Nuclear factor NF-kappa-B p105/p50 subunit (NFKB1) is a pleiotropic transcription factor which is present in almost all cell types and is involved in many biological processes such as inflammation, immunity, differentiation, cell growth, tumorigenesis and apoptosis. NF-kappa-B is a homo- or heterodimeric complex formed by the Rel-like domain-containing proteins RelA/p65, RelB, NFKB1/p105, NFKB1/p50, Rel and NFKB2/p52. Homo- and heterodimers bind with different affinities at kappa-B sites in the DNA of their target genes.The synthetic peptide used to raise the antibody Cat. No. 200173 is selected from a sequence within the C-term region of human NFKB p105/p50. For blocking experiments, a 10 to 100 fold molar excess to antibody is recommended.