GTPγS-Stimulated Lysosomal Lysis Dependent on the Assembly of Adaptor Protein on Lysosome

Abstract

Cytosol treated with guanosine 5′-O-(3-thiotriphosphate) (GTPγS) destroys the dextran-loaded lysosomes (J. Biochem., 123, 637 (1998)). The transfer of the ADP-ribosylation factor (ARF) from the cytosol to the lysosomal membrane is necessary for this lysis to occur. The role of ARF in the biogenesis of the Golgi complex is to generate high-affinity membrane-binding sites for the heterotetrameric adaptor protein complex in Golgi membranes. We have found that ARF also recruits the adaptor protein to lysosomes. The recruitment of protein coats for vesicles is necessary for the GTPγS-stimulated lysis of lysosomes. The GTPγS-induced lysis proceeded via a process similar to that for the assembly of coated proteins to coated vesicles, which serve to transport proteins between intracellular organelles.