The Pseudomonas syringae type III effector AvrRpt2 promotes virulence independently of RIN4, a predicted virulence target in Arabidopsis thaliana.

  title={The Pseudomonas syringae type III effector AvrRpt2 promotes virulence independently of RIN4, a predicted virulence target in Arabidopsis thaliana.},
  author={Melisa T S Lim and Barbara N. Kunkel},
  journal={The Plant journal : for cell and molecular biology},
  volume={40 5},
AvrRpt2, an effector protein from Pseudomonas syringae pv. tomato (Pst), behaves as an avirulence factor that activates resistance in Arabidopsis thaliana lines expressing the resistance gene RPS2. AvrRpt2 can also enhance pathogen fitness by promoting the ability of the bacteria to grow and to cause disease on susceptible lines of A. thaliana that lack functional RPS2. The activation of RPS2 is coupled to the AvrRpt2-induced disappearance of the A. thaliana RIN4 protein. However, the… 

The Pseudomonas syringae avrRpt2 gene contributes to virulence on tomato.

It is shown that a mutant derivative of JL1065 that carries a disruption in avrRpt2 is impaired in its ability to cause disease on tomato (Lycopersicon esculentum), indicating that avr rpt2 also acts as a virulence gene in its native strain on a natural host.

Pseudomonas syringae type III effector AvrRpt2 alters Arabidopsis thaliana auxin physiology

Application of the auxin analog 1-naphthaleneacetic acid promoted disease symptom development in PstDC3000-infected plants, suggesting that elevated auxin levels within host tissue promote Pst DC3000 virulence.

The Pseudomonas syringae effector protein, AvrRPS4, requires in planta processing and the KRVY domain to function.

Transgenic expression of AvrRPS4 in the Arabidopsis rps4 mutant enhances the growth of Pst DC3000 and suppresses PTI (PAMP-triggered immunity), showing that Avr RPS4 promotes virulence in two distinct host plants.

The Erwinia amylovora avrRpt2EA gene contributes to virulence on pear and AvrRpt2EA is recognized by Arabidopsis RPS2 when expressed in pseudomonas syringae.

The results indicated that avrRpt2EA is genetically recognized by the RPS2 disease resistance gene in Arabidopsis when expressed in P. tomato DC3000, and suggested that although distinct pathogens such as E. amylovora and P. syringae may contain similar effector genes, expression and secretion of these effectors can be under specific regulation by the native pathogen.

AvrB mutants lose both virulence and avirulence activities on soybean and Arabidopsis

The results suggest that soybean and Arabidopsis recognize AvrB in the same manner, and that AvRB enzymatic activity is required for its function as an avirulence and virulence effector on two different plant species.

Pseudomonas syringae pv. tomato DC3000: a model pathogen for probing disease susceptibility and hormone signaling in plants.

Genomic analysis shows that Pst DC3000 carries a large repertoire of potential virulence factors, including proteinaceous effectors that are secreted through the type III secretion system and a polyketide phytotoxin called coronatine, which structurally mimics the plant hormone jasmonate (JA).

RIN4-like proteins mediate resistance protein-derived soybean defense against Pseudomonas syringae

These studies suggest that multiple RIN4-like proteins proteins mediate R-mediated signaling, in soybean, which might function as a heteromeric complex in mediating Rpg1-b-derived resistance.

The Cladosporium fulvum Virulence Protein Avr2 Inhibits Host Proteases Required for Basal Defense[W][OA]

It is shown that Avr2 is a genuine virulence factor of C. fulvum that inhibits several Cys proteases required for plant basal defense.

Pseudomonas syringae pv. phaseolicola effector HopF1 inhibits pathogen-associated molecular pattern-triggered immunity in a RIN4-independent manner in common bean (Phaseolus vulgaris).

It is demonstrated that HopF 1 can inhibit pathogen-associated molecular pattern-triggered immunity (PTI) in a susceptible bean cultivar Tendergreen and demonstrated that PvRIN4 orthologs were not the virulence target of HopF1 for inhibiting PTI, but probably for interfering with ETI.

Molecular characterization of proteolytic cleavage sites of the Pseudomonas syringae effector AvrRpt2.

Bioinformatics analysis identified putative Arabidopsis proteins containing sequences similar to the proteolytic cleavage sites conserved in AvrRpt2 and RIN4, and several of these proteins were eliminated in an Avr Rpt2-dependent manner in a transient in planta expression system.



The Pseudomonas syringae type III effector AvrRpt2 functions downstream or independently of SA to promote virulence on Arabidopsis thaliana.

Transgenic plants expressing AvrRpt2 displayed enhanced susceptibility to PstDC3000 strains defective in type III secretion, indicating that enhanced susceptibility of these plants is not because of suppression of defense responses elicited by other type III effectors.

Mutations in the Pseudomonas syringae avrRpt2 gene that dissociate its virulence and avirulence activities lead to decreased efficiency in AvrRpt2-induced disappearance of RIN4.

An alteration in kinetics of RIN4 disappearance triggered by the C-terminal deletion mutants may provide the mechanistic basis for the uncoupling of the avirulence and virulence activities of avrRpt2.

The Pseudomonas syringae avrRpt2 gene product promotes pathogen virulence from inside plant cells.

It is found that tomato strain PstDC3000 expressing avrRpt2 grew to significantly higher levels and often resulted in the formation of more severe disease symptoms in ecotype No-0 plants carrying a mutant RPS2 allele, as well as in two Col-0 mutant lines, cpr5 rps2 and coil rPS2, that exhibit enhanced resistance.

Arabidopsis RIN4 Negatively Regulates Disease Resistance Mediated by RPS2 and RPM1 Downstream or Independent of the NDR1 Signal Modulator and Is Not Required for the Virulence Functions of Bacterial Type III Effectors AvrRpt2 or AvrRpm1

Whereas any pathogen virulence factor may have multiple targets, the perturbation of only one is necessary and sufficient for R activation, it is proposed that many P. syringae type III effectors have more than one target in the host cell.

Functional analysis of the type III effectors AvrRpt2 and AvrRpm1 of Pseudomonas syringae with the use of a single-copy genomic integration system.

A chimeric protein composed of the N terminus of the heterologousAvrRpml effector and the C-terminal effector region of AvrRpt2 was delivered to plant cells, which indicates that the N-terminale region can direct secretion and translocation during an infection, which supports the view that Avr proteins have a modular design.

Arabidopsis mutations at the RPS2 locus result in loss of resistance to Pseudomonas syringae strains expressing the avirulence gene avrRpt2.

Two Arabidopsis thaliana mutants that fail to mount a hypersensitive defense response (HR) when infiltrated with phytopathogenic Pseudomonas strains carrying the avirulence (avr) gene avrRpt2 are isolated and it is shown that RPS2 is required for the elicitation of an HR.

Mutational analysis of the Arabidopsis RPS2 disease resistance gene and the corresponding pseudomonas syringae avrRpt2 avirulence gene.

Ten novel rps2 alleles characterized with mutations in the NBS and the LRR code for point mutations in motifs that are conserved among NBS-LRR resistance genes, including the third LRR, which suggests the importance of these motifs for resistance gene function.