Original Research ARTICLE
Transcriptome Surveys in Silverfish Suggest a Multistep Origin of the Insect Odorant Receptor Gene Family
- 1The New Zealand Institute for Plant & Food Research Ltd, New Zealand
- 2Max Planck Institute for Chemical Ecology, Germany
- 3Czech University of Life Sciences Prague, Czechia
- 4School of Biological Sciences, Faculty of Science, University of Auckland, New Zealand
The insect odorant receptor (Or) gene family is among the largest multigene families in insect genomes, but its evolutionary origin and mode of expansion is still a matter of debate. We performed transcriptomic surveys of two wingless insect species, the silverfish Lepisma saccharina and Tricholepidion gertschi, and identified multiple Or gene family members in both species. A phylogenetic analysis suggests that the silverfish Ors do not fall into the clade comprised of more derived flying insect ligand-binding Ors, but, along with bristletail, firebrat and some mayfly Ors, are consistently resolved as a distinct set of genes that may constitute an evolutionary intermediate between gustatory receptors and the more derived Ors of flying insects. We propose to consider these “primitive Ors” separately from higher insect Ors until their cellular expression patterns and function are resolved and suggest a multistep evolutionary scenario ultimately leading to the highly sensitive, rapidly evolving and physiologically diverse Or gene family observed in higher insects.
Keywords: odorant receptor, gustatory receptor, chemosensation, Olfaction, Silverfish, evolution, Multigene Family, Zygentoma
Received: 28 May 2019;
Accepted: 09 Jul 2019.
Edited by:Emmanuelle Jacquin-Joly, Institut National de la Recherche Agronomique (INRA), France
Reviewed by:Wei Xu, Murdoch University, Australia
Camille Meslin, INRA Centre Versailles-Grignon, France
Copyright: © 2019 Thoma, Missbach, Jordan, Grosse-Wilde, Newcomb and Hansson. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Michael Thoma, The New Zealand Institute for Plant & Food Research Ltd, Auckland, New Zealand, email@example.com