title: NECAP2 controls clathrin coat recruitment to early endosomes for fast endocytic recycling.
abstract: Endocytic recycling returns receptors to the plasma membrane following internalization and is essential to maintain receptor levels on the cell surface, re-sensitize cells to extracellular ligands and for continued nutrient uptake. Yet, the protein machineries and mechanisms that drive endocytic recycling remain ill-defined. Here, we establish that NECAP2 regulates the endocytic recycling of EGFR and transferrin receptor. Our analysis of the recycling dynamics revealed that NECAP2 functions in the fast recycling pathway that directly returns cargo from early endosomes to the cell surface. In contrast, NECAP2 does not regulate the clathrin-mediated endocytosis of these cargos, the degradation of EGFR or the recycling of transferrin along the slow, Rab11-dependent recycling pathway. We show that protein knockdown of NECAP2 leads to enlarged early endosomes and causes the loss of the clathrin adapter AP-1 from the organelle. Through structure-function analysis, we define the protein-binding interfaces in NECAP2 that are crucial for AP-1 recruitment to early endosomes. Together, our data identify NECAP2 as a pathway-specific regulator of clathrin coat formation on early endosomes for fast endocytic recycling.
authors.affiliation: Boston University School of Medicine, Biochemistry Department, Boston, MA 02118, USA.
authors.forename: John P
authors.identifier: 0000-0002-7862-1371
authors.initials: JP
authors.lastname: Chamberland
authors.affiliation: Boston University School of Medicine, Biochemistry Department, Boston, MA 02118, USA.
authors.forename: Lauren T
authors.identifier: 0000-0002-9622-4994
authors.initials: LT
authors.lastname: Antonow
authors.affiliation: Boston University School of Medicine, Biochemistry Department, Boston, MA 02118, USA.
authors.forename: Michel
authors.identifier: 0000-0002-5976-7973
authors.initials: M
authors.lastname: Dias Santos
authors.affiliation: Boston University School of Medicine, Biochemistry Department, Boston, MA 02118, USA britter@bu.edu.
authors.forename: Brigitte
authors.identifier: 0000-0002-0094-0460
authors.initials: B
authors.lastname: Ritter
mesh_terms: D034001:Adaptor Protein Complex Subunits / Q000235:genetics*; D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000235:genetics / Q000378:metabolism*; D022163:Clathrin-Coated Vesicles / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis / Q000235:genetics; D011992:Endosomes / Q000235:genetics / Q000378:metabolism*; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D014168:Transferrin / Q000235:genetics / Q000378:metabolism
chemical_list: D034001:Adaptor Protein Complex Subunits; D033942:Adaptor Proteins, Vesicular Transport; D002966:Clathrin; D008565:Membrane Proteins; C000621667:NECAP2 protein, human; D014168:Transferrin; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: Clathrin; EGFR; Early endosomes; Endosomal sorting; Fast recycling; Rab4