Manduca sexta females attract their mates with the release of a species-specific sex-pheromone blend, with bombykal (E,Z)-10,12-hexadecadienal and (E,E,Z)-10,12,14-hexadecatrienal being the two major components. Here, we searched for the hawkmoth bombykal receptor in heterologous expression systems. The putative pheromone receptor MsexOr1 coexpressed with MsexOrco in Xenopus oocytes elicited dose-dependent inward currents upon bombykal application (10–300 μmol l−1), and coexpressed in HEK293 and CHO cells caused bombykal-dependent increases in the intracellular free Ca2+ concentration. In addition, the bombykal receptor of Bombyx mori BmOr3 coexpressed with MsexOrco responded to bombykal (30–100 μmol l−1) with inward currents. In contrast, MsexOr4 coexpressed with MsexOrco responded neither to bombykal (30–100 μmol l−1) nor to the (E,E,Z)-10,12,14-hexadecatrienal mimic. Thus, MsexOr1, but not MsexOrco and probably not MsexOr4, is the bombykal-binding pheromone receptor in the hawkmoth. Finally, we obtained evidence that phospholipase C and protein kinase C activity are involved in the hawkmoth's bombykal-receptor-mediated Ca2+ signals in HEK293 and CHO cells.
The authors declare no competing or financial interests.
S.M., N.F. and L.H. performed the experiments, D.W., M.S. and K.T. analyzed the data, D.W. and M.S. wrote the manuscript. All authors contributed to the design of the study and to the final version of the manuscript.
This work was supported by the Max-Planck-Gesellschaft, the Deutsche Forschungsgemeinschaft (grant SPP 1392 to D.W. and M.S.) and the Japan Science and Technology Agency ERATO Touhara Chemosensory Signal Project (grant JPMJER1202 to K.T.).
- Received December 12, 2016.
- Accepted February 23, 2017.
- © 2017. Published by The Company of Biologists Ltd