Characterization of the ligand-binding properties of odorant-binding protein 38 from Riptortus pedestris when interacting with soybean volatiles

• DOI: 10.3389/fphys.2024.1475489
• Publication Date: 2025-01-06T07:03:01Z
• Authors: Jianglong Guo; Panjing Liu; Xiaofang Zhang; Jingjie An; Yaofa Li; Tao Zhang; Zhanlin Gao
• Keywords: Physiology; fluorescence competitive binding; QP1-981; OBPs; molecular docking; soybean volatiles; Riptortus pedestris

Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) is a major soybean pest throughout East Asia that relies on its advanced olfactory system for the perception of plant-derived volatile compounds and aggregation pheromones conspecific host plant localization. Odorant binding proteins (OBPs) facilitate transport odorant across sensillum lymph within insect system, enabling their interaction with receptors (ORs). Real-time quantitative PCR (qRT-PCR) analyses, fluorescence-based competitive assays, molecular docking analyses were applied to assess expression ligand-binding properties OBP38 from R. peddestris. The qRT-PCR revealed high levels RpedOBP38 in antennae without any apparent sex bias, it was also highly expressed adult stage. Recombinant prepared by expressing E. coli BL21 (DE3) followed purification Ni-chelating affinity column. found bind most strongly trans-2-decenal (Ki = 7.440) trans-2-nonenal 10.973), β-pinene, (+) -4-terpineol, carvacrol, methyl salicylate, (-)-carvone. 3D structure contains six α-helices three interlocked disulfide bridges comprising stable hydrophobic pocket. In final series several polar (e.g., His 94, Glu97) nonpolar Leu29, Ile59) residues be involved RpedOBP38-ligand binding. These data support role volatiles derived plants, providing important insight into mechanisms govern recognition pedestris, thereby informing development ecologically friendly approaches managing infestations.