DEMONSTRATION OF ALKALINE-PHOSPHATASE PARTICIPATION IN THE MINERALIZATION OF OSTEOBLASTS BY ANTISENSE RNA APPROACH

MC3T3-E1 cells grown with ascorbic acid express sequentially osteoblas tic marker proteins such as alkaline phosphatase (ALPase) and then for m a mineralized extracellular matrix (ECM) as a consequence of osteobl astic differentiation. To explore the functional roles of ALPase in th e process of osteoblastic maturation, an inducible expression vector f or antisense ALPase RNA was constructed and stably transfected into MC 3T3-E1 cells. The expression of antisense ALPase RNA in the differenti ated MC3T3-E1 transfectants reduced markedly the ALPase activity, whic h resulted in a significant decrease in the deposition of minerals upo n prolonged culture. These findings demonstrated directly that ALPase participated in the mineralization of ECM. (C) 1996 Academic Press Lim ited