Pseudomonas HopU1 modulates plant immune receptor levels by blocking the interaction of their mRNAs with GRP7

Valerie Nicaise, Anna Joe, Byeong-ryool Jeong, Christin Korneli, Freddy Boutrot, Isa Westedt, Dorothee Staiger, James R Alfano, Cyril Zipfel

Research output: Contribution to journalArticlepeer-review

115 Citations (Scopus)


Pathogens target important components of host immunity to cause disease. The Pseudomonas syringae type III-secreted effector HopU1 is a mono-ADP-ribosyltransferase required for full virulence on Arabidopsis thaliana. HopU1 targets several RNA-binding proteins including GRP7, whose role in immunity is still unclear. Here, we show that GRP7 associates with translational components, as well as with the pattern recognition receptors FLS2 and EFR. Moreover, GRP7 binds specifically FLS2 and EFR transcripts in vivo through its RNA recognition motif. HopU1 does not affect the protein-protein associations between GRP7, FLS2 and translational components. Instead, HopU1 blocks the interaction between GRP7 and FLS2 and EFR transcripts in vivo. This inhibition correlates with reduced FLS2 protein levels upon Pseudomonas infection in a HopU1-dependent manner. Our results reveal a novel virulence strategy used by a microbial effector to interfere with host immunity.
Original languageEnglish
Pages (from-to)701-12
Number of pages12
JournalThe EMBO Journal
Issue number5
Publication statusPublished - 6 Mar 2013


  • ADP Ribose Transferases
  • Arabidopsis
  • Arabidopsis Proteins
  • Bacterial Proteins
  • Blotting, Western
  • Cell Membrane
  • Electrophoretic Mobility Shift Assay
  • Immunity, Innate
  • Immunoprecipitation
  • Plant Diseases
  • Protein Biosynthesis
  • Protein Kinases
  • Pseudomonas syringae
  • RNA, Messenger
  • RNA, Plant
  • RNA-Binding Proteins
  • Real-Time Polymerase Chain Reaction
  • Receptors, Pattern Recognition
  • Reverse Transcriptase Polymerase Chain Reaction
  • Virulence

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