Expression of human soluble apoptosis 2 ligand in Pichia pastoris

Objective: To investigate the soluble part of tumor necrosis factor related apoptosis inducing ligand (TRAIL) expressed in Pichia pastoris . Methods: RT PCR was used to produce the TRAIL soluble molecule which encoded 114 281 amino acid. This molecule was inserted into Pichia pastoris vector pIC 3.5. The recombinant vector was transformed into GS115 by LiCl, and the expression was induced by methanol for 5 d. The expression was identified by SDS PAGE and Western blotting. The expressed products were cytotoxicity to L929 cell line. Results: SDS PAGE analysis indicated that a new protein band was found corresponding to relative molecular mass 1.96×10 4, which made up 50% of the total proteins. The anti TRAIL polyclonal body could recognize the recombinant protein from Pichia pastoris GS115. The cytotoxicity to L929 cells of the recombinant product was higher than that from E. Coli . DNA ladder was induced by this recombinant TRAIL in some tumor cell lines. Its advanced structure might be valid in yeast. Conclusion: The soluble molecule of TRAIL is expressed in Pichia pastoris. [