The Pythium periplocum elicitin PpEli2 confers broad-spectrum disease resistance by triggering a novel receptor-dependent immune pathway in plants

Abstract

Elicitins are microbe-associated molecular patterns produced by oomycetes to elicit plant defense. It is still unclear whether elicitins derived from non-pathogenic oomycetes can be used as bioactive molecules for disease control. Here, for the first time we identify and characterize an elicitin named PpEli2 from the soil-borne oomycete Pythium periplocum, which is a non-pathogenic mycoparasite colonizing the root ecosystem of diverse plant species. Perceived by a novel cell surface receptor-like protein, REli, that is conserved in various plants (e.g. tomato, pepper, soybean), PpEli2 can induce hypersensitive response cell death and an immunity response in Nicotiana benthamiana. Meanwhile, PpEli2 enhances the interaction between REli and its co-receptor BAK1. The receptor-dependent immune response triggered by PpEli2 is able to protect various plant species against Phytophthora and fungal infections. Collectively, our work reveals the potential agricultural application of non-pathogenic elicitins and their receptors in conferring broad-spectrum resistance for plant protection.

Acknowledgements

We thank Dr Zhiyuan Yin (Nanjing Agricultural University) for kind help. This work was supported by the National Natural Science Foundation of China (32272495, 31801715, 31721004) and the Natural Science Foundation of Jiangsu Province (BK20220147).

Author contributions

M.J. and D.D. designed this work. M.J., K.Y. and H.P. wrote the manuscript and performed data analysis. K.Y., Y.W., D.S., R.J., Y.D., Y.Z., D.L., J.L., and X.R. performed the experiments.

Data availability

The data generated herein to support the results of this study are presented in the paper and its Supplementary Information files. Moreover, the generated and analyzed datasets of this study are available from the corresponding authors upon request.

Conflict of interest

The authors declare that they have no competing and conflict interests.

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