Virulence on Pm4 kinase-based resistance is determined by two divergent wheat powdery mildew effectors
The wheat resistance gene Pm4 encodes a kinase fusion protein and has gained particular attention as it confers race-specific resistance against two major wheat pathogens: powdery mildew and blast. Here we describe the identification of AvrPm4, the mildew avirulence effector recognized by Pm4, using UV mutagenesis, and its functional validation in wheat protoplasts. We show that AvrPm4 directly interacts with and is phosphorylated by Pm4. Using genetic association and quantitative trait locus mapping, we further demonstrate that the evasion of Pm4 resistance by virulent mildew isolates relies on a second fungal component, SvrPm4, which suppresses AvrPm4-induced cell death. Surprisingly, SvrPm4 was previously described as AvrPm1a. We show that SvrPm4, but not its inactive variant svrPm4, is recognized by the nucleotide-binding leucine-rich repeat immune receptor Pm1a. These multiple roles of a single effector provide a new perspective on fungal (a)virulence proteins and their combinatorial interactions with different types of immune receptors.
Authors
- Lukas Kunz (ORCID: https://orcid.org/0000-0002-8155-5408)
- Javier Sánchez-Martín (ORCID: https://orcid.org/0000-0002-0525-6369)
- Victoria Widrig (ORCID: https://orcid.org/0000-0002-1285-3815)
- Marion C. Müller (ORCID: https://orcid.org/0000-0001-5594-2319)
- Aline Herger (ORCID: https://orcid.org/0000-0003-1043-6441)
- Zoe Bernasconi (ORCID: https://orcid.org/0000-0002-1216-6791)
- Megan A. Outram (ORCID: https://orcid.org/0000-0003-4510-3575)
- Jonatan Isaksson (ORCID: https://orcid.org/0000-0003-3934-4241)
- Seraina Schudel (ORCID: https://orcid.org/0000-0003-3999-843X)
- Michel Neidhart (ORCID: https://orcid.org/0000-0002-9656-5967)
- Kyle W. Bender (ORCID: https://orcid.org/0000-0002-1805-8097)
- Peter N. Dodds (ORCID: https://orcid.org/0000-0003-0620-5923)
- Ursin Stirnemann (ORCID: https://orcid.org/0009-0007-7157-6647)
- María del Pilar (ORCID: https://orcid.org/0000-0002-1956-3730)
- Sebastian Rösli
- Cyril Zipfel
- Melania Figueroa
Institutions
- University of East Anglia (GB)
- Universidad de Salamanca (ES)
- University of Zurich (CH)
- Sainsbury Laboratory (GB)
- Agriculture and Food (AU)
- Technical University of Munich (DE)
Publication Details
- Journal
- Nature Plants
- Published
- 2026-01-12
- DOI
- https://doi.org/10.1038/s41477-025-02180-w
- Citations
- 3
- Primary Topic
- Wheat and Barley Genetics and Pathology
- Type
- article
- Field-Weighted Citation Impact
- 94.02
Funders
- National Science Foundation
- European Commission
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Universität Zürich
- Agencia Estatal de Investigación