"Animals exhibit behavioral repertoires that are often innate and result in stereotyped sexual and social responses to their environment. Sexual behaviors represent a robust set of innate responses. Genetic studies in Drosophila strongly imply the FruM, a male-specific isoform of the fruitless gene in programming male courtship. The circuit of female behavior on the other has been largely uncharacterized. Here I propose to identify and characterize the neurons involved in female receptivity. I will follow two independent yet complementary approaches: 1) I will use a laser guided neuronal tracing procedure together with electrophysiology to follow to higher order neurons the circuit for sensing the male pheromone cisvaccenyl acetate. cisvaccenyl acetate sensing has common properties at the sensory level in males and females yet it generates different behaviors; 2) I will perform a behavioral screen of lines of flies with different subsets of neurons inhibited for their activity. Once I identify the lines that have a behavioral effect, I will characterize the anatomy, function and connectivity of the subsets of neurons marked in the selected lines. This will be facilitated by the fact these lines allow access to genetic manipulation specifically in the defined subsets of neurons. With this work I expect to contribute to a comprehensive view of the circuits for female sexual behavior. It will allow to determine how much commonality is there between the male and female brain and more importantly to identify general neuronal architectures that guide behavior."