Two virulence determinants of type III effector AvrPto are functionally conserved in diverse Pseudomonas syringae pathovars.
*The Pseudomonas syringae pv. tomato type III effector protein AvrPto has two functional domains that contribute additively to its ability to promote pathogen virulence in susceptible tomato plants and also defense responses in resistant tomato and tobacco genotypes. Here, we test the hypothesis that key amino acid residues in these two domains will be conserved even in sequence-divergent AvrPto proteins expressed by diverse P. syringae pathovars. *We cloned avrPto homologs from diverse P. syringae pathovars and characterized the four most diverse homologs from P. syringae pathovars mori, lachrymans, myricae and oryzae for their virulence activity and ability to elicit resistance in tomato and tobacco. *Key residues within the two AvrPto domains are conserved in three of the four homologs and are required for virulence activity and defense elicitation. AvrPto(oryzae), lacks conserved residues in each domain, but was found to be recognized by a previously unknown resistance gene in both tomato and tobacco. *Our results indicate that the two virulence domains of AvrPto are conserved in diverse pathovars despite the fact these domains are recognized by certain plant species. AvrPto may therefore function in pathovars infecting diverse plant species by targeting conserved host processes.
Nguyen
Hanh P
HP
Boyce Thompson Institute for Plant Research, Ithaca, NY 14853, USA.|Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA.
Yeam
Inhwa
I
Boyce Thompson Institute for Plant Research, Ithaca, NY 14853, USA.
Angot
Aurelie
A
Boyce Thompson Institute for Plant Research, Ithaca, NY 14853, USA.
Martin
Gregory B
GB
Boyce Thompson Institute for Plant Research, Ithaca, NY 14853, USA.|Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY 14853, USA.
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D017343:Genes, Plant; D005838:Genotype; D054884:Host-Pathogen Interactions / Q000235:genetics; D018551:Solanum lycopersicum / Q000235:genetics / Q000382:microbiology; D008969:Molecular Sequence Data; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D057865:Plant Immunity / Q000235:genetics*; D044224:Pseudomonas syringae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000235:genetics / Q000382:microbiology
D001426:Bacterial Proteins; C081695:avrPto protein, Pseudomonas syringae