Construction and application of DPPª²rhBMPª²4m fusion protein expression vector

    WANG Li, CHEN Suª²Min, CHEN Nanª²Chun, ZHANG Xiaoª²Nan, ZHAO Weiª²Qin, HUANG Yong, WANG Tao, GUAN Luª²Yuan

    Department of Biochemistry and Molecular Biology, School of Basic Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To construct a E.coli fusion protein expression vector from which tag protein can be removed easily. METHODS: The codons of Aspª²Proª²Pro were added to 5¬ðª²teminal of rhBMPª²4m (recombination human bone morphogenetic protein 4 mature peptide)gene by PCR. The DPPª² rhBMPª²4m coding sequence was cloned into E.coli BL21 and induced to express with IPTG. The expressed fusion protein (DPPª² rhBMPª²4m) was analyzed by SDSª²PAGE and Western Blot. After the 6His tag protein was removed by formic acid, the purified PPª² rhBMPª²4m was added to C2C12 cells to observe its biological activity. RESULTS: The DNA sequencing showed that the sequence of the fusion protein expression vector constructed in this study was exactly consistent with the one predicted. The fusion protein occupied 37% of the total bacteria protein, while the purity of the target protein(rhBMPª²4m) reached 97% after affinity chromatography. And the protein could specifically react with antiserum and showed a good biological activity in C2C12 cells. CONCLUSION: The pRSETª²DPPª²rhBMPª²4m vector is successfully constructed for the purification of interest protein. ......