Abstract: A synthesized double-stranded oligomeric nucleotide encoding 11-amino acid TAT protein transduction domain3 was inserted into pET28a vector after 6 histidind coding sequence,LacZ gene from pcDNA4/Myc-His/LacZ was digested by EcoRⅠand HindⅢ,then cloned into pET28a-TAT.The highly expressed TAT-β-galactosidase was purified by affinity chromatography.TAT-β-Gal fusion protein can across vascular smooth muscle cells in vitro.This result open new possibility for direcy delivery of protein into tissues for therapy.