The Drewell lab has been very successful in characterizing the minimal enhancer region for many Hox genes such as IAB7b in Drosophila. However, understanding the architecture and function of these enhancer regions is much more difficult.
Working in collaboration, we have developed a simple thermodynamic-based model of the IAB7b enhancer. This model has led to clues regarding FTZ-FTZ homotypic cooperativity, as well as repression by KR and GT through both quenching and competition. The model has also been able to successfully predict the qualitative expression of transgenic embryos containing IAB7b mutant constructs.