Convergence of alpha(v)beta(3) integrin- and macrophage colony stimulating factor-mediated signals on phospholipase Cgamma in prefusion osteoclasts.
The macrophage colony stimulating factor (M-CSF) and alpha(v)beta(3) integrins play critical roles in osteoclast function. This study examines M-CSF- and adhesion-induced signaling in prefusion osteoclasts (pOCs) derived from Src-deficient and wild-type mice. Src-deficient cells attach to but do not spread on vitronectin (Vn)-coated surfaces and, contrary to wild-type cells, their adhesion does not lead to tyrosine phosphorylation of molecules activated by adhesion, including PYK2, p130(Cas), paxillin, and PLC-gamma. However, in response to M-CSF, Src(-/-) pOCs spread and migrate on Vn in an alpha(v)beta(3)-dependent manner. Involvement of PLC-gamma activation is suggested by using a PLC inhibitor, U73122, which blocks both adhesion- and M-CSF-mediated cell spreading. Furthermore, in Src(-/-) pOCs M-CSF, together with filamentous actin, causes recruitment of beta(3) integrin and PLC-gamma to adhesion contacts and induces stable association of beta(3) integrin with PLC-gamma, phosphatidylinositol 3-kinase, and PYK2. Moreover, direct interaction of PYK2 and PLC-gamma can be induced by either adhesion or M-CSF, suggesting that this interaction may enable the formation of integrin-associated complexes. Furthermore, this study suggests that in pOCs PLC-gamma is a common downstream mediator for adhesion and growth factor signals. M-CSF-initiated signaling modulates the alpha(v)beta(3) integrin-mediated cytoskeletal reorganization in prefusion osteoclasts in the absence of c-Src, possibly via PLC-gamma.
Department of Bone Biology and Osteoporosis Research, Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
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Nakamura
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Lipfert
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Rodan
Le T  Duong
D000730:Androstadienes / Q000494:pharmacology; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D002459:Cell Fusion; D002478:Cells, Cultured; D050719:Crk-Associated Substrate Protein; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D051418:Focal Adhesion Kinase 2; D007527:Isoenzymes / Q000378:metabolism*; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D051419:Paxillin; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051966:Phospholipase C gamma; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011506:Proteins; D011760:Pyrrolidinones / Q000494:pharmacology; D019030:Receptors, Vitronectin / Q000502:physiology*; D050717:Retinoblastoma-Like Protein p130; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013154:Spleen / Q000166:cytology; D010738:Type C Phospholipases / Q000378:metabolism*; D019096:Vitronectin; D000077191:Wortmannin; D019061:src-Family Kinases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism
D000730:Androstadienes; C493842:Bcar1 protein, mouse; D050719:Crk-Associated Substrate Protein; D003598:Cytoskeletal Proteins; D004791:Enzyme Inhibitors; D004963:Estrenes; D007527:Isoenzymes; D051419:Paxillin; D010750:Phosphoproteins; D011506:Proteins; C496062:Pxn protein, mouse; D011760:Pyrrolidinones; D019030:Receptors, Vitronectin; D050717:Retinoblastoma-Like Protein p130; D019096:Vitronectin; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D016173:Macrophage Colony-Stimulating Factor; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; D051418:Focal Adhesion Kinase 2; C496053:Ptk2b protein, mouse; D019061:src-Family Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D000077191:Wortmannin