1P120 Conformational change of DNA induced by novel antitumor dinuclear Pt(II) complexes(05A.Nucleic acid: Structure & Property,Poster,The 51st Annual Meeting of the Biophysical Society of Japan)

Abstract

The repetitive TG-rich DNA sequence at the chromosome end, telomere, protects cells from the end-replication problem in eukaryotic cells. S. cerevisiae telomerase (Est2) is the reverse transcriptase responsible for extending telomeres in yeast. Pif1 helicase has been implicated in regulating the telomerase activity. We used single-molecule experiments to investigate how Pif1 helicases regulate telomerase activity. We found that Est2 telomerase stayed bound to telomere end after extension, but Pif1 helicases remove telomerase from the telomere. In the presence of Pif1 helicases, multiple runs of the telomerase-mediated telomere lengthening were observed. This suggests a model that Pif1 helicases remove telomerase from the telomere ends, allowing telomerase recycling.