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Hierarchical chemosensory regulation of male-male social interactions in Drosophila

Division of Biology, California Institute of Technology, Pasadena, California, USA.
Nature Neuroscience (Impact Factor: 14.98). 06/2011; 14(6):757-62. DOI: 10.1038/nn.2800
Source: PubMed

ABSTRACT Pheromones regulate male social behaviors in Drosophila, but the identities and behavioral role(s) of these chemosensory signals, and how they interact, are incompletely understood. We found that (z)-7-tricosene, a male-enriched cuticular hydrocarbon that was previously shown to inhibit male-male courtship, was essential for normal levels of aggression. The mechanisms by which (z)-7-tricosene induced aggression and suppressed courtship were independent, but both required the gustatory receptor Gr32a. Sensitivity to (z)-7-tricosene was required for the aggression-promoting effect of 11-cis-vaccenyl acetate (cVA), an olfactory pheromone, but (z)-7-tricosene sensitivity was independent of cVA. (z)-7-tricosene and cVA therefore regulate aggression in a hierarchical manner. Furthermore, the increased courtship caused by depletion of male cuticular hydrocarbons was suppressed by a mutation in the olfactory receptor Or47b. Thus, male social behaviors are controlled by gustatory pheromones that promote aggression and suppress courtship, and whose influences are dominant to olfactory pheromones that enhance these behaviors.

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Available from: Tetsuya Miyamoto, Mar 28, 2014
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    • "These data suggest that feminization of pheromone-sensing neurons can affect other classes of gustatory receptor neurons, possibly via indirect mechanisms. These data also further support the possible sensory crosstalk between canonical taste sensory pathways and the pheromonal input pathways as has been shown for the bitter receptors Gr66a, Gr33a, and Gr32a (Koganezawa et al., 2010; Lacaille et al., 2009; Miyamoto and Amrein, 2008; Moon et al., 2009; Wang et al., 2011). Previously, we have shown that sexually-dimorphic ppk23- expressing neurons represent the primary fru-expressing GRNs in the male appendages (Lu et al., 2012). "
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    01/2014; 3(2). DOI:10.1242/bio.20147369
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    • "Drosophila males have developed complementary olfactory strategies to find their mates, based on inhibiting and/or stimulating olfactory signals. Enhancing olfactory cues for male courtship appears to be highly context-dependant (Grosjean et al., 2011; Wang et al., 2011). It would be very useful to know more about the integration process happening within male brains to compare sensory stimuli of different nature (olfactory, gustatory, auditory, visual). "
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    Frontiers in Physiology 04/2013; 4:72. DOI:10.3389/fphys.2013.00072 · 3.50 Impact Factor
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    • "7T and cVA are inhibitory compounds on males and 7,11-HD, and 7,11-ND are excitatory compounds on females (Ferveur, 2005; Jallon, 1984). 7P is abundant on males, with more complex roles in courtship (Ferveur, 2005; Jallon, 1984; Wang et al., 2011). Δppk23, Δppk29 and control males were paired with oe-males painted with 7T, 7P or cVA. "
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