The Exo70 protein is a subunit of the exocyst complex [1-5], first identified in yeast, which is evolutionarily conserved in eukaryotes. It mediates the tethering of post-Golgi secretory vesicles to the plasma membrane and promotes the assembly of the SNARE complex for membrane fusion. It also plays a role in cell polarisation, primary ciliogenesis, cytokinesis, pathogen invasion, tumourigenesis and metastasis [2]. It is a member of the the Complex Associated with Tethering Containing Helical Rods (CATCHRs) family which also includes Conserved Oligomeric Golgi complex (COG) and Golgi-Associated Retrograde Protein complex (GARP) and DSL1 complexes, all evolutionarily related and share structural features consisting of alpha-helical bundles at the C-terminus and coiled-coil region at the N-terminus [2,3]. Exo70 interacts with the Rho3 GTPase and phospholipids [4,5]. This entry represents the N-terminal coiled-coil region which participates in the central pair-wise interactions by forming an antiparallel 'zipper' with Exo84 subunit. Exo70-Exo84 'zipper' interacts with Sec10-Sec15 counterpart to form a four-helical bundle [2].

1: Crystal Structure of the S.cerevisiae Exocyst Component Exo70p. Hamburger ZA, Hamburger AE, West AP Jr, Weis WI; J Mol Biol. 2005; [Epub ahead of print] PMID:16359701

2: 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

3: 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

4: Rho3 of Saccharomyces cerevisiae, which regulates the actin cytoskeleton and exocytosis, is a GTPase which interacts with Myo2 and Exo70. Robinson NG, Guo L, Imai J, Toh-E A, Matsui Y, Tamanoi F; Mol Cell Biol 1999;19:3580-3587. PMID:10207081

5: Exo70 interacts with phospholipids and mediates the targeting of the exocyst to the plasma membrane. He B, Xi F, Zhang X, Zhang J, Guo W; EMBO J. 2007;26:4053-4065. PMID:17717527