title: Quantitative proteomics identifies a Dab2/integrin module regulating cell migration.
abstract: Clathrin-associated endocytic adapters recruit cargoes to coated pits as a first step in endocytosis. We developed an unbiased quantitative proteomics approach to identify and quantify glycoprotein cargoes for an endocytic adapter, Dab2. Surface levels of integrins beta1, alpha1, alpha2, and alpha3 but not alpha5 or alphav chains were specifically increased on Dab2-deficient HeLa cells. Dab2 colocalizes with integrin beta1 in coated pits that are dispersed over the cell surface, suggesting that it regulates bulk endocytosis of inactive integrins. Depletion of Dab2 inhibits cell migration and polarized movement of integrin beta1 and vinculin to the leading edge. By manipulating intracellular and surface integrin beta1 levels, we show that migration speed correlates with the intracellular integrin pool but not the surface level. Together, these results suggest that Dab2 internalizes integrins freely diffusing on the cell surface and that Dab2 regulates migration, perhaps by maintaining an internal pool of integrins that can be recycled to create new adhesions at the leading edge.
authors: Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
authors: Anjali
authors: A
authors: Teckchandani
authors: Natalie
authors: N
authors: Toida
authors: Jake
authors: J
authors: Goodchild
authors: Christine
authors: C
authors: Henderson
authors: Julian
authors: J
authors: Watts
authors: Bernd
authors: B
authors: Wollscheid
authors: Jonathan A
authors: JA
authors: Cooper
mesh_terms: D033962:Adaptor Protein Complex 2 / Q000378:metabolism; D048868:Adaptor Proteins, Signal Transducing / Q000172:deficiency / Q000378:metabolism*; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D002462:Cell Membrane / Q000378:metabolism; D002465:Cell Movement; D002966:Clathrin / Q000378:metabolism; D004705:Endocytosis; D006367:HeLa Cells; D006801:Humans; D039423:Integrin alpha1 / Q000378:metabolism; D019012:Integrin beta1 / Q000378:metabolism; D016023:Integrins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D009419:Nerve Tissue Proteins / Q000378:metabolism; D021381:Protein Transport; D040901:Proteomics; D025521:Tumor Suppressor Proteins
chemical_list: D033962:Adaptor Protein Complex 2; D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; D002966:Clathrin; C102885:DAB2 protein, human; D039423:Integrin alpha1; D019012:Integrin beta1; D016023:Integrins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C113026:NUMB protein, human; D025521:Tumor Suppressor Proteins