Golgin‐84 is a rab1 Binding Partner Involved in Golgi Structure

Members of the golgin family of coiled‐coil proteins have been implicated in the tethering of vesicles to Golgi membranes and cisternal membranes to each other. Many also bind to rab GTPases. Golgin‐84 is a membrane‐anchored golgin that we now show binds preferentially to the GTP form of the rab1 GTPase. It is also present throughout the Golgi stack by immuno‐EM. Antibodies to golgin‐84 inhibit stacking of cisternal membranes in a cell‐free assay for Golgi reassembly, whereas the cytoplasmic domain of golgin‐84 stimulates stacking and increases the length of re‐assembled stacks. Transient expression of golgin‐84 in NRK cells helps prevent the disassembly of the Golgi apparatus normally triggered by treatment with brefeldin A. Together these data suggest that golgin‐84 is involved in generating and maintaining the architecture of the Golgi apparatus.