Centre des Sciences du Goût et de l'Alimentation, Unité Mixte de Recherche-6265 Centre National de la Recherche Scientifique, Unité Mixte de Recherche-1324 Institut National de la Recherche Agronomique, Université de Bourgogne, Dijon, France.
PLoS One. 2011;6(5):e19770. doi: 10.1371/journal.pone.0019770. Epub 2011 May 20.
Pheromonal communication is crucial with regard to mate choice in many animals including insects. Drosophila melanogaster flies produce a pheromonal bouquet with many cuticular hydrocarbons some of which diverge between the sexes and differently affect male courtship behavior. Cuticular pheromones have a relatively high weight and are thought to be -- mostly but not only -- detected by gustatory contact. However, the response of the peripheral and central gustatory systems to these substances remains poorly explored. We measured the effect induced by pheromonal cuticular mixtures on (i) the electrophysiological response of peripheral gustatory receptor neurons, (ii) the calcium variation in brain centers receiving these gustatory inputs and (iii) the behavioral reaction induced in control males and in mutant desat1 males, which show abnormal pheromone production and perception. While male and female pheromones induced inhibitory-like effects on taste receptor neurons, the contact of male pheromones on male fore-tarsi elicits a long-lasting response of higher intensity in the dedicated gustatory brain center. We found that the behavior of control males was more strongly inhibited by male pheromones than by female pheromones, but this difference disappeared in anosmic males. Mutant desat1 males showed an increased sensitivity of their peripheral gustatory neurons to contact pheromones and a behavioral incapacity to discriminate sex pheromones. Together our data indicate that cuticular hydrocarbons induce long-lasting inhibitory effects on the relevant taste pathway which may interact with the olfactory pathway to modulate pheromonal perception.
信息素通讯对于许多动物（包括昆虫）的配偶选择至关重要。黑腹果蝇会产生一种带有许多表皮碳氢化合物的信息素气味，其中一些在性别之间存在差异，并以不同的方式影响雄性求偶行为。表皮信息素的相对分子质量较高，被认为主要（但不仅限于）通过味觉接触来检测。然而，这些物质对外周和中枢味觉系统的反应仍然知之甚少。我们测量了信息素表皮混合物对（i）外周味觉受体神经元的电生理反应、（ii）接收这些味觉输入的脑中枢的钙变化、（iii）控制雄性和 desat1 突变雄性引起的行为反应的影响，desat1 突变雄性表现出异常的信息素产生和感知。虽然雄性和雌性信息素对味觉受体神经元产生抑制样效应，但雄性信息素接触雄性前跗节会在专门的味觉脑中枢引起持续时间更长、强度更高的反应。我们发现，控制雄性的行为受到雄性信息素的抑制比受到雌性信息素的抑制更强，但在无嗅觉的雄性中，这种差异消失了。desat1 突变雄性对接触信息素的外周味觉神经元的敏感性增加，并且无法区分性信息素。我们的数据表明，表皮碳氢化合物会对相关味觉通路产生持久的抑制作用，这种作用可能与嗅觉通路相互作用，从而调节信息素感知。
