CRISPR/Cas9-mediated vitellogenin receptor knockout impairs vitellogenin uptake and reproduction in Bactrocera dorsalis.

BACKGROUND

Reproduction is a critical process in the insect life cycle, with the ovary serving as the central organ responsible for population maintenance. Successful development of the ovary is dependent on vitellogenin (Vg) transport into oocytes via the vitellogenin receptor (VgR). Exploring the VgR function is crucial for understanding the physiological mechanisms of insect ovarian development. However, the functional role of VgR in Bactrocera dorsalis (Hendel), a notorious agricultural invasive pest with exceptional reproductive plasticity, remains unclear.

RESULTS

Here, we identified BdVgR, an ovary-specific receptor with 1903 amino acids, as a critical determinant of reproductive success. CRISPR/Cas9-mediated BdVgR knockout resulted in a 211-bp genomic deletion spanning exonic (126 bp) and intronic (85 bp) regions, leading to near-complete loss of VgR expression in female adults. Functional analyses revealed that BdVgR deficiency disrupted ovarian Vg (Vg1/Vg2/Vg3) accumulation, impaired ovary maturation, and thus caused severe reproductive defects, including a decrease in the size of the ovaries by 49%, mating rates by 45%, egg production by 38%, and hatching rate by 22%.

CONCLUSION

Collectively, these findings indicate that BdVgR plays a key role in the reproductive process in B. dorsalis, and that disrupting VgR function can inhibit egg production, leading to sterility, which highlights the potential that targeting VgR via CRISPR can create genetically sterile females. Data are discussed with regard to integration of a sterile insect technique approach in the design of novel, efficient and safe pest management tactics. © 2025 Society of Chemical Industry.