Original Research ARTICLE
Glutathione-S-transferases in the olfactory organ of the noctuid moth Spodoptera littoralis, diversity and conservation of chemosensory clades
- 1Institue of ecology and environmental sciences - Paris, Sorbonne Universités, France
Glutathione-S-transferases (GSTs) are conjugating enzymes involved in the detoxification of a wide range of xenobiotic compounds. The expression of GSTs as well as their activities have been also highlighted in the olfactory organs of several species, including insects, where they could play a role in the signal termination and in odorant clearance. Using a transcriptomic approach, we identified 33 putative GSTs expressed in the antennae of the cotton leafworm Spodoptera littoralis. We established their expression patterns and revealed four olfactory-enriched genes in adults. In order to investigate the evolution of antennal GST repertoires in moths, we re-annotated antennal transcripts corresponding to GSTs in two moth and on coleopteran species. We performed a large phylogenetic analysis that revealed an unsuspected structural - and potentially functional - diversity of GSTs within the olfactory organ of insects. This led us to identify a conserved clade containing most of the already identified antennal-specific and antennal-enriched GSTs from moths. In addition, for all the sequences from this clade, we were able to identify a signal peptide, which is an unusual structural feature for GSTs. Taken together, these data highlight the diversity and evolution of GSTs in the olfactory organ of a pest species and more generally in the olfactory system of moths, and also the conservation of putative extracellular members across multiple insect orders.
Keywords: GST (glutathione S transferase), Spodoptera littoralis, Olfaction, detoxification, odorant degrading enzyme
Received: 29 Jun 2018;
Accepted: 27 Aug 2018.
Edited by:Monique Gauthier, Université Toulouse III Paul Sabatier, France
Reviewed by:Shannon B. Olsson, National Centre for Biological Sciences, India
Liang Sun, Tea Research Institute (CAAS), China
Copyright: © 2018 Durand, Pottier, Siaussat, Bozzolan, Maïbèche and Chertemps. 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. Thomas Chertemps, Sorbonne Universités, Institue of ecology and environmental sciences - Paris, Paris, France, firstname.lastname@example.org