Inhibitor of nuclear factor kappa-B kinase subunit gamma (IKK-γ (also known as NEMO))

Inhibitor of nuclear factor kappa-B kinase subunit gamma (IKK-gamma, also known as NEMO) is a regulatory scaffold protein encoded by the IKBKG gene. It is an essential component of the IκB kinase (IKK) complex—alongside catalytic subunits IKK-alpha and IKK-beta—which mediates signal-induced activation of the transcription factor NF-kappa-B. Upon stimulation by pro-inflammatory cytokines or other signals, NEMO/IKK-gamma facilitates assembly and activation of the kinase complex through interactions with polyubiquitin chains on upstream signaling molecules. This leads to phosphorylation-induced degradation of IkappaB proteins that normally sequester NF-kappa-B in the cytoplasm. The released NF-kappa-B then translocates into the nucleus where it regulates genes controlling inflammation, immunity, cell survival/apoptosis, and development. Genetic mutations affecting NEMO/IKK-gamma cause syndromes such as anhidrotic ectodermal dysplasia with immunodeficiency due to defective immune responses and abnormal development. Dysregulation or constitutive activity within this pathway has been implicated in cancer progression and chronic inflammatory diseases. While several drugs target components upstream or within this pathway for anti-inflammatory or anticancer effects—including experimental inhibitors like SAR113945—direct pharmacological targeting specific only to NEMO/IKK-gamma remains under investigation because inhibition can compromise host defense mechanisms.

Other names

NF-kappa-B essential modulatorNEMOIKK-gammaIKBKG (gene symbol)Inhibitor of kappaB kinase gamma

Drugs that inhibit the IKK complex block phosphorylation and degradation of IkappaB proteins, thereby preventing activation and nuclear translocation of NF-kappa-B transcription factors. This leads to reduced expression of genes involved in inflammation, immunity, cell survival, and proliferation.