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Ca2+/calmodulin regulates salicylic-acid-mediated plant immunity

Abstract

Intracellular calcium transients during plant–pathogen interactions are necessary early events leading to local and systemic acquired resistance1. Salicylic acid, a critical messenger, is also required for both of these responses2,3, but whether and how salicylic acid level is regulated by Ca2+ signalling during plant–pathogen interaction is unclear. Here we report a mechanism connecting Ca2+ signal to salicylic-acid-mediated immune response through calmodulin, AtSR1 (also known as CAMTA3), a Ca2+/calmodulin-binding transcription factor, and EDS1, an established regulator of salicylic acid level. Constitutive disease resistance and elevated levels of salicylic acid in loss-of-function alleles of Arabidopsis AtSR1 suggest that AtSR1 is a negative regulator of plant immunity. This was confirmed by epistasis analysis with mutants of compromised salicylic acid accumulation and disease resistance. We show that AtSR1 interacts with the promoter of EDS1 and represses its expression. Furthermore, Ca2+/calmodulin-binding to AtSR1 is required for suppression of plant defence, indicating a direct role for Ca2+/calmodulin in regulating the function of AtSR1. These results reveal a previously unknown regulatory mechanism linking Ca2+ signalling to salicylic acid level.

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Figure 1: The Atsr1-1 mutant shows sensitized defence responses.
Figure 2: The pleiotropic phenotype of Atsr1-1 is dependent on salicylic acid.
Figure 3: AtSR1 is involved in transcriptional regulation of EDS1.
Figure 4: Repression of immune response by AtSR1 is regulated by Ca 2+ /CaM.

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References

  1. Lecourieux, D., Ranjeva, R. & Pugin, A. Calcium in plant defence-signalling pathways. New Phytol. 171, 249–269 (2006)

    Article  CAS  Google Scholar 

  2. Durrant, W. E. & Dong, X. Systemic acquired resistance. Annu. Rev. Phytopathol. 42, 185–209 (2004)

    Article  CAS  Google Scholar 

  3. Nimchuk, Z., Eulgem, T., Holt, B. F. & Dangl, J. L. Recognition and response in the plant immune system. Annu. Rev. Genet. 37, 579–609 (2003)

    Article  CAS  Google Scholar 

  4. Yang, T. & Poovaiah, B. W. An early ethylene up-regulated gene encoding a calmodulin-binding protein involved in plant senescence and death. J. Biol. Chem. 275, 38467–38473 (2000)

    Article  CAS  Google Scholar 

  5. Reddy, A. S., Reddy, V. S. & Golovkin, M. A calmodulin binding protein from Arabidopsis is induced by ethylene and contains a DNA-binding motif. Biochem. Biophys. Res. Commun. 279, 762–769 (2000)

    Article  CAS  Google Scholar 

  6. Yang, T. & Poovaiah, B. W. A calmodulin-binding/CGCG box DNA-binding protein family involved in multiple signaling pathways in plants. J. Biol. Chem. 277, 45049–45058 (2002)

    Article  CAS  Google Scholar 

  7. Bouche, N., Scharlat, A., Snedden, W., Bouchez, D. & Fromm, H. A novel family of calmodulin-binding transcription activators in multicellular organisms. J. Biol. Chem. 277, 21851–21861 (2002)

    Article  CAS  Google Scholar 

  8. Han, J. et al. The fly CAMTA transcription factor potentiates deactivation of rhodopsin, a G protein-coupled light receptor. Cell 127, 847–858 (2006)

    Article  CAS  Google Scholar 

  9. Song, K. et al. The transcriptional coactivator CAMTA2 stimulates cardiac growth by opposing class II histone deacetylases. Cell 125, 453–466 (2006)

    Article  CAS  Google Scholar 

  10. Ryals, J. A. et al. Systemic acquired resistance. Plant Cell 8, 1809–1819 (1996)

    Article  CAS  Google Scholar 

  11. Lorrain, S., Vailleau, F., Balague, C. & Roby, D. Lesion mimic mutants: keys for deciphering cell death and defense pathways in plants? Trends Plant Sci. 8, 263–271 (2003)

