Abstract: Objective To study the effect of lentivirus modification of human activating transcriptional factor4(ATF4) gene on cell apoptosis and cycle in C2C12 cells. Methods The recombinant ATF4 lentivirus were produced in 293T cells following to co-transfection between pWPT-GFP-ATF4 and the lentivirus packaging plasmids. The effect of recombinant lentivirus ATF4 on proliferation and apoptosis in C2C12 cells was detected by flow cytometry(FCM). Western blotting analysis was used to examine the expression of apoptosis-ralated proteins. Results The recombinant lentivirus ATF4 was successfully constructed. FCM analysis showed that under BMP2-induced differentiation condion,the ratio of S phase C2C12 cells in the BMP2+LV-ATF4 group(14.89%) was significantly lower than those in BMP2+LV-GFP group(30.64%)(P＜0.05);The apoptosis rate in the BMP2+LV-ATF4 group(31.06%) was significantly higher than those in the BMP2+LV-GFP group(11.39%)(P＜0.05).Western blotting analysis showed that the expression of Cleaved Caspase-3,Chop and p-JNK was consistent with results of FCM. Conclusion Under BMP2-induced differentiation condition, LV-ATF4 can suppress the cell proliferation and promote the cell apoptosis in C2C12 cells.

Key words: ATF4, lentivirus, osteogenic differentiation, cell proliferation, cell apoptosis