RANKL-induced DC-STAMP Is Essential for Osteoclastogenesis

Kukita et al [1] demonstrated for the first time that DC-STAMP plays an important role in the osteoclastogenesis. DC-STAMP and DC-STAMP{Delta}T7 have similar activities, indicating that the seven-transmembrane domain and the intracellular COOH terminus may not be essential for its function. But DC-STAMP and DC-STAMP{Delta}T7 may behave differently upon binding with putative DC-STAMP ligand. Important evident: DC-STAMP/DC-STAMP{Delta}T7 expression induced by RANKL and other osteoclastogenic stimulations was well ahead of TRAP and Cathepsin K expression; Targeted inhibition of DC-STAMP by small interfering RNAs and specific antibody markedly suppressed the formation of multinucleated osteoclast-like cells; Overexpression of DC-STAMP enhanced osteoclastogenesis in the presence of RANKL. Furthermore, DC-STAMP directly induced the expression of the osteoclast marker tartrate-resistant acid phosphatase (TRAP). Unrelated comment to this article: What does TRAP do in osteoclasts?

1. Kukita T, Wada N, Kukita A, Kakimoto T, Sandra F, Toh K, Nagata K, Iijima T, Horiuchi M, Matsusaki H, Hieshima K, Yoshie O, Nomiyama H (2004) RANKL-induced DC-STAMP is essential for osteoclastogenesis. J Exp Med 200:941-946