Approximately 32% of wild-type females expressing fruMB.Scer\UAS.cSa under the control of Scer\GAL4fru.16 develop on average two ectopic `male' serotonergic neurons, sending projections into the abdominal nerve trunk. Ectopic serotonergic terminals innervated the female internal reproductive organs, mostly the calyx of the ovaries but also, more rarely, the uterus and the base of the spermathecae. These serotonergic terminals are never present in virgin or fertilised wild-type females. The ectopic serotonergic neurons and their associated terminalia are analogous to those innervating the male reproductive organs.
The Fas2-positive and BP102-positive axon tracts in the central nervous system are defective in virtually all fruw12/frusat15 embryos which are expressing fruMC.Scer\UAS.cSa under the control of Scer\GAL4sca-537.4.
fruMC.UAS.cSa/Scer\GAL4fru.16 fails to rescue fru3
Expression of fruMC.Scer\UAS.cSa, under the control of Scer\GAL4fru.16 in a fru3/fru3 background does not restore male fertility.
Expression of fruMC.Scer\UAS.cSa under the control of Scer\GAL4fru.16 in fru3 homozygotes and fru3/fruΔC transheterozygotes rescues the formation of the muscle of Lawrence in the male.
Extension of mating length beyond normal duration in fruΔC/fru3 males is rescued by targeted expression of fruMC.Scer\UAS.cSa via Scer\GAL4fru.16.
Expression of fruMC.Scer\UAS.cSa, under the control of Scer\GAL4fru.16 in a fru3 homozygote does not restore male fertility. However, expression of fruMC.Scer\UAS.cSa, under the control of Scer\GAL4fru.16 in a fruΔC/fru3 background, increases the percentage of fertile males from 33% to 78%.
During a 6 hour observation, fruΔC/fru3 males do not mate, whereas approximately 50% of fruΔC/fru3 males expressing fruMC.Scer\UAS.cSa do. These males are slower to initiate mating, although the duration of copulation is similar to that of wild-type males. A small number of control flies (i.e. fruMC.Scer\UAS.cSa/+ ; fruΔC/fru3) manage to mate within the same time as the 'rescued' males, probably due to 'leakage' of the transgene, although mating durations are still significantly longer than those of wild-type males.