p-IκB-α Antibody (Tyr 42): sc-101714

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On the basis of both functional and structural considerations, members of the I˚B family of proteins can be divided into four groups. The first of these groups, I˚B-å, includes the avian protein pp40 and the mammalian MAD-3, both of which inhibit binding of p50–p65 NFkB complex or Rel protein to their cognate binding sites but do not inhibit the binding of p50 homodimer to ˚B sites, suggesting that the I˚B-å family binds to the p65 subunit of p50–p65 heterocomplex through ankyrin repeats. The second member of the I˚B family is represented by a protein designated I˚B-∫. The third group of I˚B proteins is represented by I˚B-©, a protein identical in sequence with the C-terminal domain of the p110 precursor of NFkB p50 and expressed predominantly in lymphoid cells. An additional I˚B family member has been identified as I˚B-e, a protein which has several phosphorylated forms and is primarily found complexed with Rel A and/or c-Rel. There is a consensus phosphorylation site for CKII between residues 269-299, and within this range there are three phosphorylation sites that important for constitutive phosphorylation and intrinsic stability of I˚B-å: Ser 283, Thr 291 and Thr 299.