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Alternative mechanisms of structuring biomembranes: Self-assembly vs. self-organization

Karin John·Markus Baer
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Abstract

We study two mechanisms for the formation of protein patterns near membranes of living cells by mathematical modelling. Self-assembly of protein domains by electrostatic lipid-protein interactions is contrasted with self-organization due to a nonequilibrium biochemical reaction cycle of proteins near the membrane. While both processes lead eventually to quite similar patterns, their evolution occurs on very different length and time scales. Self-assembly produces periodic protein patterns on a spatial scale below 0.1 micron in a few seconds followed by extremely slow coarsening, whereas self-organization results in a pattern wavelength comparable to the typical cell size of 100 micron within a few minutes suggesting different biological functions for the two processes.

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Karin John, Markus Baer. 2006-11-17. Alternative mechanisms of structuring biomembranes: Self-assembly vs. self-organization. https://doi.org/10.1103/physrevlett.95.198101

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