Transgenic construct used in a study to characterize a pairing-sensitive element in the eve 3' boundary region. Contains a 5' sub-portion of the 300bp 'PRE300' fragment containing an active portion of a pairing-sensitive element near eve (PRE300 fragment extends from +8.9kb to +9.2kb relative to the eve transcription start site), inserted upstream of the gl binding sites present in w+mCG.