Integrated Time-Series Biochemical, Transcriptomic and Metabolomic Analyses Reveal Key Pathways and Concentration-Dependent Transitions in Chironomid Larvae (Propsilocerus akamusi) Under Chlorantraniliprole Stress

Abstract

Simple Summary Chironomids are among the most abundant and diverse freshwater insects, and are valued as pollution indicators and as key components of aquatic food webs. The widespread use of pesticides in agriculture has raised serious concerns about their effects on these aquatic organisms. To address this, we studied how a common insecticide, chlorantraniliprole (CAP), at environmentally relevant concentrations, affected chironomid larvae. Our findings showed that low doses of CAP triggered protective mechanisms in the larvae, such as detoxification and protein repair systems, to cope with stress. However, higher doses overwhelmed these defenses, disrupting energy production and causing severe cellular stress that ultimately led to death. We identified a key protein, PaHsp70, that was essential for larval survival under insecticide exposure. When its expression was significantly reduced, the larvae became more vulnerable. These findings reveal the adaptive strategies of chironomids to cope with pesticide stress from the environment, and highlight the urgent need to protect these animals and their freshwater habitats from agricultural pollution.