Beta1-integrins co-localize with Na, K-ATPase, epithelial sodium channels (ENaC) and voltage activated calcium channels (VACC) in mechanoreceptor complexes of mouse limb-bud chondrocytes.

Interactions between chondrocytes and their extracellular matrix are partly mediated by beta1-integrin receptors. Recent studies have shown that beta1-integrins co-localize with a variety of cytoskeletal complexes, signaling proteins and growth factor receptors. Since mechanosensitive ion channels and integrins have been proposed to participate in skeletal mechanotransduction, in this study, we investigated the possible co-localization of beta1-integrins with two ion channels and a P-type ATPase in mouse limb-bud chondrocytes. The alpha subunits of Na, K-ATPase, the epithelial sodium channel (ENaC) and the voltage activated calcium channel (VACC) were immunostained in organoid cultures derived from limb-buds of 12-day-old mice using well-characterized antibodies. Indirect immunofluorescence revealed abundant expression of beta1-integrins and each of the selected systems in limb-bud chondrocytes. Two-fluorochrome immunostaining demonstrated that beta1-integrin, Na, K-ATPase, ENaC and VACC co-localize in chondrocytes. Co-imunoprecipitation experiments revealed co-localization and association of integrins with ENaC, VACC and Na, K-ATPase. Cellular responses and signaling cascades initiated by the influx of calcium or sodium through putative mechanosensitive channels may be regulated more effectively if such channels were organized around integrins with receptors, kinases and cytoskeletal complexes clustered about them. The close proximity of ATPase ion pumps such as Na, K-ATPase to chondrocyte mechanoreceptor complexes could facilitate rapid homeostatic responses to the ionic perturbations brought about by activation of mechanically gated cation channels and efficiently regulate the intracellular milieu of chondrocytes.

[1]  A. Mobasheri,et al.  Glucose transport and metabolism in chondrocytes: a key to understanding chondrogenesis, skeletal development and cartilage degradation in osteoarthritis. , 2002, Histology and histopathology.

[2]  A. Mobasheri,et al.  Role of chondrocyte death and hypocellularity in ageing human articular cartilage and the pathogenesis of osteoarthritis. , 2002, Medical hypotheses.

[3]  A. Mobasheri,et al.  INTEGRINS AND STRETCH ACTIVATED ION CHANNELS; PUTATIVE COMPONENTS OF FUNCTIONAL CELL SURFACE MECHANORECEPTORS IN ARTICULAR CHONDROCYTES , 2002, Cell biology international.

[4]  A. Mobasheri,et al.  Sodium potassium pumps, epithelial sodium channels and voltage gated calcium channels colocalize with β1-integrins in mouse limb-bud chondrocytes in organoid culture , 2001 .

[5]  D. Salter,et al.  Integrin-interleukin-4 mechanotransduction pathways in human chondrocytes. , 2001, Clinical orthopaedics and related research.

[6]  P. Souza,et al.  Co-localization of integrins and matrix metalloproteinases in the extracellular matrix of chondrocyte cultures. , 2001, Histology and histopathology.

[7]  G. Davis,et al.  Regulation of the L-type Calcium Channel by α5β1 Integrin Requires Signaling between Focal Adhesion Proteins* , 2001, The Journal of Biological Chemistry.

[8]  D. Ingber,et al.  Mechanical behavior in living cells consistent with the tensegrity model , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[9]  G. Schulze-Tanzil,et al.  Inhibition of Mitogen-activated Protein Kinase Kinase Induces Apoptosis of Human Chondrocytes* , 2001, The Journal of Biological Chemistry.

[10]  M. Shakibaei,et al.  Expression of the urokinase-type plasminogen activator receptor in human articular chondrocytes: association with caveolin and β1-integrin , 2001, Histochemistry and Cell Biology.

[11]  N. Holstein-Rathlou,et al.  Integrin mobilizes intracellular Ca(2+) in renal vascular smooth muscle cells. , 2001, American journal of physiology. Cell physiology.

