Prokaryotic expression,purification and identification of human prostate stem cell antigen
- VernacularTitle:人前列腺干细胞抗原的原核表达、纯化及鉴定
- Author:
Jie REN
;
Jiangping GAO
;
Jinqi YAN
;
Le JIANG
;
Jiyun YU
- Publication Type:Journal Article
- Keywords:
PSCA protein,human;
plasmids;
recombinant fusion proteins
- From:
Medical Journal of Chinese People's Liberation Army
2001;0(08):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To construct the prokaryotic expression plasmid of human prostate stem cell antigen (PSCA),to induce the expression of GST-PSCA fusion protein in E. coli BL21,and to identify the purified recombinant fusion protein. Methods The fragment of PSCA gene was amplified by PCR,and then cloned into the pGEM-T Easy vector. The transitional plasmid Teasy-PSCA was identified by DNA sequencing. The PSCA gene was digested from the plasmid Teasy-PSCA by restrictive enzyme BamH I and Sal I,and then inserted into the pET42a vector which contains a glutathione s-transterase (GST) tag. Following the double restriction enzyme digestion,the recombinant plasmid pET42a-PSCA was obtained and transformed into E. coli BL21 (DE3). The expression of GST-PSCA fusion protein was induced with IPTG. The recombinant fusion protein was purified by passing over a Glutathione Sepharose 4B column,and was identified by SDS-PAGE and Western blotting. Results The length of amplified PSCA gene fragment was consistent with that expected,and the sequence was correct as exemplified by the PSCA gene reported in GenBank. The result of enzyme digestion indicated that the prokaryotic expression plasmid pET42a-PSCA was successfully constructed. After transformation with pET42a-PSCA and induction with IPTG,the recombinant target protein of about 43kD was obtained. The GST-PSCA fusion protein was correctly identified by SDS-PAGE and Western blotting. Conclusions The prokaryotic expression plasmid of human PSCA gene has been successfully constructed. The GST-PSCA fusion protein may express and be purified in E. coli BL21,and it lays a foundation for further study on the anti-prostate cancer gene vaccine.
