The Arabidopsis Protein Phosphatase PP2C38 Negatively Regulates the Central Immune Kinase BIK1

Daniel Couto; Roda Niebergall; Xiangxiu Liang; Christoph A Bücherl; Jan Sklenar; Alberto P Macho; Vardis Ntoukakis; Paul Derbyshire; Denise Altenbach; Dan Maclean; Silke Robatzek; Joachim Uhrig; Frank Menke; Jian-Min Zhou; Cyril Zipfel

doi:10.1371/journal.ppat.1005811

The Arabidopsis Protein Phosphatase PP2C38 Negatively Regulates the Central Immune Kinase BIK1

PLoS Pathog. 2016 Aug 5;12(8):e1005811. doi: 10.1371/journal.ppat.1005811. eCollection 2016 Aug.

Authors

Affiliations

¹ The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom.
² Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
³ Max-Planck-Institute for Plant Breeding Research, Cologne, Germany.
⁴ Botanical Institute III, University of Cologne, Cologne, Germany.

Abstract

Plants recognize pathogen-associated molecular patterns (PAMPs) via cell surface-localized pattern recognition receptors (PRRs), leading to PRR-triggered immunity (PTI). The Arabidopsis cytoplasmic kinase BIK1 is a downstream substrate of several PRR complexes. How plant PTI is negatively regulated is not fully understood. Here, we identify the protein phosphatase PP2C38 as a negative regulator of BIK1 activity and BIK1-mediated immunity. PP2C38 dynamically associates with BIK1, as well as with the PRRs FLS2 and EFR, but not with the co-receptor BAK1. PP2C38 regulates PAMP-induced BIK1 phosphorylation and impairs the phosphorylation of the NADPH oxidase RBOHD by BIK1, leading to reduced oxidative burst and stomatal immunity. Upon PAMP perception, PP2C38 is phosphorylated on serine 77 and dissociates from the FLS2/EFR-BIK1 complexes, enabling full BIK1 activation. Together with our recent work on the control of BIK1 turnover, this study reveals another important regulatory mechanism of this central immune component.

MeSH terms

Arabidopsis / genetics
Arabidopsis / immunology*
Arabidopsis Proteins / genetics
Arabidopsis Proteins / immunology*
NADPH Oxidases / genetics
NADPH Oxidases / immunology
Phosphoprotein Phosphatases / genetics
Phosphoprotein Phosphatases / immunology*
Phosphorylation / genetics
Phosphorylation / immunology
Plant Immunity / physiology*
Protein Kinases / genetics
Protein Kinases / immunology
Protein Serine-Threonine Kinases / genetics
Protein Serine-Threonine Kinases / immunology*

Substances

Arabidopsis Proteins
respiratory burst oxidase homolog D, Arabidopsis
NADPH Oxidases
Protein Kinases
BAK1 protein, Arabidopsis
FLS2 protein, Arabidopsis
BIK1 protein, Arabidopsis
Protein Serine-Threonine Kinases
Phosphoprotein Phosphatases

Grants and funding

This research was funded by The Gatsby Charitable Foundation and The European Research Council (C.Z.), by the Max-Planck Society (SR), and the Chinese Ministry of Science and Technology (2015CB910200; JMZ). D. C. was the recipient of a scholarship (SFRH/BD/79088/2011) from the Portuguese Government (Fundação para a Ciência e a Tecnologia, FCT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.