Superfund Research Program
Proteome Response to Toxic Perturbation
The Proteomics Core has completed development of a workflow for label-free quantitation of proteins in complex mixtures. The proteomics core has applied this workflow with three other Superfund projects this year. First, it has been demonstrated that sub lethal effects of copper oxide nanoparticles on fish depend on environmental context (collaboration with Development of Rapid, Miniaturized Biosensors). This finding has important implications for regulators because it shows that limits of toxicity are not static but are greatly influenced by other environmental parameters and the overall environmental context in which toxins occur. Second, the proteomics core has derived novel fish cell lines that can now be used for high-throughput toxicity testing of aquatic environmental samples (Integrated Response to Toxic Perturbation). The label-free quantitative proteomics workflow developed was applied for comparing the proteomes of cell lines that were derived from different tissues. This analysis demonstrated the expression of many tissue-specific marker proteins in these cell lines. Therefore, proteomics has been shown to be a very effective tool for assessing the differentiation state and tissue origin of cell lines, which can now be monitored as passage number increases to maintain a good baseline and comparability for future toxicity testing employing these cell lines. Third, using quantitative label-free protemics core has identified naphthalene-derivative-adducted and glycosylated that are altered by naphthalene exposure of mice (Urinary Protein Biomarkers for Assessing the Potential Toxicity of Naphthalene in Humans). Differences in proteome responses to naphthalene inhalation have been revealed between nasal olfactory epithelium and lung airway epithelium. In particular, protein glycation was shown to markedly differ between the two tissues suggesting that naphthalene exposure causes non-enzymatic, covalent addition of carbohydrate moieties to proteins primarily in lung epithelium. Because protein glycation is often associated with cell/ tissue damage and an indicator of injury these data suggest that nasal olfactory epithelium is more resistant to naphthalene exposure than lung airway epithelium.