Exposure to the lampricide 3‐trifluoromethyl‐4‐nitrophenol results in increased expression of carbohydrate transporters in Saccharomyces cerevisiae

Abstract

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is used to control sea lamprey (Petromyzon marinus) populations in freshwater lakes. While TFM can have sublethal and lethal effects, little is known about gene expression changes with TFM exposure. Microarray analysis was used to determine differential gene expression over 4 hours of exposure in S. cerevisiae. Among the most significantly up regulated genes were regulators of carbohydrate transport including HXT1, HXT3, HXT4, IMA5, MIG2, and YKR075C.

Exposure to the lampricide TFM elicits an environmental stress response in yeast

“…cell wall bioassembly), these processes were not validated in the restricted experiment, suggesting that these changes may be related to glucose availability. As reported in Hinkle et al (2016), the most significant GO term identified for the restricted dataset was 'carbohydrate metabolism' with hexose transporters being significantly upregulated. However, this was not seen in the unrestricted experiment suggesting that although TFM exposure may make aerobic respiration less efficient, the availability of glucose for uptake by the hexose transporters would allow for anaerobic glycolysis to continue.…”

“…The TFM dose of 0.05 mM (∼10 mg/L) was chosen since it was the highest tested that showed no growth inhibition when cultures of yeast were exposed long term; typical field concentrations are 1.3-1.5X the mean lethal concentration (∼2 mg/L). Cell viability was measured by agar plating and optical density measurement as in Hinkle et al (2016) and there was no change in viability in the TFM treated versus control treatment.…”

“…The experiment as described in the preceding section where cells were grown in glucose-containing YPD media will be referred to as the unrestricted experiment. To validate the results from the unrestricted experiment, a comparison was made to a similar microarray experiment (NCBI Gene Expression Omnibus database accession number GSE74259) that utilized the same yeast strain, treatment durations and TFM dose, but yeast cultures were grown in a restricted medium (forced aerobic metabolism), yeast peptone glycerol ethanol (Hinkle et al 2016). This experiment will be referred to as the restricted experiment.…”

“…The data from a previously published dataset in which yeast were treated with TFM in a restricted (glucose-free) medium (Hinkle et al 2016) were used to validate the findings in the unrestricted (glucose-containing) experiment. Of the 161 genes that were differentially expressed in the unrestricted TFM exposure experiment, 124 of these genes were considered differentially expressed in the restricted experiment (Supplemental Data, Table S2).…”