2020/03/16 by Maayan Levin, Levin, Maayan, Raya Sorkin +11
Biochemistry, Genetics and Molecular Biology · Chemistry · Materials Science · Physics and Astronomy · #Actin #Biological Physics (physics.bio-ph) #Biology #Biophysics #Cellular Mechanics and Interactions #Chemical physics #Chemistry #Classical mechanics #Computer science #FOS: Physical sciences #Force Microscopy Techniques and Applications #Kinetics #Material Dynamics and Properties #Materials Science (cond-mat.mtrl-sci) #Materials science #Microrheology #Monomer #Network formation #Physics #Polymer #Polymerization #Soft Condensed Matter (cond-mat.soft) #Viscoelasticity #cond-mat.mtrl-sci #cond-mat.soft #physics.bio-ph
paper · pdf · doi:10.48550/arxiv.2003.07047
published in arXiv (Cornell University) (Cornell University) · 15 pages 8 figures
arxiv created 2020/03/16 · openalex publication_date 2020/03/16 · arxiv updated 2020/03/17 · openalex created_date 2022/07/26 · openalex updated_date 2026/07/28
Actin is one of the most studied cytoskeleton proteins showing a very rich span of structures. It can self-assemble actively into dynamical structures that govern the mechanical properties of the cell, its motility and its division. However, only very few studies characterize the kinetics of the active actin self-assembly process beyond the formation of an entangled network. Here, we follow actin polymerization kinetics and organization into entangled networks using time resolved passive microrheology. We establish a relationship between the initial concentration of monomers, the active polymerization and network formation kinetics, and the viscoelastic properties from the onset of actin polymerization upto the formation of a steady state entangled network. Surprisingly, we find that at high enough initial monomer concentrations the elastic modulus of the forming actin networks overshoots and then relaxes with a -2/5 power law, that we attribute to rearrangements of the network into a steady state structure.