Neural sex modifies the function of a C. elegans sensory circuit.
Though sex differences in animal behavior are ubiquitous, their neural and genetic underpinnings remain poorly understood. In particular, the role of functional differences in the neural circuitry that is shared by both sexes has not been extensively investigated. We have addressed these issues with C. elegans olfaction, a simple innate behavior mediated by sexually isomorphic neurons. Though males respond to the same olfactory attractants as do hermaphrodites, we find that each sex has a characteristic repertoire of olfactory preferences. These are not secondary to other sex-specific behaviors and do not require signaling from the gonad. Sex-specific olfactory preferences are controlled by tra-1, the master regulator of C. elegans sexual differentiation. Moreover, the genetic masculinization of neurons in an otherwise wild-type hermaphrodite is sufficient to switch the sexual phenotype of olfactory preference behavior. These studies reveal novel and unexpected sex differences in a C. elegans sensory behavior that is exhibited by both sexes. Our results indicate that these differences are a function of the chromosomally determined sexual identity of shared neural circuitry.
Lee
Kyunghwa
K
Interdepartmental Graduate Program in Neuroscience, University of Rochester, Rochester, New York 14642, USA.
Portman
Douglas S
DS
D000818:Animals; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000502:physiology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology; D012734:Disorders of Sex Development; D005260:Female; D008297:Male; D009474:Neurons / Q000502:physiology; D012727:Sex Characteristics; D012903:Smell; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology
D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins; D014157:Transcription Factors; C121025:tra-1 protein, C elegans