The receptor kinase FER is a RALF-regulated scaffold controlling plant immune signaling

In plants, perception of invading pathogens involves cell-surface immune receptor kinases. Here, we report that the Arabidopsis SITE-1 PROTEASE (S1P) cleaves endogenous RAPID ALKALINIZATION FACTOR (RALF) propeptides to inhibit plant immunity. This inhibition is mediated by the malectin-like receptor kinase FERONIA (FER), which otherwise facilitates the ligand-induced complex formation of the immune receptor kinases EF-TU RECEPTOR (EFR) and FLAGELLIN-SENSING 2 (FLS2) with their co-receptor BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED KINASE 1 (BAK1) to initiate immune signaling. We show that FER acts as a RALF-regulated scaffold that modulates receptor kinase complex assembly. A similar scaffolding mechanism may…

• EM
  European Molecular Biology Organization
• GC
  Gatsby Charitable Foundation
• DF
  Deutsche Forschungsgemeinschaft

  Award: STE 2448/1
• ÖA
  Österreichischen Akademie der Wissenschaften
• DF
  Directorate for Biological Sciences
• BA
  Biotechnology and Biological Sciences Research Council

  Awards: BBS/E/J/000PR9796, BB/M013499, ALTF 459-2011, BBS/E/J/000PR9795
• ER
  European Research Council