文摘
Tumor necrosis factor (TNF) triggers a signaling pathway converging on the activation ofNF-B, which forms the basis for many physiological and pathological processes. In a kinase gene screenusing a NF-B reporter, we observed that overexpression of casein kinase 1 (CK1) enhanced TNF-induced NF-B activation, and a CK1 kinase dead mutant, CK1 (K46A), reduced NF-B activationinduced by TNF. We subsequently demonstrated that CK1 interacted with receptor interacting protein1 (RIP1) but not with TRADD, TRAF2, MEKK3, IKK, IKK, or IKK in mammalian cells. RIP1 is anindispensable molecule in TNF/NF-B signaling. We demonstrated that CK1 interacted with andphosphorylated RIP1 at the intermediate domain. Finally, we showed that CK1 enhanced RIP1-mediatedNF-B activation. Taken together, our studies suggest that CK1 is another kinase that regulates RIP1function in NF-B activation.
