General Rab protein regulator required for vesicle formation from the Golgi complex. May control vesicle docking and fusion by mediating the action of Rab GTPases to the SNARE complexes. In addition it inhibits the removal of Rab GTPases from the membrane by GDI.
Subcellular locations: Cell membrane, Cytoplasm, Golgi apparatus, Cytoplasmic vesicle, Secretory vesicle, Synaptic vesicle
According to some authors, it is an integral membrane protein, while others showed that it is cytoplasmic and membrane-associated to Golgi and synaptic vesicles.
Ubiquitous. Strongest expression found in placenta, pituitary gland, kidney, lung and stomach.