Fruitless decommissions regulatory elements to implement cell-type-specific neuronal masculinization

In the fruit fly Drosophila melanogaster , male-specific splicing and translation of Fruitless transcription factor (Fru M ) alters presence, anatomy, and/or connectivity >60 types central brain neurons that interconnect to generate male-typical behaviors. While indispensable function Fru in sex-specific behavior has been understood for decades, molecular mechanisms underlying its activity remain unknown. Here, we take a genome-wide, brain-wide approach identifying regulatory elements whose depends on presence . We identify 436 high-confidence genomic regions differentially accessible male fruitless neurons, validate candidate as bona fide, regulated enhancers, describe particular cell which these enhancers are active. find individual not activated universally but dedicated specific fru + types. Aside from itself, genes or common across circuit; rather, appears masculinize each type differently, by tweaking expression same effector used other circuits. Finally, motifs enriched among open female closed male. Together, results suggest acts cell-type-specifically decommission neurons.