title: Inhibition of chromosome separation in fertilized starfish eggs by kalihinol F, a topoisomerase I inhibitor obtained from a marine sponge.
abstract: Kalihinol F, a naturally occurring diterpene from a marine sponge, Acanthella sp., inhibited chromosome separation in fertilized starfish (Asterina pectinifera) eggs but allows the first cleavage to occur, thereby forming unseparated metaphase chromosomes which were elongated between the two daughter cells. The chromosomes were eventually torn off in the embryonic cells. Most of the cells gradually lost the chromosomes during the cell cycle progression. The embryonic development halted at the morula stage just before the onset of blastulation. The mitotic failure occurred when kalihinol F was applied to a fertilized egg during the second meiotic process, but not after the completion of the second meiotic division. Kalihinol F inhibited topoisomerase I activity in vitro, but had no effects on activities of DNA polymerases alpha, beta, and gamma, and of topoisomerase II. These results suggest that the topoisomerase I plays an essential role in meiosis II in this species.
authors.affiliation: Instrument Center for Chemical Analysis and Department of Applied Chemistry, Hiroshima University, Higashi-Hiroshima, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Ohta
authors.forename: Shinji
authors.initials: S
authors.lastname: Ohta
authors.forename: Tomokatsu
authors.initials: T
authors.lastname: Hongo
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Hamaguchi
authors.forename: Toshiwo
authors.initials: T
authors.lastname: Andoh
authors.forename: Masaki
authors.initials: M
authors.lastname: Shioda
authors.forename: Susumu
authors.initials: S
authors.lastname: Ikegami
mesh_terms: D000818:Animals; D002875:Chromosomes / Q000648:ultrastructure*; D004224:Diterpenes / Q000302:isolation & purification / Q000494:pharmacology*; D004791:Enzyme Inhibitors; D005306:Fertilization; D009570:Nitriles / Q000302:isolation & purification / Q000494:pharmacology*; D011161:Porifera; D013215:Starfish / Q000502:physiology*; D059004:Topoisomerase I Inhibitors
chemical_list: D004224:Diterpenes; D004791:Enzyme Inhibitors; D009570:Nitriles; D059004:Topoisomerase I Inhibitors; C488364:kalihinol F