Identification and functional verification of the target protein of pedunsaponin A in the gills of Pomacea canaliculata.

Background: Based on previous research indicating that pedunsaponin A (PA) can destroy the gills of Pomacea canaliculata, we chose the gill as the main research object, and identified the target protein of PA in the gills of P. canaliculata through proteomics and RNA interference (RNAi).

Results: Proteomics showed that 180 proteins were downregulated after PA treatment in P. canaliculata. Among them, we chose advillin (PcAdv), receptor type tyrosine protein phosphatase (PcRT) and unconventional myosin heavy chain 6 (PcUM) as candidate target proteins through bioinformatics analysis. The small interfering RNA (siRNA) with the best interference effect was identified through further screening. Gene interference rates were 97%, 98% and 82% for PcAdv, PcRT and PcUM, respectively. The results showed that after RNAi treatment, the mortality of P. canaliculata treated with PcAdv (60.0%) was significantly lower than that for the control (93.3%); histological analysis showed that the structure of the gill was intact, cilia shedding was reduced, and the survival rate of hemocytes had increased.

Conclusion: These findings indicate that, when the protein was absent or suppressed, the channel for entry of PA into the hemocytes of P. canaliculata was blocked, which reduced PA binding to hemocytes, and that there is a close relationship between shedding of gill cilia and PA entry into hemocytes. PcAdv is thus the key protein in PA destruction of gill cilia. Locating the proteins in gills that interact with drugs and investigating their mode of action is of great importance in the development of new molluscicides to control P. canaliculata populations.