NF-kappa B protein purification from bovine spleen: nucleotide stimulation and binding site specificity.

Abstract

The activity of the enhancer for the .kappa. immunoglobulin light chain gene critically depends on the presence in the nucleus of the NF-.kappa.B protein. We purified NF-.kappa.B over 50,000-fold and identified two protein species, 42 and 44 kDa, that could be eluted and renatured from a sodium dodecyl/sulfate/polyacrylamide gel to give specific DNA-binding activity. Binding of the purified bovine NF-.kappa.B as well as that from human and murine B- or T-lymphoid cell extracts was dramatically stimulated by nucleoside triphosphates. The effect distinguished NF-.kappa.B from a related factor, H2-TF1. Purified NF-.kappa.B interacted efficiently with regulatory sequences that function during either B- or T-lymphocyte activation, including the human immunodeficiency virus enhancer and a NF-.kappa.B binding site we detected in the interleukin 2 enhancer.