Identification of Chemosensory Genes Based on the Antennal Transcriptomic Analysis of Plagiodera versicolora

SIMPLE SUMMARY: In this study, we conducted a transcriptome analysis of adult antennae in Plagiodera versicolora (Coleoptera: Chrysomelidae) and identified a total of 98 candidate chemosensory genes, encoding 40 odorant receptors (ORs), 7 ionotropic receptors (IRs), 13 gustatory receptors (GRs), 10 chemosensory proteins (CSPs), 24 odorant binding proteins (OBPs), and 4 sensory neuron membrane proteins (SNMPs). The tissue expression profiles showed that almost all PverOBPs and PverORs were highly expressed in the antennae. In addition, the results revealed that PverOBP10, PverOBP12, PverOBP18, PverOR24, and PverOR35 showed female-biased expression profiles, indicating that these receptors may be involved in some female-specific behaviors such as oviposition site seeking. This work greatly promotes the understanding of the olfactory system and will help provide insight for functional studies of the chemoreception mechanism in P. versicolora. ABSTRACT: Insects can sense surrounding chemical signals by their accurate chemosensory systems. This system plays a vital role in the life history of insects. Several gene families participate in chemosensory processes, including odorant receptors (ORs), ionotropic receptors (IRs), gustatory receptors (GRs), chemosensory proteins (CSPs), odorant binding proteins (OBPs), and sensory neuron membrane proteins (SNMPs). Plagiodera versicolora (Coleoptera: Chrysomelidae), is a leaf-eating forest pest found in salicaceous trees worldwide. In this study, a transcriptome analysis of male and female adult antennae in P. versicolora individuals was conducted, which identified a total of 98 candidate chemosensory genes including 40 ORs, 7 IRs, 13 GRs, 10 CSPs, 24 OBPs, and 4 SNMPs. Subsequently, the tissue expression profiles of 15 P. versicolora OBPs (PverOBPs) and 39 ORs (PverORs) were conducted by quantitative real-time PCR. The data showed that almost all PverOBPs and PverORs were highly expressed in the male and female antennae. In addition, several OBPs and ORs (PverOBP10, PverOBP12, PverOBP18, PverOR24, and PverOR35) had higher expression levels in female antennae than those in the male antennae, indicating that these genes may be taking part in some female-specific behaviors, such as find mates, oviposition site, etc. This study deeply promotes further understanding of the chemosensory system and functional studies of the chemoreception genes in P. versicolora.