Transgenic construct used to study the properties of the bxd Polycomb response element (bxdPRE) from the Ubx gene. Generated by inserting 4 copies of the 77bp PF (PstI/HinfI) fragment of the bxdPRE into the CaSpeR4 vector (which contains the w+mC minigene).
construct_comment: Activity of UbxPRE assayed by monitoring white expression.