Rab proteins in regulated exocytosis.

Regulated exocytosis is responsible for neuronal communication, hormone secretion, food digestion, control of glucose uptake and many other basic processes. Despite the structural and functional diversity of the cells undergoing regulated exocytosis, all regulated exocytosis involves specialized vesicles that are stored in the cytoplasm and fuse with the plasma membrane in response to a trigger event. Recent evidence suggests that a subset of small GTP-binding proteins, Rab3 and its relatives, participate in the control of regulated exocytosis.