[Construction of recombinant expression vector of IL-24 gene and prokaryotic expression].

AIM: To construct a recombinant expression vector of human IL-24 gene and express it in E. coli. METHODS: The hIL-24 cDNA fragment was amplified from plasmid TRAP-hIL-24 by PCR, then cloned into the prokaryotic vector pGEX-KG, and expressed as a fusion protein in E. coli. The expressed IL-24-GST fusion protein was purified via GST-Sepharose 4B Column and identified by SDS-PAGE and Western blot. The bioactivity of GST-IL-24 fusion protein was measured by MTT assay. RESULTS: Restriction enzyme digestion analysis showed that the recombinant prokaryotic expression vector pGEX-KG-IL-24 was successfully constructed and expressed in E. coli. The relative molecular mass (M(r)) of the expression product was identical with the predicted value. The proliferation of THP-1 cells was inhibited by GST-IL-24 fusion protein. CONCLUSION: The recombinant expression vector pGEX-KG-IL-24 has been constructed successfully and expressed as a bioactive fusion protein in E. coli BL21 (BlysS), which is helpful for the further study of the biological function of IL-24.