Connective tissue growth factor mediate ERK1/2 and focal adhesion kinase activation through integrin αVβ3 signal transduction. Figure 6A shows the immnoprecipitation and immunoblotting analysis. The cell extracts of osteoclasts stimulated with recombinant CTGF (10 or 50 ng/ml) at 60 minutes were precipitated using anti-integrin αVβ3 antibody and subsequently blotted with anti- phosphorylated ERK1/ERK2, conventional ERK1/ERK2, and integrin αVβ3 antibodies respectively. The phosphorylated ERK1/ERK2 was recruited with integrin αVβ3 by CTGF stimulation. Figure 6B shows the immunoblotting analysis using anti- phosphorylated FAK, conventional FAK, and β-actin antibodies in the osteoclasts extracts treated with CTGF (10 ng/ml) at 5, 15, 60, and 120 minutes in the presence or absence of anti-CTGF antibody (1 μg/ml). CTGF stimulation resulted in phosphorylation of FAK from 60 minutes and this effect was neutralized by anti-CTGF antibody suggesting activation of signal transduction pathways through integrin αVβ3.