Transient Fcho1/2⋅Eps15/R⋅AP-2 Nanoclusters Prime the AP-2 Clathrin Adaptor for Cargo Binding
Year: 2016
Type: article
Abstract: Clathrin-coated vesicles form by rapid assembly of discrete coat constituents into a cargo-sorting lattice. How the sequential phases of coat construction are choreographed is unclear, but transient protein-protein interactions mediated by short interaction motifs are pivotal. We show that arrayed Asp-Pro-Phe (DPF) motifs within the early-arriving endocytic pioneers Eps15/R are differentially decoded by other endocytic pioneers Fcho1/2 and AP-2. The structure of an Eps15/R⋅Fcho1 μ-homology domain complex reveals a spacing-dependent DPF triad, bound in a mechanistically distinct way from the mode of single DPF binding to AP-2. Using cells lacking FCHO1/2 and with Eps15 sequestered from the plasma membrane, we establish that without these two endocytic pioneers, AP-2 assemblies are fleeting and endocytosis stalls. Thus, distinct DPF-based codes within the unstructured Eps15/R C terminus direct the assembly of temporary Fcho1/2⋅Eps15/R⋅AP-2 ternary complexes to facilitate conformational activation of AP-2 by the Fcho1/2 interdomain linker to promote AP-2 cargo engagement.
Source: Developmental Cell
Institutions: University of Pittsburgh, University of Cambridge
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $5,864
Awards: Infection and Immunity, Structural Cell Biology of transport vesicle and organelle biogenesis., Clathrin-coated Vesicles and Endocytic Function, G4273598029, Cellular Medicine at the Cambridge Institute for Medical Research., Structural Cell Biology of transport vesicle and organelle biogenesis., Investigating mechanisms of interactions between viral proteins and the cellular endocytic machinery., Cellular Medicine at the Cambridge Institute for Medical Research., G9000324356
OpenAlex ID: W2399726023