xopAC-triggered immunity against Xanthomonas depends on Arabidopsis receptor-like cytoplasmic kinase genes PBL2 and RIPK.
Xanthomonas campestris pv. campestris (Xcc) colonizes the vascular system of Brassicaceae and ultimately causes black rot. In susceptible Arabidopsis plants, XopAC type III effector inhibits by uridylylation positive regulators of the PAMP-triggered immunity such as the receptor-like cytoplasmic kinases (RLCK) BIK1 and PBL1. In the resistant ecotype Col-0, xopAC is a major avirulence gene of Xcc. In this study, we show that both the RLCK interaction domain and the uridylyl transferase domain of XopAC are required for avirulence. Furthermore, xopAC can also confer avirulence to both the vascular pathogen Ralstonia solanacearum and the mesophyll-colonizing pathogen Pseudomonas syringae indicating that xopAC-specified effector-triggered immunity is not specific to the vascular system. In planta, XopAC-YFP fusions are localized at the plasma membrane suggesting that XopAC might interact with membrane-localized proteins. Eight RLCK of subfamily VII predicted to be localized at the plasma membrane and interacting with XopAC in yeast two-hybrid assays have been isolated. Within this subfamily, PBL2 and RIPK RLCK genes but not BIK1 are important for xopAC-specified effector-triggered immunity and Arabidopsis resistance to Xcc.
INRA, Laboratoire des Interactions Plantes Micro-organismes (LIPM), UMR 441, Castanet-Tolosan, France.
Endrick
E
Guy
Martine
M
Lautier
Matthieu
M
Chabannes
Brice
B
Roux
Emmanuelle
E
Lauber
Matthieu
M
Arlat
Laurent D
LD
Noël
D017360:Arabidopsis / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D002462:Cell Membrane / Q000201:enzymology / Q000235:genetics; D003593:Cytoplasm / Q000201:enzymology / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D054884:Host-Pathogen Interactions; D008164:Luminescent Proteins / Q000235:genetics; D059828:Plant Cells / Q000378:metabolism / Q000382:microbiology; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D057865:Plant Immunity / Q000235:genetics*; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D044224:Pseudomonas syringae / Q000502:physiology; D043368:Ralstonia solanacearum / Q000502:physiology; D016959:Xanthomonas campestris / Q000502:physiology*
D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D008164:Luminescent Proteins; C054562:yellow fluorescent protein, Bacteria; D011494:Protein Kinases; C558451:RPM1-induced protein kinase, Arabidopsis; D017346:Protein Serine-Threonine Kinases; C523449:receptor-like protein kinase 2, Arabidopsis