端粒和端粒酶对于细胞生存和肿瘤发生具有非常重要的意义 ,端粒酶各个组分的结构、功能及其调控已成为肿瘤学的研究热点。端粒酶的活性有赖于其结构的完整 ,但活性变化的限速步骤是由催化亚基决定的。另外值得注意的是 ,在无端粒酶活性的永生化细胞中也有端粒长度维持现象 Telomere and telomerase play an important role in cell survival and tumorigenesis. The structure, function and regulation of telomerase components have become the hot topics in oncology. Telomerase activity depends on its structural integrity, but the rate-limiting step of the activity is determined by the catalytic subunit. It is also noteworthy that there is also telomere length maintenance in immortalized cells without telomerase activity