Binding of nuclear proteins from Dami cells to oligonucleotides (residues −65 to −38) containing Sp1/Sp3 sites A and B.

Nuclear extracts were prepared from Dami cells and incubated with radiolabeled oligonucleotides (Table 2) either in the absence of antiserum (lanes 1-4) or following incubation with anti-Sp1 (lanes 5, 6, 14, 15), anti-Sp3 (lanes 7-9), anti-AP2 (lanes 10, 11), or anti-NFκB (lanes 12, 13). The radiolabeled nucleotide probes (Table2) were −52C (“C”), −52T (“T”), B, and A, as indicated at the top of each lane. The positions of complexes I, II, and III are indicated to the left of the gel. Asterisks denote supershifted complexes. The samples in lanes 14 and 15, preincubated with anti-SP1, were treated in the same experiment as those depicted in lanes 10-13.