<正> Objective: To explore the possibility of the transfection of MyoD gene induced bone marrow mesenchymal stem cells （ MSCs） to differentiate into myoblasts in vitro. Methods: The eukaryotic expression plasmid vector pIRES2-EGFP-MyoD was transfected into MSCs with lipotransfection method

and the positive cells were selected by G418; The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified

purified product was identified by sequencing; The reporter gene enhanced green fluorescence protein （ EFGP） was observed in the transfected cells under a fluorescent and a laser confocal microscopes; Immunohistochemical methods was used to examine the expressions of MyoD

myogenin

myosin

myoglobin and desmin in the differentiated cells. The ultrastructure changes of the cells before and after transfection were observed with electron microscopy. Results: The expression of MyoD was detected in the transfected MSCs with RT-PCR and the amplified

purified product was as same in sequence a