Identification and purification of a human immunoglobulin-enhancer-binding protein (NF-κB) that activates transcription from a human immunodeficiency virus type 1 promoter in vitro

Abstract

The enhancer-binding factor NF-κB, which is found only in cells that transcribe immunoglobulin light chain genes, has been purified from nuclear extracts of Namalwa cells (human Burkitt lymphoma cell) by sequence-specific DNA affinity chromatography. The purified NF-κB has been identified as a 51-kDA polypeptide by UV-crosslinking analysis. 'Footprint' and methylation-interference analyses have shown that purified NF-αB has a binding activity specific for the κ light chain enhancer sequence. The purified factor activated in vitro transcription of the human immunodeficiency virus type I promoter by binding to an upstream NF-κB-binding site.