Background information
Pro inflammatory cytokines activate the transcription factor NF kappa B by stimulating the activity of a protein kinase that phosphorylates Ikappa B, an inhibitor of NF kappa B, at sites that trigger its ubiquitination and degradation. A large, cytokine responsive Ikappa B kinase (IKK) complex has been purified and the genes encoding 2 of its subunits have been cloned. These subunits, IKK alpha and Ikk beta, are protein kinases whose function is needed for NF kappa B activation by pro inflammatory stimuli. IKK is composed of similar amounts of IKK alpha, Ikk beta, which are differentially processed forms of a third subunit, IKK gamma. IKK gamma interacts preferentially with IKK beta and is required for the activation of the IKK complex.
