Original paper
Sublethal concentration of lambda-cyhalothrin inhibits the synthesis of juvenile hormone by stimulating allatostatins and leads to reproductive toxicity in Chrysoperla sinica
Wang, Nian-Meng; Gong, Si-Yuan; Wang, Zi-Jian; Xue, Yong-Rui; Zhang, Ya-Shu; Xue, Chao-Bin
Entomologia Generalis Volume 45 Number 3 (2025), p. 847 - 856
published: Aug 19, 2025
published online: Jul 14, 2025
manuscript accepted: Apr 24, 2025
final revised version received: Mar 15, 2025
manuscript revision requested: Mar 6, 2025
manuscript received: Nov 25, 2024
Open Access (paper may be downloaded free of charge)
Abstract
Allatostatins (Asts) represent a crucial class of insect neuropeptides that regulate juvenile hormone (JH) biosynthesis through rapid and reversible inhibition of JH synthesis and release in the corpora allata (CA). We have demonstrated that lambda-cyhalothrin (λCy) could induce severe reproductive toxicity by disrupting the hormone-vitellogenin signaling pathway in the lacewing, Chrysoperla sinica. Building on this foundation, the present study revealed that λCy exposure at sublethal concentrations triggers overexpression of the C-type allatostatin (AstC) encoding gene CsAstC, resulting in elevated AstC levels within the CA of C. sinica. Interference with CsAstC upregulated expression of the vitellogenin (Vg)-encoding gene CsVg, thereby stimulating vitellogenesis and ovarian development while rescuing the λCy-induced reproductive impairment. Further investigation demonstrated that targeted suppression of both CsAstC and its receptor gene CsAstCR increased JH titers while upregulating transcriptional levels of JH receptor methoprene-tolerant (Met) and its downstream transcription factor Krüppel homolog 1 (Kr-h1), encoded by CsMet and CsKr-h1 respectively. AstC is an upstream regulator of JH signaling pathway-mediated reproductive control in C. sinica. We showed that AstC acts on ATP-citrate lyase to inhibit the production of Acetyl-CoA in the CA cells of C. sinica, thereby affecting the synthesis of juvenile hormone. In conclusion, sublethal concentrations of λCy upregulated CsAstC expression to stimulate excessive production of AstC in the CA, resulting in hindered synthesis of JH, which was the essential reason attributing to reduced fecundity in C. sinica.
Keywords
pyrethroid • lacewing • hormone regulation • insect reproduction • ovarian development