Transcriptomic traces of adaptive changes and detoxification in Glyptotendipes tokunagai (Chironomidae) exposed to cadmium-based sediments environment

Abstract

The chironomid Glyptotendipes tokunagai was chosen to study cadmium's ecotoxicity, owing to its prevalence in benthic sediments. Over 10 days, we exposed chironomids to three different concentrations of cadmium chloride (CdCl2) and examined their gene expression at maximal bioaccumulation levels. The results clearly showed 10275 significantly expressed genes with an average length of 795 bp. Ion homeostasis and Ca2+ ion transport were severely disrupted by Cadmium exposure, impairing the neurological system. Gene regulation indicated increased ROS due to cellular component process disruption, causing DNA damage, oxidative stress, and autophagy-mediated programmed cell death. Cadmium bioaccumulation hindered cuticle formation and growth, requiring more energy from the organism to resist the stress. An enriched detoxification route in response to the metabolic feedback mechanism was an aftereffect of energy deficiency related to their effective survival rate. The study has identified gene expression risk markers for signal transduction disruption, cellular development impairment, ATP synthesis-coupled energy deficit, and detoxification. These risk indicators must be closely monitored to ensure environmental safety.

Keywords

• Environmental pollution
• Cadmium stress
• Transcriptome
• Chironomids
• Detoxification