Olfactory Reception of Host Alarm Pheromone Component by the Odorant-Binding Proteins in the Samurai Wasp, Trissolcus japonicus (Hymenoptera: Scelionidae)

• Published in: Frontiers in physiology 2020-09, Vol.11, p.1058-1058
• Main Authors: Zhang, Jinping, Zhong, Yongzhi, Tang, Rui, Rebijith, K. B., Li, Fengqi, Chen, Guohua, Zhang, Feng
• Format: Article
• Language: English
• Subjects: (E)-2-decenal; brown marmorated stink bug; egg parasitoid; insect olfaction; Physiology; transcriptome
• ISSN: 1664-042X; 1664-042X
• DOI: 10.3389/fphys.2020.01058

The samurai wasp, Trissolcus japonicus , is the predominant egg parasitoid of the brown marmorated stink bug, Halyomorpha halys , in its native range in China. ( E )-2-Decenal is a major component of the alarm pheromone of H. halys , an important invasive insect pest with significant economic importance. T . japonicus can be strongly repelled by ( E )-2-decenal, and thus its host location efficiency would be reduced in the field. Better understanding on the molecular basis of olfactory reception of this host alarm pheromone component by T. japonicus may provide opportunities to develop novel approaches to enhance biological control efficacy of the parasitoid against H. halys . We identified six Odorant Binding Proteins (OBPs) from T. japonicus by transcriptome sequencing, within which three classical OBPs were expressed in a heterologous expression system with E. coli , harvested, and then challenged with ( E )-2-decenal in binding assay experiments. Tjap OBP2 showed the highest binding ability to ( E )-2-decenal, compared to Tjap OBP1 and Tjap OBP3. Our results unambiguously suggest that Tjap OBP2 would play an important role in discriminating ( E )-2-decenal and could be a possible target for further intervention in the parasitoid–host system.