Project description:Mycobacterium dioxanotrophicus PH-06 can degrade 1,4-dioxane (dioxane), which is a groundwater contaminant of emerging concern. In order to find the genes involved in dioxane degradation. RNA sequencing was first used to investigate gene expression levels of PH-06 during growth on two different carbon sources (dioxane and glucose). The sequencing shows that a monooxygenase gene cluster was upregulated when treated with dioxane relative to glucose.
Project description:We evaluated liver tissues of B6D2F1/Crl mice exposed to 0, 40, 200, 600, 2000, or 6000 ppm 1,4-dioxane in drinking water for 7, 28, or 90 days in support of an investigation of the mode of action for 1,4-dioxane-induced murine liver tumors. TempO-Seq technology was used to measure global hepatic gene expression. Exposure-induced transcriptional responses increased by dose and exposure duration, with few differentially expressed genes at 40 and 200 ppm regardless of exposure duration. Pathway enrichment analysis identified significant perturbations in pathways associated with xenobiotic metabolism, complement and coagulation cascades and fatty acid metabolism in 600, 2000, and 6000 ppm groups at all timepoints compared to time-matched control groups. A significant transcriptomic proliferative response was only observed in 6000 ppm exposed mice at 90 days. Differential gene expression and pathway enrichment analysis results suggest 600 ppm as a potential threshold concentration for hepatic transcriptomic response to 1,4-dioxane in female mice.