    Article  CAS  Google Scholar 

  12. Alvarez, M. E. et al. Reactive oxygen intermediates mediate a systemic signal network in the establishment of plant immunity. Cell 92, 773–784 (1998)

    Article  CAS  Google Scholar 

  13. Bieri, S. et al. RAR1 positively controls steady state levels of barley MLA resistance proteins and enables sufficient MLA6 accumulation for effective resistance. Plant Cell 16, 3480–3495 (2004)

    Article  CAS  Google Scholar 

  14. Holt, B. F., Belkhadir, Y. & Dangl, J. L. Antagonistic control of disease resistance protein stability in the plant immune system. Science 309, 929–932 (2005)

    Article  ADS  CAS  Google Scholar 

  15. Heil, M. & Baldwin, I. T. Fitness costs of induced resistance: emerging experimental support for a slippery concept. Trends Plant Sci. 7, 61–67 (2002)

    Article  CAS  Google Scholar 

  16. Mauch, F. et al. Manipulation of salicylate content in Arabidopsis thaliana by the expression of an engineered bacterial salicylate synthase. Plant J. 25, 67–77 (2001)

    Article  CAS  Google Scholar 

  17. Yang, S. & Hua, J. A haplotype-specific resistance gene regulated by BONZAI1 mediates temperature-dependent growth control in Arabidopsis . Plant Cell 16, 1060–1071 (2004)

    Article  CAS  Google Scholar 

  18. Clough, S. J. et al. The Arabidopsis dnd1 ‘defense, no death’ gene encodes a mutated cyclic nucleotide-gated ion channel. Proc. Natl Acad. Sci. USA 97, 9323–9328 (2000)

    Article  ADS  CAS  Google Scholar 

  19. Petersen, M. et al. Arabidopsis map kinase 4 negatively regulates systemic acquired resistance. Cell 103, 1111–1120 (2000)

    Article  CAS  Google Scholar 

  20. Wiermer, M., Feys, B. J. & Parker, J. E. Plant immunity: the EDS1 regulatory node. Curr. Opin. Plant Biol. 8, 383–389 (2005)

    Article  CAS  Google Scholar 

  21. Nawrath, C., Heck, S., Parinthawong, N. & Metraux, J. P. EDS5, an essential component of salicylic acid-dependent signaling for disease resistance in Arabidopsis, is a member of the MATE transporter family. Plant Cell 14, 275–286 (2002)

    Article  CAS  Google Scholar 

  22. Wildermuth, M. C., Dewdney, J., Wu, G. & Ausubel, F. M. Isochorismate synthase is required to synthesize salicylic acid for plant defence. Nature 414, 562–565 (2001)

    Article  ADS  CAS  Google Scholar 

  23. Xing, D. & Chen, Z. Effects of mutations and constitutive overexpression of EDS1 and PAD4 on plant resistance to different types of microbial pathogens. Plant Sci. 171, 251–262 (2006)

    Article  CAS  Google Scholar 

  24. Du, L. & Poovaiah, B. W. Ca2+/calmodulin is critical for brassinosteroid biosynthesis and plant growth. Nature 437, 741–745 (2005)

    Article  ADS  CAS  Google Scholar 

  25. Gleason, C. et al. Nodulation independent of rhizobia induced by a calcium-activated kinase lacking autoinhibition. Nature 441, 1149–1152 (2006)

    Article  ADS  CAS  Google Scholar 

  26. Guo, F.-Q., Okamoto, M. & Crawford, N. M. Identification of a plant nitric oxide synthase gene involved in hormonal signaling. Science 302, 100–103 (2003)

    Article  ADS  CAS  Google Scholar 

  27. Ali, R. et al. Death don’t have no mercy and neither does calcium: Arabidopsis cyclic nucleotide gated channel2 and innate immunity. Plant Cell 19, 1081–1095 (2007)

    Article  CAS  Google Scholar 

  28. Mackey, D., Belkhadir, Y., Alonso, J. M., Ecker, J. R. & Dangl, J. L. Arabidopsis RIN4 is a target of the type III virulence effector AvrRpt2 and modulates RPS2-mediated resistance. Cell 112, 379–389 (2003)

