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

Zhao-Qun Li,Peng He,Yan Chen,Ya-Nan Zhang,Ming He

doi:10.1038/srep27495

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.

Highlights

GRs, the other members of the chemosensory superfamily, are likely to have the same ancestor as ORs and have a seven transmembrane structure[15]
We determined the repertoire of chemosensory receptor families (ORs, IRs, and GRs) in a notorious urban pest, P. americana
The number of ORs was much higher than in the two other Blattaria species, Z. nevadensis (60 ORs, genome data)[31] and B. germanica (5 ORs, antennal transcriptome data)[30]. It was higher than the 62 ORs found in D. melanogaster[15] and the 79 ORs in A. gambiae[6,35], but was much lower than the number of ORs reported in T. castaneum (259 ORs)[8], A. mellifera (170 ORs)[7], and L. moratoria (142 ORs)[36]

Summary

Introduction

GRs, the other members of the chemosensory superfamily, are likely to have the same ancestor as ORs and have a seven transmembrane structure[15]. In the present study, we sequenced and analyzed three transcriptomes of the adults of P. americana using next-generation sequencing, and identified 190 putative chemosensory receptor genes. These included 96 ORs, 61 iGluRs/IRs, and 33 GRs. These included 96 ORs, 61 iGluRs/IRs, and 33 GRs To understand their potential functions, we conducted gene ontology (GO) annotation and scanned the tissue-specific expression of these sequences, as well. We examined their phylogenetic relationships with some other insect species

Methods

Results

Conclusion