The miRNA-275 Targeting RpABCG23L is Involved in Pyrethroid Resistance in the Bird Cherry-Oat Aphid, a Serious Agricultural Pest

<i>Rhopalosiphum padi</i> is a global agricultural pest which had developed resistance to different insecticides. The ATP-binding cassette (ABC) transporter plays an important role in insecticide resistance. However, ABC transporters' role and regulatory mechanism in mediating <i>R. padi</i> 's response to pyrethroids are unclear. In this study, we found that <i>RpABCG23L</i> was significantly overexpressed in the pyrethroid-resistant strains of <i>R. padi</i>. Knockdown of <i>RpABCG23L</i> significantly increased the susceptibility of <i>R. padi</i> to lambda-cyhalothrin and bifenthrin. Luciferase reporter gene analysis showed that miR-275 binds to the <i>RpABCG23L</i> coding region and down-regulates its expression. Injection of miR-275 mimics significantly reduced <i>RpABCG23L</i> expression and increased <i>R. padi</i> susceptibility to lambda-cyhalothrin and bifenthrin, while miR-275 inhibitor injection enhanced <i>RpABCG23L</i> expression and increased tolerance to both insecticides. The results provide a theoretical basis for understanding the mechanism of miRNA-mediated pyrethroid resistance, and open up a new way for the development of miRNA-based biopesticides.