FIG. 7.

Mapping of the Elba recognition sequence in probe 5-4. Labeled 5-4 DNA was incubated with nuclear extracts from 0- to 12-h embryos in the presence of a 100-fold excess of cold competitor DNA as indicated. DNAs used as cold competitors are diagramed below. The sequence for the top (T) strand (5′ [proximal] to 3′ [distal]) of probe 5-4 is shown. For 3-bp mutations, the changes in the DNA sequence are given below the corresponding bases of 5-4. The rule for changing bases was the same as that described in the legend to Fig. 4. Bold lines delineate the positions of the truncated DNAs. The 8-bp core recognition sequence and the flanking sequences in the top strand of probe 5-4 that contribute to efficient binding in the EMSA experiment are bracketed.