A cellular genetics approach identifies gene-drug interactions and pinpoints drug toxicity pathway nodes

Area of Science:

• Toxicology
• Genetics
• High-throughput screening

Background:

• Current toxicity testing relies on repurposed drug discovery assays.
• A need exists for integrated approaches combining in vitro screening with genetic methods.
• Identifying genes and pathways underlying chemical toxicity is crucial for risk assessment.

Purpose of the Study:

• To develop and demonstrate an integrated approach for identifying genes and pathways involved in chemical and drug toxicity.
• To leverage genetic variation across mouse strains to uncover mechanisms of differential toxicity.
• To validate candidate genes and pathways through experimental methods.

Main Methods:

• Primary embryonic fibroblasts from 32 mouse strains were treated with 65 diverse compounds.
• High-content imaging assessed cellular responses including cell loss, membrane permeability, mitochondrial function, and apoptosis at 24 and 72 hours.
• Genetic association analysis identified candidate loci linked to strain-specific toxicity responses.

Main Results:

• Genetic association analysis yielded candidate loci for variable strain responses to chemicals.
• The candidate gene Cybb, implicated in rotenone sensitivity, was experimentally validated in vitro and in vivo.
• Pathway analysis identified over-connected nodes as potential core regulators of toxicity pathways.

Conclusions:

• The integrated in vitro screening and genetic approach effectively identifies genes and pathways in chemical toxicity.
• This method provides a powerful tool for dissecting the genetic basis of differential chemical responses.
• The findings highlight potential core regulatory points for targeted toxicity pathway interventions.