Moskalenko, S., Henry, D.O., Rosse, C., Mirey, G., Camonis, J.H., White, M.A. (2002). The exocyst is a Ral effector complex.  Nat. Cell Biol. 4(1): 66--72.

FBrf0159810

Research paper

Delivery of cytoplasmic vesicles to discrete plasma-membrane domains is critical for establishing and maintaining cell polarity, neurite differentiation and regulated exocytosis. The exocyst is a multisubunit complex required for vectorial targeting of a subset of secretory vesicles. Mechanisms that regulate the activity of this complex in mammals are unknown. Here we show that Sec5, an integral component of the exocyst, is a direct target for activated Ral GTPases. Ral GTPases regulate targeting of basolateral proteins in epithelial cells, secretagogue-dependent exocytosis in neuroendocrine cells and assembly of exocyst complexes. These observations define Ral GTPases as critical regulators of vesicle trafficking.