title: Line tension and stability of domains in cell-adhesion zones mediated by long and short receptor-ligand complexes.
abstract: Submicron scale domains of membrane-anchored receptors play an important role in cell signaling. Central questions concern the stability of these microdomains, and the mechanisms leading to the domain formation. In immune-cell adhesion zones, microdomains of short receptor-ligand complexes form next to domains of significantly longer receptor-ligand complexes. The length mismatch between the receptor-ligand complexes leads to membrane deformations and has been suggested as a possible cause of the domain formation. The domain formation is a nucleation and growth process that depends on the line tension and free energy of the domains. Using a combination of analytical calculations and Monte Carlo simulations, we derive here general expressions for the line tension between domains of long and short receptor-ligand complexes and for the adhesion free energy of the domains. We argue that the length mismatch of receptor-ligand complexes alone is sufficient to drive the domain formation, and obtain submicron-scale minimum sizes for stable domains that are consistent with the domain sizes observed during immune-cell adhesion.
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Department of Theory and Bio-Systems, Potsdam, Germany.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Krobath
authors.forename: Bartosz
authors.initials: B
authors.lastname: Różycki
authors.forename: Reinhard
authors.initials: R
authors.lastname: Lipowsky
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Weikl
mesh_terms: D000465:Algorithms; D000818:Animals; D002448:Cell Adhesion; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D003198:Computer Simulation; D006801:Humans; D008024:Ligands; D021962:Membrane Microdomains / Q000737:chemistry / Q000378:metabolism*; D008954:Models, Biological; D009010:Monte Carlo Method; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015398:Signal Transduction; D013500:Surface Tension; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D008024:Ligands; D011948:Receptors, Antigen, T-Cell; D011956:Receptors, Cell Surface