This project expands the scope of our studies in a cell biology direction. We investigate fusion/docking and sorting/budding in early endosomes (using material mainly from the neuroendocrine cell line PC12). We perform both live-cell and purified organelle assays. The assays are complemented by an investigation of protein domains on endosomes via STED and electron microscopy. Pursuing this project in the direction of investigating endosome-to-Golgi trafficking (as well as Golgi trafficking itself) is envisaged.