title: A Drosophila protein specific to pheromone-sensing gustatory hairs delays males' copulation attempts.
abstract: In insects, increasing evidence suggests that small secreted pheromone binding proteins (PBPs) and odorant binding proteins (OBPs) are important for normal olfactory detection of airborne pheromones and odorants far from their source. In contrast, it is unknown whether extracellular ligand binding proteins participate in perception of less volatile chemicals, including many pheromones, that are detected by direct contact with chemosensory organs. CheB42a, a small Drosophila melanogaster protein unrelated to known PBPs or OBPs, is expressed and likely secreted in only a small subset of gustatory sensilla on males' front legs, the site of gustatory perception of contact pheromones. Here we show that CheB42a is expressed specifically in the sheath cells surrounding the taste neurons expressing Gr68a, a putative gustatory pheromone receptor for female cuticular hydrocarbons that stimulate male courtship. Surprisingly, however, CheB42a mutant males attempt to copulate with females earlier and more frequently than control males. Furthermore, CheB42a mutant males also attempt to copulate more frequently with other males that secrete female-specific cuticular hydrocarbon pheromones, but not with females lacking cuticular hydrocarbons. Together, these data indicate that CheB42a is required for a normal gustatory response to female cuticular hydrocarbon pheromones that modulate male courtship.
authors.affiliation: Department of Genetics, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
authors.forename: Su K
authors.initials: SK
authors.lastname: Park
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Mann
authors.forename: Heping
authors.initials: H
authors.lastname: Lin
authors.forename: Elena
authors.initials: E
authors.lastname: Starostina
authors.forename: Aaron
authors.initials: A
authors.lastname: Kolski-Andreaco
authors.forename: Claudio W
authors.initials: CW
authors.lastname: Pikielny
mesh_terms: D000818:Animals; D003307:Copulation / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005121:Extremities / Q000033:anatomy & histology / Q000502:physiology; D005260:Female; D049452:Green Fluorescent Proteins / Q000032:analysis; D006838:Hydrocarbons / Q000378:metabolism; D008297:Male; D012724:Sex Attractants / Q000378:metabolism*
chemical_list: C469827:CheB42a protein, Drosophila; D029721:Drosophila Proteins; D006838:Hydrocarbons; D012724:Sex Attractants; D049452:Green Fluorescent Proteins