activated IKKs phosphorylates IkB alpha causing the NFkB complex to dissociate from the phospho-IkB

Stable Identifier
Reaction [transition]
Gallus gallus
Locations in the PathwayBrowser
SVG |   | PPTX  | SBGN
Click the image above or here to open this reaction in the Pathway Browser
The layout of this reaction may differ from that in the pathway view due to the constraints in pathway layout

The phosphorylation and ubiquitination of IkB kinase complex is mediated by two distinct pathways, either the classical or alternative pathway. In the classical NF-kB signaling pathway, the activated IKK complex, predominantly acting through IKK beta in an IKK gamma-dependent manner, catalyzes the phosphorylation of IkBs (at sites corresponding to Ser32 and Ser36 of human IkB-alpha or Ser19 and Ser22 of human IkB-beta), polyubiquitination (at sites corresponding to Lys21 and Lys22 of human IkB-alpha) and subsequent degradation by the 26S proteasome. The K-48 ubiquitination is mediated by the E2 ubiquitin ligases (or SCFs) formed by three subunits: Skp1, Cul A (Cdc53), and one of many F-box proteins.

Chicken IkB-alpha shows 71% identity to the human IkB alpha kinase. Multiple sequence alignment of the human and chicken IKB-alpha showed that chicken Ser36 and Ser40 correspond to human Ser32 and Ser 36 mentioned above.

There is insufficient data for chicken IkB beta to make a comparison with other species.

Literature References
PubMed ID Title Journal Year
17047224 Regulation and function of IKK and IKK-related kinases

Karin, M, Hacker, H

Sci STKE 2006
Catalyst Activity

protein serine/threonine kinase activity of activated IKKs complex [cytosol]

Inferred From
Cite Us!