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Avirulence Genes

  1. Thierry Rouxel,
  2. Marie-Hélène Balesdent

Published Online: 15 JAN 2010

DOI: 10.1002/9780470015902.a0021267

eLS

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How to Cite

Rouxel, T. and Balesdent, M.-H. 2010. Avirulence Genes. eLS. .

Author Information

  1. INRA-Bioger, Thiverval-Grignon, France

Publication History

  1. Published Online: 15 JAN 2010
Table 1. Avirulence proteins from bacteria and their biochemical/effector functions
Avr proteinR geneHost plantPlant cell localizationBiochemical and/or effector function
Source: From Chisholm et al. 2006; Mudgett and White et al. (2005, 2000).
Pseudomonas syringae pv. glycinea
AvrARpg2SoybeanCytoplasmYopJ/AvrRxv family: interaction with plant MAP-kinases?
AvrBRpg1-bSoybeanUnknownKinase: phosphorylation of Rin4; manipulation of host jasmonic acid (JA) pathway
 Rpm1Arabidopsis thalianaUnknown
AvrCRpg3SoybeanUnknownUnknown
Pseudomonas syringae pv. maculicola
AvrRpm1Rpm1A. thalianaInner membrane?Kinase: phosphorylation of Rin4; inhibition of plant basal defence
Pseudomonas syringae pv. pisi
AvrPpiA1Rpm1A. thalianaUnknownUnknown
 R2PeaUnknown 
AvrPpiB1R3PeaUnknownUnknown
AvrPphDR5PeaUnknownUnknown
AvrRps4 (AvrPpiE)Rps4A. thalianaUnknownUnknown
Pseudomonas syringae pv. tomato
AvrPtoPto (and PRF)TomatoInner membraneKinase binding
AvrPtoBPto (and PRF)TomatoUnknownE3 ubiquitine ligase
AvrRpt2Rps2SoybeanUnknownCysteine protease: cleavage of Rin4; manipulation of host JA pathway; interferes with R-mediated defence
 Rps2A. thalianaCytoplasm
AvrRps4Rps4A. thalianaUnknownUnknown
AvrDRpg4SoybeanUnknownEnzyme involved in syringolide synthesis
Pseudomonas syringae pv. phaseolicola
HopAR1 (AvrPphB)Rps5 (and Pbs1)A. thalianaUnknownCysteine protease: cleaves Pbs1 and manipulates host JA pathway
 R3BeanUnknown
HopX (AvrPphE)R2BeanUnknownUnknown
AvrPphFR1BeanUnknownUnknown
Xanthomonas axonopodis pv. vesicatoria
AvrBs1Bs1PepperUnknownYopJ/AvrRxv family
AvrBs2Bs2PepperCytoplasmAgrocipine synthase-like
AvrBs3Bs3PepperNucleusTranscription activator
AvrBs4Bs4TomatoUnknownAvrBs3 family
AvrBsTBsTA. thalianaUnknownYopJ/AvrRxv family; cysteine protease
AvrXv3Xv3TomatoNucleusTranscription activator
AvrXv4Xv4TomatoUnknownYopJ/AvrRxv family; cysteine protease
AvrRxvRxvBeanUnknownYopJ/AvrRxv family
Xanthomonas oryzae pv. oryzae
AvrXa3Xa3RiceUnknownAvrBs3 family
AvrXa5Xa5RiceUnknownAvrBs3 family
AvrXa7Xa7RiceNucleusAvrBs3 family; transcription activator
AvrXa10Xa10RiceProbably nucleusAvrBs3 family; transcription activator
AvrXa21Xa21RiceUnknownUnknown
AvrXa27Xa27RiceProbably nucleusTranscription activator
Xanthomonas campestris pv. armoraciae
Hax3Bs4TomatoUnknownAvrBs3 family
Hax4Bs4TomatoUnknownAvrBs3 family
Xanthomonas campestris pv. malvacearum
AvrB6B1CottonNucleusAvrBs3 family
Xanthomonas oryzae pv. oryzicola
AvrRxo1Rxo1CornUnknownUnknown
Ralstonia solanacearum
PopP2Rrs1-RA. thalianaUnknownYopJ/AvrRxv family
Table 2. Fungal and oomycete avirulence genes known to-date
Avr proteinNb of AA residuesaNb of cysteinesSignal peptidePutative functionLocalization in plantsExpressionRole in virulence/fitnessR gene
  1. a

    Number of amino acid residues in the unprocessed protein.

