PHASE TOPOLOGY AND PERCOLATION IN MULTIPHASE LIPID BILAYERS - IS THE BIOLOGICAL MEMBRANE A DOMAIN MOSAIC

The recent literature provides strong evidence that phase separations do occur in biological membranes. Phase co-existence, as microscopic domains, raises important questions with regard to domain connectivity, phase percolation, long-range translational diffusion, lateral segregation of membrane components and efficiency of bimolecular reactions that occur in membranes. It also provides a basis for understanding several documented structural and dynamic aspects of this important cellular structure. It is suggested that changes between different phase 'landscapes' in a membrane may function as switching mechanisms for physiologically important events in a cell.