Recognition-dependent activation of the Arabidopsis RRS1-R/RPS4 TIR-NLR immune receptor pair
Plant TIR domain-containing proteins exhibit NADase activity upon pathogen effector recognition, creating small molecules that activate defense via EDS1 and its associated proteins. Arabidopsis RPS4 and RRS1 comprise a TIR-NLR immune receptor pair that recognizes multiple effector proteins including AvrRps4 and PopP2. We show here that RPS4 and RRS1 acquire NADase activity upon recognition of a cognate effector. However, both in the presence and absence of effector, RPS4 and RRS1 form an oligomer that does not change in size upon effector provision. Effector-dependent defense activation by RPS4 and RRS1 requires the catalytic glutamate residue and the BB-loop motif of RPS4, which is absent in RRS1 and other RRS1-like TIR domains in Arabidopsis . Oligomerization of RPS4 and RRS1 occurs through multiple domains, but oligomerization does not require enzymatic activity. We propose that conformational changes or reconfiguration within the RPS4/RRS1 oligomer upon effector recognition derepresses the complex for immune activation.
Authors
- Jonathan D. G. Jones (ORCID: https://orcid.org/0000-0002-4953-261X)
- Frank L.H. Menke (ORCID: https://orcid.org/0000-0003-2490-4824)
- Sung Un Huh (ORCID: https://orcid.org/0000-0003-2288-9579)
- Michelle T. Hulin (ORCID: https://orcid.org/0000-0003-4240-5746)
- Maria Sindalovskaya (ORCID: https://orcid.org/0009-0002-0198-7145)
- Guanghao Guo (ORCID: https://orcid.org/0000-0002-1847-0006)
- Hayden Burdett (ORCID: https://orcid.org/0000-0003-4803-9660)
- Jihyeon Choi
- Mark James Banfield (ORCID: https://orcid.org/0000-0001-8921-3835)
- Jan Sklenář (ORCID: https://orcid.org/0000-0003-1858-2574)
- Wenbo Ma (ORCID: https://orcid.org/0000-0001-5569-639X)
- Nitika Mukhi (ORCID: https://orcid.org/0000-0001-5717-7948)
- Eunok Paek (ORCID: https://orcid.org/0000-0003-3655-9749)
- Seungjin Na (ORCID: https://orcid.org/0000-0002-5159-2048)
- He Zhao (ORCID: https://orcid.org/0000-0003-4222-4371)
- Heekyung Ahn (ORCID: https://orcid.org/0000-0002-8884-0156)
- Shania Pin Yin Keh (ORCID: https://orcid.org/0009-0007-0964-8611)
- Lena Knorr (ORCID: https://orcid.org/0000-0001-9664-5708)
Institutions
- John Innes Centre (GB)
- University of East Anglia (GB)
- Kunsan National University (KR)
- Norwich Research Park (GB)
- Sainsbury Laboratory (GB)
- Convergent Science (United States) (US)
- Korea Basic Science Institute (KR)
- Hanyang University (KR)
- Michigan State University (US)
- University of Edinburgh (GB)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2026-10-27
- DOI
- https://doi.org/10.1073/pnas.2611802123
- Primary Topic
- Plant-Microbe Interactions and Immunity
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Royal Society
- Gatsby Charitable Foundation
- Korea Basic Science Institute
- Biotechnology and Biological Sciences Research Council
- Institute for Information and Communications Technology Promotion
- HORIZON EUROPE European Research Council