title: ARAP, a Novel Adaptor Protein, Is Required for TCR Signaling and Integrin-Mediated Adhesion.
abstract: A novel adaptor protein was identified by analyzing phosphotyrosine proteomes from membrane rafts of activated T cells. This protein showed sequence similarity to a well-known T cell adaptor protein, adhesion and degranulation-promoting adaptor protein (ADAP); therefore, the novel protein was designated activation-dependent, raft-recruited ADAP-like phosphoprotein (ARAP). Suppression of ARAP impaired the major signaling pathways downstream of the TCR. ARAP associated with the Src homology 2 domain of Src homology 2-containing leukocyte protein of 76 kDa via the phosphorylation of two YDDV motifs in response to TCR stimulation. ARAP also mediated integrin activation but was not involved in actin polymerization. The results of this study indicate that a novel T cell adaptor protein, ARAP, plays a unique role in T cells as a part of both the proximal activation signaling and inside-out signaling pathways that result in integrin activation and T cell adhesion.
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea;
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Jung
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 03760, Korea; and.
authors.forename: Eun Hye
authors.initials: EH
authors.lastname: Yoo
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 03760, Korea; and.
authors.forename: Mi Jin
authors.initials: MJ
authors.lastname: Yu
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea;
authors.forename: Hyeon Myeong
authors.initials: HM
authors.lastname: Song
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea;
authors.forename: Hee Yoon
authors.initials: HY
authors.lastname: Kang
authors.affiliation: Department of Veterinary Biochemistry, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea.
authors.forename: Je-Yoel
authors.initials: JY
authors.lastname: Cho
authors.affiliation: Department of Life Science, College of Natural Sciences, Ewha Womans University, Seoul 03760, Korea; Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 03760, Korea; and jrlee@ewha.ac.kr.
authors.forename: Jong Ran
authors.initials: JR
authors.lastname: Lee
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000276:immunology* / Q000378:metabolism; D002448:Cell Adhesion / Q000276:immunology*; D002460:Cell Line; D006801:Humans; D007150:Immunohistochemistry; D016023:Integrins / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*; D021962:Membrane Microdomains / Q000276:immunology / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D016023:Integrins; D011948:Receptors, Antigen, T-Cell