ZcGSTe1 regulates oxidative stress during vitellogenesis in Zeugodacus cucurbitae.

Chuan-Lian Liu; Meng Ma; Jun-Chen Yi; Dong Chen; Yun Wang; Jin-Jun Wang; Dong Wei

The melon fly, Zeugodacus cucurbitae Coquillett, is a significant quarantine pest belonging to the Diptera, known for its extended oviposition period, which causes significant economic damage to fruits and vegetables. Glutathione S-transferases (GSTs) are essential enzymes involved in insect pesticide detoxification and antioxidant enzyme activities. In this study, the GSTe1 gene was identified as being specifically expressed in the ovaries of melon fly. Heterologous expression demonstrated that the ZcGSTe1 recombinant protein catalyzed substrates 1-choro-2, 4-dinitrobenzene (CDNB) and peroxidase, with specific activities of 113.09 U/mg protein and 45.87 U/mg protein, respectively. The result of fluorescence in situ hybridization (FISH) analysis revealed that ZcGSTe1 was mainly enriched in oocytes. Using CRISPR/Cas9-mediated genome editing, a ZcGSTe1 knockout strain with a 28 bp deletion was created. Compared to wild-type females, homozygous mutants showed a 21% reduction in mating rate at 60 min, a 32% decrease in egg-laying over five days, and a 15.65% reduction in ovarian size of six-day-old females. Additionally, oocytes from five-day-old mutant females showed increased reactive oxygen species (ROS) levels. These findings suggest that ZcGSTe1 may play a role in ovarian development by regulating ROS levels through its antioxidant activity.

FRUIT flies; FLUORESCENCE in situ hybridization; RECOMBINANT proteins; REACTIVE oxygen species; GENOME editing

Entomologia Generalis, 2024, Vol 44, Issue 6, p1547

0171-8177

Academic Journal

10.1127/entomologia/2024/2816