title: Effect of dehydroaltenusin-C12 derivative, a selective DNA polymerase alpha inhibitor, on DNA replication in cultured cells.
abstract: Dehydroaltenusin is a selective inhibitor of mammalian DNA polymerase alpha (pol alpha) from a fungus (Alternaria tennuis). We have designed, synthesized, and characterized a derivative of dehydroaltenusin conjugated with a C12-alkyl side chain (dehydroaltenusin-C12 [C12]). C12 was the strongest pol alpha inhibitor in vitro. We introduced C12 into NIH3T3 cells with the help of a hypotonic shift, that is, a transient exposure of cultured cells in hypotonic buffer with small molecules which can not penetrate cells. The cells that took in C12 by hypotonic shift showed cell growth inhibition. At a low concentration (5 microM), DNA replication was inhibited and several large replication protein A (RPA) foci, which is different from dUTP foci. Furthermore, when C12 was incubated with aphidicolin, RPA foci were not observed in cells. Finally, these findings suggest that C12 inhibited DNA replication through pol alpha inhibition, and generated single-stranded DNA, resulted in uncoupling of the leading strand and lagging strand synthesis. These findings suggest that C12 could be more interesting as a molecule probe or anticancer agent than aphidicolin. C12 might provide novel markers for the development of antiproliferative drugs.
authors.affiliation: Department of Nutritional Science, Laboratory of Food & Nutritional Sciences, Kobe-Gakuin University, Kobe, Hyogo, Japan. kuriyama@s.kobegakuin.ac.jp
authors.forename: Isoko
authors.initials: I
authors.lastname: Kuriyama
authors.forename: Takeshi
authors.initials: T
authors.lastname: Mizuno
authors.forename: Keishi
authors.initials: K
authors.lastname: Fukudome
authors.forename: Kouji
authors.initials: K
authors.lastname: Kuramochi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Tsubaki
authors.forename: Takeo
authors.initials: T
authors.lastname: Usui
authors.forename: Naoko
authors.initials: N
authors.lastname: Imamoto
authors.forename: Kengo
authors.initials: K
authors.lastname: Sakaguchi
authors.forename: Fumio
authors.initials: F
authors.lastname: Sugawara
authors.forename: Hiromi
authors.initials: H
authors.lastname: Yoshida
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Mizushina
mesh_terms: D000818:Animals; D001578:Benzopyrans / Q000494:pharmacology*; D004256:DNA Polymerase I / Q000037:antagonists & inhibitors*; D004261:DNA Replication / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D051379:Mice; D041681:NIH 3T3 Cells
chemical_list: D001578:Benzopyrans; D004791:Enzyme Inhibitors; D004256:DNA Polymerase I; C095645:dehydroaltenusin