Distribution of kinetochore fragments during mitosis with unreplicated genomes.
When hydroxyurea and caffeine are added to Chinese hamster ovary cells, the cells bypass the S-phase checkpoint, and enter unscheduled mitosis. These cells build a morphologically normal spindle, and distribute unreplicated kinetochore fragments to daughters. We examined these cells and found that they undergo a full repertoire of mitotic stages, with the exception of anaphase B. Spindle elongation did not occur in these cells. When taxol was added, treated cells arrested indicating that microtubule turnover was necessary for kinetochore fragment separation. When released from taxol arrest, these cells divided. Finally, we determined that mitosis with unreplicated genome cells separated kinetochore fragments relatively equally. This mitosis is minimal, but still successful in kinetochore separation, which provides insight into the mechanism of anaphase movement.
Johnson
Mary Kathrine
MK
Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
Wise
Dwayne A
DA
D000705:Anaphase / Q000187:drug effects; D000818:Animals; D016466:CHO Cells; D002503:Centromere / Q000187:drug effects / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D016678:Genome / Q000235:genetics; D006918:Hydroxyurea / Q000494:pharmacology; D018386:Kinetochores / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D018613:Microscopy, Confocal; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis / Q000187:drug effects / Q000502:physiology*; D017239:Paclitaxel / Q000494:pharmacology; D008941:Spindle Apparatus / Q000648:ultrastructure
D002868:Chromosomal Proteins, Non-Histone; C068688:centromere protein E; D017239:Paclitaxel; D006918:Hydroxyurea