title: Receptor-like cytoplasmic kinases integrate signaling from multiple plant immune receptors and are targeted by a Pseudomonas syringae effector.
abstract: Cell-surface-localized plant immune receptors, such as FLS2, detect pathogen-associated molecular patterns (PAMPs) and initiate PAMP-triggered immunity (PTI) through poorly understood signal-transduction pathways. The pathogenic Pseudomonas syringae effector AvrPphB, a cysteine protease, cleaves the Arabidopsis receptor-like cytoplasmic kinase PBS1 to trigger cytoplasmic immune receptor RPS5-specified effector-triggered immunity (ETI). Analyzing the function of AvrPphB in plants lacking RPS5, we find that AvrPphB can inhibit PTI by cleaving additional PBS1-like (PBL) kinases, including BIK1, PBL1, and PBL2. In unstimulated plants, BIK1 and PBL1 interact with FLS2 and are rapidly phosphorylated upon FLS2 activation by its ligand flg22. Genetic and molecular analyses indicate that BIK1, and possibly PBL1, PBL2, and PBS1, integrate immune signaling from multiple immune receptors. Whereas AvrPphB-mediated degradation of one of these kinases, PBS1, is monitored by RPS5 to initiate ETI, this pathogenic effector targets other PBL kinases for PTI inhibition.
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China; State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Xiang
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Zixu
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: Laluk
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Ding
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zou
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Minghui
authors.initials: M
authors.lastname: Gao
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: She
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Tesfaye
authors.initials: T
authors.lastname: Mengiste
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China.
authors.forename: Yuelin
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: National Institute of Biological Sciences, Beijing 102206, China. Electronic address: zhoujianmin@nibs.ac.cn.
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Zhou
mesh_terms: D017360:Arabidopsis / Q000276:immunology* / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D010766:Phosphorylation; D010940:Plant Proteins / Q000378:metabolism*; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D044224:Pseudomonas syringae / Q000472:pathogenicity*; D015398:Signal Transduction; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D010940:Plant Proteins; C465630:RPS5 protein, Arabidopsis; D037521:Virulence Factors; C500179:avrPphB protein, Pseudomonas syringae; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis; C477340:PBS1 protein, Arabidopsis; C509522:BIK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases