miR-252a-5p targets OVOL to regulate ovary development and egg viability (hatchability) in Helicoverpa armigera.

Disruption of reproduction is an important pest control tactics for management of high-fecundity pests like Helicoverpa armigera (Hübner). In this study, we investigated the role of the testis-biased miR-252a-5p in regulating gonad development and reproduction. Through a combination of bioinformatics prediction, dual luciferase reporter assays, functional injections (agomir, antagomir, and siRNA), and phenotypic evaluations, we identified OVOL as a key target gene of miR-252a-5p. We found that miR-252a-5p negatively regulates OVOL expression. Injection of miR-252a-5p agomir or OVOL siRNA into newly emerged females delayed egg maturation and reduced hatching rates. In contrast, inhibiting miR-252a-5p or knocking down OVOL in larval stages did not affect testis development or fertility. These results demonstrate that miR-252a-5p specifically targets OVOL to modulate ovarian development and reproductive success in H. armigera. Both miR-252a-5p and OVOL represent promising targets for reproduction-based control of this and other lepidopteran pests.