Identification of candidate chemosensory genes by transcriptome analysis in Loxostege sticticalis Linnaeus

Abstract

Loxostege sticticalis Linnaeus is an economically important agricultural pest, and the larvae cause great damage to crops, especially in Northern China. However, effective and environmentally friendly chemical methods for controlling this pest have not been discovered to date. In the present study, we performed HiSeq2500 sequencing of transcriptomes of the male and female adult antennae, adult legs and third instar larvae, and we identified 54 candidate odorant receptors (ORs), including 1 odorant receptor coreceptor (Orco) and 5 pheromone receptors (PRs), 18 ionotropic receptors (IRs), 13 gustatory receptors (GRs), 34 odorant binding proteins (OBPs), including 1 general odorant binding protein (GOBP1) and 3 pheromone binding proteins (PBPs), 10 chemosensory proteins (CSPs) and 2 sensory neuron membrane proteins (SNMPs). The results of RNA-Seq and RT-qPCR analyses showed the expression levels of most genes in the antennae were higher than that in the legs and larvae. Furthermore, PR4, OR1-4, 7–11, 13–15, 23, 29–32, 34, 41, 43, 47/IR7d.2/GR5b, 45, 7/PBP2-3, GOBP1, OBP3, 8 showed female antennae-biased expression, while PR1/OBP2, 7/IR75d/CSP2 showed male antennae-biased expression. However, IR1, 7d.3, 68a/OBP11, 20–22, 28/CSP9 had larvae enriched expression, and OBP15, 17, 25, 29/CSP5 were mainly expressed in the legs. The results shown above indicated that these genes might play a key role in foraging, seeking mates and host recognition in the L. sticticalis. Our findings will provide the basic knowledge for further studies on the molecular mechanisms of the olfactory system of L. sticticalis and potential novel targets for pest control strategies.

Identification of chemosensory genes from the antennal transcriptome of Indian meal moth Plodia interpunctella

“…CSPs represent a newly-discovered class of soluble carrier proteins with similar functions to OBPs in insect chemoreception [ 47 ]. CSPs have been found in insect chemosensory tissues and non-chemosensory organs, such as antennae [ 11 ], legs [ 48 ], labial palps [ 49 ], tarsi [ 50 ], brain [ 51 ], proboscis [ 52 ], pheromone gland [ 53 – 54 ] and wings [ 55 ]. We identified 15 putative CSP encoding transcripts, and found that six PintCSP genes were significantly expressed in the female antennae.…”

Antennal transcriptome analysis and expression profiles of olfactory genes in Anoplophora chinensis

“…A total of 44 OR genes were identified in the A. chinensis antennal transcriptomes, which is similar to the 43 genes in I. typographus , fewer than the 49 in D. ponderosae 34 and the 57 in M. caryae 33 , and considerably fewer than the 110 in T. castaneum 50 , but more than the 37 in A. glabripennis 10 and the 20 in Tenebrio molitor 17 . In a phylogenetic analysis, AchiOR35 clustered with Orco genes 51 , particularly those encoding Orco orthologues in T. castaneum . Achi OR35 could be the Orco in A. chinensis .…”

Identification of odorant-binding proteins in the reproductive system of Athetis dissimilis using transcriptome analysis

“…Insect OBPs are expressed in the sensory organs [22,25,37,[43][44][45]. 22,25,43,49−51 Our result showed that 23 AdisOBPs were significantly expressed in both female and male antennae compared to other tissues.…”