Role of adapter function in oncoprotein-mediated activation of NF-kappaB. Human T-cell leukemia virus type I Tax interacts directly with IkappaB kinase gamma.
Mechanisms by which the human T-cell leukemia virus type I Tax oncoprotein activates NF-kappaB remain incompletely understood. Although others have described an interaction between Tax and a holo-IkappaB kinase (IKK) complex, the exact details of protein-protein contact are not fully defined. Here we show that Tax binds to neither IKK-alpha nor IKK-beta but instead complexes directly with IKK-gamma, a newly characterized component of the IKK complex. This direct interaction with IKK-gamma correlates with Tax-induced IkappaB-alpha phosphorylation and NF-kappaB activation. Thus, our findings establish IKK-gamma as a key molecule for adapting an oncoprotein-specific signaling to IKK-alpha and IKK-beta.
Jin
D Y
DY
Laboratory of Molecular Microbiology, NIAID, National Institutes of Health, Bethesda, Maryland 20892-0460, USA.
Giordano
V
V
Kibler
K V
KV
Nakano
H
H
Jeang
K T
KT
D004268:DNA-Binding Proteins / Q000378:metabolism; D016356:Gene Products, tax / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D051550:I-kappa B Kinase; D020672:I-kappa B Proteins; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism*; D015513:Oncogene Proteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D015398:Signal Transduction; D015533:Transcriptional Activation; D014162:Transfection
D004268:DNA-Binding Proteins; D016356:Gene Products, tax; D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D015513:Oncogene Proteins; D000072000:NF-KappaB Inhibitor alpha; D017346:Protein Serine-Threonine Kinases; C496559:CHUK protein, human; D051550:I-kappa B Kinase; C496560:IKBKB protein, human; C496565:IKBKE protein, human