title: Novel nesprin-1 mutations associated with dilated cardiomyopathy cause nuclear envelope disruption and defects in myogenesis.
abstract: Nesprins-1 and -2 are highly expressed in skeletal and cardiac muscle and together with SUN (Sad1p/UNC84)-domain containing proteins and lamin A/C form the LInker of Nucleoskeleton-and-Cytoskeleton (LINC) bridging complex at the nuclear envelope (NE). Mutations in nesprin-1/2 have previously been found in patients with autosomal dominant Emery-Dreifuss muscular dystrophy (EDMD) as well as dilated cardiomyopathy (DCM). In this study, three novel rare variants (R8272Q, S8381C and N8406K) in the C-terminus of the SYNE1 gene (nesprin-1) were identified in seven DCM patients by mutation screening. Expression of these mutants caused nuclear morphology defects and reduced lamin A/C and SUN2 staining at the NE. GST pull-down indicated that nesprin-1/lamin/SUN interactions were disrupted. Nesprin-1 mutations were also associated with augmented activation of the ERK pathway in vitro and in hearts in vivo. During C2C12 muscle cell differentiation, nesprin-1 levels are increased concomitantly with kinesin light chain (KLC-1/2) and immunoprecipitation and GST pull-down showed that these proteins interacted via a recently identified LEWD domain in the C-terminus of nesprin-1. Expression of nesprin-1 mutants in C2C12 cells caused defects in myoblast differentiation and fusion associated with dysregulation of myogenic transcription factors and disruption of the nesprin-1 and KLC-1/2 interaction at the outer nuclear membrane. Expression of nesprin-1α2 WT and mutants in zebrafish embryos caused heart developmental defects that varied in severity. These findings support a role for nesprin-1 in myogenesis and muscle disease, and uncover a novel mechanism whereby disruption of the LINC complex may contribute to the pathogenesis of DCM.
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5 9NU, UK.|Department of Cardiology, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Can
authors.initials: C
authors.lastname: Zhou
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5 9NU, UK.|Department of Cardiology, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.affiliation: Laboratory of Molecular Translational Medicine.|Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education.|SCU-CUHK Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.
authors.forename: Huaqin
authors.initials: H
authors.lastname: Sun
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5 9NU, UK.|Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 9HN, UK.
authors.forename: Victoria
authors.initials: V
authors.lastname: Koullourou
authors.affiliation: Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10?7AG, UK and Institute for Science and Technology in Medicine, Keele University, ST5?5BG, UK.
authors.forename: Ian
authors.initials: I
authors.lastname: Holt
authors.affiliation: Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
authors.forename: Megan J
authors.initials: MJ
authors.lastname: Puckelwartz
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5?9NU, UK.
authors.forename: Derek T
authors.initials: DT
authors.lastname: Warren
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5?9NU, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Hayward
authors.affiliation: Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education.|SCU-CUHK Joint Laboratory for Reproductive Medicine, West China Second University Hospital, Sichuan University, Chengdu, 610041, China.
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Laboratory of Molecular Translational Medicine.|Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10?7AG, UK and Institute for Science and Technology in Medicine, Keele University, ST5?5BG, UK.
authors.forename: Glenn E
authors.initials: GE
authors.lastname: Morris
authors.affiliation: Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: McNally
authors.affiliation: Department of Molecular and Cell Biology, University of Leicester, Leicester LE1?9HN, UK.
authors.forename: Sue
authors.initials: S
authors.lastname: Shackleton
authors.affiliation: Department of Cardiology, West China Hospital of Sichuan University, Chengdu 610041, China.
authors.forename: Li
authors.initials: L
authors.lastname: Rao
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5?9NU, UK.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Shanahan
authors.affiliation: King's College London British Heart Foundation Centre of Research Excellence, Cardiovascular Division, London SE5?9NU, UK.
authors.forename: Qiuping
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002311:Cardiomyopathy, Dilated / Q000235:genetics / Q000378:metabolism; D018929:Cell Culture Techniques; D003598:Cytoskeletal Proteins; D003599:Cytoskeleton / Q000378:metabolism; D006801:Humans; D016547:Kinesins; D034904:Lamin Type A / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D008840:Microfilament Proteins / Q000235:genetics; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D024510:Muscle Development / Q000235:genetics / Q000502:physiology; D020389:Muscular Dystrophy, Emery-Dreifuss / Q000235:genetics; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism*; D009685:Nuclear Envelope / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D015027:Zebrafish / Q000235:genetics
chemical_list: D003598:Cytoskeletal Proteins; C000715688:KLC1 protein, human; D034904:Lamin Type A; D008565:Membrane Proteins; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C415465:SYNE1 protein, human; D016547:Kinesins