The ABC transporter ABCG29 is involved in H2O2 tolerance and biocontrol traits in the fungus Clonostachys rosea

Abstract

For successful biocontrol interactions, biological control organisms must tolerate toxic metabolites produced by themselves or plant pathogens during mycoparasitic/antagonistic interactions, by host plant during colonization of the plant, and xenobiotics present in the environment. ATP-binding cassette (ABC) transporters can play a significant role in tolerance of toxic compounds by mediating active transport across the cellular membrane. This paper reports on functional characterization of an ABC transporter ABCG29 in the biocontrol fungus Clonostachys rosea strain IK726. Gene expression analysis showed induced expression of abcG29 during exposure to the Fusarium spp. mycotoxin zearalenone (ZEA) and the fungicides Cantus, Chipco Green and Apron. Expression of abcG29 in C. rosea was significantly higher during C. rosea-C. rosea (Cr-Cr) interaction or in exposure to C. rosea culture filtrate for 2 h, compared to interaction with Fusarium graminearum or 2 h exposure to F. graminearum culture filtrate. In contrast with gene expression data, Delta abcG29 strains did not display reduced tolerance towards ZEA, fungicides or chemical agents known for inducing oxidative, cell wall or osmotic stress, compared to C. rosea WT. The exception was a significant reduction in tolerance to H2O2 (10 mM) in Delta abcG29 strains when conidia were used as an inoculum. The antagonistic ability of Delta abcG29 strains towards F. graminearum, Fusarium oxysporum or Botrytis cinerea in dual plate assays were not different compared with WT. However, in biocontrol assays Delta abcG29 strains displayed reduced ability to protect Arabidopsis thaliana leaves from B. cinerea, and barley seedling from F. graminearum as measured by an A. thaliana detached leaf assay and a barley foot rot disease assay, respectively. These data show that the ABCG29 is dispensable for ZEA and fungicides tolerance, and antagonism but not H2O2 tolerance and biocontrol effects in C. rosea.

Keywords

ABC transporter; Biocontrol; Clonostachys rosea; Fungicide tolerance; Oxidative stress; Zearalenone

Published in

Molecular Genetics and Genomics
2016, volume: 291, number: 2, pages: 677-686
Publisher: SPRINGER HEIDELBERG

SLU Authors

• Dubey, Mukesh

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

• Jensen, Dan Funck

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

• Karlsson, Magnus

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network
AMR: Fungus

UKÄ Subject classification

Microbiology
Agricultural Science
Genetics and Genomics

Publication identifier

• DOI: https://doi.org/10.1007/s00438-015-1139-y

Permanent link to this page (URI)

https://res.slu.se/id/publ/79469