Wheat gene Sr60 encodes a protein with two putative kinase domains that confers resistance to stem rust. Issue 2 (19th October 2019)

• Record Type: Journal Article
• Authors: Chen, Shisheng; Rouse, Matthew N.; Zhang, Wenjun; Zhang, Xiaoqin; Guo, Yan; Briggs, Jordan; Dubcovsky, Jorge
• Is Part Of: New phytologist. Volume 225:Issue 2(2020)
• Page Start: 948
• Page End: 959
• Publication Date: 2019-10-19
• Subjects: kinase proteins -- resistance genes -- Sr60 -- stem rust -- Triticum monococcum -- wheat; Botany -- Periodicals; 580
• DOI: 10.1111/nph.16169
• Languages: English
• ISSNs: 0028-646X

Abstract

Summary: Wheat stem rust, caused by Puccinia graminis Pers. f. sp. tritici ( Pgt ), is a devastating fungal disease threatening global wheat production. The present paper reports the identification of stem rust resistance gene Sr60, a race‐specific gene from diploid wheat Triticum monococcum L. that encodes a protein with two putative kinase domains. This gene, designated as WHEAT TANDEM KINASE 2 ( WTK2 ), confers intermediate levels of resistance to Pgt . WTK2 was identified by map‐based cloning and validated by transformation of a c. 10‐kb genomic sequence including WTK2 into susceptible common wheat variety Fielder ( Triticum aestivum L.). Transformation of Fielder with WTK2 was sufficient to confer Pgt resistance. Sr60 transcripts were transiently upregulated 1 d post‐inoculation with Pgt, but not in mock‐inoculated plants. The upregulation of Sr60 was associated with stable upregulation of several pathogenesis‐related genes. The Sr60 ‐resistant haplotype found in T. monococcum was not found in polyploid wheat, suggesting an opportunity to introduce a novel resistance gene. Sr60 was successfully introgressed into hexaploid wheat, and we developed a diagnostic molecular marker to accelerate its deployment and pyramiding with other resistance genes. The cloned Sr60 also can be a useful component of transgenic cassettes including other resistance genes with complementary resistance profiles.