NF-κB activity in Tax transgenic mouse tumors.

Nuclear extracts were prepared from Tax transgenic tissues, and representative results from 3 animals (#524, #542, and #579) are shown. Tissues used included tumors arising on the nose, leg, or foot, as well as spleens with tumor involvement or uninvolved heart tissue. Electrophoretic mobility gel-shift assays were performed in the absence or presence of 100-fold excess of unlabeled oligonucleotide (indicated as “+ Cold Oligo”). The positions of the retarded NF-κB-DNA bands are indicated by the arrows on the left, indicating the positions of DNA bound to the p65-p50 heterodimer and p50-p50 homodimer of NF-κB.