目的:构建哺乳类动物雷帕霉素靶蛋白(mTOR)的反义RNA真核表达载体,观察其对血管平滑肌细胞(VSNC)功能的影响。方法:提取人VSMC总RNA,反转录-聚合酶链反应(RT-PCR)扩增mTOR基因cDNA序列,经pGEM-T载体克隆后双酶切,将cDNA序列反向插入绿色荧光蛋白表达载体pEGP-C1,构建mTOR基因反义RNA真核表达载体。转染VSMC,采用Western blot法检验反义表达载体对mTOR蛋白表达的影响,流式细胞仪检测细胞周期的变化。结果:经RT-PCR获得664bp产物,T载体克隆后,经DNA测序,确定该片段为mTOR基因cDNA,进而构建反义RNA真核表达载体pEGFP-C1-mTOR,测序证明序列正确后转染VSMC,证实其能够显著抑制mTOR蛋白产物表达,VSMC的分裂、增殖过程受阻。结论:已经成功构建mTOR基因的反义RNA真核表达载体。
Objective: To construct pEGFP-C1-mTOR vector, an eukaryotic expression plasmid of mTOR gene antisense RNA, and to study the effect of this vector on the function of vascular smooth muscle cells (VSMC). Methods: The conservative region of mTOR gene was amplified by revcrse transcriptase polymerase chain reaction (RT-PCR) after total RNA was extracted from human VSMC and then cloned into pGEM-T vector. After the recombinant plasmid was certified by DNA sequencing, the conservative region of mTOR gene was inserted into pEGFP-C1 vector reversedly, and pEGFP-C1- mTOR vector was constructed. The efficiency of antisense inhibition was verified by Western blotting after the transfection of VSMC. The cell cycle was determined by flow cytometry. Results: A 664- bp fragment including conservative region of roTOR gene was obtained by RT-PCR. After cloned by pGEM-T vector and certified by DNA sequencing, pEGP-C1-mTOR vector was successfully constructed by recombinant DNA technology. Additionally, pEGFP- C1- mTOR vector could efficiently decrease mTOR protein expression level by 82% 72 hours after the transfection of VSMC. The cell cycle was stunned. Conclusion: The efficient expression vector of roTOR gene antisense RNA, pEGFP-C1- mTOR , has been constructed successfully.