Cloning, Expression and Bioactivity of TNF-related Apoptosis Inducing Ligand(TRAIL)

TNF related apoptosis inducing ligand(TRAIL) can induce specific apoptosis of cancer cells. In order to obtain recombinant TRAIL through genetic engineering, the cDNA coding soluble fragment of TRAIL(sTRAIL) was amplified from human placental cDNA library by PCR method and cloned into pGEM 3Zf(-) vector to analyze the sequence. The result showed that DNA sequence of cloned human sTRAIL was the same as that reported previously. To express sTRAIL,the cDNA was cloned into expression vector pBV220 which was then transformed into E.coli DH5α host bacteria. The recombinant protein was expressed with the yield of 20% total bacterial protein. SDS PAGE and Western blot analysis indicated that the molecular weight of recombinant protein was about 18 5 kD and could react specifically with anti TRAIL monoantibody. The recombinant protein was purified and could significantly induce apoptosis of L929 cells.