title: The A20 protein interacts with the Epstein-Barr virus latent membrane protein 1 (LMP1) and alters the LMP1/TRAF1/TRADD complex.
abstract: The Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) interacts with the tumor necrosis factor receptor (TNFR)-associated factor (TRAF) molecules, which are important for LMP1-mediated signaling. Two domains of LMP1 can independently activate NF-kB, carboxyl-terminal activating region 1 (CTAR1) and CTAR2. The activation of NF-kB by CTAR1 occurs through direct interaction of LMP1 with the TRAF molecules, whereas CTAR2 interacts with the TNFR-associated death domain protein (TRADD) to activate NF-kB and the c-Jun N-terminal kinase (JNK). A20, which is induced by LMP1 through NF-kB, can block NF-kB activation from both domains of LMP1 and inhibit JNK activation from CTAR2. A20 also has been shown to associate with TRAF1 and TRAF2. In this study, an interaction between LMP1 and A20 was detected that was increased by TRAF2 overexpression. A20 did not affect the association of TRAF1 with TRAF2 but did displace TRAF1 from the LMP1 complex. The interaction of LMP1 and TRADD was decreased in the presence of A20, and the LMP1-A20 association was decreased by TRADD, suggesting that A20 and TRADD both interact with LMP1 and may compete for binding. These data indicate that A20 alters the interactions between LMP1 and the TRAF molecules and TRADD, affecting the activation of NF-kB, JNK, and perhaps other TRAF-mediated signaling events.
authors.affiliation: Department of Microbiology and Immunology and the Lineberger Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7295, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Fries
authors.forename: W E
authors.initials: WE
authors.lastname: Miller
authors.forename: N
authors.initials: N
authors.lastname: Raab-Traub
mesh_terms: D000818:Animals; D001665:Binding Sites; D002289:Carcinoma, Non-Small-Cell Lung; D003546:Cysteine Endopeptidases; D004268:DNA-Binding Proteins; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008175:Lung Neoplasms; D051379:Mice; D008956:Models, Chemical; D016328:NF-kappa B / Q000378:metabolism; D009687:Nuclear Proteins; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction; D053199:TNF Receptor-Associated Death Domain Protein; D047990:TNF Receptor-Associated Factor 1; D014407:Tumor Cells, Cultured; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D014409:Tumor Necrosis Factor-alpha / Q000737:chemistry / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B; D009687:Nuclear Proteins; D011506:Proteins; D018124:Receptors, Tumor Necrosis Factor; D053199:TNF Receptor-Associated Death Domain Protein; D047990:TNF Receptor-Associated Factor 1; C481226:Tradd protein, mouse; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins; D014409:Tumor Necrosis Factor-alpha; D016159:Tumor Suppressor Protein p53; D014763:Viral Matrix Proteins; C076529:TNFAIP3 protein, human; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D003546:Cysteine Endopeptidases; C513261:Tnfaip3 protein, mouse