Binding Properties of Odorant-Binding Protein 4 of Tirathaba rufivena to Areca catechu Volatiles

Abstract

Odorant-binding proteins (OBPs) play a key role in the olfactory system and are essential for mating and oviposition host selection. Tirathaba rufivena, a serious lepidopterous insect pest of the palm area in recent years, has threatened cultivations of Areca catechu in Hainan. Female-biased odorant-binding protein 4 of T. rufivena (TrufOBP4) expression was hypothesized to participate in the process of oviposition host recognition and localization. In this study, we cloned and analyzed the cDNA sequence of TrufOBP4. The predicted mature protein TrufOBP4 is a small, soluble, secretory protein and belongs to a classic OBP subfamily. Fluorescence binding assay results showed that TrufOBP4 had high binding abilities with the host plant volatiles, octyl methoxycinnamate, dibutyl phthalate, myristic acid and palmitic acid. These four components tend to dock in the same binding pocket based on the molecular docking result. The interactions and contributions of key amino acid residues were also characterized. This research provides evidence that TrufOBP4 might participate in the chemoreception of volatile compounds from inflorescences of A. catechu and can contribute to the integrated management of T. rufivena.

Molecular Characterization of Plant Volatile Compound Interactions with Cnaphalocrocis medinalis Odorant-Binding Proteins

“…Insect olfactory systems allow for the recognition of trace volatiles from hosts or mates and the avoidance of toxic compounds or natural enemies [ 35 ]. OBPs are critical proteins that bind odor molecules during olfactory perception and transport odor molecules across the lymphatic environment [ 36 ].…”

Antennal Transcriptome Analysis of Olfactory Genes and Characterization of Odorant Binding Proteins in Odontothrips loti (Thysanoptera: Thripidae)

“…With the development of molecular dynamics, homologous modeling and molecular docking make up for this shortcoming. Based on protein 3D structure and molecular docking, a large number of potential semiochemicals were identified, for example, β-ionone to BtabOBP3 in Bemisia tabaci Gennadius [ 41 ], octyl methoxycinnamate, dibutylphthalate, myristic acid and palmitic acid to TrufOBP4 in Tirathaba rufivena Walker [ 40 ] and E10-16: Ald to CpinPBP2 in Conogethes pinicolalis Inoue and Yamanaka [ 70 ]. In our study, p -Menth-8-en-2-one was screened due to its strong binding ability to O. lot OBP6.…”

“…The assessment of the ligand binding properties of olfactory proteins, particularly OBPs or CSPs, is essential for understanding their physiological functions. Fluorescence competition assay provides an initial insight into protein binding properties by calculating the dissociation constants of fluorescent probes and protein complexes in competition with ligands and is widely used in studies of insect olfactory proteins [ 40 , 41 ]. With the development of molecular dynamics studies, such as homology modelling and molecular docking, it is possible to accurately predict the binding properties of olfactory proteins, making the detection of behaviorally active pest compounds more efficient [ 40 , 42 ].…”

Binding Properties of Odorant-Binding Protein 7 to Host Volatiles in Larvae of Spodoptera frugiperda

“…30 TrufOBP4 in Tirathaba rufivena had ligand-binding abilities to four host plant volatiles. 31 EoblOBP6 in Ectropis obliqua could bind to tea plant volatiles benzaldehyde. 32 Not only the fluorescence competitive binding assays in vitro but also RNA interference (RNAi) technology in vivo was used for functional identification of OBPs.…”

“…For example, DabiOBP17 in Dioryctria abietella had high binding affinity to floral volatile, benzyl benzoate . TrufOBP4 in Tirathaba rufivena had ligand-binding abilities to four host plant volatiles . EoblOBP6 in Ectropis obliqua could bind to tea plant volatiles benzaldehyde .…”