Entropic attraction of adhesion bonds toward cell boundaries

Noam Weil; Oded Farago

doi:10.1103/physreve.84.051907

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arXiv · 1110.4558

Entropic attraction of adhesion bonds toward cell boundaries

Noam Weil·Oded Farago

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Abstract

Adhesion bonds between membranes and surfaces are attracted to each other via effective interactions whose origin the entropy loss due to the reduction in the amplitude of the membrane thermal fluctuations in the vicinity of the adhesion bonds. These fluctuation-induced interactions are also expected to drive the adhesion bonds toward the rim of the cell, as well as toward the surfaces of membrane inclusions. In this paper, we analyze the attraction of adhesion bonds to the cell inner and outer boundaries. Our analysis shows that the probability distribution function of a single (diffusing) adhesion bond decay algebraically with the distance from the boundaries. Upon increasing the concentration of the adhesion bonds, the attraction to the boundaries becomes strongly self-screened.

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Noam Weil, Oded Farago. 2011-11-09. Entropic attraction of adhesion bonds toward cell boundaries. https://doi.org/10.1103/physreve.84.051907

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