NFKB Repressing Factor (NKRF)

NKRF encodes a transcription factor that interacts with specific negative regulatory elements (NREs) to mediate transcriptional repression of certain NK-kappa-B-responsive genes. The protein localizes predominantly to the nucleolus with a small fraction found in the nucleoplasm and cytoplasm.The deduced 388-amino acid protein has a calculated molecular mass of 43.8 kD and contains an N-terminal nuclear localization signal. The C-terminal 92 amino acids of NRF constitute the DNA-binding domain, which has 4 turns and 4 alpha helices, similar to a winged helix-turn-helix DNA-binding motif. Northern blot analysis detected ubiquitous expression of 3.7- and 4.0-kb transcripts that differ in their 3-prime untranslated regions. The longer transcript predominated in most tissues, but the 3.7-kb transcript predominated in brain.