Xing, YiBöcking, TillWolf, MatthiasGrigorieff, NikolausKirchhausen, TomasHarrison, Stephen2010-10-062010Xing, Yi, Till Böcking, Matthias Wolf, Nikolaus Grigorieff, Tomas Kirchhausen, and Stephen C. Harrison. 2010. Structure of clathrin coat with bound Hsc70 and auxilin: Mechanism of Hsc70-facilitated disassembly. EMBO Journal 29(3): 655-665.0261-4189http://nrs.harvard.edu/urn-3:HUL.InstRepos:4460783The chaperone Hsc70 drives the clathrin assembly–disassembly cycle forward by stimulating dissociation of a clathrin lattice. A J-domain containing co-chaperone, auxilin, associates with a freshly budded clathrin-coated vesicle, or with an in vitro assembled clathrin coat, and recruits Hsc70 to its specific heavy-chain-binding site. We have determined by electron cryomicroscopy (cryoEM), at about 11 Å resolution, the structure of a clathrin coat (in the D6-barrel form) with specifically bound Hsc70 and auxilin. The Hsc70 binds a previously analysed site near the C-terminus of the heavy chain, with a stoichiometry of about one per three-fold vertex. Its binding is accompanied by a distortion of the clathrin lattice, detected by a change in the axial ratio of the D6 barrel. We propose that when Hsc70, recruited to a position close to its target by the auxilin J-domain, splits ATP, it clamps firmly onto its heavy-chain site and locks in place a transient fluctuation. Accumulation of the local strain thus imposed at multiple vertices can then lead to disassembly.en-USclathrin-coated vesicleelectron cryomicroscopymembrane trafficJournal Article2010-10-0610.1038/emboj.2009.383