title: Transient Fcho1/2⋅Eps15/R⋅AP-2 Nanoclusters Prime the AP-2 Clathrin Adaptor for Cargo Binding.
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.
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Perunthottathu K
authors.initials: PK
authors.lastname: Umasankar
authors.affiliation: Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK.
authors.forename: Antoni G
authors.initials: AG
authors.lastname: Wrobel
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Lymar
authors.affiliation: Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK.
authors.forename: Airlie J
authors.initials: AJ
authors.lastname: McCoy
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Sachin S
authors.initials: SS
authors.lastname: Holkar
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Anupma
authors.initials: A
authors.lastname: Jha
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Tirthadipa
authors.initials: T
authors.lastname: Pradhan-Sundd
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA.
authors.forename: Simon C
authors.initials: SC
authors.lastname: Watkins
authors.affiliation: Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Owen
authors.affiliation: Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, S312 BST, Pittsburgh, PA 15261, USA. Electronic address: traub@pitt.edu.
authors.forename: Linton M
authors.initials: LM
authors.lastname: Traub
mesh_terms: D033962:Adaptor Protein Complex 2 / Q000737:chemistry / Q000378:metabolism*; D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D002966:Clathrin / Q000378:metabolism; D022163:Clathrin-Coated Vesicles / Q000378:metabolism; D004705:Endocytosis; D050556:Fatty Acid-Binding Proteins; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008954:Models, Biological; D008958:Models, Molecular; D011485:Protein Binding; D000072417:Protein Domains; D060066:Protein Interaction Maps; D051381:Rats; D014162:Transfection
chemical_list: D033962:Adaptor Protein Complex 2; D048868:Adaptor Proteins, Signal Transducing; D002966:Clathrin; C486206:EPS15 protein, human; C524557:FCHO1 protein, human; C497031:FCHO2 protein, human; D050556:Fatty Acid-Binding Proteins; D008565:Membrane Proteins