Molluscicidal Activity and Mechanisms of Triptolide against Pomacea canaliculata

Triptolide (TP) is a plant-derived diterpene lactone with broad-spectrum bioactivity. We indicated that TP exhibited strong molluscicidal activity against Pomacea canaliculata (72 h of LC₅₀ = 0.0921 mg/L). Histology revealed damage in the hepatopancreas, gills, kidney, testis, and albumen gland, particularly gill-cilia loss and testicular disorganization. The activities of aspartate transaminase (AST)/glutamic oxaloacetic transaminase (GOT), glutathione s-transferase (GST), and acetylcholinesterase (AChE) were significantly dysregulated. Proteomic analysis identified 225 differentially expressed proteins (DEPs) (111 downregulated), and 8 candidates were selected through functional annotation and docking. Combined with tissue observations, we focused on β-Tubulin (tubulin β-4B chain-like) and RNF34 (E3 ubiquitin-protein ligase RNF34-like). qRT-PCR confirmed that β-Tubulin siRNA-691 and RNF34 siRNA-368 reduced expression by 76.43 and 64.39%. β-Tubulin RNAi alleviated gill injury and increased 72 h survival to 73%. RNF34 RNAi did not improve survival, but its interaction with TP may reduce fecundity and population stability. These results reveal novel mechanisms of TP and suggest its potential as a molluscicide.