TERC基因编码的功能和结构描述

端粒酶是一种核糖核蛋白聚合酶，通过增加端粒重复序列ttaggg来维持端粒末端。这种酶由具有逆转录酶活性的蛋白质组分和由该基因编码的rna组分构成端粒重复序列的模板。端粒酶的表达在细胞衰老中起作用，因为它通常在出生后的体细胞中被抑制，导致端粒的进行性缩短。端粒酶在体细胞中的表达下调可能与肿瘤的发生有关。小鼠的研究表明，端粒酶也参与染色体修复，因为端粒重复序列的从头合成可能发生在双链断裂处。该基因突变可引起常染色体显性遗传性角化不良，并可能与再生障碍性贫血有关。

Telomerase is a ribonucleoprotein polymerase that maintains telomere ends by addition of the telomere repeat TTAGGG. The enzyme consists of a protein component with reverse transcriptase activity, and an RNA component, encoded by this gene, that serves as a template for the telomere repeat. Telomerase expression plays a role in cellular senescence, as it is normally repressed in postnatal somatic cells resulting in progressive shortening of telomeres. Deregulation of telomerase expression in somatic cells may be involved in oncogenesis. Studies in mouse suggest that telomerase also participates in chromosomal repair, since de novo synthesis of telomere repeats may occur at double-stranded breaks. Mutations in this gene cause autosomal dominant dyskeratosis congenita, and may also be associated with some cases of aplastic anemia.