Telomerase reverse transcriptase (TERT) is an essential enzyme that plays a crucial role in maintaining the stability and functionality of telomeres, the protective caps located at the ends of chromosomes. Telomeres comprise repetitive nucleotide sequences that prevent the erosion and fusion of chromosomes during DNA replication. As cells divide, the telomeres progressively shorten, leading to cellular senescence or programmed cell death.
Telomerase reverse transcriptase is a catalytic subunit of the telomerase enzyme complex, responsible for synthesizing and adding telomeric DNA repeats to the ends of chromosomes. It possesses unique properties that allow it to reverse transcribe an RNA template into DNA, effectively extending the telomere length and counteracting its natural shortening. By replenishing telomeric DNA, TERT confers immortality to certain cells, including stem cells, germ cells, and most notably, cancer cells.
The expression of telomerase reverse transcriptase is tightly regulated in normal somatic cells, with its activity typically repressed. However, it is often reactivated during embryonic development and in various malignancies, contributing to unrestricted cell proliferation and tumor formation. In cancer research, TERT is considered an attractive target for therapeutic interventions, as its inhibition could potentially lead to the selective death of cancer cells while sparing healthy cells.
Understanding the structure, function, and regulation of telomerase reverse transcriptase remains a subject of intense scientific investigation, with potential implications for both aging-related diseases and anticancer therapies.
