Nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha (IκBα)

IκBα (Nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha) is a key regulatory protein that inhibits the activity of the NF‑κB family of transcription factors by binding to them and sequestering them in the cytoplasm. Upon cellular stimulation by pro-inflammatory signals such as cytokines or pathogens, IκB kinase complexes phosphorylate specific serine residues on IκBα. This phosphorylation marks it for ubiquitination and subsequent degradation via the proteasome. The degradation releases NF‑κB dimers, allowing their translocation into the nucleus where they activate genes involved in immune responses, inflammation, cell proliferation, and survival[1][3][4]. Mutations or dysregulation affecting IκBα can lead to chronic activation of NF‑κB signaling pathways and are implicated in diseases such as cancer (notably Hodgkin's lymphoma), inflammatory conditions, and immune dysfunction[4]. While "IκBα phosphorylation" itself describes a post-translational modification event rather than a discrete molecular entity or drug target per se, it represents a critical regulatory step within this well-characterized signaling axis[1][3]. Note on correctness: "IκBα phosphorylation" refers specifically to a biochemical process rather than an individual molecule/receptor; therefore it is not itself a canonical therapeutic target but rather an event involving the protein "Nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha" (IκBα)[1][3].

Other names

NFKBIANF-kappa-B inhibitor alphaIkappaB-alpha