Statistical mechanics of an elastically pinned membrane: Equilibrium dynamics and power spectrum
arXiv:1806.10490 · doi:10.1016/j.bpj.2019.06.036
Abstract
In biological settings membranes typically interact locally with other membranes or the extracellular matrix in the exterior, as well as with internal cellular structures such as the cytoskeleton. Characterization of the dynamic properties of such interactions presents a difficult task. Significant progress has been achieved through simulations and experiments, yet analytical progress in modelling pinned membranes has been impeded by the complexity of governing equations. Here we circumvent these difficulties by calculating analytically the time-dependent Green's function of the operator governing the dynamics of an elastically pinned membrane in a hydrodynamic surrounding and subject to external forces. This enables us to calculate the equilibrium power spectral density for an overdamped membrane pinned by an elastic, permanently-attached spring subject to thermal excitations. By considering the effects of the finite experimental resolution on the measured spectra, we show that the elasticity of the pinning can be extracted from the experimentally measured spectrum. Membrane fluctuations can thus be used as a tool to probe mechanical properties of the underlying structures. Such a tool may be particularly relevant in the context of cell mechanics, where the elasticity of the membrane's attachment to the cytoskeleton could be measured.
References in corpus (13)
- Nonequilibrium Fluctuations, Travelling Waves, and Instabilities in Active Membranes
- Active Membrane Fluctuations Studied by Micropipet Aspiration
- Dynamics of membranes driven by actin polymerization
- Effective Temperature of Red Blood Cell Membrane Fluctuations
- How cells tiptoe on adhesive surfaces before sticking
- Stochastic Eulerian Lagrangian Methods for Fluid-Structure Interactions with Thermal Fluctuations
- Model for probing membrane-cortex adhesion by micropipette aspiration and fluctuation spectroscopy
- Membrane undulations in a structured fluid: Universal dynamics at intermediate length and time scales
- Effective tension and fluctuations in active membranes
- Multiscale approaches to protein-mediated interactions between membranes - Relating microscopic and macroscopic dynamics in radially growing adhesions
- Revisiting the entropic force between fluctuating biological membranes
- Coexistence of dilute and densely packed domains of ligand-receptor bonds in membrane adhesion
- Statistical mechanics of an elastically pinned membrane: Static profile and correlations