DOI: 10.1209/epl/i2001-00563-6


Europhys. Lett., 56 (4) , pp. 603-609 (2001)

Detachment of molecular motors under tangential loading

A. Parmeggiani^{1, 2, 3}, F. Jülicher¹, L. Peliti⁴ and J. Prost<sup>1

1</sup>  Institut Curie, Physico-Chimie Curie, UMR 168 CNRS/IC 26 rue d'Ulm, F-75248 Paris Cedex 05, France
²  Institut für Theoretische Physik, T34, Physik Department, TU-München James-Franck-Straße, D-85747 Garching, Germany
³  Lyman Laboratory of Physics, Harvard University - Cambridge MA 02138, USA
⁴  Dipartimento di Scienze Fisiche and Unità INFM, Università "Federico II" Complesso Monte S. Angelo, I-80126 Napoli, Italy

(Received 5 March 2001; accepted in final form 22 August 2001)

Abstract
We introduce a general framework to study the processivity of molecular motors moving along a polar filament and discuss the average time spent attached to the filament as a function of a tangentially applied load. Our study of specific models suggests that the attachment time of a motor decreases with increasing ATP concentration and that double-headed motors such as kinesins lose their processivity under forcing conditions while processive single-headed motors are less sensitive to tangential forcing.

PACS
87.16.Nn - Motor proteins.
87.10.+e - General theory and mathematical aspects.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.


© EDP Sciences 2001