Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
Cell Mol Biol Lett. 2013 Dec;18(4):538-54. doi: 10.2478/s11658-013-0105-0. Epub 2013 Sep 18.
The classical activity of telomerase is to synthesize telomeric repeats and thus maintain telomere length, which in turn ensures chromosome stability and cellular proliferation. However, there is growing evidence that implicates telomerase in many other functions that are independent of TERC being used as its template. Telomerase has an RNA-dependent RNA polymerase (RdRP) activity in the mitochondria. Other than viral RdRPs, it is the only RNA-dependent RNA polymerase that has been identified in mammals. It also plays a role in the Wnt signaling pathway by acting as a transcriptional modulator. Telomerase acts as a reverse transcriptase independent of its core subunit, TERC. Studies indicate that telomerase is also involved in apoptosis and DNA repair.
端粒酶的经典活性是合成端粒重复序列，从而维持端粒长度，这反过来又确保了染色体的稳定性和细胞的增殖。然而，越来越多的证据表明，端粒酶在许多其他功能中发挥作用，这些功能与 TERC 作为其模板无关。端粒酶在线粒体中具有 RNA 依赖性 RNA 聚合酶（RdRP）活性。除了病毒 RdRPs 之外，它是哺乳动物中唯一鉴定出的 RNA 依赖性 RNA 聚合酶。它还通过作为转录调节剂在 Wnt 信号通路中发挥作用。端粒酶作为一种逆转录酶，其核心亚基 TERC 并不参与其中。研究表明，端粒酶还参与细胞凋亡和 DNA 修复。
