Nuclear lamin A/C deficiency induces defects in cell mechanics, polarization, and migration.

Lamin A/C is a major constituent of the nuclear lamina, a thin filamentous protein layer that lies beneath the nuclear envelope. Here we show that lamin A/C deficiency in mouse embryonic fibroblasts (Lmna(-/-) MEFs) diminishes the ability of these cells to polarize at the edge of a wound and significantly reduces cell migration speed into the wound. Moreover, lamin A/C deficiency induces significant separation of the microtubule organizing center (MTOC) from the nuclear envelope. Investigations using ballistic intracellular nanorheology reveal that lamin A/C deficiency also dramatically affects the micromechanical properties of the cytoplasm. Both the elasticity (stretchiness) and the viscosity (propensity of a material to flow) of the cytoplasm in Lmna(-/-) MEFs are significantly reduced. Disassembly of either the actin filament or microtubule networks in Lmna(+/+) MEFs results in decrease of cytoplasmic elasticity and viscosity down to levels found in Lmna(-/-) MEFs. Together these results show that both the mechanical properties of the cytoskeleton and cytoskeleton-based processes, including cell motility, coupled MTOC and nucleus dynamics, and cell polarization, depend critically on the integrity of the nuclear lamina, which suggest the existence of a functional mechanical connection between the nucleus and the cytoskeleton. These results also suggest that cell polarization during cell migration requires tight mechanical coupling between MTOC and nucleus, which is mediated by lamin A/C.

[1]  Jerry S. H. Lee,et al.  Cdc42 mediates nucleus movement and MTOC polarization in Swiss 3T3 fibroblasts under mechanical shear stress. , 2004, Molecular biology of the cell.

[2]  G. Joberty,et al.  The cell-polarity protein Par6 links Par3 and atypical protein kinase C to Cdc42 , 2000, Nature Cell Biology.

[3]  K. Schwartz,et al.  Nuclear envelope alterations in fibroblasts from LGMD1B patients carrying nonsense Y259X heterozygous or homozygous mutation in lamin A/C gene. , 2003, Experimental cell research.

[4]  Yiider Tseng,et al.  Rho kinase regulates the intracellular micromechanical response of adherent cells to rho activation. , 2004, Molecular biology of the cell.

[5]  R. Hegele,et al.  Nuclear lamin A/C R482Q mutation in canadian kindreds with Dunnigan-type familial partial lipodystrophy. , 2000, Human molecular genetics.

[6]  S. A. Ruiz,et al.  Shape anisotropy of a single random-walk polymer. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[7]  Virgile Viasnoff,et al.  Compliance of actin filament networks measured by particle-tracking microrheology and diffusing wave spectroscopy , 1998 .

[8]  Denis Wirtz,et al.  Mechanics and dynamics of actin-driven thin membrane protrusions. , 2006, Biophysical journal.

[9]  T. Arimura,et al.  Genetics of laminopathies. , 2005, Novartis Foundation symposium.

[10]  J. Ahringer,et al.  The C. elegans Hook Protein, ZYG-12, Mediates the Essential Attachment between the Centrosome and Nucleus , 2003, Cell.

[11]  Min Han,et al.  Role of ANC-1 in Tethering Nuclei to the Actin Cytoskeleton , 2002, Science.

[12]  C. Oomens,et al.  Decreased mechanical stiffness in LMNA-/- cells is caused by defective nucleo-cytoskeletal integrity: implications for the development of laminopathies. , 2004, Human molecular genetics.

[13]  D. Fatkin,et al.  Defects in nuclear structure and function promote dilated cardiomyopathy in lamin A/C-deficient mice. , 2004, The Journal of clinical investigation.

[14]  L. Mounkes,et al.  A progeroid syndrome in mice is caused by defects in A-type lamins , 2003, Nature.

[15]  J. Seidman,et al.  Missense mutations in the rod domain of the lamin A/C gene as causes of dilated cardiomyopathy and conduction-system disease. , 1999, The New England journal of medicine.

[16]  F. Muntoni,et al.  Mutations in the gene encoding lamin A/C cause autosomal dominant Emery-Dreifuss muscular dystrophy , 1999, Nature Genetics.

[17]  D. Wirtz,et al.  The Bimodal Role of Filamin in Controlling the Architecture and Mechanics of F-actin Networks* , 2004, Journal of Biological Chemistry.

[18]  C. Hutchison.  Lamins: building blocks or regulators of gene expression? , 2002, Nature Reviews Molecular Cell Biology.

[19]  Miguel A del Pozo,et al.  Localized Cdc42 Activation, Detected Using a Novel Assay, Mediates Microtubule Organizing Center Positioning in Endothelial Cells in Response to Fluid Shear Stress* , 2003, Journal of Biological Chemistry.

[20]  U Aebi,et al.  Nuclear lamins: their structure, assembly, and interactions. , 1998, Journal of structural biology.

[21]  Denis Wirtz,et al.  Morphology of the lamellipodium and organization of actin filaments at the leading edge of crawling cells. , 2005, Biophysical journal.

[22]  T. Tuschl,et al.  Duplexes of 21-nucleotide RNAs mediate RNA interference in cultured mammalian cells , 2001, Nature.

[23]  C. Stewart,et al.  Life at the edge: the nuclear envelope and human disease , 2002, Nature Reviews Molecular Cell Biology.

[24]  Richard T. Lee,et al.  Lamin A/C deficiency causes defective nuclear mechanics and mechanotransduction. , 2004, The Journal of clinical investigation.