[12]  G. Nuki,et al.  Integrin and Mechanosensitive Ion Channel‐Dependent Tyrosine Phosphorylation of Focal Adhesion Proteins and β‐Catenin in Human Articular Chondrocytes After Mechanical Stimulation , 2000, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[13]  S. Guggino,et al.  Cardiac L‐Type Calcium Channel α1‐Subunit Is Increased by Cyclic Adenosine Monophosphate: Messenger RNA and Protein Expression in Intact Bone , 2000, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[14]  B. Attali,et al.  Extracellular K+ and Opening of Voltage-Gated Potassium Channels Activate T Cell Integrin Function , 2000, The Journal of experimental medicine.

[15]  S. Eom,et al.  Calreticulin couples calcium release and calcium influx in integrin-mediated calcium signaling. , 2000, Molecular biology of the cell.

[16]  A. Mobasheri,et al.  Na+, K+-ATPase Isozyme Diversity; Comparative Biochemistry and Physiological Implications of Novel Functional Interactions , 2000, Bioscience reports.

[17]  M. Shakibaei,et al.  Characterization of caveolins from human knee joint cartilage: expression of caveolin-1, -2, and -3 in chondrocytes and association with integrin β1 , 2000, Histochemistry and Cell Biology.

[18]  H. Lester,et al.  Expression of GIRK (Kir3.1/Kir3.4) channels in mouse fibroblast cells with and without β1 integrins , 2000, FEBS letters.

[19]  A. Mobasheri,et al.  Sodium transport systems in human chondrocytes. II. Expression of ENaC, Na+/K+/2Cl- cotransporter and Na+/H+ exchangers in healthy and arthritic chondrocytes. , 1999, Histology and histopathology.

[20]  P. Martín-Vasallo,et al.  Sodium transport systems in human chondrocytes. I. Morphological and functional expression of the Na+,K(+)-ATPase alpha and beta subunit isoforms in healthy and arthritic chondrocytes. , 1999, Histology and histopathology.

[21]  M. Shakibaei,et al.  Signal transduction by β1 integrin receptors in human chondrocytes in vitro: collaboration with the insulin-like growth factor-I receptor , 1999 .

[22]  C. Rubin,et al.  Mechanically induced calcium waves in articular chondrocytes are inhibited by gadolinium and amiloride , 1999, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[23]  D. Salter,et al.  Integrin-regulated Secretion of Interleukin 4: A Novel Pathway of Mechanotransduction in Human Articular Chondrocytes , 1999, The Journal of cell biology.

[24]  A. Mobasheri,et al.  Epithelial sodium channels in skeletal cells; a role in mechanotransduction? , 1999, Cell biology international.

[25]  A. Mobasheri,et al.  Brefeldin A influences the cell surface abundance and intracellular pools of low and high ouabain affinity Na+, K(+)-ATPase alpha subunit isoforms in articular chondrocytes. , 1999, Histology and histopathology.

[26]  H. Lester,et al.  Evidence for a Functional Interaction between Integrins and G Protein-activated Inward Rectifier K+ Channels* , 1998, The Journal of Biological Chemistry.

[27]  K. Svoboda.  Chondrocyte‐matrix attachment complexes mediate survival and differentiation , 1998, Microscopy research and technique.

[28]  G. Davis,et al.  Modulation of Calcium Current in Arteriolar Smooth Muscle by αvβ3 and α5β1 Integrin Ligands , 1998, The Journal of cell biology.

[29]  A. Mobasheri,et al.  Ion transport in chondrocytes: membrane transporters involved in intracellular ion homeostasis and the regulation of cell volume, free [Ca2+] and pH. , 1998, Histology and histopathology.

[30]  R. Florkiewicz,et al.  The Inhibition of Fibroblast Growth Factor-2 Export by Cardenolides Implies a Novel Function for the Catalytic Subunit of Na+,K+-ATPase* , 1998, The Journal of Biological Chemistry.

[31]  V. Trinkaus-Randall,et al.  Chondrocyte survival and differentiation in situ are integrin mediated , 1997, Developmental dynamics : an official publication of the American Association of Anatomists.

