UAS sequences drive expression of a fusion protein composed of the Hsap\APP coding sequence, nuclear localization sequence (Tag:NLS(SV40-largeT)) and a lexA::VP16 driver sequence. The protein is also tagged at the end with a Tag:MYC epitope. This protein acts as a reporter of processing of Hsap\APP in vivo. In the absence of processing the lexA::VP16 driver is tethered to the membrane by Hsap\APP. Upon processing of Hsap\APP by α-secretase and Presenilin, a protein fragment containing the nuclear localization sequence and lexA::VP16 driver is released, which is then able to translocate to the nucleus and drive expression of a lexAop-driven reporter transgene.