 10.1016/j.ymeth.2015.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 05/26/2015] [Accepted: 06/15/2015] [Indexed: 02/08/2023] Open
Abstract
Cytoskeletal forces are transmitted to the nucleus to position and shape it. Linkages mediated by the LINC (linker of nucleoskeleton and cytoskeleton) complex transfer these forces to the nuclear envelope. Nuclear position and shape can be thought to be determined by a balance of cytoskeletal forces generated by microtubule motors that shear the nuclear surface, actomyosin forces that can pull, push and shear the nucleus, and intermediate filaments that may passively resist nuclear decentering and deformation. Parsing contributions of these different forces to nuclear mechanics is a very challenging task. Here we review new approaches that can be used in living cells to probe and understand the nuclear force balance.
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Affiliation(s)
- Srujana Neelam
- Department of Biomedical Engineering, University of Florida, Gainesville FL 32611, United States
| | - Richard B Dickinson
- Department of Chemical Engineering, University of Florida, Gainesville FL 32611, United States
| | - Tanmay P Lele
- Department of Chemical Engineering, University of Florida, Gainesville FL 32611, United States.
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