RESUMO
Apoptosis, a genetically encoded process of cellular suicide, comprises an intrinsic cellular defence against tumorigenesis. bak(for bcl-2 homologous antagonist/killer) is a new apoptosis-inducing gene found recently, which is identified in all tissues examined. Initial work of Farrow, Chittenden and Klefer indicated that bak plays an important role in apoptosis. Successive work of others suggests inactivity of Bak always accompanies the development of tumor cells. In this work, a shuttle vector harboring bak gene, pCA13-bak, was constructed and used to cotransfect into the cell line 293 together with a recombinant plasmid, pBHG11, containing most of adenovirus genome. A mutant adenovirus(delete E1, E3 region)carring bak, Ad-bak, was obtained, and purified. Dot blot identified the construction of recombinant virus was successful. HeLa cells were infected by this virus. Some manners were used to identify the changes of HeLa cells including Annexin V-FITC staining which made the reversed PS observed directly, microscope observation and others. The characteristic morphology of apoptotic cells was due to Ad-bak. The experiment suggests that bak is a strong apoptosis-inducing gene, and a potential gene which could be used in gene therapy on tumor.