Abstract: Objective To construct the adenoviml shuttle vector,the pshuttle-Egrl-hSmac containing radation-sensitive Egrl promoter,and the second mitochondria-derived activator of caspases (Smac) gene.Methods The Smac gene was amplified by reverse transcriptase-polymemse chain reaction (RT-PCR) from fetal liver,and the Egrl promoterwas cut down from plasmid pMD19T-Egrl.Then the adenovirus shuttle vector pshuttle-Egrl-hSmac was constmcted by the gene recombinant technique.Results The sequence of amplified Smac genewas in concordancewith thatpublished on GenBank,indicating that the Smac gene was cloned successfully.Furtheanore,the recombinantplasmidpshuttle-Egrl-Smacwas identified by endonuclease digestion,which could be digested into two or three fragements of EcoRⅠ，SmaⅠ and BamHⅠ，respectively The length of them were 2621 and 5137 base pairs for EcoRⅠ，1437,2282 and 4039 base pairs for SmaⅠ，3303 and 4455 base pairs for BamHⅠ.The results of the identification confirmed that the recombinant plasmid pshuttle-Egrl-Smac was constructed successfully.Conclusion The human Smac gene was cloned and the recom binant plasmid pshuttle-Egrl-Smac was constructed successfully