IúBñ (<u>n</u>uclear <u>f</u>actor of <u>k</u>appa light polypeptide gene enhancer in <u>B</u>-cells <u>i</u>nhibitor <u>a</u>lpha; NFKBIA) is one member of a family of cellular proteins that function to inhibit the NF-úB transcription factor. IúBñ inhibits NF-úB by masking the nuclear localization signals (NLS) of NF-úB proteins and keeping them sequestered in an inactive state in the cytoplasm. In addition, IúBñ blocks the ability of NF-úB transcription factors to bind to DNA, which is required for NF-úB's proper functioning.
The gene encoding the IúBñ protein is mutated in some Hodgkin's lymphoma cells; such mutations inactivate the IúBñ protein, thus causing NF-úB to be chronically active in the lymphoma tumor cells and this activity contributes to the malignant state of these tumor cells.
IúBñ has been shown to interact with: