UASt regulatory sequences drive expression of a full length ebo cDNA clone (SD03282).

Expression of two copies of Exp6^Scer\UAS.cTa in the R3 and R4d ring neurons under the control of Scer\GAL4^Aph-4-c232 rescues the visual orientation memory loss seen in Exp6^ebo-678 mutant flies. No rescue is seen when only one copy of Exp6^Scer\UAS.cTa is expressed. Rescue is also seen when Exp6^Scer\UAS.cTa is expressed under the control of Scer\GAL4^c305a (R2 and R4d ring neurons), Scer\GAL4^198Y (R1), Scer\GAL4^lilli-189Y (R3), Scer\GAL4^EB1 (R2), Scer\GAL4^ftz.ng (R4) or Scer\GAL4^A19 (R4m).

Exp6^ebo-678/Y mutant flies expressing Exp6^Scer\UAS.cTa under the control of a temperature sensitive Scer\GAL4^hs.PU driver show wild type memory behaviour and have an intact ellipsoid body neuropil when raised at the permissive temperature of 25[o]C. When raised at 18[o]C (the restrictive temperature) the flies do not show any visual orientation memory. However when these flies are shifted back to the permissive temperature and tested again the following day visual orientation memory is intact. 40% of these flies show ellipsoid body defects. When Exp6^ebo-678/Y mutant flies expressing Exp6^Scer\UAS.cTa under the control of Scer\GAL4^hs.PU are raised at 25[o]C, but transferred to 18[o]C for 72hrs shortly after eclosion, the flies have defective visual orientation memory. Some, but not all, of these flies show ellipsoid body defects.

Expression of Exp6^Scer\UAS.cTa under the control of either Scer\GAL4^c305a or Scer\GAL4^lilli-189Y and restricted to the adult stages using Scer\GAL80^ts.αTub84B is unable in rescue of the visual orientation phenotype seen in Exp6^ebo-678 mutant flies. If the flies are then shifted to the restrictive temperature overnight and retested the phenotype is no longer seen.

Expression of one copy of Exp6^Scer\UAS.cTa under the control of Scer\GAL4^Cha.7.4 fully rescues the visual orientation memory defects seen in Exp6^ebo-678 mutant flies. The same is seen when two copies of Exp6^Scer\UAS.cTa are expressed under the control of Scer\GAL4^Gad1.3.098. Both drivers are also able to rescue the histological ellipsoid body defects.