ObjectiveTo investigate the significance of Bad mRNA induced by coxsackievirus B3 (CVB3).MethodsAfter HeLa cells infected by CVB3,the cellular morphology at different times of infection was observed under the inverted microscope,and Bad mRNA expression was determined by RTPCR.The difference of Bad mRNA expression was compared with ttest.ResultsThe cellular morphology in control group was not obviously changed at different time points,but the cytopathic effect (CPE) in viral groups was significantly gradually changed at the infection time,which was most obvious at 24h.At the meantime,the expression of Bad mRNA in control group was not significantly different at different infection time points(P>0.05),which was the same in the viral groups.But Bad mRNA expression in CVB3 group(0.61±0.06) was decreased compared with the control (0.76±0.06)(t=-3.445,P<0.05) at 24h.However,there was no significance at other infection points such as 3h,6h,9h and 12h.ConclusionsAs the proapoptotic gene of Bad mRNA,plays an important role in the CVB3 infection which induces the apoptosis of Hela cells.