title: Lack of synchrony among multiple nuclei induces partial DNA fragmentation in V79 cells polyploidized by demecolcine.
abstract: The nuclear morphology of polyploidized cells was examined in V79 Chinese hamster cells polyploidized by demecolcine or K-252a, inhibitors of spindle fibre formation and protein kinases, respectively. A variety of nuclear morphologies, including multinuclei, were observed in V79 cells polyploidized by demecolcine but not by K-252a, which produced mononuclear cells. A lack of synchrony in the nuclear cycle was observed among nuclei in multinuclear polyploidized cells. Partial DNA fragmentation, defined as DNA fragmentation of a nucleus in a multinuclear cell, was detected using the TUNEL method in V79 cells polyploidized by demecolcine but not by K-252a. Apoptosis occurred earlier in cell populations treated with demecolcine than in these treated with K-252a once the drugs were removed from the medium, suggesting that polyploidized cells with separate nuclei tend to apoptose earlier than those with mononuclei.
authors.affiliation: Division of Basic Science, Research Institute of Medical Science, Kanazawa Medical University, Uchinada, Ishikawa, Japan. fujikawa@kanazawa-med.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Fujikawa-Yamamoto
authors.forename: C
authors.initials: C
authors.lastname: Ohdoi
authors.forename: H
authors.initials: H
authors.lastname: Yamagishi
authors.forename: Z P
authors.initials: ZP
authors.lastname: Zong
authors.forename: M
authors.initials: M
authors.lastname: Murakami
authors.forename: N
authors.initials: N
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects* / Q000648:ultrastructure; D002875:Chromosomes; D006224:Cricetinae; D003412:Cricetulus; D053938:DNA Fragmentation; D003703:Demecolcine / Q000494:pharmacology*; D005434:Flow Cytometry; D011123:Polyploidy
chemical_list: D003703:Demecolcine