Eberly College of Arts and Sciences
S. cerevisiae from different environments are subject to a wide range of selective pressures, whether intentional or by happenstance. Chemicals classified by their application, such as herbicides, fungicides and antibiotics, can affect non-target organisms. First marketed as RoundUpTM, glyphosate is the most widely used herbicide. In plants, glyphosate inhibits EPSPS, of the shikimate pathway, which is present in many organisms but lacking in mam- mals. The shikimate pathway produces chorismate which is the precursor to all the aromatic amino acids, para-aminobenzoic acid, and Coenzyme Q10. Crops engineered to be resis- tant to glyphosate contain a homolog of EPSPS that is not bound by glyphosate. Here, we show that S. cerevisiae has a wide-range of glyphosate resistance. Sequence comparison between the target proteins, i.e., the plant EPSPS and the yeast orthologous protein Aro1, predicted that yeast would be resistant to glyphosate. However, the growth variation seen in the subset of yeast tested was not due to polymorphisms within Aro1, instead, it was caused by genetic variation in an ABC multiple drug transporter, Pdr5, and an amino acid permease, Dip5. Using genetic variation as a probe into glyphosate response, we uncovered mecha- nisms that contribute to the transportation of glyphosate in and out of the cell. Taking advan- tage of the natural genetic variation within yeast and measuring growth under different conditions that would change the use of the shikimate pathway, we uncovered a general transport mechanism of glyphosate into eukaryotic cells.
Digital Commons Citation
Rong-Mullins, Xiaoqing; Ravishankar, Apoorva; McNeal, Kristen A.; Longergan, Zachery R.; Biega, Audrey C.; Creamer, J Philip; and Gallagher, Jennifer E G, "Genetic variation in Dip5, an amino acid permease, and Pdr5, a multiple drug transporter, regulates glyphosate resistance in S. cerevisiae" (2017). Faculty & Staff Scholarship. 1270.
Rong-Mullins X, Ravishankar A, McNeal KA, Lonergan ZR, Biega AC, Creamer JP, et al. (2017) Genetic variation in Dip5, an amino acid permease, and Pdr5, a multiple drug transporter, regulates glyphosate resistance in S. cerevisiae. PLoS ONE 12(11): e0187522. https://doi.org/ 10.1371/journal.pone.0187522