Source: Dong et al. 2009; Kamoun 2006; Li et al. 2009; Parlange et al. 2009; Qutob et al. 2009; Stergiopoulos and de Wit 2009; van Poppel et al. 2008; Yoshida et al. 2009.
Cladosporium fulvum (host: tomato)
Avr278820Protease inhibitorApoplastIn plantaInhibits Rcr3 and other proteasesCf-2
Avr4135818Chitin-bindingApoplastIn plantaProtects against chitinasesCf-4
Avr4E121610UnknownApoplastIn plantaUnknownHcr9-4E
Avr963623Carboxypeptidase inhibitorApoplastIn plantaUnknownCf-9
Leptosphaeria maculans (host: oilseed rape)
AvrLm1205122UnknownProbably in cytoplasmOver-expressed in plantaUnknown; weakly involved in fitnessRlm1
AvrLm6144620UnknownProbably in apoplastIn plantaUnknownRlm6
AvrLm4-7143821UnknownProbably in apoplastStrongly over-expressed in plantaUnknown; involved in fitnessRlm4 and Rlm7
Fusarium oxysporum f. sp. lycopersici (host: tomato)
Avr1 (Six4)242617UnknownXylemIn plantaSuppression of I-1- and I-2-mediated resistanceI
Avr2163219UnknownXylem (translocated in cytoplasm?)In plantaUnknownI-2
Avr3 (Six1)284821UnknownXylemStimulated by living cellsAggressiveness determinantI-3
Magnaporthe oryzae (host: rice)
Avr-Pita224816MetalloproteaseCytoplasmIn plantaNone knownPi-ta
Pwl1 to Pwl3137 to 1470, 1 or 221 or 23Glycin-rich hydrophilic proteinProbably in apoplastUnknownUnknownAvirulence towards weeping lovegrass
Ace1403543nonePKS/NRPSFungal appressoriumExpressed in appressoriumUnknownPi33
AvrPiz-t108?18UnknownUnknownUnknownUnknownPiz-t
AvrPia85219UnkwownCytoplasmOver-expression in plantaUnknownPia
AvrPii70319Similarity to the C2H2 zinc finger motifCytoplasmOver-expression in plantaUnknownPii
Avr-Pik/km/kp113321UnknownCytoplasmOver-expression in plantaUnknownPik, Pik-m and Pik-p
Rhynchosporium secalis (host: barley)
Nip1821022Nonspecific toxinProbably in apoplastIn vitroInduces cell necrosisRrs-1
Blumeria graminis f. sp. hordei (host: barley)
Avra102864noneUnknownProbably in cytoplasmUnknownUnknownMla10
Avrk11773noneUnknownProbably in cytoplasmUnknownUnknownMlk1
Melampsora lini (host: flax)
AvrL567150123UnknownCytoplasmExpressed in haustoriaUnknownL5, L6 and L7
AvrM314128UnknownCytoplasmExpressed in haustoriaUnknownM
AvrP1231171123Serine proteaseCytoplasmExpressed in haustoriaUnknownP, P1, P2 and P3
AvrP495728Cystine knotted peptideCytoplasmExpressed in haustoriaUnknownP4
Hyaloperonospora parasitica (host: Arabidopsis thaliana)
Atr1NdWsB311215RXLR domain for translocationCytoplasmUnknownUnknownRpp1Nd and Rpp1-WsB
Atr13187019RXLR domain for translocationCytoplasmOver-expressed in plantaUnknownRpp13
Phytophthora sojae (host: soybean)
Avr1b-1138121RXLR domain for translocationCytoplasmExpressed during early stages of plant infectionSuppresses plant deathRps1b
Avr1a122024RXLR–dEER domain for translocation; W-like domainCytoplasmIn plantaUnknownRps1a
Avr3a111–119020RXLR–dEER domain for translocation; W-like domainCytoplasmIn plantaUnknownRps3a
Avr3c220020RXLR-dEER domain for translocation; W-like domainCytoplasmExpressed during early stages of plant infectionUnknownRps3c
Phytophthora infestans (host: potato)
Avr3a147021RXLR–dEER domain for translocation; manipulation of plant ubiquitin proteasome system?CytoplasmOver-expressed in plantaSuppresses INF1-mediated plant deathR3a
Avr4287024RXLR–dEER domain for translocationCytoplasm ?UnknownUnknownR4
Table 3. List and intrinsic function of currently known viral avirulence genes
Viral avirulence geneVirus speciesVirus genusHost plantPlant resistance gene
Source: Adapted with permission from Janzac 2008.
Coat protein    
 Turnip crinckle virusCarmovirusArabidopsis thalianaHrt
 Cucumber mosaic virus (CMV)CucumovirusA. thalianaRcy1
 Potato virus X (PVX)PotexvirusPotatoNx
 PVXPotexvirusPotatoRx1
 PVXPotexvirusPotatoRx2
 Paprika & pepper mild mottle virusTobamovirusPepperL2
 Pepper mild mottle virusTobamovirusPepperL3
 Pepper mild mottle virusTobamovirusPepperL4
 Tobacco mosaic virus (TMV)TobamovirusTobaccoN
P25 protein    
 Beet necrotic yellow vein virusBenyvirusSugar beetRz-1
RNA-dependent RNA polymerase    
 CMVCucumovirusFrench beanCry
 CMVCucumovirusFrench beanRT4-4
 TMVTobamovirusTomatoTm-1
Movement protein    
 PVXPotexvirusPotatoNb
 TMVTobamovirusTomatoTm-2
 TMVTobamovirusTomatoTm-22
Helicase    
 Turnip mosaic virus (TuMV)PotyvirusOilseed rapeTurB01
 TuMVPotyvirusOilseed rapeTurB05
 TMVTobamovirusTobaccoN
P3 protein    
 TuMVPotyvirusOilseed rapeTurB03
 TuMVPotyvirusOilseed rapeTurB04
 Zucchini yellow mosaic virusPotyvirusZucchiniZym
P3 & HcPro proteins    
 Soybean mosaic virusPotyvirusSoybeanRsv-1
NIa protease    
 Potato virus Y (PVY)PotyvirusPotatoRy
NSs protein    
 Tomato spotted wilt virusTospovirusPepperTsw
Viral protein genome-linked (VPg) (corresponding to a virulence factor)
 Barley yellow mosaic virusBymovirusBarleyRym-4
 PVYPotyvirusPepperPvr21
 PVYPotyvirusPepperPvr22
 PVYPotyvirusTomatoPot-1
 Pea seed-borne mosaic virusPotyvirusPeaSbm-1
 Tobacco vein mottling virusPotyvirusTobaccova
 Bean yellow mosaic virusPotyvirusFrench beanwlv
 Rice yellow mottle virusSobemovirusRiceRymv-1
P3 protein (corresponding to a virulence factor)
 Pea seed-borne mosaic virusPotyvirusPeaSbm-2