Analysis of Chemosensory Genes in Full and Hungry Adults of (Pentatomidae) Through Antennal Transcriptome.

The predatory insect (Hemiptera: Pentatomidae) is widely distributed in China, where it is also used to control many agricultural and forest pests. The chemosensory genes expressed in its antennae play crucial roles in food-seeking and mating behaviors. To better understand the olfaction of antennae, we identified the genes related to food-seeking and mating. Sequencing of the antennal transcriptomes of full and hungry male and female revealed 38 odorant-binding proteins (OBPs), 1 chemosensory protein (CSP), 1 Niemann-Pick C2 protein (NPC2), 3 odorant receptors (ORs), 12 ionotropic receptors (IRs), 2 gustatory receptors (GRs), and 3 sensory neuron membrane proteins (SNMPs). These results were used to construct phylogenetic trees. A quantitative real-time PCR (qRT-PCR) analysis showed that the relative transcript levels of , , and were higher in female than in male antennae in both full and hungry insects, but that the expression of and was higher only in full females. Thus, the latter genes may encode proteins involved in oviposition selection behavior. ( and ), , and (, , , , and ) were highly expressed only in the antennae of full males, indicating the participation of these genes in mate-searching or male pheromone recognition. The expression of in the antennae of starved males, (, , and ) in the antennae of starved females, and (, , and ) in the antennae of starved males and females suggested that these genes encode food-seeking functions. Our identification of chemosensory genes in antennae and their differential expression in full and hungry insects provides the basis for further functional studies on the chemoreception system of and the sex hormones of predatory insects.