title: Osteoprotegerin disrupts peripheral adhesive structures of osteoclasts by modulating Pyk2 and Src activities.
abstract: Osteoprotegerin has previously been shown to modulate bone mass by blocking osteoclast maturation and function. The detailed mechanisms of osteoprotegerin-induced disassembly of podosomes, disruption of adhesive structures and modulation of adhesion-related proteins in osteoclasts, however, are not well characterized. In this study, tartrate-resistant acidic phosphatase staining demonstrated that osteoprotegerin inhibited differentiation of osteoclasts. The use of scanning electron microscopy, real-time cell monitoring and confocal microscopy indicated that osteoclasts responded in a time and dose-dependent manner to osteoprotegerin treatments with retraction of peripheral adhesive structures and detachment from the extracellular substrate. Combined imaging and Western blot studies showed that osteoprotegerin induced dephosphorylation of Tyr 402 in Pyk2 and decreased its labeling in peripheral adhesion regions. osteoprotegerin induced increased intracellular labeling of Tyr 402 in Pyk2, Tyr 416 in Src, increased dephosphorylation of Tyr 527 in Src, and increased Pyk2/Src association in the central region of osteoclasts. This evidence suggests that Src may function as an adaptor protein that competes for Pyk2 and relocates it from the peripheral adhesive zone to the central region of osteoclasts in response to osteoprotegerin treatment. Osteoprotegerin may induce podosome reassembly and peripheral adhesive structure detachment by modulating phosphorylation of Pyk2 and Src and their intracellular distribution in osteoclasts.
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhao
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Xuezhong
authors.initials: X
authors.lastname: Liu
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zou
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Nannan
authors.initials: N
authors.lastname: Dai
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Lulian
authors.initials: L
authors.lastname: Yao
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Gao
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Jianhong
authors.initials: J
authors.lastname: Gu
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Jianchun
authors.initials: J
authors.lastname: Bian
authors.affiliation: a College of Veterinary Medicine, Yangzhou University , Yangzhou , Jiangsu , P.R. China.|b Jiangsu Co-innovation Center for Prevention and Control of Important, Animal Infectious Diseases and Zoonoses , Yangzhou , Jiangsu , P.R. China.
authors.forename: Zongping
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D051418:Focal Adhesion Kinase 2 / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D051379:Mice; D010010:Osteoclasts / Q000166:cytology / Q000648:ultrastructure; D053244:Osteoprotegerin / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D010768:Phosphoserine / Q000378:metabolism; D000069261:Podosomes / Q000187:drug effects / Q000378:metabolism; D000067996:RAW 264.7 Cells; D019061:src-Family Kinases / Q000378:metabolism*
chemical_list: D053244:Osteoprotegerin; D010768:Phosphoserine; D051418:Focal Adhesion Kinase 2; D019061:src-Family Kinases
keywords: Pyk2; osteoclast; osteoprotegerin; podosome; src