An hsp70 promoter and a 131bp genomic fragment containing the 2F1K sub-region of the IAB7 enhancer cis-regulatory module in the bithorax complex drive expression of Ecol\lacZ.\nAn hsp70 promoter and a 131bp genomic fragment containing the 2F1K sub-region of the IAB7 enhancer cis-regulatory module (containing two ftz and one Kr binding site) in the bithorax complex drive expression of lacZ.