[25]  Katherine L. Wilson,et al.  The nuclear lamina comes of age , 2005, Nature Reviews Molecular Cell Biology.

[26]  J. Rottman,et al.  Expression of an LMNA-N195K variant of A-type lamins results in cardiac conduction defects and death in mice. , 2005, Human molecular genetics.

[27]  D. Wirtz,et al.  Intracellular microrheology as a tool for the measurement of the local mechanical properties of live cells. , 2004, Methods in cell biology.

[28]  R. Goldman,et al.  Nuclear lamins: building blocks of nuclear structure and function. , 2005, Novartis Foundation symposium.

[29]  K. Wilson,et al.  Proteins that bind A-type lamins: integrating isolated clues , 2004, Journal of Cell Science.

[30]  Brian Burke,et al.  Loss of a-Type Lamin Expression Compromises Nuclear Envelope Integrity Leading to Muscular Dystrophy , 1999, The Journal of cell biology.

[31]  Yiider Tseng,et al.  Ballistic intracellular nanorheology reveals ROCK-hard cytoplasmic stiffening response to fluid flow , 2006, Journal of Cell Science.

[32]  D. Ingber,et al.  Probing transmembrane mechanical coupling and cytomechanics using magnetic twisting cytometry. , 1995, Biochemistry and cell biology = Biochimie et biologie cellulaire.

[33]  Min Han,et al.  ANChors away: an actin based mechanism of nuclear positioning , 2003, Journal of Cell Science.

[34]  S. Varnous,et al.  Mouse model carrying H222P-Lmna mutation develops muscular dystrophy and dilated cardiomyopathy similar to human striated muscle laminopathies. , 2005, Human molecular genetics.

[35]  Yiider Tseng,et al.  Micromechanical mapping of live cells by multiple-particle-tracking microrheology. , 2002, Biophysical journal.

[36]  H. Horvitz,et al.  UNC-84 localizes to the nuclear envelope and is required for nuclear migration and anchoring during C. elegans development. , 1999, Development.

[37]  Laura Scott,et al.  Recurrent de novo point mutations in lamin A cause Hutchinson–Gilford progeria syndrome , 2003, Nature.

[38]  C. S. Chen,et al.  Demonstration of mechanical connections between integrins, cytoskeletal filaments, and nucleoplasm that stabilize nuclear structure. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[39]  Min Han,et al.  Lamin-dependent localization of UNC-84, a protein required for nuclear migration in Caenorhabditis elegans. , 2002, Molecular biology of the cell.

[40]  C. Stewart,et al.  The laminopathies: nuclear structure meets disease. , 2003, Current opinion in genetics & development.

[41]  C. Stewart,et al.  Homozygous defects in LMNA, encoding lamin A/C nuclear-envelope proteins, cause autosomal recessive axonal neuropathy in human (Charcot-Marie-Tooth disorder type 2) and mouse. , 2002, American journal of human genetics.

[42]  E. Sackmann,et al.  Measurement of local viscoelasticity and forces in living cells by magnetic tweezers. , 1999, Biophysical journal.

[43]  Denis Wirtz,et al.  Particle Tracking Microrheology of Complex Fluids , 1997 .

[44]  Yiider Tseng,et al.  Microrheology and ROCK signaling of human endothelial cells embedded in a 3D matrix. , 2006, Biophysical journal.

[45]  A. Palmer,et al.  Diffusing wave spectroscopy microrheology of actin filament networks. , 1999, Biophysical journal.

[46]  A. Hall,et al.  Cdc42 regulates GSK-3β and adenomatous polyposis coli to control cell polarity , 2003, Nature.

[47]  Yiider Tseng,et al.  Intracellular mechanics of migrating fibroblasts. , 2004, Molecular biology of the cell.

[48]  M. Bergo,et al.  Lamin B1 is required for mouse development and nuclear integrity. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[49]  E. Fedorov,et al.  Multiple-particle tracking measurements of heterogeneities in solutions of actin filaments and actin bundles. , 2000, Biophysical journal.

[50]  Qian Liu,et al.  Citation for Published Item: Use Policy Coupling of the Nucleus and Cytoplasm: Role of the Linc Complex , 2022 .

[51]  A. Hall,et al.  Integrin-Mediated Activation of Cdc42 Controls Cell Polarity in Migrating Astrocytes through PKCζ , 2001, Cell.

[52]  T. Svitkina,et al.  Correlative light and electron microscopy of the cytoskeleton of cultured cells. , 1998, Methods in enzymology.

[53]  M. Hetzer,et al.  Pushing the envelope: structure, function, and dynamics of the nuclear periphery. , 2005, Annual review of cell and developmental biology.

[54]  R. Vallee,et al.  Cdc42, dynein, and dynactin regulate MTOC reorientation independent of Rho-regulated microtubule stabilization , 2001, Current Biology.

[55]  J. Bridger,et al.  Aging of Hutchinson–Gilford progeria syndrome fibroblasts is characterised by hyperproliferation and increased apoptosis , 2004, Experimental Gerontology.

[56]  A. Csoka,et al.  Novel lamin A/C gene (LMNA) mutations in atypical progeroid syndromes , 2004, Journal of Medical Genetics.

[57]  G. Scarano,et al.  Mandibuloacral dysplasia is caused by a mutation in LMNA-encoding lamin A/C. , 2002, American journal of human genetics.

[58]  A. Noegel,et al.  NUANCE, a giant protein connecting the nucleus and actin cytoskeleton. , 2002, Journal of cell science.