Figure 4.

Three putative transcription factor binding sites form DNA–protein complexes in neocortical nuclear extracts. Neocortical nuclear extracts from E18 rat embryos were incubated with three ³²P-radiolabeled probes from human GABRB1, GABRD and GABRB3. Cold wild-type oligonucleotides were used to define specificity through competition. Cold oligonucleotides were added at 100-fold excess over probe. The conditions for each lane are as indicated. Specific binding complexes are shown using asterisks (*). The probe sequences are as follows: (A) GABRB1: AATACGGTCCCTACT, (B) GABRD: ACTTAATTTGATTCCAT and (C) GABRB3: CGTGCCGGGGCGCGGCGGA.