Skip to main content
ISMPMI Congress 2025 Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.

Poster

Session: Session 1 Presenting Authors at Posters (Evens)

P-002 - A pair of TIR-NLR receptors in Solanaceae plants recognizes an effector from Xanthomonas citri

Tuesday, July 15, 2025
09:55 - 11:30  
Location: Confex Hall 3
Extracellular & Intracellular non-self recognition & signaling

    Presenting Author(s)

  • FM

    Fernando Matias, MS (he/him/his)

    Plant physiology and biochemistry
    University of Sao Paulo/"Luiz de Queiroz" College of Agriculture
    Piracicaba, Sao Paulo, Brazil

    • Author(s)

  • CC

    Caio Vinícius Cardoso Mendes

    Ph.D Student
    University of Sao Paulo/"Luiz de Queiroz" College of Agriculture
    Piracicaba, SP, BRAZIL

  • RW

    Rufeng Wang

    M.Sc
    CAS Center for Excellence in Molecular Plant Science
    Shanghai, Shanghai, China (People's Republic)

  • AN

    Amanda Nicolau Minetto

    Ph.D student
    University of Sao Paulo/"Luiz de Queiroz" College of Agriculture
    Piracicaba, Sao Paulo, Brazil

  • EW

    Eliza Walthers

    M.Sc
    Colorado State University
    Fort Collins, Colorado, United States

  • LW

    Li Wan

    CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences
    Shanghai, CHINA

  • MN

    Marc Nishimura

    Professor
    Colorado State University
    Fort Collins, Colorado, United States

  • PT

    Paulo Teixeira (he/him/his)

    Assistant Professor
    University of Sao Paulo/
    Piracicaba, Sao Paulo, Brazil

Plants are constantly exposed to pathogens, yet only a few successfully colonize their tissues and cause disease. Even highly virulent pathogens for one species are often harmless to others. This broad-spectrum immunity, known as non-host resistance (NHR), relies on multiple factors, including immune receptors. Using the citrus pathogen Xanthomonas citri subsp. citri as a model, we are investigating the role of intracellular NLR (Nucleotide-Binding Leucine-Rich Repeat) receptors in NHR. We identified a pair of TIR-NLR receptors in Nicotiana benthamiana that are required for recognizing the effector XopAZ. These receptors, RAZ1 and RAZ2 (Recognition of XopAZ-1 and -2), are highly conserved across Solanaceous plants, suggesting a widespread recognition mechanism. Additionally, XopAZ is prevalent in Xanthomonas species, indicating its evolutionary importance in plant-pathogen interactions. XopAZ contains an FK506-binding protein (FKBP) domain with peptidyl-prolyl isomerase activity (PPIase), which facilitates protein folding. Biochemical and genetic assays confirmed its enzymatic function and demonstrated that recognition by RAZ receptors requires PPIase activity. Both RAZ receptors can self-associate and interact with each other. Based on these findings, we propose that the RAZ receptors detect exogenous PPIase activity as a trigger for immune activation, unveiling a novel mechanism in NLR function.