Identification and expression of chemosensory receptor genes in the egg parasitoid Trissolcus basalis

• Published in: Comparative biochemistry and physiology. Part D, Genomics & proteomics Genomics & proteomics, 2021-03, Vol.37, p.100758-100758, Article 100758
• Main Authors: Chen, Huayan, Lahey, Zachary, Talamas, Elijah J., Johnson, Norman F.
• Format: Article
• Language: English
• Subjects: Gustatory receptor; Host finding; Hymenoptera; Ionotropic receptor; Olfactory receptor
• ISSN: 1744-117X; 1878-0407
• DOI: 10.1016/j.cbd.2020.100758

Parasitic wasps largely rely on chemosenses to locate resources. Understanding the evolution of their chemoreceptors can help elucidate the mechanisms underlying host adaptation and speciation. Trissolcus basalis is a biological control agent of the southern green stink bug, a pantropical pest, and is ideal for investigating the evolution of chemoreceptors. We identified 34 gustatory receptors, 170 odorant receptors, one odorant co-receptor, and 23 ionotropic receptors. Comparison with other Hymenoptera revealed species-specific expansions of 21 Grs and 53 Ors. Most of these Or expansions have 9 exons. Gender- and tissue-specific analyses showed that 5 Grs and 54 Ors are expressed only in antennae in both sexes, 66 Ors in female antennae only, and 4 Ors in male antennae alone. The identification and expression profile of chemosensory receptor genes in T. basalis helps in understanding the link between the evolution of chemoreceptors and speciation in parasitic wasps. [Display omitted] •The chemoreceptors of the biocontrol agent Trissolcus basalis are characterized.•The genome encodes 34 gustatory, 170 odorant, and 23 ionotropic receptors.•21 gustatory receptors and 53 odorant receptors are unique to this species.•3 gustatory receptors are expressed only in males and 1 is only found in females.•38 olfactory receptors are expressed only in the antennae, 5 of which are unique to females.