Sensory genes identification with head transcriptome of the migratory armyworm, Mythimna separata

Abstract

Sensory system plays important roles in a wide array of insect’s behavior and physiological events, including the host landing and locating, feeding, flying, sex responding, mating and oviposition which happen independently and in sequence. The armyworm Mythimna separata (Lepidoptera: Noctuidae) of migratory insect is destructive for alimentarn crop and economic crop throughout the world. Here we present the high throughput sequencing of the head transcriptome and identify members of the major sensory genes which are crucial for armyworm’s success worldwide, including 8 opsins, 22 chemosensory proteins, 50 odorant binding proteins, 60 odorant receptors, 8 gustatory receptors, 24 ionotropic receptors, and 2 sensory neuron membrane proteins. It is worth noting that a duplication of the LW opsin gene exists in this insect. Several genes were clustered with functionally validated genes, such as Co-receptors of OR and IR, PBPs, PRs, CO2 GRs, bitter GRs and sweet GRs, were also identified. The transcriptome gene library provided the basis for further studies that elucidate the fundamental molecular mechanism of biology and control in M. separata. Our research exhibits the first comprehensive catalogue of the sensory genes fundamental for success and distribution in M. separata, which are potential novel targets for pest control strategies.

Screening potential reference genes for quantitative real-time PCR analysis in the oriental armyworm, Mythimna separata

“…The M . separata genome has been sequenced, and transcriptomes for insect development, exposure to stressful conditions, and migratory behavior have been described for this species [ 21 – 24 ]. Numerous qRT-PCR studies have been conducted with M .…”

“…separata [ 22 ]. Furthermore, Chang et al [ 23 ] and Liu et al [ 24 ] identified numerous genes with putative roles in olfactory, sensory and taste transduction by transcriptional analysis of gene expression in the heads and antennae of M . separata .…”

Identification of candidate chemosensory genes in Mythimna separata by transcriptomic analysis

“…There are three previous studies antennal on transcriptome of M. separata. He et al (2017) identified 126 olfactory genes including 43 ORs, 13 GRs, 16 IR, 37 OBPs, 14 CSPs, and 3 SNMPs [ 58 ], Chang et al (2017) obtained 130 chemosensory genes encoding 71 ORs, 1 GR, 8 IRs, 32 OBPs, 16 CSPs, and 2 SNMPs [ 59 ] and Liu et al (2017) gained 60 ORs, 8 GRs, 24 IRs, 50 OBPs, 22 CSPs and 2 SNMPs [ 60 ]. Compared with Liu’s study which was also on the head transcriptome of M. separate , we identified some novel chemosensory genes and the lengths of the genes were significantly longer.…”

Nucleases as a barrier to gene silencing in the cotton boll weevil, Anthonomus grandis

“…Therefore, RNAi is an environmentally safe strategy that decreases off-target effects [ 19 ]. Transcriptome analysis can be performed to identify genes that are differentially expressed throughout the lifecycle processes of insects [ 71 ]. Using sequence information from the transcriptome, RNAi technology represents an advance in the genetic improvement of crops by conferring resistance to insect pests [ 72 ].…”