MEMBRANE TRAFFICKING ALONG THE PHAGOCYTIC PATHWAY

Phagosome maturation involves extensive remodelling of the phagosomal membrane as a result of intracellular transport events. Newly formed p hagosomes exchange membrane-associated and soluble proteins with early endosomes by fusion. Budding of vesicles from the phagosome and fusio n with Golgi-derived vesicles may also contribute to the remodelling o f the phagosomal compartment. As a consequence of changes in membrane composition, phagosomes acquire the ability to fuse with late endocyti c compartments. In vitro reconstitution and other studies suggest that the trafficking events underlying phagosome maturation require severa l GTP-binding proteins, including Rab5 and G(alpha s), NSF-SNAP-SNARE complexes and coatomers.