title: Ligand-independent interaction of the type I interferon receptor complex is necessary to observe its biological activity.
abstract: Ectopic coexpression of the two chains of the Type I and Type III interferon (IFN) receptor complexes (IFN-αR1 and IFN-αR2c, or IFN-λR1 and IL-10R2) yielded sensitivity to IFN-alpha or IFN-lambda in only some cells. We found that IFN-αR1 and IFN-αR2c exhibit FRET only when expressed at equivalent and low levels. Expanded clonal cell lines expressing both IFN-αR1 and IFN-αR2c were sensitive to IFN-alpha only when IFN-αR1 and IFN-αR2c exhibited FRET in the absence of human IFN-alpha. Coexpression of RACK-1 or Jak1 enhanced the affinity of the interaction between IFN-αR1 and IFN-αR2c. Both IFN-αR1 and IFN-αR2c exhibited FRET with Jak1 and Tyk2. Together with data showing that disruption of the preassociation between the IFN-gamma receptor chains inhibited its biological activity, we propose that biologically active IFN receptors require ligand-independent juxtaposition of IFN receptor chains assisted by their associated cytosolic proteins.
authors.affiliation: Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, The University of Medicine and Dentistry of New Jersey, 675 Hoes Lane West, Piscataway, NJ 08855, USA. Electronic address: christopher.d.krause@gmail.com.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Krause
authors.forename: Gina
authors.initials: G
authors.lastname: Digioia
authors.forename: Lara S
authors.initials: LS
authors.lastname: Izotova
authors.forename: Junxia
authors.initials: J
authors.lastname: Xie
authors.forename: Youngsun
authors.initials: Y
authors.lastname: Kim
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Schwartz
authors.forename: Olga V
authors.initials: OV
authors.lastname: Mirochnitchenko
authors.forename: Sidney
authors.initials: S
authors.lastname: Pestka
mesh_terms: D002460:Cell Line; D031541:Fluorescence Resonance Energy Transfer; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D016898:Interferon-alpha / Q000378:metabolism*; D007371:Interferon-gamma / Q000378:metabolism*; D053613:Janus Kinase 1 / Q000378:metabolism; D046912:Multiprotein Complexes; D009363:Neoplasm Proteins / Q000378:metabolism; D011485:Protein Binding; D053633:Receptor, Interferon alpha-beta / Q000378:metabolism*; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface / Q000378:metabolism; D017471:Receptors, Interferon / Q000378:metabolism*; D053634:TYK2 Kinase / Q000378:metabolism; D000096743:Interferon gamma Receptor
chemical_list: D019204:GTP-Binding Proteins; D016898:Interferon-alpha; D007371:Interferon-gamma; D053613:Janus Kinase 1; D046912:Multiprotein Complexes; D009363:Neoplasm Proteins; D053633:Receptor, Interferon alpha-beta; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface; D017471:Receptors, Interferon; D053634:TYK2 Kinase; D000096743:Interferon gamma Receptor; C507964:IFNAR1 protein, human; C508033:IFNAR2 protein, human; C419368:RACK1 protein, human; C507904:JAK1 protein, human; C070139:TYK2 protein, human
keywords: CiFP; Confocal fluorescence spectroscopy; ECFP; EGFP; EYFP; FRET; IFN; IFN-α; IFN-γ; IFN-λ; Interferon receptor; OFP; RACK-1; Receptor reconstitution; StFP; enhanced citrine fluorescent protein; enhanced cyan fluorescent protein; enhanced green fluorescent protein; enhanced yellow fluorescent protein; fluorescence resonance energy transfer; interferon; interferon-alpha; interferon-gamma; interferon-lambda; orange fluorescent protein; receptor for activated protein kinase-1; strawberry fluorescent protein