title: Postmating Circuitry Modulates Salt Taste Processing to Increase Reproductive Output in Drosophila.
abstract: To optimize survival and reproduction, animals must match their nutrient intake to their current needs. Reproduction profoundly changes nutritional requirements, with many species showing an appetite for sodium during reproductive periods. How this internal state modifies neuronal information processing to ensure homeostasis is not understood. Here, we show that dietary sodium levels positively affect reproductive output in Drosophila melanogaster; to satisfy this requirement, females develop a strong, specific appetite for sodium following mating. We show that mating modulates gustatory processing to increase the probability of initiating feeding on salt. This postmating effect is not due to salt depletion by egg production, since abolishing egg production leaves the sodium appetite intact. Rather, the salt appetite is induced need-independently by male-derived Sex Peptide acting on the Sex Peptide Receptor in female reproductive tract neurons. We further demonstrate that postmating appetites for both salt and yeast are driven by the resultant silencing of downstream SAG neurons. Surprisingly, unlike the postmating yeast appetite, the salt appetite does not require octopamine, suggesting a divergence in the postmating circuitry. These findings demonstrate that the postmating circuit supports reproduction by increasing the palatability of specific nutrients. Such a feedforward regulation of sensory processing may represent a common mechanism through which reproductive state-sensitive circuits modify complex behaviors across species.
authors.affiliation: Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal.
authors.forename: Samuel James
authors.initials: SJ
authors.lastname: Walker
authors.affiliation: Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal.
authors.forename: Verónica María
authors.initials: VM
authors.lastname: Corrales-Carvajal
authors.affiliation: Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal. Electronic address: carlos.ribeiro@neuro.fchampalimaud.org.
authors.forename: Carlos
authors.initials: C
authors.lastname: Ribeiro
mesh_terms: D000818:Animals; D001066:Appetite; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000502:physiology*; D005260:Female; D008297:Male; D010058:Oviposition; D010455:Peptides / Q000378:metabolism; D018000:Receptors, Peptide; D012982:Sodium, Dietary / Q000378:metabolism*; D013649:Taste
chemical_list: D029721:Drosophila Proteins; D010455:Peptides; D018000:Receptors, Peptide; D012982:Sodium, Dietary; C526291:sex peptide receptor, Drosophila