title: Phase Segregation of Passive Advective Particles in an Active Medium.
abstract: Localized contractile configurations or asters spontaneously appear and disappear as emergent structures in the collective stochastic dynamics of active polar actomyosin filaments. Passive particles which (un)bind to the active filaments get advected into the asters, forming transient clusters. We study the phase segregation of such passive advective scalars in a medium of dynamic asters, as a function of the aster density and the ratio of the rates of aster remodeling to particle diffusion. The dynamics of coarsening shows a violation of Porod behavior; the growing domains have diffuse interfaces and low interfacial tension. The phase-segregated steady state shows strong macroscopic fluctuations characterized by multiscaling and intermittency, signifying rapid reorganization of macroscopic structures. We expect these unique nonequilibrium features to manifest in the actin-dependent molecular clustering at the cell surface.
authors.affiliation: Simons Centre for the Study of Living Machines, National Centre for Biological Sciences (TIFR), Bangalore 560065, India.
authors.forename: Amit
authors.initials: A
authors.lastname: Das
authors.affiliation: Raman Research Institute, C.V. Raman Avenue, Bangalore 560080, India.
authors.forename: Anirban
authors.initials: A
authors.lastname: Polley
authors.affiliation: Simons Centre for the Study of Living Machines, National Centre for Biological Sciences (TIFR), Bangalore 560065, India.|Raman Research Institute, C.V. Raman Avenue, Bangalore 560080, India.
authors.forename: Madan
authors.initials: M
authors.lastname: Rao
mesh_terms: D000199:Actins / Q000737:chemistry / Q000502:physiology; D000205:Actomyosin / Q000737:chemistry / Q000502:physiology; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology*; D004058:Diffusion; D057446:Hydrodynamics; D007700:Kinetics; D008954:Models, Biological; D009010:Monte Carlo Method; D013269:Stochastic Processes
chemical_list: D000199:Actins; D000205:Actomyosin