title: Dynamic bonds and polar ejection force distribution explain kinetochore oscillations in PtK1 cells.
abstract: Duplicated mitotic chromosomes aligned at the metaphase plate maintain dynamic attachments to spindle microtubules via their kinetochores, and multiple motor and nonmotor proteins cooperate to regulate their behavior. Depending on the system, sister chromatids may display either of two distinct behaviors, namely (1) the presence or (2) the absence of oscillations about the metaphase plate. Significantly, in PtK1 cells, in which chromosome behavior appears to be dependent on the position along the metaphase plate, both types of behavior are observed within the same spindle, but how and why these distinct behaviors are manifested is unclear. Here, we developed a new quantitative model to describe metaphase chromosome dynamics via kinetochore-microtubule interactions mediated by nonmotor viscoelastic linkages. Our model reproduces all the key features of metaphase sister kinetochore dynamics in PtK1 cells and suggests that differences in the distribution of polar ejection forces at the periphery and in the middle of PtK1 cell spindles underlie the observed dichotomy of chromosome behavior.
authors.affiliation: Department of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA.
authors.forename: Gul
authors.initials: G
authors.lastname: Civelekoglu-Scholey
authors.forename: Bin
authors.initials: B
authors.lastname: He
authors.forename: Muyao
authors.initials: M
authors.lastname: Shen
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Wan
authors.forename: Emanuele
authors.initials: E
authors.lastname: Roscioli
authors.forename: Brent
authors.initials: B
authors.lastname: Bowden
authors.forename: Daniela
authors.initials: D
authors.lastname: Cimini
mesh_terms: D000465:Algorithms; D000818:Animals; D002460:Cell Line; D002875:Chromosomes / Q000648:ultrastructure; D003598:Cytoskeletal Proteins; D004548:Elasticity; D057809:HEK293 Cells; D006801:Humans; D007700:Kinetics; D018386:Kinetochores / Q000378:metabolism* / Q000648:ultrastructure; D008870:Microtubules / Q000648:ultrastructure; D008938:Mitosis; D008962:Models, Theoretical; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D048328:Potoroidae; D008941:Spindle Apparatus / Q000502:physiology
chemical_list: D003598:Cytoskeletal Proteins; C120529:NDC80 protein, human; D009687:Nuclear Proteins