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3a58
From Proteopedia
Crystal structure of Sec3p - Rho1p complex from Saccharomyces cerevisiae
Structural highlights
Function[SEC3_YEAST] Component of the exocyst complex involved in the docking of exocytic vesicles with fusion sites on the plasma membrane. [RHO1_YEAST] Acts as a central regulator in the cell wall integrity signaling pathway, which is regulated by the cell cycle and in response to various types of cell wall stress. Integrates signals from different cell surface sensors, and activates a set of effectors, regulating processes including beta-glucan synthesis at the site of wall remodeling, gene expression related to cell wall biogenesis, organization of the actin cytoskeleton, and protein- and secretory vesicle-targeting to the growth site. Activates the protein kinase C (PKC1) MAP kinase cascade, the beta-1,3-glucan synthase (FKS1), the formin BNI1, the exocyst component SEC3 and the transcription factor SKN7.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe exocyst complex is a hetero-octameric protein complex that functions during cell polarization by tethering the secretory vesicle to the target membrane. The yeast exocyst subunit Sec3 binds to phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P(2)) and the small GTPases Rho1 and Cdc42 via its N-terminal domain (Sec3-N), and these interactions target Sec3 to the plasma membrane. Here we report the crystal structure of the Sec3-N in complex with Rho1 at 2.6-A resolution. Sec3-N adopts a pleckstrin homology (PH) fold, despite having no detectable sequence homology with other PH domains of known structure. Clusters of conserved basic residues constitute a positively charged cleft, which was identified as a binding site for PtdIns(4,5)P(2). Residues Phe77, Ile115 and Leu131 of Sec3 bind to an extended hydrophobic surface formed around switch regions I and II of Rho1. To our knowledge, these are the first structural insights into how an exocyst subunit might interact with both protein and phospholipid factors on the target membrane. Structural basis for the Rho- and phosphoinositide-dependent localization of the exocyst subunit Sec3.,Yamashita M, Kurokawa K, Sato Y, Yamagata A, Mimura H, Yoshikawa A, Sato K, Nakano A, Fukai S Nat Struct Mol Biol. 2010 Feb;17(2):180-6. Epub 2010 Jan 10. PMID:20062059[16] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Atcc 18824 | Large Structures | Fukai, S | Mimura, H | Sato, Y | Yamagata, A | Yamashita, M | Yoshikawa, A | Cell membrane | Endosome | Exocytosis | Gtp-binding | Gtpase | Lipoprotein | Membrane | Membrane traffic | Methylation | Nucleotide-binding | Peroxisome | Ph domain | Phosphoprotein | Prenylation | Protein complex | Protein transport | Protein transport-exocytosis complex | Transport
