Dynamics and Rheology of Actin Solutions
نویسندگان
چکیده
We describe the dynamic behavior of semidilute solutions of actin filaments (a semiflexible polymer), pointing out some of the rheological regimes present in this biologically important system. We deduce the macroscopic storage modulus and show that over a certain frequency range semiflexible polymers show a novel variation in the shear modulus; the mechanism should be distinguished from Rouse behavior in solutions of flexible polymers.
منابع مشابه
Actin, a model semi-flexible polymer
Actin is a filamentary protein which has many remarkable properties making it an ideal system for the study of the dynamics and mechanics of semi-flexible polymer solutions and gels; actin has a persistence length of over 10 microns and can polymerize to lengths of several tens of microns, this permits the use of video microscopy and other optical methods in the study polymer dynamics. Many ass...
متن کاملElasticity of F-actin Networks
This thesis presents a study of the elasticity and microstructure of three filamentous actin (F-actin) based materials. Using bulk rheology, microrheology, multiple particle tracking and imaging techniques, we study the microscopic origins of the mechanical properties of F-actin networks. We briefly introduce aspects of F-actin and rheology essential to provide a background for and motivate thi...
متن کاملSingle polymer dynamics for molecular rheology
Single polymer dynamics offers a powerful approach to study molecular-level interactions and dynamic microstructure in materials. Direct visualization of single polymer chains has uncovered new ideas regarding the rheology and nonequilibrium dynamics of macromolecules, including the importance of molecular individualism, dynamic heterogeneity, and molecular subpopulations in governing macroscop...
متن کاملMicrostructure of Sheared Entangled Solutions of Semiflexible Polymers
We study the influence of finite shear deformations on the microstructure and rheology of solutions of entangled semiflexible polymers theoretically and by numerical simulations and experiments with filamentous actin. Based on the tube model of semiflexible polymers, we predict that large finite shear deformations strongly affect the average tube width and curvature, thereby exciting considerab...
متن کاملRheology of F-actin solutions determined from thermally driven tracer motion
We report measurements of the frequency-dependent complex shear modulus of semidilute F-actin solutions based on optical observations of the thermally-excited motion of monodisperse tracer microspheres. Because the tracer spheres cause incident laser light to be strongly scattered, we determine their average motion using diffusing wave spectroscopy (DWS). From the measured mean square displacem...
متن کامل