    Article  CAS  Google Scholar 

  29. Kim, M. C. et al. Calmodulin interacts with MLO protein to regulate defence against mildew in barley. Nature 416, 447–451 (2002)

    Article  ADS  CAS  Google Scholar 

  30. Shen, Q. H. et al. Nuclear activity of MLA immune receptors links isolate-specific and basal disease-resistance responses. Science 315, 1098–1103 (2007)

    Article  ADS  CAS  Google Scholar 

  31. Alonso, J. M. et al. Genome-wide insertional mutagenesis of Arabidopsis thaliana . Science 301, 653–657 (2003)

    Article  ADS  Google Scholar 

  32. Du, L. & Chen, Z. Identification of genes encoding receptor-like protein kinases as possible targets of pathogen- and salicylic acid-induced WRKY DNA-binding proteins in Arabidopsis . Plant J. 24, 837–847 (2000)

    Article  CAS  Google Scholar 

  33. Chen, K., Du, L. & Chen, Z. Sensitization of defense responses and activation of programmed cell death by a pathogen-induced receptor-like protein kinase in Arabidopsis . Plant Mol. Biol. 53, 61–74 (2003)

    Article  CAS  Google Scholar 

  34. Thordal-Christensen, H., Zhang, Z., Wei, Y. & Collinge, D. B. Subcellular localization of H2O2 in plants. H2O2 accumulation in papillae and hypersensitive response during the barley—powdery mildew interaction. Plant J. 11, 1187–1194 (1997)

    Article  CAS  Google Scholar 

  35. Yu, I. C., Parker, J. & Bent, A. F. Gene-for-gene disease resistance without the hypersensitive response in Arabidopsis dnd1 mutant. Proc. Natl Acad. Sci. USA 95, 7819–7824 (1998)

    Article  ADS  CAS  Google Scholar 

  36. Clarke, J. D., Volko, S. M., Ledford, H., Ausubel, F. M. & Dong, X. Roles of salicylic acid, jasmonic acid, and ethylene in cpr-induced resistance in Arabidopsis . Plant Cell 12, 2175–2190 (2000)

    Article  CAS  Google Scholar 

  37. Timmermans, M. C., Maliga, P., Vieira, J. & Messing, J. The pFF plasmids: cassettes utilising CaMV sequences for expression of foreign genes in plants. J. Biotechnol. 14, 333–344 (1990)

    Article  CAS  Google Scholar 

  38. Du, L. & Poovaiah, B. W. A novel family of Ca2+/calmodulin-binding proteins involved in transcriptional regulation: Interaction with fsh/Ring3 class transcription activators. Plant Mol. Biol. 54, 549–569 (2004)

    Article  CAS  Google Scholar 

  39. Yoo, S.-D., Cho, Y.-H. & Sheen, J. Arabidopsis mesophyll protoplasts: a versatile cell system for transient gene expression analysis. Nature Protocols 2, 1565–1572 (2007)

    Article  CAS  Google Scholar 

  40. Hernandez, J. M., Feller, A., Morohashi, K., Frame, K. & Grotewold, E. The basic helix loop helix domain of maize R links transcriptional regulation and histone modifications by recruitment of an EMSY-related factor. Proc. Natl Acad. Sci. USA 104, 17222–17227 (2007)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

Constructs and transgenic lines produced in this research are available on request. This research was supported by United States Department of Agriculture grants 2002-00741, 2005-01107 and 2008-01034, National Science Foundation grants MCB-0424898, MCB-0424895, DBI 0743097 and IOS-0642146, Colorado Sate University Academic Enrichment Program grant 180470, Office of Naval Research N0014-08-1-0470 and the Washington State University Agricultural Research Center. We also thank I. Day for her comments on the manuscript and A. Mochel for her help in preparing the manuscript.

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Correspondence to B. W. Poovaiah.

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Du, L., Ali, G., Simons, K. et al. Ca2+/calmodulin regulates salicylic-acid-mediated plant immunity. Nature 457, 1154–1158 (2009). https://doi.org/10.1038/nature07612

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