Telomerase Internal template RNA (a) DNA 5'-TTTTGGGGTTTTG-OH3" CCAAAACCCCAAAA Polymerization and hybridization (b) 5′— TTTTGGGGTT'TTGGGGTTTTG-OH(3) CCAAAACCCCAAA Translocation and rehybridization TTTGGGGTTTTGGGGTTTTG-OH(3) CAAAACCCCAAAA Further polymerization