Control of NF-κB activation by the COP9 signalosome

The transcription factor NF-κB (nuclear factor κB) exerts crucial functions in the regulation of innate and adaptive immune responses, wound healing and tissue maintenance and in the development of immune cells. Tight control of NF-κB is essential for an efficient defence against pathogens and environmental stress to protect organisms from inflammatory diseases including cancer. An involvement of the CSN (COP9 signalosome) in the regulation of NF-κB has been discovered recently. The CSN is a conserved multiprotein complex, which mainly functions in the control of proteolysis. Here, we review recent observations indicating important roles of the CSN in the control of NF-κB in innate immunity, as well as T-cell activation and maturation.