7om8
From Proteopedia
Beta2 appendage domain of AP2 bound to terminal domains beneath the hub of the 28 triskelia mini clathrin coat complex, class 15
Structural highlights
FunctionI3LGD4_PIG Clathrin is the major protein of the polyhedral coat of coated pits and vesicles.[PIRNR:PIRNR002290] Publication Abstract from PubMedClathrin-coated pits are formed by the recognition of membrane and cargo by the AP2 complex and the subsequent recruitment of clathrin triskelia. A role for AP2 in coated-pit assembly beyond initial clathrin recruitment has not been explored. Clathrin binds the beta2 subunit of AP2, and several binding sites have been identified, but our structural knowledge of these interactions is incomplete and their functional importance during endocytosis is unclear. Here, we analysed the cryo-EM structure of clathrin cages assembled in the presence of beta2 hinge-appendage (beta2HA). We find that the beta2-appendage binds in at least two positions in the cage, demonstrating that multi-modal binding is a fundamental property of clathrin-AP2 interactions. In one position, beta2-appendage cross-links two adjacent terminal domains from different triskelia. Functional analysis of beta2HA-clathrin interactions reveals that endocytosis requires two clathrin interaction sites: a clathrin-box motif on the hinge and the "sandwich site" on the appendage. We propose that beta2-appendage binding to more than one triskelion is a key feature of the system and likely explains why assembly is driven by AP2. Multi-modal adaptor-clathrin contacts drive coated vesicle assembly.,Smith SM, Larocque G, Wood KM, Morris KL, Roseman AM, Sessions RB, Royle SJ, Smith CJ EMBO J. 2021 Oct 1;40(19):e108795. doi: 10.15252/embj.2021108795. Epub 2021 Sep , 6. PMID:34487371[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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