The cloning, expression and refolding of TNF-related apoptosis inducing ligand

Objective: To clone human TRAIL(TNF related apoptosis inducing ligand) gene into E.coli expression vector to get active TRAIL protein after refolding and purification. Methods: The human TRAIL gene was amplified from the human placenta cDNA library, and cloned into prokaryotic expression vector pET11a after being sequenced. The plasmid was transformed into E.coli BL21 (DE3), followed by expression, refolding and purification. The protein activity was measured by flow cytometry. Results: The TRAIL 1 from 418 933 of the cDNA (the coding region of TRAIL was 111 281) and TRAIL 2 from 88 933 of the cDNA (coding for full length TRAIL) were obtained. The prokaryotic and eukaryotic expression vectors were pET11 TRAIL1 and pLNCX TRAIL2 respectively. The former was transformed and expressed in E.coli BL21 (DE3), then the refolded and purified protein was obtained. The apoptosis of human leukemia cell line Jurkat had been successfully induced by this TRAIL protein. Conclusion: The human TRAIL gene was amplified from the human placenta cDNA library, and after expression in E.coli , refolding and purification, the active TRAIL protein was obtained.