Sec8 is a component of the exocyst complex, composed of Sec3, Sec5, Sec5, Sec6, Sec8, Sec10, Sec15, Exo70 and Exo84, which mediates the tethering of post-Golgi secretory vesicles to the plasma membrane. The exocyst promotes the assembly of SNARE complex for membrane fusion and it is also involved in many cellular processes such as cell polarisation, primary ciliogenesis, cytokinesis, pathogen invasion, tumourigenesis and metastasis [1,2]. Subunits of the exocyst have a rod structure which is a shared feature for the Complex Associated with Tethering Containing Helical Rods (CATCHRs) proteins such as those of the Conserved Oligomeric Golgi complex (COG) and Golgi-Associated Retrograde Protein complex (GARP), consisting of a N-terminal long coiled-coil followed by a region of antiparallel short helical bundle units [1,2]. This entry represents a domain found at the C-terminal of Sec8 subunit, consisting of alpha-helical bundles.

1: Cryo-EM structure of the exocyst complex. Mei K, Li Y, Wang S, Shao G, Wang J, Ding Y, Luo G, Yue P, Liu JJ, Wang X, Dong MQ, Wang HW, Guo W; Nat Struct Mol Biol. 2018;25:139-146. PMID:29335562

2: Homology and Modular Evolution of CATCHR at the Origin of the Eukaryotic Endomembrane System. Santana-Molina C, Gutierrez F, Devos DP; Genome Biol Evol. 2021; [Epub ahead of print] PMID:34061181