# Grik2b and Grik2c kainate receptors regulate oviposition in Bactrocera dorsalis

## TL;DR

This study shows that two kainate receptors, Grik2b and Grik2c, regulate oviposition behavior in the fruit pest Bactrocera dorsalis.

## Contribution

The study identifies a novel neural conduction mechanism involving KARs in insect oviposition and potential molecular targets for pest control.

## Key findings

- Grik2b and Grik2c kainate receptors influence oviposition preference and egg-laying quantity in Bactrocera dorsalis.
- Glutamate acts as the neurotransmitter for Grik2b and Grik2c, and their knockdown disrupts oviposition behavior.
- KAR inhibitors were identified as potential tools to control insect oviposition.

## Abstract

Oviposition holds crucial significance for insect reproduction. Nevertheless, the research on the neural conduction mechanism of oviposition is still rather limited in most agricultural pests. Here, we demonstrate that the conserved Kainate receptors (KARs) expressed in the glutamatergic neurons (GNs) and the ovipositor neuromuscular junctions (NMJs) regulate the oviposition behavior in Bactrocera dorsalis. We identified two KARs (Grik2b and Grik2c), which control the oviposition behavior by influencing both oviposition preference and egg-laying quantity. Protein-ligand interaction indicated that glutamate serves as the neurotransmitter of Grik2b and Grik2c. Knockdown glutamate-coding genes adversely impacted oviposition preference and egg-laying quantity. Specific knockdown Grik2b (or Grik2c) in the GNs and NMJs could respectively influence oviposition preference and egg-laying quantity. Finally, inhibitors of KARs were screened for their ability to inhibit oviposition. Our study provides strong supporting evidence that a novel neural conduction mechanism for oviposition by uncovering the diverse roles of KARs and provides potential molecular target controlling insect oviposition.

Oviposition is crucial for insect fitness and represents a target for pest control. This study elucidates the role of two kainate receptors in regulating oviposition preference and egg-laying quantity in the fruit pest, Bactrocera dorsalis, and identifies relevant inhibitors of these receptors.