Inhibits NF-kappa-B by complexing with and trapping it in the cytoplasm. However, the unphosphorylated form resynthesized after cell stimulation is able to bind NF-kappa-B allowing its transport to the nucleus and protecting it to further NFKBIA-dependent inactivation. Association with inhibitor kappa B-interacting NKIRAS1 and NKIRAS2 prevent its phosphorylation rendering it more resistant to degradation, explaining its slower degradation.
Specificity
Natural and recombinant Rat NF-kappa-B inhibitor beta
Interacts with COMMD1 and inhibitor kappa B-interacting Ras-like NKIRAS1 and NKIRAS2 (By similarity). Interacts with THRB (via ligand-binding domain). Interacts with RELA and REL.