[32]  J. Robb,et al.  Electrophysiological Responses of Human Bone Cells to Mechanical Stimulation: Evidence for Specific Integrin Function in Mechanotransduction , 1997, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[33]  D. Ingber,et al.  Integrins, tensegrity, and mechanotransduction. , 1997, Gravitational and space biology bulletin : publication of the American Society for Gravitational and Space Biology.

[34]  A. Mobasheri,et al.  CHARACTERIZATION OF THE Na+K+‐ATPase IN ISOLATED BOVINE ARTICULAR CHONDROCYTES; MOLECULAR EVIDENCE FOR MULTIPLE α AND β ISOFORMS , 1997, Cell biology international.

[35]  K. Hruska,et al.  Reconstitution of stretch-activated cation channels by expression of the alpha-subunit of the epithelial sodium channel cloned from osteoblasts. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[36]  M. Yoshino,et al.  Voltage-gated ionic channels in cultured rabbit articular chondrocytes. , 1996, Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology.

[37]  M. Shakibaei,et al.  Changes in integrin expression during chondrogenesis in vitro: an immunomorphological study. , 1995, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[38]  J. Hell,et al.  Immunochemical identification and subcellular distribution of the alpha 1A subunits of brain calcium channels , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[39]  M. Shakibaei,et al.  Integrin expression on epiphyseal mouse chondrocytes in monolayer culture. , 1995, Histology and histopathology.

[40]  N. Farman,et al.  Cell-specific expression of epithelial sodium channel alpha, beta, and gamma subunits in aldosterone-responsive epithelia from the rat: localization by in situ hybridization and immunocytochemistry , 1994, The Journal of cell biology.

[41]  M. Shakibaei,et al.  Integrins in ageing cartilage tissue in vitro. , 1993, Histology and histopathology.

[42]  D. Ingber,et al.  Mechanotransduction across the cell surface and through the cytoskeleton , 1993 .

[43]  J. Hell,et al.  Biochemical properties and subcellular distribution of an N-type calcium hannel α1 subunit , 1992, Neuron.

[44]  W. Catterall,et al.  Identification of a phenylalkylamine binding region within the alpha 1 subunit of skeletal muscle Ca2+ channels. , 1990, Proceedings of the National Academy of Sciences of the United States of America.

[45]  H. Glossmann,et al.  Identification of the benzothiazepine-binding polypeptide of skeletal muscle calcium channels with (+)-cis-azidodiltiazem and anti-ligand antibodies. , 1990, The Journal of biological chemistry.

[46]  M. Schachner,et al.  Identification of a cDNA clone specific for the neural cell adhesion molecule AMOG , 1989, Journal of neuroscience research.

[47]  K. Takeyasu,et al.  Molecular characterization and expression of the (Na+ + K+)‐ATPase alpha‐subunit in Drosophila melanogaster. , 1989, The EMBO journal.

[48]  K. Takeyasu,et al.  Ouabain-sensitive (Na+ + K+)-ATPase activity expressed in mouse L cells by transfection with DNA encoding the alpha-subunit of an avian sodium pump. , 1988, The Journal of biological chemistry.

[49]  E Ruoslahti,et al.  New perspectives in cell adhesion: RGD and integrins. , 1987, Science.

[50]  M. Schachner,et al.  Biochemical and functional characterization of a novel neuron-glia adhesion molecule that is involved in neuronal migration , 1987, The Journal of cell biology.

[51]  Peter Müller,et al.  Relationship between cell shape and type of collagen synthesised as chondrocytes lose their cartilage phenotype in culture , 1977, Nature.

[52]  Barbara G. Pickard,et al.  Contemplating the plasmalemmal control center model+ , 2005, Protoplasma.

[53]  D. Salter,et al.  Effects of intermittent pressure-induced strain on the electrophysiology of cultured human chondrocytes: evidence for the presence of stretch-activated membrane ion channels. , 1996, Clinical science.

[54]  B. Zimmermann,et al.  Chondrogenesis, cartilage maturation and transformation of chondrocytes in organoid culture of mouse limb bud mesodermal cells , 1992 .