Cloning of mature peptide cDNA gene of human bone morphogenetic protein 4 and its expression in Escherichia coli

    QIN Yun1,2, CHEN Suª²Min1, GUAN Luª²Yuan1, CHEN Nanª²Chun1, ZHANG Liª²Fan2

    1Department of Biochemistry and Molecular Biology, School of Basic Medicine, 2Department of Aerospace Physiology, School of Aerospace Medicine, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To clone the cDNA coding for human bone morphogenetic protein 4 mature peptide (hBMP4m) and to express the peptide in Escherichia coli. METHODS: Total RNA from human placenta was extracted and the cDNA coding for hBMP4m was obtained by RTª²PCR using placenta total mRNA as the template. The cDNA was cloned into expression vector pDH2 and transformed to Escherichia coli DH5¦Á. After the sequence of the inserted gene was confirmed as designed, pDH2ª²hBMP4m/DH5¦Á was induced at 42¡æ. RESULTS: Mature peptide cDNA coding for hBMP4m was obtained and was proven to have the sequence as designed. The expression vector pDH2ª²hBMP4m was constructed. After the vector was transformed into DH5¦Á and induced at 42¡æ, the target protein, hBMP4m, accounted for 41.5% of the total bacterial protein. CONCLUSION: We have successfully cloned the cDNA coding for hBMP4m and constructed the vector capable of expressing hBMP4m at a high level. ......