Transgenic construct used to study the Fab-7 Polycomb Group response element (PRE) from the Bithorax complex. Derived from P{UAS-lacZ.U/l5}, which contains the Ecol\lacZC4.UAS reporter and a w+mC marker. Contains: a 3.7kb HindIII fragment carrying Fab-7 (from position +122 to +126 on the BXC map) - the Ecol\lacZUAS.l5 reporter - a second copy of the 3.7kb Fab-7 fragment - the w+mC marker. The Fab-7 PRE sequence upstream of Ecol\lacZUAS.l5 is oriented such that the distal end of the element is closest to the UAS sequences of the Ecol\lacZUAS.l5 reporter. The Fab-7 PRE sequence downstream of Ecol\lacZUAS.l5 is oriented such that the proximal end of the sequence is closest to the 3' end of the Ecol\lacZUAS.l5 reporter.