A conserved juxtamembrane motif in plant NFR5 receptors is essential for root nodule symbiosis
Establishment of root nodule symbiosis is initiated by the perception of bacterial Nod factor ligands by the plant LysM receptor kinases NFR1 and NFR5. Receptor signaling initiating the symbiotic pathway depends on the kinase activity of NFR1, while the signaling mechanism of the catalytically inactive NFR5 pseudokinase is unknown. Here, we present the crystal structure of the signaling-competent <i>Lotus japonicus</i> NFR5 intracellular domain, comprising the juxtamembrane region and pseudokinase domain. The juxtamembrane region is structurally well defined and forms two α-helices, αA and αA', which contain an exposed hydrophobic motif. We demonstrate that this "juxtamembrane motif" promotes NFR5-NFR5 and NFR1-NFR5 interactions and is essential for symbiotic signaling. Conservation analysis reveals that the juxtamembrane motif is present throughout NFR5-type receptors and is required for symbiosis signaling from barley RLK10, suggesting a conserved and broader function for this motif in plant-microbe symbioses.
Authors
- Damiano Lironi (ORCID: https://orcid.org/0000-0002-6293-4832)
- Alen Trgovcevic (ORCID: https://orcid.org/0000-0001-7709-6803)
- I. Jensen (ORCID: https://orcid.org/0009-0001-7136-3859)
- Thi‐Bich Luu (ORCID: https://orcid.org/0000-0001-8148-6927)
- Kasper R. Andersen (ORCID: https://orcid.org/0000-0002-4415-8067)
- T. Birkefeldt
- Kira Gysel (ORCID: https://orcid.org/0000-0003-4245-9998)
- Henriette Rübsam (ORCID: https://orcid.org/0000-0003-4667-5700)
- Jens Stougaard (ORCID: https://orcid.org/0000-0002-9312-2685)
- Simona Radutoiu (ORCID: https://orcid.org/0000-0002-8841-1415)
- Simon B. Hansen (ORCID: https://orcid.org/0000-0002-0843-3922)
- Christina Krönauer (ORCID: https://orcid.org/0000-0002-3172-5149)
- Magdalini Tsitsikli (ORCID: https://orcid.org/0009-0008-8753-529X)
Institutions
- Aarhus University (DK)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2024-11-04
- DOI
- https://doi.org/10.1073/pnas.2405671121
- Citations
- 7
- Primary Topic
- Legume Nitrogen Fixing Symbiosis
- Type
- article
- Field-Weighted Citation Impact
- 4.20
Funders
- Bill and Melinda Gates Foundation
- VINNOVA
- Svenska Forskningsrådet Formas
- Vetenskapsrådet
- Danmarks Frie Forskningsfond
- Foreign, Commonwealth and Development Office