This group studies a fundamental aspect of cell biology such as the intracellular trafficking and topological organization of proteins resident of the Golgi complex. A major aim is to determine the protein-protein and protein-lipid interactions that influence dynamic aspects of ER-Golgi traffic and the topologic organization in the Golgi complex of Type II membrane proteins, using the glycolipid glycosyltransferases as model proteins. There is a special focus on the molecular mechanisms that influence the selective concentration of these proteins at exiting sites in the endoplasmic reticulum, as a previous step for transport to the Golgi, and to those that influence their retention in the organelle and their differential concentration in particular cisternae.