基质金属蛋白酶抑制因子-1 小干扰RNA载体构建及对肝星状细胞沉默效应的研究

目的构建TIMP-1小干扰RNA(siRNA)真核表达载体并观察其对肝星状细胞株TIMP-1 mRNA表达的作用。方法根据siRNA设计原则,在TIMP-1 mRNA序列中选择2个特异性靶序列(447～465 nt、552～540 nt)及1条无关对照序列,体外合成对应发卡样DNA片段,将其克隆入pGEM-T连接载体,BamH I和Xho I分别双酶切pGEM-T及表达载体pRNAT-U6.2,胶回收粘末端将特异序列定向亚克隆构建TIMP-1 pRNAT-U6.2/siRNA载体,用脂质体包裹转染入T6细胞,采用RT-PCR检测TIMP-1 mRNA表达水平的变化。结果所构建的TIMP-1 pRNAT- U6.2/siRNA载体,经酶切鉴定与测序,结果显示特定位点靶序列与设计序列完全一致;转染T6细胞后,TIMP-1 mRNA表达明显降低。结论成功构建TIMP-1 siRNA载体TIMP-1 pRNAT U6.2/siRNA,转染T6细胞可以有效抑制TIMP-1 mRNA的表达。

Construction and identification of matrix metalloproteinal inhibitor-1 siXNA eukaryotic expression vectors

Objective To construct TIMP-1 siRNA eukaryotic expression vectors and evaluate their effect on TIMP-1 mRNA expression in hepatic stellate cells. Methods The combinant lone DNA with cutting sites of BamH I and Xho I enzyme according to the sequences of 447-465, 552-540 TIMP-1 of rats and nonspecific sequence were selected and cloned to pGEM-T vector and sub-cloned to pRNAT-U6.2. They were then identified by double enzyme digestion analysis and DNA sequencing. Three plasmids were trans-fected into T6 separately through an oligofectamine package. TIMP-1 mRNA expression was evaluated by RT-PCR. Results Targeting sequences of TIMP-1 siRNA eukaryotic expression vectors were correct. TTMP-1 mRNA expression was significantly reduced by transfecting them into the T6. Conclusion We successfully constructed two TIMP-1 siRNA eukaryotic expression vectors and the transfected cells can significantly suppress the TIMP-1 expression.