Volltext-Downloads (blau) und Frontdoor-Views (grau)

Pre-stress of actin cortices is important for the viscoelastic response of living cells

  • Shape, dynamics, and viscoelastic properties of eukaryotic cells are primarily governed by a thin,reversibly cross-linked actomyosin cortex located directly beneath the plasma membrane. We obtaintime-dependent rheological responses of fibroblasts and MDCK II cells from deformation-relaxationcurves using an atomic force microscope to access the dependence of cortex fluidity on pre-stress. We introduce a viscoelastic model that treats the cell as a composite shell and assumes thatrelaxation of the cortex follows a power law giving access to cortical pre-stress, area compressibilitymodulus, and the power law (fluidity) exponent. Cortex fluidity is modulated by interferingwith myosin activity. We find that the power law exponent of the cell cortex decreases withincreasing intrinsic pre-stress and area compressibility modulus, in accordance with previousfinding for isolated actin networks subject to external stress. Extrapolation to zero tension returnsthe theoretically predicted power law exponent for transiently cross-linked polymer networks. In contrast to the widely used Hertzian mechanics, our model provides viscoelastic parametersindependent of indenter geometry and compression velocity.

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar


Document Type:Preprint
Author:Andrea Cordes, Hannes WittORCiD, Aina Gallemí-PérezORCiD, Bastian BrücknerORCiD, Florian Grimm, Marian Vache, Tabea OswaldORCiD, Jonathan BodenschatzORCiD, Daniel A. FlormannORCiD, Franziska LautenschlägerORCiD, Marco TarantolaORCiD, Andreas JanshoffORCiD
Parent Title (English):bioRxiv
Date of first Publication:2020/03/25
Release Date:2022/05/10
Funding Information:DFG (SFB937(A8): AJ and MT; SFB 1027(A9): FL) and the VW foundation (‘Living Foams’: AJ and MT)
DDC classes:500 Naturwissenschaften und Mathematik / 570 Biowissenschaften, Biologie
Open Access:Open Access
Signature:INM 2020/153_preprint
Licence (German):License LogoCreative Commons - CC BY-NC-ND - Namensnennung - Nicht kommerziell - Keine Bearbeitungen 4.0 International