Receptor aggregation by intermembrane interactions: a Monte Carlo study.

G Matthew Fricke; James L Thomas

doi:10.1016/j.bpc.2005.09.019

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Receptor aggregation by intermembrane interactions: a Monte Carlo study.

G Matthew Fricke·James L Thomas

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Abstract

The lateral organization of receptors on cell surfaces is critically important to their function; many receptors transmit transmembrane signals when redistributed into clusters, while the response of others is potentiated by their aggregation. Cell-cell contact can play a crucial role in receptor aggregation, even when the bonds between receptors on one cell and ligands on the other are monovalent. Monte Carlo simulations on a two-membrane model were carried out to determine whether weak enthalpic interactions among receptors in one membrane, and among ligands in another, can work synergistically to give large-scale clustering when the two membranes are brought into contact. The simulations give support to such a clustering mechanism. In addition, because clustering is a cooperative process akin to a phase separation, individual receptors and ligands may undergo repeated binding and unbinding while in a clustered "phase," and a single ligand could interact with multiple different receptor partners. The results suggest a resolution of the dichotomy between serial triggering and aggregation models of T cell activation.

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Cell Membrane Chemical Phenomena Chemistry, Physical Ligands Models, Chemical Monte Carlo Method Protein Conformation Receptor Aggregation Receptors, Cell Surface Signal Transduction Thermodynamics Journal Article Research Support, Non-U.S. Gov't

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G Matthew Fricke, James L Thomas. 2005-10-13. Receptor aggregation by intermembrane interactions: a Monte Carlo study.. https://doi.org/10.1016/j.bpc.2005.09.019

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