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Skeletal remodeling via coupling of bone formation and resorption is a dynamically regulated process, involving intercellular communication between osteoblasts and osteoclasts. The remodeling process consists of: a) Activation: Pre-osteoclasts are stimulated and differentiate into osteoclasts under the influence of cytokines and other growth factors. b) Osteoclastic resorption: Osteoclasts digest mineralized matrix of bone. c) Reversal: End of resorption; and d) Bone formation: Preosteoblast migration and differentiation into osteoblasts followed by osteoid formation and mineralization. The equilibrium between bone formation and bone resorption at sites of bone remodeling is controlled by paracrine and autocrine growth factors including BMPs, transforming growth factor-β (TGF-β), Insulin-like growth factor (IGF-1), heparin binding fibroblast growth factor (FGF), platelet derived growth factor (PDGF), receptor activator of NF-kappa B ligand (RANK-L), osteoprotegrin (OPG). Understanding the paracrine “cross-talk” is critical in devising novel therapeutic approaches for diseases of unbalanced bone resoprtion (eg osteoporosis), or bone fromation (eg Paget’s disease). BMPs are promoters of osteoblastic differentiation and bone formation. In this study, we report the localization and expression of BMPs in osteoclasts generated from co-cultures of mouse calvarial osteoblasts and bone marrow cells from mouse femur and tibia using immunohistochemistry, in situ hybridization, and western blotting in lysates of osteoclasts. Our working hypothesis is that BMPs expressed by osteoclasts recruit osteoblasts to a bone resorption site, thus initiating the anabolic …