Article

A cytokine-responsive IkappaB kinase that activates the transcription factor NF-kappaB.

Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, University of California at San Diego, La Jolla 92093-0636, USA.
Nature (Impact Factor: 42.35). 09/1997; 388(6642):548-54. DOI: 10.1038/41493
Source: PubMed

ABSTRACT Nuclear transcription factors of the NF-kappaB/Rel family are inhibited by IkappaB proteins, which inactivate NF-kappaB by trapping it in the cell cytoplasm. Phosphorylation of IkappaBs marks them out for destruction, thereby relieving their inhibitory effect on NF-kappaB. A cytokine-activated protein kinase complex, IKK (for IkappaB kinase), has now been purified that phosphorylates IkappaBs on the sites that trigger their degradation. A component of IKK was molecularly cloned and identified as a serine kinase. IKK turns out to be the long-sought-after protein kinase that mediates the critical regulatory step in NF-kappaB activation.

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