Table_2_Identification of Olfactory Genes From the Greater Wax Moth by Antennal Transcriptome Analysis.XLSX

The olfactory system is used by insects to find hosts, mates, and oviposition sites. Insects have different types of olfactory proteins, including odorant-binding proteins (OBPs), chemosensory proteins (CSPs), odorant receptors (ORs), ionotropic receptors (IRs), and sensory neuron membrane proteins (SNMPs) to perceive chemical cues from the environment. The greater wax moth, Galleria mellonella, is an important lepidopteran pest of apiculture. However, the molecular mechanism underlying odorant perception in this species is unclear. In this study, we performed transcriptome sequencing of G. mellonella antennae to identify genes involved in olfaction. A total of 42,544 unigenes were obtained by assembling the transcriptome. Functional classification of these unigenes was determined by searching against the Gene Ontology (GO), eukaryotic orthologous groups (KOG), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. We identified a total of 102 olfactory-related genes: 21 OBPs, 18 CSPs, 43 ORs, 18 IRs, and 2 SNMPs. Results from BLASTX best hit and phylogenetic analyses showed that most of the genes had a close relationship with orthologs from other Lepidoptera species. A large number of OBPs and CSPs were tandemly arrayed in the genomic scaffolds and formed gene clusters. Reverse transcription-quantitative PCR results showed that GmelOBP19 and GmelOR47 are mainly expressed in male antennae. This work provides a transcriptome resource for olfactory genes in G. mellonella, and the findings pave the way for studying the function of these genes.

昆虫依靠嗅觉系统搜寻寄主、配偶与产卵位点。昆虫拥有多种嗅觉蛋白家族，包括气味结合蛋白（odorant-binding proteins, OBPs）、化学感受蛋白（chemosensory proteins, CSPs）、气味受体（odorant receptors, ORs）、离子型受体（ionotropic receptors, IRs）以及感觉神经元膜蛋白（sensory neuron membrane proteins, SNMPs），用于感知环境中的化学信号。大蜡螟（Galleria mellonella）是养蜂业中重要的鳞翅目害虫，但该物种气味感知的分子机制目前仍不明确。本研究对大蜡螟的触角进行转录组测序，以鉴定参与嗅觉过程的基因。最终通过转录组组装共获得42544条单基因（unigenes）。通过比对基因本体论（Gene Ontology, GO）、真核生物直系同源群（eukaryotic orthologous groups, KOG）以及京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）数据库，完成了这些单基因的功能注释分类。本研究共鉴定得到102个嗅觉相关基因：21个OBPs、18个CSPs、43个ORs、18个IRs以及2个SNMPs。BLASTX最佳匹配与系统发育分析结果显示，绝大多数基因与其他鳞翅目物种的同源基因具有较近的进化关系。大量OBPs与CSPs在基因组支架上呈串联排列，形成了基因簇。反转录定量PCR结果表明，GmelOBP19与GmelOR47主要在雄虫触角中表达。本研究为大蜡螟的嗅觉基因提供了转录组资源，研究结果为后续解析这些基因的功能奠定了基础。