Mathematical models for cytoskeletal transport and cellular viscoelasticity

SEBASTIÁN BOUZAT

Sierra de la Ventana

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Biofísica; 2014

Sociedad Argentina de Biofísica y Universidad Nacional del Sur

P { margin-bottom: 0.21cm; direction: ltr; color: rgb(0, 0, 0); line-height: 115%; widows: 2; orphans: 2; }P.western { font-family: "Calibri","Arial",sans-serif; font-size: 11pt; }P.cjk { font-family: "Arial Unicode MS",sans-serif; font-size: 11pt; }P.ctl { font-size: 11pt; }A:link { color: rgb(0, 0, 255); }A.ctl:link { } Molecular motors use the energy from ATP hydrolysis to move cargoes of radius 100-1000 nm along the cytoeskeletal filaments. For instance, the motor proteins kinesin and dynein drive cargo transport along microtubules, while myosin motors move on actin filaments. Due to the fact that the cytoplasm is a complex environment which is crowded by polymers and macromolecules, the motors have to overcome viscous and elastic responses from the medium. In this contribution we present a general model for active cargo transport inside cells [1,2]. It combines a Langevin description of the cargo motion with a Monte Carlo dynamics ruling the motor stepping, binding and unbinding processes. We also show the way in which the elastic responses of the medium can be taken into account [3]. This is done by considering a Generalized Langevin equation for the cargo motion or, equivalently, by introducing virtual environmental particles which interact harmonically with the cargo [3,4]. We discuss some of the modeling results in connexion with recent experiments in the literature.