Membrane Fluidity and Receptor Function
Membrane processes can be grossly divided into those driven by metabolic energy (active processes) and those carried out through diffusion (passive processes). Most of the membranal active processes are associated with polymerization-depolymerization processes in networks of muscle-type proteins underlying the inner membrane surface. The passive processes are spontaneous and comply with the thermodynamics of diffusion where the membrane lipid fluidity is a critical determinant. In many of the passive processes, the rates are determined by the lipid fluidity, and modulation of the membrane fluidity is directly reflected in the overall product. Manipulation of membrane processes by in vitro or in vivo alteration of lipid composition and fluidity was termed passive modulation (Shinitzky, 1979).
KeywordsReceptor Function Membrane Fluidity Lateral Diffusion Rotational Diffusion Passive Process
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