NEMO recognition of ubiquitinated Bcl10 is required for T cell receptor-mediated NF-κB activation
Abstract
The mechanism by which the Carma1-Bcl10-MALT1 (CBM) complex couples T cell antigen receptor (TCR) signaling to IκB kinase (IKK) and NF-κB activation is not known. Here, we show that Bcl10 undergoes K63-linked polyubiquitination in response to T cell activation and subsequently binds NEMO, the regulatory subunit of IKK. This interaction requires the ubiquitin-binding activity of NEMO. The sites of Bcl10 ubiquitination were mapped to K31 and K63. Mutation of these residues did not affect TCR signaling-induced CBM complex assembly but prevented Bcl10 ubiquitination, NEMO binding, and NF-κB activation. Therefore, the regulated ubiquitination of Bcl10 and its recognition by NEMO are a critical link between the CBM complex, IKK recruitment, and NF-κB activation.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- February 2008
- DOI:
- 10.1073/pnas.0712313105
- Bibcode:
- 2008PNAS..105.3023W
- Keywords:
-
- Iκ
- B kinase;
- T cell signaling;
- ubiquitination;
- Biological Sciences:Immunology