Claim: The NFKB complex is inhibited by I-kappa-B proteins, phosphorylation of the serine residues of which by kinases marks them for destruction via the ubiquitination pathway, thereby allowing activation of the NF-kappa-B complex.
Evidence: The NFKB complex is inhibited by I-kappa-B proteins (NFKBIA, MIM 164008, or NFKBIB), which inactivate NF-kappa-B by trapping it in the cytoplasm. Phosphorylation of serine residues on the I-kappa-B proteins by kinases (IKBKA, MIM 600664 or IKBKB, MIM 603258) marks them for destruction via the ubiquitination pathway, thereby allowing activation of the NF-kappa-B complex.