How proteins move lipids and lipids move proteins

Cells determine the bilayer characteristics of different membranes by tight ly controlling their lipid composition. Local changes in the physical prope rties of bilayers, in turn, allow membrane deformation, and facilitate vesi cle budding and fusion. Moreover, specific lipids at specific locations rec ruit cytosolic proteins involved in structural functions or signal transduc tion. We describe here how the distribution of lipids is directed by protei ns, and, conversely, how lipids influence the distribution and function of proteins.