Effect of p65 expression, TSA and TNF-α treatment on EMSA of the KB site. An oligonucleotide corresponding to the JCV NCCR KB element was used to perform EMSA using nuclear extracts from untreated cells (Control) or cells transfected with expression vector for p65, treated with TSA overnight or with TNF-α for 30 min as described in Methods. For supershifts, antibody to p65 (αp65) or nonimmune rabbit serum (NRS) was added as indicated. Competitor – excess unlabelled probe was added. Unbound probe (loaded alone in lane 1) runs near the bottom of the gel (Position 4).