RT Journal Article SR Electronic T1 Gustatory Sensing Mechanism Coding for Multiple Oviposition Stimulants in the Swallowtail Butterfly, Papilio Xuthus JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 914 OP 924 DO 10.1523/JNEUROSCI.1405-12.2013 VO 33 IS 3 A1 Ryuda, Masasuke A1 Calas-List, Delphine A1 Yamada, Ayumi A1 Marion-Poll, Frédéric A1 Yoshikawa, Hiroshi A1 Tanimura, Teiichi A1 Ozaki, Katsuhisa YR 2013 UL http://www.jneurosci.org/content/33/3/914.abstract AB The swallowtail butterfly, Papilio xuthus, selectively uses a limited number of plants in the Rutaceae family. The butterfly detects oviposition stimulants in leaves through foreleg chemosensilla and requires a specific combination of multiple oviposition stimulants to lay eggs on the leaf of its host plants. In this study, we sought to elucidate the mechanism underlying the regulation of oviposition behavior by multiple oviposition stimulants. We classified chemosensilla on the tarsomere of the foreleg into three types (L1, L2, and S) according to their size and response to oviposition stimulants and general tastants. The L1 was more abundant in females than in males and responded preferentially to oviposition stimulants. Both L2 and S were common to both sexes and responded to general tastants. We found that five oviposition stimulants (synephrine, stachydrine, 5-hydroxy-Nω-methyltryptamine, narirutin, and chiro-inositol) elicited spikes from three specific gustatory receptor neurons (GRNs) within L1 sensilla. These three GRNs responded to a mixture of the five stimulants at concentrations equivalent to those found in the whole-leaf extract of citrus, and the mixture induced oviposition at levels comparable to whole-leaf extract. We propose that oviposition is triggered by the firing of three specific GRNs in L1 sensilla that encode the chemical signatures of multiple oviposition stimulants.