Specific resistances against Pseudomonas syringae effectors AvrB and AvrRpm1 have evolved differently in common bean (Phaseolus vulgaris), soybean (Glycine max), and Arabidopsis thaliana.
*In plants, the evolution of specific resistance is poorly understood. Pseudomonas syringae effectors AvrB and AvrRpm1 are recognized by phylogenetically distinct resistance (R) proteins in Arabidopsis thaliana (Brassicaceae) and soybean (Glycine max, Fabaceae). In soybean, these resistances are encoded by two tightly linked R genes, Rpg1-b and Rpg1-r. To study the evolution of these specific resistances, we investigated AvrB- and AvrRpm1-induced responses in common bean (Phaseolus vulgaris, Fabaceae). *Common bean genotypes of various geographical origins were inoculated with P. syringae strains expressing AvrB or AvrRpm1. A common bean recombinant inbred line (RIL) population was used to map R genes to AvrRpm1. *No common bean genotypes recognized AvrB. By contrast, multiple genotypes responded to AvrRpm1, and two independent R genes conferring AvrRpm1-specific resistance were mapped to the ends of linkage group B11 (Rpsar-1, for resistance to Pseudomonas syringae effector AvrRpm1 number 1) and B8 (Rpsar-2). Rpsar-1 is located in a region syntenic with the soybean Rpg1 cluster. However, mapping of specific Rpg1 homologous genes suggests that AvrRpm1 recognition evolved independently in common bean and soybean. *The conservation of the genomic position of AvrRpm1-specific genes between soybean and common bean suggests a model whereby specific clusters of R genes are predisposed to evolve recognition of the same effector molecules.
Chen
Nicolas W G
NWG
Institut de Biologie des Plantes, UMR CNRS 8618, Bat. 630, Université Paris Sud, Orsay, France.
Sévignac
Mireille
M
Institut de Biologie des Plantes, UMR CNRS 8618, Bat. 630, Université Paris Sud, Orsay, France.
Thareau
Vincent
V
Institut de Biologie des Plantes, UMR CNRS 8618, Bat. 630, Université Paris Sud, Orsay, France.
Magdelenat
Ghislaine
G
Genoscope/Commissariat à l'Energie Atomique-Centre National de Séquençage, 2 rue Gaston Crémieux CP5706 91057 Evry Cedex, France.
David
Perrine
P
Institut de Biologie des Plantes, UMR CNRS 8618, Bat. 630, Université Paris Sud, Orsay, France.
Ashfield
Tom
T
Department of Biology, Indiana University, Bloomington, IN, USA.
Innes
Roger W
RW
Department of Biology, Indiana University, Bloomington, IN, USA.
Geffroy
Valérie
V
Institut de Biologie des Plantes, UMR CNRS 8618, Bat. 630, Université Paris Sud, Orsay, France.|Unité Mixte de Recherche de Génétique Végétale, Institut National de la Recherche Agronomique, 91190 Gif-sur-Yvette, France.
D017360:Arabidopsis / Q000235:genetics; D001426:Bacterial Proteins / Q000276:immunology; D005075:Biological Evolution; D002874:Chromosome Mapping; D005798:Genes, Bacterial; D017343:Genes, Plant; D005838:Genotype; D054884:Host-Pathogen Interactions / Q000235:genetics*; D027805:Phaseolus / Q000235:genetics*; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D057865:Plant Immunity / Q000235:genetics*; D044224:Pseudomonas syringae / Q000235:genetics / Q000472:pathogenicity*; D013025:Glycine max / Q000235:genetics
C100931:AvrB protein, Pseudomonas syringae; C502082:AvrRpm1 protein, Pseudomonas syringae; D001426:Bacterial Proteins