Objective   To observe mitotic checkpoint function of human embryo lung fibroblasts (HELF) after transfected with hBub1 gene expression vectors, including pBI-GF P-hBub1* WT, V429 and V400.

  Methods   Lipofectamine^TM was used to co-transfect pBI-GFP-hBub1 and pTet-On into HELF cells, and the flow cytometry was used to analyze the cycle profile and the mitotic checkpoint function of successfully transfected cells(with GFP expression)and non-successfully transfected cells(without GFP expression).

  Results   After HELF cells were transfected with the vectors, some cells could express GFP, which was the reporter protein of the vectors. After treatment with colchicines for 12 hours, the cells transfected with wild type hBub1 vector have normal mitotic checkpoint function, the ratio of cells arrested at G₂/M phase were 44.27%.Among the cells successfully transfected with mutanthBub1 V429 or V400, the ratio of cells arrested at G₂/M phase were 23.13% and 20.87% respectively, which meant that the mitotic checkpoint function of cells decreased.

  Conclusion   Transfection and expression of mutant mitotic checkpoint gene hBub1 induced the decrease of the HEL F cell mitotic checkpoint function.