Identification and tissue distribution of chemosensory protein and odorant binding protein genes in Tropidothorax elegans Distant (Hemiptera: Lygaeidae)

Yue-Qin Song,Jun Du,Hui-Zhong Sun

doi:10.1038/s41598-018-26137-6

Abstract

Tropidothorax elegans Distant (Hemiptera: Lygaeidae) is an insect pest that inflicts damage to vegetables and flowering plants across China. The olfactory system regulates insect behavior, such as feeding, mating, oviposition and predator avoidance. Odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) are two groups of small soluble proteins that initiate olfactory signal transduction in insects. In this study, we generated antennal transcriptomes of male and female T. elegans, and identified 19 putative OBP (14 classic OBPs and five plus-C OBPs) and seven CSP genes. Through real-time quantitative PCR analysis, we found that 14 of the 19 OBP genes were highly expressed in the antennae of both adult females and males, and 3 OBP genes were expressed higher in the antennae of males than females. Some OBP genes were also highly expressed in the legs or wings. Three CSP genes were highly expressed in the antennae of both sexes, and TeleCSP7 showed higher expression in male antennae compare to females. Interestingly, one CSP gene, TeleCSP2, was expressed in all olfactory tissues. Our results provide molecular insights into further investigating of the olfactory system of an important plant pest, T. elegans.

Highlights

Tropidothorax elegans Distant (Hemiptera: Lygaeidae) is an insect pest that inflicts damage to vegetables and flowering plants across China
To conduct a phylogenetic analysis of Odorant-binding proteins (OBPs), we used a total of 160 OBP protein sequences from seven different Hemiptera insects, including the 19 predicted OBPs we identified from T. elegans, 30 OBPs from H. halys, 39 OBPs from A. lucorum, 14 OBPs from A. lineolatus, 39 OBPs from L. lineolaris, 15 OBPs from A. suturalis, and four OBPs from Chinavia ubica
The number of OBP genes we identified in T. elegans is lower than other spcies, such as 38 OBPs in A. lucorum[9, 33] OBPs in L. lineolaris[8] and 28 OBPs in N. ericae[24], but was similar to some Hemiptera species, such as 16 OBPs in A. suturalis[25] and 14 OBPs in A. lineolatus[26]

Summary

Introduction

Tropidothorax elegans Distant (Hemiptera: Lygaeidae) is an insect pest that inflicts damage to vegetables and flowering plants across China. Odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) are two groups of small soluble proteins that initiate olfactory signal transduction in insects. Three CSP genes were highly expressed in the antennae of both sexes, and TeleCSP7 showed higher expression in male antennae compare to females. OBPs are highly expressed in the antennae, and the primary function of OBPs are to transport odorant molecules to ORs in the antenna[8,9]. Recent studies have found expression of OBPs in nonsensory organs, such as pheromone glands and reproductive organs. This suggests that OBPs serve an additional function as chemical compound carrier, which may be analogous to the vertebrates urinary and salivary proteins as well as some insect chemosensory proteins[10,11]. MF593898 MF593899 MF593900 MF593901 MF593902 MF593903 MF593904 MF593905 MF593906 MF593907 MF593908 MF593909 MF593910 MF593911 MF593912 MF593913 MF593914 MF593915 MF593916 MF598723 MF598724 MF598725 MF598726 MF598727 MF598728 MF598729

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Conclusion