Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>

ABSTRACT The ascomycete Zymoseptoria tritici is the causal agent of Septoria leaf blotch on wheat. Disease control relies mainly on resistant wheat cultivars and on fungicide applications. The fungus displays a high potential to circumvent both methods. Resistance against all unisite fungicides has...

Full description

Bibliographic Details
Main Authors: Selim Omrane, Colette Audéon, Amandine Ignace, Clémentine Duplaix, Lamia Aouini, Gert Kema, Anne-Sophie Walker, Sabine Fillinger
Format: Article
Language:English
Published: American Society for Microbiology 2017-10-01
Series:mSphere
Subjects:
Online Access:https://journals.asm.org/doi/10.1128/mSphere.00393-17
_version_ 1819041664111476736
author Selim Omrane
Colette Audéon
Amandine Ignace
Clémentine Duplaix
Lamia Aouini
Gert Kema
Anne-Sophie Walker
Sabine Fillinger
author_facet Selim Omrane
Colette Audéon
Amandine Ignace
Clémentine Duplaix
Lamia Aouini
Gert Kema
Anne-Sophie Walker
Sabine Fillinger
author_sort Selim Omrane
collection DOAJ
description ABSTRACT The ascomycete Zymoseptoria tritici is the causal agent of Septoria leaf blotch on wheat. Disease control relies mainly on resistant wheat cultivars and on fungicide applications. The fungus displays a high potential to circumvent both methods. Resistance against all unisite fungicides has been observed over decades. A different type of resistance has emerged among wild populations with multidrug-resistant (MDR) strains. Active fungicide efflux through overexpression of the major facilitator gene MFS1 explains this emerging resistance mechanism. Applying a bulk-progeny sequencing approach, we identified in this study a 519-bp long terminal repeat (LTR) insert in the MFS1 promoter, a relic of a retrotransposon cosegregating with the MDR phenotype. Through gene replacement, we show the insert as a mutation responsible for MFS1 overexpression and the MDR phenotype. Besides this type I insert, we found two different types of promoter inserts in more recent MDR strains. Type I and type II inserts harbor potential transcription factor binding sites, but not the type III insert. Interestingly, all three inserts correspond to repeated elements present at different genomic locations in either IPO323 or other Z. tritici strains. These results underline the plasticity of repeated elements leading to fungicide resistance in Z. tritici and which contribute to its adaptive potential. IMPORTANCE Disease control through fungicides remains an important means to protect crops from fungal diseases and to secure the harvest. Plant-pathogenic fungi, especially Zymoseptoria tritici, have developed resistance against most currently used active ingredients, reducing or abolishing their efficacy. While target site modification is the most common resistance mechanism against single modes of action, active efflux of multiple drugs is an emerging phenomenon in fungal populations reducing additionally fungicides’ efficacy in multidrug-resistant strains. We have investigated the mutations responsible for increased drug efflux in Z. tritici field strains. Our study reveals that three different insertions of repeated elements in the same promoter lead to multidrug resistance in Z. tritici. The target gene encodes the membrane transporter MFS1 responsible for drug efflux, with the promoter inserts inducing its overexpression. These results underline the plasticity of repeated elements leading to fungicide resistance in Z. tritici.
first_indexed 2024-12-21T09:28:35Z
format Article
id doaj.art-77e8f915e26d407581fe553b0bd3fda9
institution Directory Open Access Journal
issn 2379-5042
language English
last_indexed 2024-12-21T09:28:35Z
publishDate 2017-10-01
publisher American Society for Microbiology
record_format Article
series mSphere
spelling doaj.art-77e8f915e26d407581fe553b0bd3fda92022-12-21T19:08:49ZengAmerican Society for MicrobiologymSphere2379-50422017-10-012510.1128/mSphere.00393-17Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>Selim Omrane0Colette Audéon1Amandine Ignace2Clémentine Duplaix3Lamia Aouini4Gert Kema5Anne-Sophie Walker6Sabine Fillinger7UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceUMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceUMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceUMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceWageningen University, Plant Research International, Wageningen, The NetherlandsWageningen University, Plant Research International, Wageningen, The NetherlandsUMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceUMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, Thiverval-Grignon, FranceABSTRACT The ascomycete Zymoseptoria tritici is the causal agent of Septoria leaf blotch on wheat. Disease control relies mainly on resistant wheat cultivars and on fungicide applications. The fungus displays a high potential to circumvent both methods. Resistance against all unisite fungicides has been observed over decades. A different type of resistance has emerged among wild populations with multidrug-resistant (MDR) strains. Active fungicide efflux through overexpression of the major facilitator gene MFS1 explains this emerging resistance mechanism. Applying a bulk-progeny sequencing approach, we identified in this study a 519-bp long terminal repeat (LTR) insert in the MFS1 promoter, a relic of a retrotransposon cosegregating with the MDR phenotype. Through gene replacement, we show the insert as a mutation responsible for MFS1 overexpression and the MDR phenotype. Besides this type I insert, we found two different types of promoter inserts in more recent MDR strains. Type I and type II inserts harbor potential transcription factor binding sites, but not the type III insert. Interestingly, all three inserts correspond to repeated elements present at different genomic locations in either IPO323 or other Z. tritici strains. These results underline the plasticity of repeated elements leading to fungicide resistance in Z. tritici and which contribute to its adaptive potential. IMPORTANCE Disease control through fungicides remains an important means to protect crops from fungal diseases and to secure the harvest. Plant-pathogenic fungi, especially Zymoseptoria tritici, have developed resistance against most currently used active ingredients, reducing or abolishing their efficacy. While target site modification is the most common resistance mechanism against single modes of action, active efflux of multiple drugs is an emerging phenomenon in fungal populations reducing additionally fungicides’ efficacy in multidrug-resistant strains. We have investigated the mutations responsible for increased drug efflux in Z. tritici field strains. Our study reveals that three different insertions of repeated elements in the same promoter lead to multidrug resistance in Z. tritici. The target gene encodes the membrane transporter MFS1 responsible for drug efflux, with the promoter inserts inducing its overexpression. These results underline the plasticity of repeated elements leading to fungicide resistance in Z. tritici.https://journals.asm.org/doi/10.1128/mSphere.00393-17antifungal resistancebulk progeny analysisefflux pumpsmultidrug resistancerepeated elementstranscriptional regulation
spellingShingle Selim Omrane
Colette Audéon
Amandine Ignace
Clémentine Duplaix
Lamia Aouini
Gert Kema
Anne-Sophie Walker
Sabine Fillinger
Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
mSphere
antifungal resistance
bulk progeny analysis
efflux pumps
multidrug resistance
repeated elements
transcriptional regulation
title Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
title_full Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
title_fullStr Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
title_full_unstemmed Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
title_short Plasticity of the <italic toggle="yes">MFS1</italic> Promoter Leads to Multidrug Resistance in the Wheat Pathogen <italic toggle="yes">Zymoseptoria tritici</italic>
title_sort plasticity of the italic toggle yes mfs1 italic promoter leads to multidrug resistance in the wheat pathogen italic toggle yes zymoseptoria tritici italic
topic antifungal resistance
bulk progeny analysis
efflux pumps
multidrug resistance
repeated elements
transcriptional regulation
url https://journals.asm.org/doi/10.1128/mSphere.00393-17
work_keys_str_mv AT selimomrane plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT coletteaudeon plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT amandineignace plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT clementineduplaix plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT lamiaaouini plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT gertkema plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT annesophiewalker plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic
AT sabinefillinger plasticityoftheitalictoggleyesmfs1italicpromoterleadstomultidrugresistanceinthewheatpathogenitalictoggleyeszymoseptoriatriticiitalic