telomeraseinTERT

Telomerase reverse transcriptase (TERT) is the catalytic subunit of telomerase, an enzyme responsible for maintaining telomere length. Telomeres are protective caps at the ends of chromosomes that shorten with each cell division. TERT, along with its RNA template component (TERC), adds repetitive DNA sequences to the ends of chromosomes, counteracting this shortening. This process is crucial for cellular immortality and preventing genomic instability.

In most somatic cells, telomerase activity is very low or absent, leading to telomere shortening and eventual cellular senescence. However, in certain cell types, such as germ cells, stem cells, and activated lymphocytes, telomerase is active, allowing these cells to divide extensively without critical telomere loss. Cancer cells often reactivate or upregulate TERT expression, contributing to their uncontrolled proliferation and immortality.

Mutations in the TERT gene or regulatory regions can lead to either increased or decreased telomerase activity, impacting various biological processes. Dysregulation of TERT has been implicated in aging and a range of diseases, including cancer, dyskeratosis congenita, and pulmonary fibrosis. Research into TERT and telomerase function is ongoing, with potential therapeutic applications aimed at targeting telomerase activity in cancer or restoring it in age-related diseases.