Is the protein/lipid hydrophobic matching principle relevant to membrane organization and functions?

Abstract

Biological membranes are complex and well-organized multimolecular assemblies composed of a wide variety of protein and lipid molecular species. If such a diversity in protein and lipid polar headgroup structures may easily be related to a large panel of functions, the wide dispersion in acyl chain length and structure which the lipids display is more difficult to understand. It is not required for maintaining bilayer assembly and fluidity. Direct information on the lateral distribution of these various molecular species, on their potential specificity for interaction between themselves and with proteins and on the functional implications of these interactions is also still lacking. Because hydrophobic interactions play a major role in stabilizing membrane structures, we suggest considering the problem from the point of view of the matching of the hydrophobic surface of proteins by the acyl chains of the lipids. After a brief introduction to the hydrophobic matching principle, we will present experimental results which demonstrate the predictive power of the current theories and then, we will introduce the new and important concept of protein/lipid sorting in membranes. Finally, we will show how the hydrophobic matching condition may play a key role in the membrane organization and function.