telomeraza

Telomerase is a ribonucleoprotein complex that is responsible for the maintenance of telomeres, the protective caps at the ends of eukaryotic chromosomes. Telomeres are essential for the stability and integrity of the genome, as they prevent the loss of genetic information during cell division. Telomerase consists of two main components: the telomerase RNA (TERC) and the telomerase reverse transcriptase (TERT). TERC provides the template for telomere elongation, while TERT catalyzes the addition of DNA nucleotides to the 3' end of the telomere.

Telomerase activity is typically high in germ cells, embryonic cells, and some cancer cells, where it is crucial for the maintenance of telomere length. In most somatic cells, telomerase activity is low or absent, leading to a gradual shortening of telomeres with each cell division. This process, known as the "end replication problem," can result in cellular senescence or apoptosis if telomeres become too short.

Telomerase has been a subject of intense research due to its potential implications in aging, cancer, and regenerative medicine. In cancer, telomerase activation is often associated with immortalization and tumor progression. Conversely, telomerase inhibition has been explored as a potential therapeutic strategy for cancer treatment. In the context of aging, telomere attrition is a key factor in the aging process, and telomerase reactivation has been proposed as a potential anti-aging intervention.

The regulation of telomerase activity is complex and involves multiple mechanisms. TERT expression is controlled at the transcriptional and post-transcriptional levels, and its activity can be influenced by various factors, including DNA damage, oxidative stress, and epigenetic modifications. Understanding the regulation of telomerase is crucial for developing targeted therapies and interventions that modulate telomerase activity for therapeutic purposes.