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Cell biology

Telomerase

Telomerase is a ribonucleoprotein reverse transcriptase (TERT plus the TERC RNA template) that adds TTAGGG repeats to chromosome ends, counteracting replicative shortening. It is highly active in germline, stem, and most cancer cells but largely silenced in adult somatic tissues. In longevity research, telomerase reactivation has extended healthspan in mice, but it carries oncogenic risk because most human tumors depend on telomerase for unlimited proliferation.