RESUMO
As a part of our efforts to create a pre-made multi-fluorescent cell library for various cytological assays, we made a triple-fluorescent cell line in which microtubules, chromosomes, and nuclear envelopes were visualized for simultaneous observation of spindle structure and chromosome distribution in living cells. Pilot experiments with microtubule-disturbing drugs showed the advantages of this cell line in mitosis inhibitor studies.
Assuntos
Cromatina , Microtúbulos , Mitose/efeitos dos fármacos , Membrana Nuclear , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Microscopia de Fluorescência , Microscopia de Vídeo , Paclitaxel/farmacologia , PlasmídeosRESUMO
Treatment of cells with docetaxel at low concentrations induces aberrant bipolar spindles of which two centrosomes stay at only one pole, and also induces multipolar spindles. To gain insight into the relations between centrosome impairment and structural defects of the spindle, live-cell imaging was performed on a human MDA Auro/imp/H3 cell line in which centrosomes/mitotic spindles, nuclear membrane and chromatin were simultaneously visualized by fluorescent proteins. In the presence of docetaxel at IC(50) concentration, the centrosomes did not segregate, and multiple aster-like structures ectopically arose around the disappearing nuclear membrane. Those ectopic structures formed an acentrosomal pole opposing to the two-centrosomes-containing pole. In late metaphase, one pole often fragmented into multiple spindle poles, leading multipolar division. These results suggest that spindle pole fragility may be induced by centrosome impairment, and collapse of the pole may contribute to induction of aneuploid daughter cells.
