EXOC2 (exocyst complex component 2),also known as SEC5 and SEC5L1,is a component of the exocyst complex,and is required to mediate RalB-dependent survival signals in transformed cells. The exocyst complex,composed of eight evolutionarily conserved subunits (SEC3,SEC5,SEC6,SEC8,SEC10,SEC15,EXO70,and EXO84),is involved in tethering post-Golgi secretory vesicles to specific plasma membrane domains. The gene of EXOC2 maps to chromosome 6p25.3,and encodes a 924-amino acid protein with an experimentally determined molecular mass of 95-100 kDa. EXOC2 mRNA is widely expressed with highest levels in brain and placenta.