Teniposide, a topoisomerase II inhibitor, prevents chromosome condensation and separation but not decondensation in fertilized surf clam (Spisula solidissima) oocytes

摘要: DNA topoisomerase II has been implicated in regulating chromosome interactions. We investigated the effects of specific inhibitor, teniposide on nuclear events during oocyte maturation, fertilization, and early embryonic development fertilized Spisula solidissima oocytes using fluorescence. Teniposide treatment before fertilization not only inhibited separation meiosis, but also blocked condensation mitosis; however, sperm decondensation was unaffected. Chromosome selectively treated with either meiotic metaphase I or indicating that activity may be required maturation. meiosis disrupted mitotic condensation. anaphase unaffected embryos when chromosomes were already condensed first second next mitosis blocked. When interphase two- four-cell exposed to subsequent proceeded normally condensed, separated, decondensed; contrast, These observations suggest oocytes, is for mitosis, involved nucleus, maternal chromosomes, somatic chromatin.