Membrane biogenesis: from mechanism to disease

The biogenesis of membranes involves the continous f low of proteins and lipids which are selectively targeted to or retrieved from specific compartments within eukaryotic cells. While some diseases are caused by the impairment of particular protein transport pathways or mislocalization of a certain protein others may be related to altered signal transduction cascades resulting from defective endocytosis of plasma membrane receptors or other membrane trafficking defects. The implications of this hypothesis for our understanding of the proper functioning of a eukaryotic cell and for the treatment of human diseases are being discussed. I. Overview Unlike bacteria, eukaryotic cells are elaborately subdivided into membrane-bounded, structurally and functionally distinct compartments. Each of these organelles contains a specific set of proteins, lipids and other molecules which enables them to fulfill characteristic functions within the cell. On average, the membrane-bounded compartments ogether occupy nearly half th