Genetic variation in Dip5, an amino acid permease, and Pdr5, a multiple drug transporter, regulates glyphosate resistance in S. cerevisiae

PLoS One. 2017 Nov 20;12(11):e0187522. doi: 10.1371/journal.pone.0187522. eCollection 2017.

Abstract

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 RoundUp™, 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 mammals. 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 resistant 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 mechanisms that contribute to the transportation of glyphosate in and out of the cell. Taking advantage 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.

MeSH terms

  • 3-Phosphoshikimate 1-Carboxyvinyltransferase / genetics
  • ATP-Binding Cassette Transporters / genetics*
  • Amino Acid Transport Systems / genetics*
  • Genetic Variation
  • Glycine / analogs & derivatives
  • Glycine / toxicity
  • Glyphosate
  • Herbicide Resistance / genetics
  • Herbicides / toxicity
  • Metabolic Networks and Pathways / drug effects
  • Phosphorus-Oxygen Lyases / genetics*
  • Plants / drug effects
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins / genetics*
  • Shikimic Acid / metabolism

Substances

  • ATP-Binding Cassette Transporters
  • Amino Acid Transport Systems
  • DIP5 protein, S cerevisiae
  • Herbicides
  • PDR5 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Shikimic Acid
  • 3-Phosphoshikimate 1-Carboxyvinyltransferase
  • chorismate synthase
  • Phosphorus-Oxygen Lyases
  • Glycine

Grants and funding

West Virginia University PSCoR and West Virginia University Senate Grant provided initial funding. ACB was funded by WVU Summer Undergraduate Research Experience. ZRL was funded by NSF REU-Biological Responses to the Environment from Genes to the Ecosystem DBI 1156627. This work was funded by NSF-MCB 1614573. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.