The Decoy Substrate of a Pathogen Effector and a Pseudokinase Specify Pathogen-Induced Modified-Self Recognition and Immunity in Plants.
In plants, host response to pathogenic microbes is driven both by microbial perception and detection of modified-self. The Xanthomonas campestris effector protein AvrAC/XopAC uridylylates the Arabidopsis BIK1 kinase to dampen basal resistance and thereby promotes bacterial virulence. Here we show that PBL2, a paralog of BIK1, is similarly uridylylated by AvrAC. However, in contrast to BIK1, PBL2 uridylylation is specifically required for host recognition of AvrAC to trigger immunity, but not AvrAC virulence. PBL2 thus acts as a decoy and enables AvrAC detection. AvrAC recognition also requires the RKS1 pseudokinase of the ZRK family and the NOD-like receptor ZAR1, which is known to recognize the Pseudomonas syringae effector HopZ1a. ZAR1 forms a stable complex with RKS1, which specifically recruits PBL2 when the latter is uridylylated by AvrAC, triggering ZAR1-mediated immunity. The results illustrate how decoy substrates and pseudokinases can specify and expand the capacity of the plant immune system.
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing 100101, China.
Guoxun
G
Wang
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France.
Brice
B
Roux
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing 100101, China.
Feng
F
Feng
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France.
Endrick
E
Guy
National Institute of Biological Sciences, Zhongguancun Life Science Park, Changping, Beijing 102206, China.
Lin
L
Li
National Institute of Biological Sciences, Zhongguancun Life Science Park, Changping, Beijing 102206, China.
Nannan
N
Li
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing 100101, China.
Xiaojuan
X
Zhang
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France; Université de Toulouse, UPS, F-31062 Toulouse, France.
Martine
M
Lautier
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France; INPT-Université de Toulouse, ENSAT, Avenue de l'Agrobiopole, Auzeville-Tolosane, F-31326 Castanet-Tolosan, France.
Marie-Françoise
MF
Jardinaud
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France.
Matthieu
M
Chabannes
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France; Université de Toulouse, UPS, F-31062 Toulouse, France.
Matthieu
M
Arlat
National Institute of Biological Sciences, Zhongguancun Life Science Park, Changping, Beijing 102206, China.
She
S
Chen
Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou 570228, China.
Chaozu
C
He
INRA, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 441, F-31326 Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Micro-organismes (LIPM), UMR 2594, F-31326 Castanet-Tolosan, France. Electronic address: laurent.noel@toulouse.inra.fr.
Laurent D
LD
Noël
State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Beijing 100101, China. Electronic address: jmzhou@genetics.ac.cn.
Jian-Min
JM
Zhou
D017360:Arabidopsis / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology*; D054884:Host-Pathogen Interactions; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D010940:Plant Proteins / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D037521:Virulence Factors / Q000378:metabolism*; D016959:Xanthomonas campestris / Q000276:immunology / Q000378:metabolism*
D010940:Plant Proteins; D037521:Virulence Factors