13kb fragment that extends from the distal end of the Ubx region in lacZ[UBX.22UZ] to the distal end of the Ubx region in lacZ[UBX.35UZ] fused to Ecol\lacZ coding region via a minimal (non-heat inducible) Hsp70 promoter.
Overexpression of Ubx via a heat shock promoter represses Ecol\lacZ ("Ubx") expression.