Heterologous expression of the yeast Tpo1p or Pdr5p membrane transporters in Arabidopsis confers plant xenobiotic tolerance

Estelle Remy,Paula Duque,Miguel C Teixeira,María Niño-González,Isabel Sá-Correia,Cláudia P Godinho,Tânia R Cabrito

doi:10.1038/s41598-017-04534-7

Abstract

Soil contamination is a major hindrance for plant growth and development. The lack of effective strategies to remove chemicals released into the environment has raised the need to increase plant resilience to soil pollutants. Here, we investigated the ability of two Saccharomyces cerevisiae plasma-membrane transporters, the Major Facilitator Superfamily (MFS) member Tpo1p and the ATP-Binding Cassette (ABC) protein Pdr5p, to confer Multiple Drug Resistance (MDR) in Arabidopsis thaliana. Transgenic plants expressing either of the yeast transporters were undistinguishable from the wild type under control conditions, but displayed tolerance when challenged with the herbicides 2,4-D and barban. Plants expressing ScTPO1 were also more resistant to the herbicides alachlor and metolachlor as well as to the fungicide mancozeb and the Co2+, Cu2+, Ni2+, Al3+ and Cd2+ cations, while ScPDR5-expressing plants exhibited tolerance to cycloheximide. Yeast mutants lacking Tpo1p or Pdr5p showed increased sensitivity to most of the agents tested in plants. Our results demonstrate that the S. cerevisiae Tpo1p and Pdr5p transporters are able to mediate resistance to a broad range of compounds of agricultural interest in yeast as well as in Arabidopsis, underscoring their potential in future biotechnological applications.

Highlights

Along decades, the development of human activities such as industry has led to the release of large amounts of toxic substances into the environment in the form of organic pollutants and heavy metals
We found that heterologous expression of ScTPO1 or ScPDR5 in Arabidopsis resulted in enhanced plant tolerance to both the 2,4-D and barban herbicides and either to the fungicide mancozeb, the herbicides alachlor and metolachlor or to the fungicide cycloheximide, respectively
Despite the increased resistance to this auxinic herbicide, our results indicate that heterologous expression of ScTPO1 and ScPDR5 in Arabidopsis does not affect endogenous auxin metabolism, as primary root (PR) elongation in transgenic plants treated with the native auxin indole-acetic acid (IAA) was similar to that of wild-type plants (Supplementary Fig. S1)

Summary

Introduction

The development of human activities such as industry has led to the release of large amounts of toxic substances into the environment in the form of organic pollutants and heavy metals. A similar effect was observed regarding arsenic resistance when the yeast proton gradient-driven antiporter ScACR3 gene was introduced into Arabidopsis[7] Among the ABC and MFS MDR transporters in the model eukaryote S. cerevisiae, the pleiotropic drug resistance protein 5 (Pdr5p) and the polyamine transporter 1 (Tpo1p), respectively, stand out as the transporters conferring resistance to a wider array of drugs and xenobiotics[9, 10]. Both proteins confer specific resistance to agriculture-relevant stress agents. The S. cerevisiae Pdr5p transporter has been reported to be both under Pdr1p transcriptional control upon exposure to 2,4-D and essential for the resistance to this herbicide[11]

Methods

Results

Conclusion