SH2域S、HP2 cDNA的克隆鉴定和在大肠杆菌中的表达及其与CagA的相互作用

Cloning, characterization and expression in E.coli of cDNA of SH2 domain and SHP2 and their interaction with CagA

目的研究SH2(Src同源体2)域和SHP2(含2个SH2域的蛋白酪氨酸磷酸酶)蛋白的基因克隆和表达。方法根据GeneBank中SH2和SHP2的基因序列设计引物,以PCR法扩增出SH2和SHP2基因,将其插入pQE30质粒中,转化进E.coli感受态细胞中,筛选阳性克隆并研究其表达。结果所克隆的目的基因片断经PCR法鉴定和序列分析证明正确。结论已成功地扩增SH2和SHP2基因并克隆到pQE30载体上,转化大肠杆菌菌株有表达,并探讨其与CagA(细胞毒性关联的基因A抗原)的相互作用及导致胃细胞癌变的原因。

OBJECTIVE To research the cloning and expression of SH2（src homology 2） domain and SHP2（SH2 - protein tyrosine phosphatase）. METHODS In term of the SH2 and SHP2 sequences in Gene Bank their primers were designed and synthesized. SH2 and SHP2 gene were amplified by PCR. Then the genes were inserted into pQE30 plasmid. The plasmids were transformed into E. coli competent cells and the positive clones were screened. The expression of SH2 and SHP2 in E. coli were investigated. RESULTS The target gene segments were verified by PCR and sequencing. CONCLUSION SH2 domain and SHP2 cDNA have been successfully cloned into pQE30 and expressed in E. coli. Moreover we probe the interaction mechanism of SHP2 and CagA（ cytotoxin associated gene A antigen）, which may initiate oncogenesis in gastric epithelia.