端粒酶RNA基因在白细胞中表达的研究

用RT－PCR的方法钓取端粒酶RNA（hTR）基因的cDNA，将hTR基因克隆到逆转录病毒载体（pLNCX）构建哺乳动物细胞表达质粒，然后经脂质体介导转染人体正常的外周血白细胞中表达。结果表明端粒酶RNA基因的表达，不能激活或重建白细胞的端粒酶活性，流式细胞技术分析结果显示，外源hTR基因的表达不能延长白细胞的寿命，反而抑制白细胞的增殖并促进其凋亡，这可能是因为外源hTR基因的表达一定程度上阻碍了细胞内端粒酶RNA同端粒酶催化亚基的结合，同时也阻碍了端粒酶RNA模板区与端粒DNA之间的结合，从而影响端粒酶活性，抑制了细胞的增殖。

Study on the Expression of Telomerase RNA in Leukocyte

Total cDNA of human telomerase RNA(hTR) gene was cloned by means of RT-PCR and inverted into retroviral vector (pLNCX) to construct the mammalian cell expression plasmid.Then, by using lipofectin-mediated DNA transfection, the obtained expression plasmid was successfully transfected into human normal peripheral blood leukocyte. All data suggested that expression of transfected exogenous hTR gene can not reconstitute telomerase activity. Flow cytometry analysis and data from cell growth curve also indicated that expression of exogenous gene can not prolong the longevity of leukocyte,but rather inhibit the growth of leukocyte and induce its apoptosis.We conclude that expression of exogenous gene may block the coalition of telomerase RNA and its catalytic subunit(hTRT) and block the coalition of telomerase RNA template and telomere DNA,thus affecting telomerase activity and repressing cell proliferation.