title: RNAi knockdown of caspase-activated DNase inhibits rotenone-induced DNA fragmentation in HeLa cells.
abstract: Rotenone, an inhibitor of mitochondrial complex I, induces apoptosis in a variety of cells. However, little is known about endogenous endonucleases involved in rotenone-induced DNA fragmentation, a biochemical hallmark of apoptosis. We used a chemically modified siRNA which is thought to be more effective than a non-modified siRNA to study whether caspase-activated DNase (CAD) contributes to this phenomenon. Western blot analysis showed that CAD protein decreased to 8% of control levels in human cervical carcinoma HeLa cells after a 48h transfection of siRNA. Consistent with the reduction of the protein level, the siRNA was found to inhibit rotenone-induced DNA fragmentation. These results suggest that CAD is the endogenous endonuclease that mediates internucleosomal DNA degradation in rotenone-induced apoptosis.
authors.affiliation: Department of Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
authors.forename: Tadamiki
authors.initials: T
authors.lastname: Tsuruta
authors.forename: Kentaro
authors.initials: K
authors.lastname: Oh-Hashi
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ueno
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kitade
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Kiuchi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hirata
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000235:genetics*; D020169:Caspases / Q000378:metabolism*; D004247:DNA / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects*; D003851:Deoxyribonucleases / Q000235:genetics* / Q000378:metabolism*; D015536:Down-Regulation / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics*; D012402:Rotenone / Q000494:pharmacology; D014162:Transfection / Q000379:methods; D014475:Uncoupling Agents / Q000494:pharmacology
chemical_list: D009707:Nucleosomes; D034741:RNA, Small Interfering; D014475:Uncoupling Agents; D012402:Rotenone; D004247:DNA; D003851:Deoxyribonucleases; C109663:caspase-activated deoxyribonuclease; D020169:Caspases