Ubx cooperatively binds multimers of Hox binding sites (TAAT/ATTA, red text), including enhancers for the ubx and antp genes [76]. Other transcription factors are not known to influence Ubx binding to these sites. In the second category, DNA binding sites for Ubx monomers are separated by DNA binding sites for other transcription factors (Medea, purple text, and Mad, green text) [91]. Regulation of the sal gene is coordinated by both Ubx and BMP signaling, which controls the activity of Medea and Mad. In the final category, Ubx binds DNA and regulates transcription in association with Exd (blue text) and Hth (orange text), general Hox co-factors [92], [93]. The positions of the DNA sequences are marked in bp relative to the start of transcription.