The telomere terminal transferase of Tetrahymena is a ribonucleoprotein enzyme with two kinds of primer specificity. A telomeric sequence in the RNA of Tetrahymena telomerase required for telomere repeat synthesis. Telomeres shorten during ageing of human fibroblasts. Telomerase primer specificity and chromosome healing. Telomerase is processive.
Telomere length predicts the replicative capacity of human fibroblasts.
Telomere end replication problem and cell aging. Telomere shortening associated with chromosome instability is arrested in immortal cells which express telomerase activity. Tetrahymena telomerase RNA levels increase during macronuclear development. Tetrahymena telomerase catalyzes nucleolytic cleavage and nonprocessive elongation. Identification of a nonprocessive telomerase activity from mouse cells.