Bulletin of the American Physical Society
APS March Meeting 2014
Volume 59, Number 1
Monday–Friday, March 3–7, 2014; Denver, Colorado
Session L12: Invited Session: The Physics of Cell Division
8:00 AM–11:00 AM,
Wednesday, March 5, 2014
Sponsoring Unit: DBIO
Chair: M. Betterton, University of Colorado Boulder
Abstract ID: BAPS.2014.MAR.L12.3
Abstract: L12.00003 : A minimal model for kinetochore-microtubule dynamics*
9:12 AM–9:48 AM
Preview Abstract Abstract
(University of Pennsylvania)
During mitosis, chromosome pairs align at the center of a bipolar microtubule (MT) spindle and oscillate as MTs attaching them to the cell poles polymerize and depolymerize. The cell fixes misaligned pairs by a tension-sensing mechanism. Pairs later separate as shrinking MTs pull each chromosome toward its respective cell pole. We present a minimal model for these processes based on properties of MT kinetics. We apply the measured tension-dependence of single MT kinetics  to a stochastic many MT model, which we solve numerically and with master equations. We find that the force-velocity curve for the single chromosome system is bistable and hysteretic. Above some threshold load, tension fluctuations induce MTs to spontaneously switch from a pulling state into a growing, pushing state. To recover pulling from the pushing state, the load must be reduced far below the threshold. This leads to oscillations in the two-chromosome system. Our minimal model quantitatively captures several aspects of kinetochore dynamics observed experimentally. \\[4pt]  Akiyoshi et al. (2010) Nature 468, 576.
*This work was supported by NSF-DMR-1104637.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2014.MAR.L12.3
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