fruitless tunes functional flexibility of courtship circuitry during development

Drosophila male courtship is controlled by the male-specific products of the fruitless (fru(M)) gene and its expressing neuronal circuitry. fru(M) is considered a master gene that controls all aspects of male courtship. By temporally and spatially manipulating fru(M) expression, we found that fru(M) is required during a critical developmental period for innate courtship toward females, while its function during adulthood is involved in inhibiting male-male courtship. By altering or eliminating fru(M) expression, we generated males that are innately heterosexual, homosexual, bisexual, or without innate courtship but could acquire such behavior in an experience-dependent manner. These findings show that fru(M) is not absolutely necessary for courtship but is critical during development to build a sex circuitry with reduced flexibility and enhanced efficiency, and provide a new view about how fru(M) tunes functional flexibility of a sex circuitry instead of switching on its function as conventionally viewed.

Automated summary

Research has shown that Drosophila male courtship is controlled by the fru(M) gene, with a critical role during development in building a sex circuitry. Manipulating fru(M) expression has resulted in flies with different sexual orientations, highlighting the gene's importance in shaping innate courtship behaviors.