Figure 4.

NBP and p53 display differential p53RE-binding affinities. (A) Alignments of the p53RE motif 20 mers derived from different p53 responsive promoters (20, 21, 23, 24, 28, 31, 48). Cons., The consensus p53 binding sequence. Asterisks are placed above nucleotides to indicate deviations from the consensus sequence. The dual arrow bars denote the palindrome sequences. (B) NBP exhibits a differential sequence preference distinct from p53. The EMSA was performed as described in Fig. 1B. p53 (40 ng) was used in lanes 2, 4–16. One microliter (≈4 μg of protein) of the H1299 cell nuclear extracts was used in lanes 3–16 as indicated on top. All the nonlabeled oligomer competitors (10 and 30 ng) were used in the lanes as indicated on top.