Newby, Jay and Bressloff, P. C. (2010) Random intermittent search and the tugofwar model of motordriven transport. ? . (Submitted)

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Abstract
We formulate the tugofwar model of microtubule cargo transport by multiple molecular motors as an intermittent random search for a hidden target. A motorcomplex consisting of multiple molecular motors with opposing directional preference is modeled using a discrete Markov process. The motors randomly pull each other off of the microtubule so that the state of the motorcomplex is determined by the number of bound motors. The tugofwar model prescribes the state transition rates and corresponding cargo velocities in terms of experimentally measured physical parameters. We add space to the resulting ChapmanKolmogorov (CK) equation so that we can consider delivery of the cargo to a hidden target somewhere on the microtubule track. Using a quasisteady state (QSS) reduction technique we calculate analytical approximations of the mean first passage time (MFPT) to find the target. We show that there exists an optimal adenosine triphosphate (ATP)concentration that minimizes the MFPT for two different cases: (i) the motor complex is composed of equal numbers of kinesin motors bound to two different microtubules (symmetric tugofwar model), and (ii) the motor complex is composed of different numbers of kinesin and dynein motors bound to a single microtubule(asymmetric tugofwar model).
Item Type:  Article 

Subjects:  D  G > General 
Research Groups:  Oxford Centre for Collaborative Applied Mathematics 
ID Code:  957 
Deposited By:  Ruby Hawkins 
Deposited On:  02 Sep 2010 09:46 
Last Modified:  29 May 2015 18:38 
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