FIG. 3.

ATF1 and CREB from HeLa nuclear extracts bind to the c-Jun ATF site. Gel mobility assays were performed with HeLa cell nuclear extracts and a ³²P-labeled double stranded oligonucleotide spanning the c-jun ATF site as a probe. A 50-fold molar excess of unlabeled oligonucleotide (jATF) was included as a specific competitor as indicated. Other nonspecific oligonucleotides had no effect (data not shown). The addition of antisera to the indicated proteins is shown. NRS, normal rabbit serum; −, no serum added. The arrows indicate the DNA-protein complexes obtained.