Single amino acid change alters specificity of the multi-allelic wheat stem rust resistance locus SR9

Zhang, J. et al. (2023) Single amino acid change alters specificity of the multi-allelic wheat stem rust resistance locus SR9. Nature Communications, 14, 7354. (doi: 10.1038/s41467-023-42747-9) (PMID:37963867) (PMCID:PMC10645757)

Abstract

Most rust resistance genes thus far isolated from wheat have a very limited number of functional alleles. Here, we report the isolation of most of the alleles at wheat stem rust resistance gene locus SR9. The seven previously reported resistance alleles (Sr9a, Sr9b, Sr9d, Sr9e, Sr9f, Sr9g, and Sr9h) are characterised using a synergistic strategy. Loss-of-function mutants and/or transgenic complementation are used to confirm Sr9b, two haplotypes of Sr9e (Sr9e_h1 and Sr9e_h2), Sr9g, and Sr9h. Each allele encodes a highly related nucleotide-binding site leucine-rich repeat (NB-LRR) type immune receptor, containing an unusual long LRR domain, that confers resistance to a unique spectrum of isolates of the wheat stem rust pathogen. The only SR9 protein effective against stem rust pathogen race TTKSK (Ug99), SR9H, differs from SR9B by a single amino acid. SR9B and SR9G resistance proteins are also distinguished by only a single amino acid. The SR9 allelic series found in the B subgenome are orthologs of wheat stem rust resistance gene Sr21 located in the A subgenome with around 85% identity in protein sequences. Together, our results show that functional diversification of allelic variants at the SR9 locus involves single and multiple amino acid changes that recognize isolates of wheat stem rust.

• Item Type: Articles
• Additional Information: J.Z. acknowledges the support from CSIRO CERC Postdoctoral fellowship. S.C. acknowledges support from the Provincial Natural Science Foundation of Shandong (ZR2021MC056 and ZR2021ZD30) and the Open Project Funding of the State Key Laboratory of Crop Stress Adaptation and Improvement. B.B.H.W. acknowledges the Biotechnology and Biological Sciences Research Council (BBSRC) Designing Future Wheat Cross-Institute Strategic Programme (BBS/E/J/000PR9780). Jorge D. acknowledges support from the Howard Hughes Medical Institute (https://www.hhmi.org/) and competitive Grant 2022-68013-36439 (WheatCAP) from the United States Department of Agriculture, National Institute of Food and Agriculture. P.Z., R.Mc., and S.H. acknowledge the support from Grains Research and Development Corporation (GRDC), Australia. M.N.R. acknowledges support from the Durable Rust Resistance in Wheat project funded by the Gates Foundation and UK DFID, a fellowship under the OECD Co-operative Research Programme: Biological Resource Management for Sustainable Agricultural Systems, and the USDA-ARS National Plant Disease Recovery System.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Antoniou Kourounioti, Dr Rea Laila
• Authors: Zhang, J., Nirmala, J., Chen, S., Jost, M., Steuernagel, B., Karafiatova, M., Hewitt, T., Li, H., Edae, E., Sharma, K., Hoxha, S., Bhatt, D., Antoniou Kourounioti, R. L., Dodds, P., Wulff, B. B.H., Dolezel, J., Ayliffe, M., Hiebert, C., McIntosh, R., Dubcovsky, J., Zhang, P., Rouse, M. N., and Lagudah, E.
• College/School: College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
• Journal Name: Nature Communications
• Publisher: Nature Research
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Copyright Holders: Copyright © 2023 The Author(s)
• First Published: First published in Nature Communications 14:7354
• Publisher Policy: Reproduced under a creative commons licence