ONE-STEP AFFINITY PURIFICATION PROTOCOL FOR HUMAN TELOMERASE

Human telomerase is a ribonucleoprotein (RNP) enzyme, comprising prote in components and an RNA template that catalyses telomere elongation t hrough the addition of TTAGGG repeats. Telomerase function has been im plicated in aging and cancer cell immortalization. We report a rapid a nd efficient one-step purification protocol to obtain highly active te lomerase from human cells. The purification is based on affinity chrom atography of nuclear extracts with antisense oligonucleotides compleme ntary to the template region of the human telomerase RNA component. Bo und telomerase is eluted with a displacement oligonucleotide under mil d conditions. The:resulting affinity-purified telomerase is active in PCR-amplified telomerase assays. The purified telomerase complex has a molecular mass of similar to 550 kDa compared to the similar to 1000 kDa determined for the telomerase RNP in unfractionated nuclear extrac ts. The purification protocol provides a rapid and efficient tool for functional and structural studies of human telomerase.