Article

Hierarchical chemosensory regulation of male-male social interactions in Drosophila

Division of Biology, California Institute of Technology, Pasadena, California, USA.
Nature Neuroscience (Impact Factor: 16.1). 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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    • " as CheB proteins ( Xu et al . , 2002 ; Park et al . , 2006 ) , ppk23 , ppk25 and ppk29 DEG / Na channels ( Lu et al . , 2012 ; Pikielny , 2012 ; Thistle et al . , 2012 ; Toda et al . , 2012 ; Vijayan et al . , 2014 ) , gustatory receptors like Gr39a , Gr32a and Gr68a ( Miyamoto and Amrein , 2008 ; Moon et al . , 2009 ; Koganezawa et al . , 2010 ; Wang et al . , 2011 ; Watanabe et al . , 2011 ) , and ionotropic receptors ( Koh et al . , 2014 ) . However , very few studies have considered the wiring of these pheromone - sensitive cells , even though male - to - male detection is affected when ' ' bitter ' ' gustatory receptors such as Gr32a and Gr38a are inactivated ( Miyamoto and Amrein , 2008 ; Moo"
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    • "D. melanogaster males lacking the gene encoding the Gr32a receptor court females from other species (Fan et al., 2013), court males from their own species (Miyamoto and Amrein, 2008) and have reduced aggression toward conspecific males (Wang et al., 2011; Andrews et al., 2014). Gr32a − mutant males are insensitive to 7-T indicating that Gr32a is a receptor for that pheromone (Wang et al., 2011). Although it probably has a mechanosensory component, one function of tapping during courtship appears to be connected to the chemosensory sensing of CH of conspecific and is in part connected to sex and species recognition (Kohatsu et al., 2011; Fan et al., 2013). "
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    • "As is mentioned briefly above, the power of cVA on its behavioral control differs depending on its olfactory context . For example, in addition to cVA, the presence of 7-tricosene, a cuticular component enriched in males, is essential to promote the full level of male–male aggression (Wang et al. 2011). Independently, Grillet et al. (2006) proposed the involvement of 7-tricosene in female mate choice. "
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