title: beta-Arrestin inhibits NF-kappaB activity by means of its interaction with the NF-kappaB inhibitor IkappaBalpha.
abstract: In addition to their roles in desensitization and signaling of seven-membrane-spanning receptors, beta-arrestins have been more recently implicated in regulating non-seven-membrane-spanning receptor pathways. By using a yeast two-hybrid screen, we identified the inhibitor of NF-kappaB, IkappaBalpha, as a binding partner of beta-arrestin 1. Both beta-arrestin 1 and 2 interact with IkappaBalpha in transfected cells as assessed by immunoprecipitation experiments. Additionally, upstream kinases known to regulate the function of IkappaBalpha, such as IkappaB kinase alpha and beta and NF-kappaB-inducing kinase, were also shown to interact with beta-arrestin. Overexpression of either beta-arrestin 1 or beta-arrestin 2 led to marked inhibition of NF-kappaB activity, as measured by reporter gene activity. Inhibition of NF-kappaB activity was independent of the type of stimulus used for NF-kappaB activation. Conversely, suppression of beta-arrestin 1, but not beta-arrestin 2, expression by using RNA interference led to a 3-fold increase in tumor necrosis factor-stimulated NF-kappaB activity as measured by NF-kappaB mobility-shift analysis. These data uncover a role of beta-arrestins in the regulation of NF-kappaB-mediated gene regulation.
authors.affiliation: Department of Medicine and Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: D Scott
authors.initials: DS
authors.lastname: Witherow
authors.forename: Tiffany Runyan
authors.initials: TR
authors.lastname: Garrison
authors.forename: William E
authors.initials: WE
authors.lastname: Miller
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lefkowitz
mesh_terms: D019390:Arrestins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D006367:HeLa Cells; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D014162:Transfection; D020798:Two-Hybrid System Techniques; D000071559:beta-Arrestin 1; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins
chemical_list: C000605253:ARRB1 protein, human; C000605254:ARRB2 protein, human; D019390:Arrestins; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D000071559:beta-Arrestin 1; D000071560:beta-Arrestin 2; D000071557:beta-Arrestins; D000072000:NF-KappaB Inhibitor alpha