טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentTimchenko Boris
SubjectThe Force Exerted by an Actin Filament
DepartmentDepartment of Physics
Supervisor Professor Yariv Kafri
Full Thesis textFull thesis text - English Version


Abstract


Actin filaments are polymers made of subunits which can attach and detach, usually at and from its ends. This feature, along with other properties, enables actin filaments to perform work and to apply forces. The goal of this work is to study these forces. In this work we present a model in which these forces are studied. In this model we consider a single actin filament as a polymer growing in a one-dimensional system. We allow two types of subunits to construct the polymer, and include a process that can turn one type to the other. This feature models the chemical process of hydrolysis occurring in actin filaments. Another feature included in this model is a boundary which is described by a potential. With this, we allow the polymer to interact with the wall. The force exerted by the polymer on this wall is studied. This approach was not considered in previously studied models of the forces exerted by actin filaments. Results from numerical simulations of the presented model suggest that the force depends on the details of the wall potential, namely on its strength. This implies that the pressure of the system does not admit an equation of state. The latter may suggest a situation in which a change in the local chemical or physical conditions at the boundary of the system can lead to a change in the force exerted by the filament.