The IκB Kinase Complex (IKK) Contains Two Kinase Subunits, IKKα and IKKβ, Necessary for IκB Phosphorylation and NF-κB Activation

@article{Zandi1997TheIK,
  title={The I$\kappa$B Kinase Complex (IKK) Contains Two Kinase Subunits, IKK$\alpha$ and IKK$\beta$, Necessary for I$\kappa$B Phosphorylation and NF-$\kappa$B Activation},
  author={Ebrahim Zandi and David M. Rothwarf and Mireille Delhase and Makio Hayakawa and Michael Karin},
  journal={Cell},
  year={1997},
  volume={91},
  pages={243-252}
}
Recently we purified a 900 kDa cytokine-responsive IkappaB kinase complex (IKK) and molecularly cloned one of its subunits, IKKalpha, a serine kinase. We now describe the molecular cloning and characterization of IKKbeta, a second subunit of the IKK complex. IKKbeta is 50% identical to IKKalpha and like it contains a kinase domain, a leucine zipper, and a helix-loop-helix. Although IKKalpha and IKKbeta can undergo homotypic interaction, they also interact with each other and the functional IKK… Expand

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