title: Disabled-2: A modular scaffold protein with multifaceted functions in signaling.
abstract: Disabled-2 (Dab2) is a multimodular scaffold protein with signaling roles in the domains of cell growth, trafficking, differentiation, and homeostasis. Emerging evidences place Dab2 as a novel modulator of cell-cell interaction; however, its mode of action has remained largely elusive. In this review, we highlight the relevance of Dab2 function in cell signaling and development and provide the most recent and comprehensive analysis of Dab2's action as a mediator of homotypical and heterotypical interactions. Accordingly, Dab-2 controls the extent of platelet aggregation through various motifs within its N-terminus. Dab2 interacts with the cytosolic tail of the integrin receptor blocking inside-out signaling, whereas extracellular Dab2 competes with fibrinogen for integrin αIIb β3 receptor binding and, thus, modulates outside-in signaling. An additional level of regulation results from Dab2's association with cell surface lipids, an event that defines the extent of cell-cell interactions. As a multifaceted regulator, Dab2 acts as a mediator of endocytosis through its association with the [FY]xNPx[YF] motifs of internalized cell surface receptors, phosphoinositides, and clathrin. Other emerging roles of Dab2 include its participation in developmental mechanisms required for tissue formation and in modulation of immune responses. This review highlights the various novel mechanisms by which Dab2 mediates an array of signaling events with vast physiological consequences.
authors.affiliation: Integrated Cellular Responses Laboratory, Department of Biological Sciences, Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA.
authors.forename: Carla V
authors.initials: CV
authors.lastname: Finkielstein
authors.affiliation: Protein Signaling Domains Laboratory, Department of Biological Sciences, Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA.
authors.forename: Daniel G S
authors.initials: DG
authors.lastname: Capelluto
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism* / Q000502:physiology; D033942:Adaptor Proteins, Vesicular Transport; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D021381:Protein Transport; D015398:Signal Transduction; D025521:Tumor Suppressor Proteins / Q000378:metabolism* / Q000502:physiology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D051017:Apoptosis Regulatory Proteins; C102885:DAB2 protein, human; C478773:Dab2 protein, mouse; D025521:Tumor Suppressor Proteins
keywords: Disabled-2; adaptor protein; endocytosis; phosphatidylinositol 4,5-bisphosphate; platelets; sulfatides; tumor suppressor