Phytocytokine signaling integrates cell surface immunity and nitrogen limitation

Rzemieniewski, J.; Leicher, H.; Lee, H. K.; Broyart, C.; Nayem, S.; Wiese, C.; Maroschek, J.; Camgoez, Z.; Olsson Lalun, V.; Djordjevic, M. A.; Vlot, A. C.; Hueckelhoven, R.; Santiago, J.; Stegmann, M.

doi:10.1101/2022.12.20.521212

bioRxiv · 10.1101/2022.12.20.521212

Phytocytokine signaling integrates cell surface immunity and nitrogen limitation

Rzemieniewski, J.·Leicher, H.·Lee, H. K.·Broyart, C.·Nayem, S.·Wiese, C.·Maroschek, J.·Camgoez, Z.·Olsson Lalun, V.·Djordjevic, M. A.·Vlot, A. C.·Hueckelhoven, R.·Santiago, J.·Stegmann, M.

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Abstract

Plant endogenous signaling peptides shape growth, development and adaptations to biotic and abiotic stress. Here, we identified C-TERMINALLY ENCODED PEPTIDEs (CEPs) as novel immune-modulatory peptides (phytocytokines) in Arabidopsis thaliana. Our data reveals that CEPs induce immune outputs and are required to mount resistance against the leaf-infecting bacterial pathogen Pseudomonas syringae pv. tomato. We show that effective immunity requires CEP perception by tissue-specific CEP RECEPTOR 1 (CEPR1) and CEPR2. Moreover, we identified the related RECEPTOR-LIKE KINASE 7 (RLK7) as a novel CEP4-specific CEP receptor contributing to CEP-mediated immunity, suggesting a complex interplay of multiple CEP ligands and receptors in different tissues during biotic stress. CEPs have a known role in the regulation of root growth and systemic nitrogen (N)-demand signaling. We now provide evidence that CEPs and their receptors promote immunity in an N status-dependent manner, suggesting a previously unknown molecular crosstalk between plant nutrition and cell surface immunity. We propose that CEPs and their receptors are central regulators for the adaptation of biotic stress responses to plant-available resources.

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Rzemieniewski, J., Leicher, H., Lee, H. K., Broyart, C., Nayem, S., Wiese, C., Maroschek, J., Camgoez, Z., Olsson Lalun, V., Djordjevic, M. A., Vlot, A. C., Hueckelhoven, R., Santiago, J., Stegmann, M.. 2022-12-20. Phytocytokine signaling integrates cell surface immunity and nitrogen limitation. https://doi.org/10.1101/2022.12.20.521212

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