What is the telomerase activity?
Telomerase is the enzyme responsible for maintenance of the length of telomeres by addition of guanine-rich repetitive sequences. Telomerase activity is exhibited in gametes and stem and tumor cells. Critically short telomeres cause senescence, following crisis, and cell death.
What is the absence of telomerase activity?
Abstract. In the absence of telomerase, telomeres progressively shorten with every round of DNA replication, leading to replicative senescence.
How do you upregulate telomerase?
Similar to astragalus, extracts of cycloastragenol can increase telomerase activity. Previous studies have shown that injecting the telomerase gene into the immune cells (T cells) in our body can help keep the telomeres from getting shorter and enabling them to maintain their anti-viral functioning longer.
Why is telomerase not active in somatic cells?
Telomerase activity is absent in most normal human somatic cells because of the lack of expression of TERT; TERC is usually present. On the other hand most mouse cells have telomerase activity (Blasco, 2005). The absence of telomerase activity in most human somatic cells results in telomere shortening during aging.
What is meant by telomerase?
Listen to pronunciation. (teh-LOH-meh-rays) An enzyme in cells that helps keep them alive by adding DNA to telomeres (the ends of chromosomes). Each time a cell divides, the telomeres lose a small amount of DNA and become shorter.
What is the role of telomerase in aging?
Telomeres play a central role in cell fate and aging by adjusting the cellular response to stress and growth stimulation on the basis of previous cell divisions and DNA damage. The average telomere length is set and maintained in cells of the germline which typically express high levels of telomerase.
What cells have telomerase activity?
Telomerase is found in fetal tissues, adult germ cells, and also tumor cells. Telomerase activity is regulated during development and has a very low, almost undetectable activity in somatic (body) cells. Because these somatic cells do not regularly use telomerase, they age. The result of aging cells is an aging body.
How can telomerase be inhibited?
Anticancer approaches directed at telomerase inhibition are varied, and methods ranging from RNA interference (RNAi) of the TERT catalytic subunit to inhibition of the proteins associated with telomerase at the telomeres have proven to have efficacy against cancer.
What if telomerase is active in somatic cells?
Because these somatic cells do not regularly use telomerase, they age. The result of aging cells is an aging body. If telomerase is activated in a cell, the cell will continue to grow and divide. This “immortal cell” theory is important in two areas of research: aging and cancer.