Fig. 2.

Specific binding of Mth and Mma Lrp to the consensus UAS of the rb2 promoter. The DNA probe, 5′-end-labeled on the nontranscribed (nontemplate) strand, was incubated at 55°C (A) or 37°C (B) for 20 min in the absence of Lrp (lane 3 of each panel) or with increasing concentrations of Mth Lrp (A) or Mma Lrp (B) (indicated above each panel and specified throughout for the monomer) and subjected to ·OH cleavage for 30 s at the same temperature. ·OH cleavage products within the T/A box and the two Ptr2 consensus binding sites are boxed in lane 3 and identified at the left of each panel. Also shown are the untreated DNA probe (P) and G and A + G chemical-sequencing ladders.