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Previously Unknown Mechanism Proposed for How Ordered Structures Arise in Cell Membranes
An explanation has been proposed for the way in which ordered structures arise in cell membranes. Scientists from the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany, have discovered how complex compounds of sugar and lipids – known as glycolipids – order themselves in cell membranes into rafts, namely small, highly organized domains. The arrangement of glycolipids on the surface of plant and animal cell membranes regulates numerous cellular processes. If errors occur in this process, diseases like paroxysmal nocturnal hemoglobinuria (PNH) and bovine spongiform encephalopathy (BSE) can arise. The results were originally published in the Angewandte Chemie International Edition on December 14, 2012. Lipids, i.e. fats and fat-like substances, arise all over the human body. They are the body’s most important energy storage system and are crucial structural components of cell membranes. Compounds formed from complex sugar components and fats are known as glycolipids. These are vital communicators found in the membranes of every human cell, and constantly exchange information about the type and state of the cell. Numerous metabolic processes depend on glycolipids and their recognition. Even the immune system identifies and combats many pathogens using certain sugar structures located on the surfaces of the pathogen cells. Glycosylphosphatidylinositols (GPIs) belong to the group of natural glycolipids. They are found on the surface of plant and animal cell membranes, where they appear either as free molecules or as membrane anchors for various proteins. The arrangement in clusters and their preference for denser and, in part, highly-organized micro-domains in the membrane are seen as essential for the effective functioning of a cell.