Proinflammatory activation of NF-κB requires an upstream kinase complex (IκB-kinase; IKK)
composed of two catalytic subunits (IKKα and IKKβ) and a noncatalytic regulatory
component named NEMO (NF-κB essentialmodulator). NEMO interacts with a COOH-
terminal sequence within both IKKs termed the NEMO-binding domain (NBD), and a cell-
permeable NBD peptide blocks NEMO/IKKβ interactions and inhibits tumor necrosis factor-α-
induced NF-κB. We report here that a peptide encompassing the NBD not only blocked …