Identification and tissue expression profile of genes from three chemoreceptor families in an urban pest, Periplaneta americana

Abstract

Periplaneta americana is a notorious urban pest prevalent in human habitats; very little is known about its chemosensory mechanism. Employing the advanced next-generation sequencing technique, in the present study, we conducted transcriptome sequencing and analysis of the antennae of the adult males and females as well as their mouthparts using an Illumina platform. This resulted in the discovery of a huge number of the members of all major known chemosensory receptor families in P. americana, including 96 odorant receptors (ORs), 53 ionotropic receptors (IRs), and 33 gustatory receptors (GRs). Tissue expression profiles showed most of them mainly expressed in antennae and phylogenetic analysis demonstrated the expansion in the clade distinguishing them from other functionally well-known Lepidoptera species. A high percentage of chemosensory receptor genes (ORs in particular) showing female antenna bias in mRNA expression was observed. Our results provide a basis for further investigations on how P. americana coordinates its chemosensory receptor genes in chemical communication with environments, and for development of novel pest management approaches.

Identification of odorant‐binding and chemosensory protein genes and the ligand affinity of two of the encoded proteins suggest a complex olfactory perception system in Periplaneta americana

“…To identify putative P. americana OBPs and CSPs, we first constructed a local B last algorithm‐based program using the OBPs and CSPs of another cockroach, Blattella germanica (Niu et al ., ), to query the three P. americana adult transcriptomes (female antennae, male antennae, and mouthparts of mixed sexes) (Chen et al ., ). We then verified the obtained sequences by searches against the Pfam database (http://pfam.xfam.org/) to identify the gene family.…”

“…The mRNA levels were quantified using actin (GenBank accession number: AY116670), Adenosine diphosphate‐ribosylation factor and 60S ribosomal protein L17 as the reference genes. These three genes have been identified as stable reference genes between different tissue samples (Chen et al ., ). The relative expression levels of the and CSP mRNAs were calculated according to the 2 –ΔΔCq [(Cycle of quantification/qualification (Cq)] method as expression level = 2 –[(ΔCq_target)–(ΔCq_ref)]–[(ΔCq_control)–(ΔCq_ref)] , where ΔCq_ref is the average value of the three reference genes in each sample.…”

Molecular characterization and evolution of a chemosensory receptor gene family in three notorious rice planthoppers, Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus, based on genome and transcriptome analyses

“…These are ‘antennal IRs,’ which are conserved in various insect species and originate from the OR family, and ‘divergent IRs,’ which may originate from ‘antennal IRs’ that participate in gustation . IR sequences have been identified in many insect species from different orders, such as Rhagoletis pomonella (Diptera), Colaphellus bowringi (Hemiptera), A. gambiae (Diptera), B. mori and Manduca sexta (Lepidoptera), Spodoptera littoralis (Lepidoptera), Periplaneta americana (Blattodea), Chilo suppressalis (Lepidoptera) and Aphis gossypii (Hemiptera) . IR functions, other than those found in D. melanogaster , are not clear.…”

Insecticidal Activity of Melaleuca alternifolia Essential Oil and RNA-Seq Analysis of Sitophilus zeamais Transcriptome in Response to Oil Fumigation

“…Determination of the activity of these enzymes in insects after insecticide applications has been widely performed to better understand the insecticidal mechanism of xenobiotic compounds [19]. On the other hand, transcriptional regulation of gene expression in insects has been found to play an important role in insect response to various stressors [20, 21]. However, up to now, there is no any report about a global gene expression profile of pest insects in response to plant essential oils.…”