Stretching weakly bending filaments with spontaneous curvature in two dimensions.
Some important biomolecules (for instance, bacterial FtsZ and eukaryotic DNA) are known to posses spontaneous (intrinsic) curvature. Using a simple extension of the wormlike chain model, we study the response of a weakly bending filament in two dimensions to a pulling force applied at its ends (a configuration common in classical in-vitro experiments and relevant to several in-vivo cell cases). The spontaneous curvature of such a chain or filament can in general be arc-length dependent and we study a case of sinusoidal variation, from which an arbitrary case can be reconstructed via Fourier transformation. We obtain analytic results for the force-extension relationship and the width of transverse fluctuations. We show that spontaneous-curvature undulations can affect the force-extension behavior even in relatively flexible filaments with a persistence length smaller than the contour length.
Benetatos
Panayotis
P
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
Terentjev
Eugene M
EM
D001704:Biopolymers / Q000737:chemistry*; D003198:Computer Simulation; D055119:Elastic Modulus; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D013314:Stress, Mechanical
D001704:Biopolymers