Cloning, expression and characterization of human heparanse Cª²terminal subunit protein in E. coli

    LI Yanª²Jie, LI Jiª²Xue, LING Yan, TANG Guoª²Ying, LIN Yanª²Li, ZHU Houª²Chu

    1Medical Experimental Center, Zhengzhou University, Zhengzhou 450052, China, 2Institute of Biology Engineering, Academy of Military Medical Sciences, Beijing 100071, China

    ¡¾Abstract¡¿AIM: To construct the expression vector for heparanase (HPA) Cª²terminal subunit and obtain enough protein for further study. METHODS: Full encoding gene of heparanase protein was isolated from the human platenta cDNA library and its expressing vector pGEXª²2TKª²50 ku HPA was constructed by cloning its Cª²terminal subunit gene into the pGEXª²2TK vector. After transformed by the expression vector, E.coli BL21 (PlyS, DE3) was induced to express the target protein. RESULTS: E.coli BL21 (PlyS, DE3, pGEXª²2TKª²50 ku HPA) began to express the target protein fused by GST protein and Cª²terminal subunit protein after 1 h induction and kept producing it until 3 h after induction when the target protein reached a maximum. No degradation of produced protein was observed in the hetero E.coli cells. The target protein was expressed mostly in inclusive bodies. When growing at lower temperature, some fused protein was detected soluble in cell lysis. CONCLUSION: The Cª²terminal subunit protein of heparanase fused with GST protein has been successfully expressed in E.coli BL21 (PlyS, DE3). The protein may be a good antigen in preparing the antibody for heparanase and in further study of its function. ......