Protein–protein interactions involving IKKγ (NEMO) that promote the activation of NF‐κB

Abstract

Inhibitor of kappaB kinase (IKK) gamma (IKKgamma), also referred to as nuclear factor kappaB (NF-kappaB) essential modulator (NEMO), is an important regulatory component of the IKK complex. The IKK complex is a signalosome that catalyzes the inducible phosphorylation of IkappaB proteins, which is a key step that leads to the activation of NF-kappaB. The exact functions of IKKgamma (NEMO) as part of the IKK complex have not yet been fully elucidated. This mini-review covers 16 proteins that have been reported to bind to IKKgamma and lead to the enhancement of the activities of the IKK complex, thus resulting in NF-kappaB activation. The major mechanisms by which these interactions are mediated involve the recognition of ubiquitinated upstream signaling components by IKKgamma or the modification of IKKgamma itself by ubiquitination. Additional mechanisms include the sumoylation or phosphorylation of IKKgamma and the modification of the tertiary or quaternary structure of IKKgamma.