NF-kB p65 is a member of REL-like domain containing protein family, which forms NF-kB complex with the other family members: NF-kappaB1 (p105/p50) or NF-kappaB2 (p100/p52). The NF-kB complex is inactivated and held in the cytoplasm by the NF-kB inhibitor IkB. In response to activation stimuli, IkB kinases (IKKs) phosphorylate IkB, resulting in degradation of IkB and liberation of NF-kB complex. The activated NF-kB complex translocates to the nucleus and binds to kB sites in the DNA of their target genes.