The plant immune receptors NRG1.1 and ADR1 are calcium influx channels

Jacob, P. M.; Kim, N. H.; Wu, F.; El Kasmi, F. M.; Walton, W. G.; Furzer, O. J.; Lietzen, A. D.; Sunil, S.; Kempthorn, K.; Redinbo, M.; Pei, Z.-M.; Wan, L.; Dangl, J. L.

doi:10.1101/2021.02.25.431980

bioRxiv · 10.1101/2021.02.25.431980

The plant immune receptors NRG1.1 and ADR1 are calcium influx channels

Jacob, P. M.·Kim, N. H.·Wu, F.·El Kasmi, F. M.·Walton, W. G.·Furzer, O. J.·Lietzen, A. D.·Sunil, S.·Kempthorn, K.·Redinbo, M.·Pei, Z.-M.·Wan, L.·Dangl, J. L.

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Abstract

Plant nucleotide-binding leucine-rich repeat receptors (NLRs) regulate immunity and cell death. RPW8 domain-containing "helper" NLRs (RNLs) are required by many "sensor" NLRs. Our crystal structure of the RNL N REQUIREMENT GENE 1.1 (NRG1.1) N-terminal signaling domain resembled that of the resting state plant resistosome-forming HOPZ-ACTIVATED RESISTANCE 1 (ZAR1) and the animal MIXED-LINEAGE KINASE-LIKE (MLKL) cation channel. Active NRG1.1 oligomerized, was enriched in plasma membrane puncta and conferred cytoplasmic Ca2+ influx in plant and human HeLa cells. NRG1.1-dependent Ca2+ influx and cell death were sensitive to Ca2+ channel blockers. Ca2+ influx and cell death mediated by NRG1.1 and ACTIVATED DISEASE RESISTANCE 1 (ADR1), another RNL, required conserved negatively charged N-terminal residues. Thus, RNLs apparently form influx channels to directly regulate cytoplasmic [Ca2+] and consequent cell death. One Sentence SummaryA specific class of plant immune receptors function as calcium-permeable channels upon activation to induce cell death.

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Jacob, P. M., Kim, N. H., Wu, F., El Kasmi, F. M., Walton, W. G., Furzer, O. J., Lietzen, A. D., Sunil, S., Kempthorn, K., Redinbo, M., Pei, Z.-M., Wan, L., Dangl, J. L.. 2021-02-25. The plant immune receptors NRG1.1 and ADR1 are calcium influx channels. https://doi.org/10.1101/2021.02.25.431980

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