Henry Wellcome Laboratory of Cell Biology, Division of Molecular and Cellular Biology, Faculty of Biomedical and Life Sciences, Davidson Building, University of Glasgow, Glasgow, G12 8QQ, UK. g.gould@bio.gla.ac.uk
The careful sorting and recycling of membranes and cargo and the intracellular delivery of proteins, toxins and viruses by endocytosis are well-established roles for the endocytic apparatus, which is present in all eukaryotic cells. Recently, it has become clear that endosomes have key roles in such diverse processes as cytokinesis, polarization and migration, in which their functions might be distinct from those classically associated with endosomes. We speculate that endosomes function as multifunctional platforms on which unique sets of molecular machines are assembled to suit different cellular roles.