This entry represents the C-terminal domain of Sec3 (also known as ExoC1), a component of the exocyst complex (composed of Exoc1, Exoc2, Exoc3, Exoc4, Exoc5, Exoc6, Exoc7 and Exoc8) which mediates the tethering of post-Golgi secretory vesicles to the plasma membrane and promotes the assembly of the SNARE complex for membrane fusion. The exocyst is also involved in other cell processes such as cell polarisation, primary ciliogenesis, cytokinesis, and tumorigenesis and metastasis []. This complex has an elongated shape consisting of packed long rods, a structure that is shared among the Complex Associated with Tethering Containing Helical Rods (CATCHRs) proteins from related complexes such as Conserved Oligomeric Golgi complex (COG) and Golgi-Associated Retrograde Protein complex (GARP) [, , ]. Subunits of these complexes, apart of helical bundles, they usually have a coiled-coil (CC) region at the N-terminal. Sec3 is described as a membrane-anchoring component which serves as a spatial landmark in the plasma membrane for incoming secretory vesicles. Sec3 binds to the C-terminal cytoplasmic domain of GLYT1 (glycine transporter protein 1). Sec3 is recruited to the sites of polarised membrane growth through its interaction with Rho1p, a small GTP-binding protein [].
