Role of Adapter Function in Oncoprotein-mediated Activation of NF-κB HUMAN T-CELL LEUKEMIA VIRUS TYPE I Tax INTERACTS DIRECTLY WITH IκB KINASE γ

摘要: 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 and a holo-IkappaB kinase (IKK) complex, exact details of protein-protein contact are not fully defined. Here we show that binds to neither IKK-alpha nor IKK-beta but instead complexes directly with IKK-gamma, newly characterized component IKK complex. This direct IKK-gamma correlates Tax-induced IkappaB-alpha phosphorylation activation. Thus, our findings establish as key molecule for adapting oncoprotein-specific signaling IKK-beta.