title: TPA-induced multinucleation of a mesenchymal stem cell-like clone is mediated primarily by karyokinesis without cytokinesis, although cell-cell fusion also occurs.
abstract: The 5F9A cell, which is a mesenchymal stem cell-like clone established from rat bone marrow substrate adherent cells, can differentiate into adipocytes and osteoblasts in vitro under the appropriate conditions. Multinucleated cells could be also induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in 5F9A cells. This effect was mediated by protein kinase C. Possible mechanisms of multinucleation by TPA were hypothesized to be either karyokinesis without cytokinesis or cell-cell fusion. By observation using time-lapse phase-contrast microscopy, we determined that the multinucleated cells were generated mainly by karyokinesis without cytokinesis. Cell fusion was studied using time-lapse photography, and confocal laser scanning microscopy using two differentially labeled cells. These techniques demonstrated that multinucleated 5F9A cells could be produced by cell fusion, albeit at a low frequency. We conclude that multinucleated 5F9A cells are formed primarily by karyokinesis without cytokinesis, although some cells are also formed by cell-cell fusion.
authors.affiliation: Department of Histology and Cell Biology, Yokohama City University School of Medicine, Fukuura 3-9, Kanazawa-ku, Yokohama, Kanagawa-ken 236-0004, Japan. k6552@yokohama-cu.ac.jp
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yoshida
authors.forename: Shuichi
authors.initials: S
authors.lastname: Obata
authors.forename: Michio
authors.initials: M
authors.lastname: Ono
authors.forename: Michiyo
authors.initials: M
authors.lastname: Esaki
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Maejima
authors.forename: Hajime
authors.initials: H
authors.lastname: Sawada
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002459:Cell Fusion; D048750:Cell Nucleus Division / Q000187:drug effects*; D002999:Clone Cells; D048749:Cytokinesis / Q000187:drug effects*; D004247:DNA / Q000032:analysis; D016678:Genome; D015726:Giant Cells / Q000166:cytology* / Q000187:drug effects*; D047569:Laser Scanning Cytometry; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects*; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D004247:DNA; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate