1xi5
Clathrin D6 coat with auxilin J-domainClathrin D6 coat with auxilin J-domain
Structural highlights
Function[CLH1_BOVIN] Clathrin is the major protein of the polyhedral coat of coated pits and vesicles. Two different adapter protein complexes link the clathrin lattice either to the plasma membrane or to the trans-Golgi network. [AUXI_BOVIN] Recruits HSPA8/HSC70 to clathrin-coated vesicles and promotes uncoating of clathrin-coated vesicles.[1] 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 PubMedClathrin-coated pits invaginate from specific membrane compartments and pinch off as coated vesicles. These vesicles then uncoat rapidly once released. The Hsc70 molecular chaperone effects the uncoating reaction, and is guided to appropriate locations on clathrin lattices by the J-domain-containing co-chaperone molecule auxilin. This raises the question of how a local event such as ATP hydrolysis by Hsc70 can catalyse a global disassembly. Here, we have used electron cryomicroscopy to determine 12-A-resolution structures of in-vitro-assembled clathrin coats in association with a carboxy-terminal fragment of auxilin that contains both the clathrin-binding region and the J domain. We have located the auxilin fragment by computing differences between these structures and those lacking auxilin (described in an accompanying paper). Auxilin binds within the clathrin lattice near contacts between an inward-projecting C-terminal helical tripod and the crossing of two 'ankle' segments; it also contacts the terminal domain of yet another clathrin 'leg'. It therefore recruits Hsc70 to the neighbourhood of a set of critical interactions. Auxilin binding produces a local change in heavy-chain contacts, creating a detectable global distortion of the clathrin coat. We propose a mechanism by which local destabilization of the lattice promotes general uncoating. Structure of an auxilin-bound clathrin coat and its implications for the mechanism of uncoating.,Fotin A, Cheng Y, Grigorieff N, Walz T, Harrison SC, Kirchhausen T Nature. 2004 Dec 2;432(7017):649-53. Epub 2004 Oct 24. PMID:15502813[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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