UASt regulatory sequences drive expression of an inverted repeat.
flightless, with Scer\GAL4Mef2.PR
viable, with Scer\GAL4Mef2.PR
viable, with Scer\GAL4pnr-MD237
Depending on the insertion line used, expression under the control of Scer\GAL4Mef2.PR can result in flightless flies.