A novel GSTe2 involved in metamorphosis by regulating 20E signal pathway in Tribolium castaneum

Abstract

Insect‐specific epsilon glutathion S‐transferases (GSTs) are a class of multifunctional GST superfamily, which play important roles in detoxification of xenobiotic substances. Most research on GSTs has focused on insecticide detoxification and resistance, with little research on other physiological functions. Here, we identified and cloned the novel GSTe2 from Tribolium castaneum (TcGSTe2). Recombinant TcGSTe2 protein was successfully overexpressed in Escherichia coli and purified with affinity purification, which had high ability to catalyze the conjugation of reduced glutathione with 1‐chloro‐2,4‐dinitrobenzene (CDNB). The expression level of TcGSTe2 was significantly decreased after exposure with four insecticides, phoxim, λ‐cyhalothrin, dichlorvos, and carbofuran, in larval stage. Interestingly, RNA interference knockdown of TcGSTe2 caused metamorphosis deficiency in larval and pupal stages by inhibiting the 20E signal pathway. Furthermore, exogenous 20E injection partially rescued this metamorphosis deficiency and also increased the expression levels of 20E downstream response genes. This study illustrated TcGSTe2 plays an important role at metamorphosis beside the insecticide detoxification and resistance in T. castaneum.

The glutathione biosynthesis is involved in metamorphosis, antioxidant function, and insecticide resistance in Tribolium castaneum

“…Moreover, TcGclc knockdown showed metamorphosis deficiency, downregulation of 20E‐related genes and partial rescue of the deficiency phenotype by exogenous 20E injection (Figs 3 and 4), which suggested that TcGclc knockdown led to metamorphosis deficiency by inhibition of 20E signal pathways. Previous studies have shown that GSH‐based GSTs were involved in metamorphosis by upregulating the 20E signal pathway in T. castaneum , 18 D. melanogaster , 32 Bombyx mori 33 and Aedes aegypti 34 ; in particular, the insect ecdysteroidogenic GST Noppera‐bo, which is the only known GST essential for ecdysone production in dipterans and lepidopterans 32,33 . Moreover, the Gclc null mutant in Drosophila indicated that Gclc‐mediated GSH biosynthesis is coupled to Noppera‐bo‐dependent ecdysone biosynthesis 16 .…”

“…32,33 Moreover, the Gclc null mutant in Drosophila indicated that Gclc-mediated GSH biosynthesis is coupled to Noppera-bo-dependent ecdysone biosynthesis. 16 In coleopteran insects such as T. castaneum, Nopperabo is not conserved 32 ; however, some GSTs also are involved in metamorphosis, 17,18 implying that Gclc-mediated GSH biosynthesis may be coupled to another type of GST for ecdysone biosynthesis. In terms of this, the current results suggest that TcGclc may participate in metamorphosis by providing GSH for GSTs that are involved in 20E signal pathway.…”

“…Moreover, Gclc mutation in D. melanogaster inhibited the 20‐hydroxyecdysone (20E) signal pathway, resulting in developmental arrest in the second‐instar larval stage and an inability to pupate 16 . Previous studies also demonstrated that some T.castaneum glutathione S‐transferases (TcGSTs; TcGSTd1, TcGSTe2) requiring GSH as a substrate participate in metamorphosis by regulating the 20E signal pathway in Tribolium castaneum , 17,18 suggesting the possibility that GSH could be involved in metamorphosis.…”

Novel Inhibitor of Glutamate-Cysteine Ligase Catalytic Subunit against Tribolium castaneum: High-Throughout Virtual Screening, Molecular Docking and Dynamics Simulation, and Bioassay

“…The main strategy for pest control is the use of synthetic insecticides, however, which develop rapid insecticide resistance, resulting in increased use of insecticides, negative health risks, and environmental pollution. , A family of phase II detoxification enzymes, glutathione S -transferases (GSTs) play a crucial role in the cellular detoxification of xenobiotics . Previous studies revealed that some TcGSTs (TcGSTd1–3, TcGSTs6, TcGSTe2) required GSH for development and detoxification in T. castaneum, suggesting the possibility that GSH biosynthesis could be a potential target for pest control.…”