title: Control of canonical NF-kappaB activation through the NIK-IKK complex pathway.
abstract: Articles in recent years have described two separate and distinct NF-kappaB activation pathways that result in the differential activation of p50- or p52-containing NF-kappaB complexes. Studies examining tumor-necrosis factor receptor-associated factors (TRAFs) have identified positive roles for TRAF2, TRAF5, and TRAF6, but not TRAF3, in canonical (p50-dependent) NF-kappaB activation. Conversely, it recently was reported that TRAF3 functions as an essential negative regulator of the noncanonical (p52-dependent) NF-kappaB pathway. In this article, we provide evidence that TRAF3 potently suppresses canonical NF-kappaB activation and gene expression in vitro and in vivo. We also demonstrate that deregulation of the canonical NF-kappaB pathway in TRAF3-deficient cells results from accumulation of NF-kappaB-inducing kinase (NIK), the essential kinase mediating noncanonical NF-kappaB activation. Thus, our data demonstrate that inhibition of TRAF3 results in coordinated activation of both NF-kappaB activation pathways.
authors.affiliation: Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA 90095, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Zarnegar
authors.forename: Soh
authors.initials: S
authors.lastname: Yamazaki
authors.forename: Jeannie Q
authors.initials: JQ
authors.lastname: He
authors.forename: Genhong
authors.initials: G
authors.lastname: Cheng
mesh_terms: D000818:Animals; D002460:Cell Line; D051550:I-kappa B Kinase / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000378:metabolism*; D052002:NF-kappa B p50 Subunit / Q000378:metabolism; D052003:NF-kappa B p52 Subunit / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D048008:TNF Receptor-Associated Factor 3 / Q000502:physiology*; D000097782:NF-kappaB-Inducing Kinase
chemical_list: D051550:I-kappa B Kinase; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; D052003:NF-kappa B p52 Subunit; D017346:Protein Serine-Threonine Kinases; D048008:TNF Receptor-Associated Factor 3; D000097782:NF-kappaB-Inducing Kinase; C496564:Chuk protein, mouse