Aim: To investigate the effects of bone morphogenetic protein-7 (BMP7)-expressing recombinant adeno-associated virus (AAV) vector on the differentiation of C2C12 cells. Methods: AAV-BMP7 was packaged by infecting the stable cell clone BHK-21 (integrated with recombinant AAV vector plasmid pSNAV-BMP7) with recombinant herpes simplex virus type 1, which expresses AAV-2 Rep and Cap and possesses AAV packaging functions. Following infection with AAV-BMP7 at multiplicities of infection of lx 10~5 vector genomes per cell and subse-quent culture, C2C12 cells were assessed qualitatively for BMP7 production, alka-line phosphatase activity, osteocalcin production and Cbfal and MyoD expression. Results: C2C12 cells transduced with AAV-BMP7 could produce BMP7 protein until d 28. Alkaline phosphatase in the cultured C2C12 cell lysate was elevated. Secreted osteocalcin in the culture medium was detectable at d 12 and Cbfal mRNA expression level was upregulated, coinciding with downregulation of MyoD in a temporal manner. Conclusion: The present in vitro study demonstrated that AAV-BMP7 could infect and efficiently convert C2C12 cells from myoblasts into osteoblast lineage cells. Aim: To investigate the effects of bone morphogenetic protein-7 (BMP7) -expressing recombinant adeno-associated virus (AAV) vector on the differentiation of C2C12 cells. Methods: AAV-BMP7 was packaged by infecting the stable cell clone BHK-21 integrated with recombinant AAV plasmid pSNAV-BMP7) with recombinant herpes simplex virus type 1, which expresses AAV-2 Rep and Cap and possesses AAV packaging functions. Following infection with AAV-BMP7 at multiplicities of infection of lx 10-5 vector genomes per cell and subse-quent culture, C2C12 cells were assessed qualitatively for BMP7 production, alka-line phosphatase activity, osteocalcin production and Cbfal and MyoD expression Results:. C2C12 cells transduced with AAV-BMP7 could produce BMP7 protein until d 28. Alkaline phosphatase in The cultured C2C12 cell lysate was elevated. Secreted osteocalcin in the culture medium was detectable at d 12 and Cbfal mRNA expression level was upregulated, coinciding with downregulation of MyoD in a temporal manner. Conclusion: The present in vitro study demonstrated that AAV-BMP7 could infect andfficient convert C2C12 cells from myoblasts into osteoblast lineage cells.