Fig. 1. Overview of the cellular mechanisms involving Alix. For clarity, growth factor receptors and viral components have been omitted, trafficking from the plasma membrane to endosomes is represented by two arrows, and focal adhesions are oversimplified. Fusion of the endosomal/MVB limiting membrane with the lysosome membrane results in the degradation of lumenal MVB vesicles by lysosomal hydrolases. Note that the association of Alix with endosomes appears to be important for its role in apoptotic signaling.