title: Monoclonal antibody and siRNAs for topoisomerase I suppress telomerase activity.
abstract: Telomerase, a ribonucleoprotein enzyme, is a cellular RNA-dependent DNA polymerase that serves to maintain the tandem arrays of telomeric repeats at the eukaryotic chromosomal ends. We previously reported that topoisomerase I dissociates HIV-1 reverse transcriptase from genomic RNAs, and binding of topoisomerase I to RNA template regulates cDNA synthesis. We also found that a monoclonal antibody (MAb) against topoisomerase I, designated as MAb 1, suppresses the reverse transcription efficiency using a detergent-disrupted HIV-1 virion. In this study, we describe how MAb 1 suppresses telomerase activity in cellular lysates. In addition, siRNAs of topoisomerase I has attenuated telomerase activity in culture cells. These results suggest that topoisomerase I is involved in telomerase activity, as well as HIV-1 reverse transcription.
authors.affiliation: Department of Pathology, National Institute of Infectious Diseases , Toyama, Tokyo, Japan. htakahas@nih.go.jp
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Takahashi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kitagawa
authors.forename: Masae
authors.initials: M
authors.lastname: Maeda-Satoh
authors.forename: Hideki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Sawa
authors.forename: Tetsutaro
authors.initials: T
authors.lastname: Sata
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D004264:DNA Topoisomerases, Type I / Q000235:genetics / Q000276:immunology*; D004789:Enzyme Activation / Q000235:genetics / Q000276:immunology; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D034741:RNA, Small Interfering / Q000235:genetics*; D019098:Telomerase / Q000235:genetics / Q000276:immunology; D059004:Topoisomerase I Inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D034741:RNA, Small Interfering; D059004:Topoisomerase I Inhibitors; D019098:Telomerase; D004264:DNA Topoisomerases, Type I