ScerGAL4Ir52a.PK drives expression in leg taste bristles of the tibia and tarsus. In males more cells of the tarsal segments 2 and 4 express ScerGAL4Ir52a.PK than in females. Labeled axonal projections from the prothoracic legs cross the midline in males but not in females where expression is also fainter.
Photogenetic inactivation of Ir52a-positive neurons by Scer\GAL4Ir52a.PK-driven expression of Gthe\ACR1UAS.d.EYFP under red light and in the presence of all-trans-retinal leads to impaired courtship behavior in males (fewer individuals initiate courtship behavior, i.e. wing extension, towards virgin females and fewer achieve successful copulation with virgin females) and to decreased copulation in females, as compared to controls.
Photogenetic activation of Ir52a-positive neurons by Scer\GAL4Ir52a.PK-driven expression of Cnoc\ChR1Cs.IVS.20xUAS.Venus under red light and in the presence of all-trans-retinal leads to males showing increased male-to-male and even cross-species (D.mel male x D.suz female) courtship behavior, as compared to controls; this phenotype is not observed in the absence of a target fly. In females, this neuronal activation leads to decreased refractoriness to re-mating, as compared to controls.
