Identification of Odorant-Binding and Chemosensory Protein Genes in Adult Brains Using Transcriptome Analyses.

Large numbers of chemosensory genes have been identified in the peripheral sensory organs of the pest (Walker) to increase our understanding of chemoreception-related molecular mechanisms and to identify molecular targets for pest control. Chemosensory-related genes are expressed in various tissues, including non-sensory organs, and they play diverse roles. To better understand the functions of chemosensory-related genes in non-sensory organs, transcriptomic analyses of brains were performed. In total, 29 odorant-binding proteins (OBPs) and 16 chemosensory proteins (CSPs) putative genes were identified in the transcriptomic data set. The further examination of sex- and tissue-specific expression using RT-PCR suggested that eight (, , , , , , , and ) and eight (-, , -, and ) genes were expressed in the brain. Furthermore, bands representing most and could be detected in antennae, except for a few that underwent sex-biased expression in abdomens, legs, or wings. An RT-qPCR analysis of the expression profiles of six (, , , and ) and two ( and ) in different tissues and sexes indicated that was highly expressed in male brain, and and were female-biased and highly expressed in brain. The expression levels of and in brain were not significantly different between the sexes. The findings expand our current understanding of the expression patterns of s and s in sensory and non-sensory tissues. These results provide valuable reference data for exploring novel functions of OBPs and CSPs in and may help in developing effective biological control strategies for managing this pest by exploring novel molecular targets.