# Prokaryotic Expression and Binding Characteristics of Odor-Binding Protein GqinOBP10 in Gynaephora qinghaiensis

## TL;DR

This study explores how a specific protein in a grassland pest helps it detect plant odors, which could lead to better pest control methods.

## Contribution

The study identifies GqinOBP10's strong binding to volatile plant compounds and its role in olfactory perception in G. qinghaiensis.

## Key findings

- GqinOBP10 shows strong binding to eight volatile plant compounds, especially 2-Amino-1-phenylethanol and 2-Oleoylglycerol.
- Silencing GqinOBP10 reduces its expression and impairs antennal responses to host plant volatiles in G. qinghaiensis.
- Molecular docking reveals hydrogen bonding and negative binding energy between GqinOBP10 and odorant molecules.

## Abstract

Gynaephora qinghaiensis is a major grassland pest common in the alpine meadows of the western plateau of China, and its biological behavior is affected by the synergy of a variety of chemicals in the environment. OBPs can dissolve and transport odor molecules such as volatile plant compounds through lymphatic fluid, which plays an important olfactory-to-olfactory role. However, the specific function of OBPs in the interaction mechanism between moths and volatile plant compounds is still unknown. The purpose of this study was to analyze the binding characteristics of GqinOBP10 and its volatile plant compounds in moths and to explore its role in the olfactory perception mechanism of moths so as to study the corresponding target ligands and achieve green control. The purified GqinOBP10 was subjected to fluorescence competitive binding to eight ligands. The 3D modeling of GqinOBP10 was carried out by the SWISS-MODEL website, and the molecular docking was carried out by Autodock 4.2.6 software, and the binding of GqinOBP10 to eight ligands was simulated and verified. The results showed that the cloned strain with the full length of GqinOBP10 was cloned. The fluorescence competition binding results showed that GqinOBP10 had strong binding ability to eight volatile plant compounds, among which the binding ability to 2-Amino-1-phenylethanol and 2-Oleoylglycerol was the strongest, and had high binding ability with the other six ligands. The molecular docking results showed that the binding energy of GqinOBP10 and eight odorant molecules was negative, and all of them could form 1~4 hydrogen bond for binding, among which the binding performance with 2-Oleoylglycerol was the best. The findings suggest that dsOBP10 injection leads to a notable decrease in both the expression levels of GqinOBP10 and the antennal potential response in male and female tissues. This indicates that GqinOBP10 is likely crucial for the localization and recognition of host plants in G. qinghaiensis. By silencing GqinOBP10, the olfactory perception of host volatiles is significantly impaired, highlighting the protein’s importance in the caterpillars’ ability to detect and respond to their environment. These insights provide a valuable basis for developing targeted attractants, potentially enhancing pest management strategies by manipulating olfactory cues in these caterpillars. Further research could explore the specific mechanisms by which GqinOBP10 influences olfactory perception and host plant selection.