Gel mobility shift assays were performed using a radiolabeled DNA fragment comprising the AdMLP in the presence of TBP alone, TBP, and TFIIA and TBP, TFIIA and various fragments of RAP74 (RAP74-(1–517;wt), RAP74-(1–75), RAP74-(1–136), RAP74-(363–409), and RAP74-(363–444)). The positions of the TBP (T), TBP-TFIIA (T-A), and TBP-TFIIA-RAP74 (T-A-RAP74) complexes and that of the free probe are indicated.