Natural variation in an NLR pair confers thermostable resistance to a devastating bacterial pathogen

Aoun, N.; Singh, M.; Chacko, J.; Maruta, N.; Griffiths, C.; Dangla, E.; Demont, H.; Carrere, S.; Gouzy, J.; Duflos, R.; Zaffuto, M.; Marchetti, M.; Hancock, A.; Bernoux, M.; Kobe, B.; Deslandes, L.; Roux, F.; Berthome, R.

doi:10.64898/2025.12.15.694456

bioRxiv · 10.64898/2025.12.15.694456

Natural variation in an NLR pair confers thermostable resistance to a devastating bacterial pathogen

Aoun, N.·Singh, M.·Chacko, J.·Maruta, N.·Griffiths, C.·Dangla, E.·Demont, H.·Carrere, S.·Gouzy, J.·Duflos, R.·Zaffuto, M.·Marchetti, M.·Hancock, A.·Bernoux, M.·Kobe, B.·Deslandes, L.·Roux, F.·Berthome, R.

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Abstract

Climate change reshapes host-pathogen interactions by increasing pathogen aggressiveness and weakening plant immune responses, particularly under heat stress. Nucleotide-binding leucine-rich repeat (NLR) immune receptors, key players in pathogen recognition, are altered under elevated temperatures in both plants and mammals, posing a major challenge to disease resistance. In Arabidopsis thaliana, the well-described RPS4/RRS1 NLR pair confers resistance to the worldwide devastating phytopathogenic Ralstonia pseudosolanacearum. Here, by combining the exploration of natural genetic variation with genetic mapping, polymorphism analysis, structural modeling, and functional complementation, we demonstrated that the paucity of full thermostable resistance is primarily associated with a unique RPS4/RRS1 haplotype carrying key substitutions in leucine-rich repeat domains. These findings reveal natural genetic diversity as a source of thermostable resistance, highlighting promising opportunities to engineer climate-resilient plants.

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Aoun, N., Singh, M., Chacko, J., Maruta, N., Griffiths, C., Dangla, E., Demont, H., Carrere, S., Gouzy, J., Duflos, R., Zaffuto, M., Marchetti, M., Hancock, A., Bernoux, M., Kobe, B., Deslandes, L., Roux, F., Berthome, R.. 2025-12-16. Natural variation in an NLR pair confers thermostable resistance to a devastating bacterial pathogen. https://doi.org/10.64898/2025.12.15.694456

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