Plant Breeding Institute, School of Life and Environmental Sciences, University of Sydney, Cobbitty, NSW, Australia.
CSIRO Agriculture & Food, Canberra, ACT, Australia.
Nat Commun. 2021 Jun 7;12(1):3378. doi: 10.1038/s41467-021-23738-0.
The re-emergence of stem rust on wheat in Europe and Africa is reinforcing the ongoing need for durable resistance gene deployment. Here, we isolate from wheat, Sr26 and Sr61, with both genes independently introduced as alien chromosome introgressions from tall wheat grass (Thinopyrum ponticum). Mutational genomics and targeted exome capture identify Sr26 and Sr61 as separate single genes that encode unrelated (34.8%) nucleotide binding site leucine rich repeat proteins. Sr26 and Sr61 are each validated by transgenic complementation using endogenous and/or heterologous promoter sequences. Sr61 orthologs are absent from current Thinopyrum elongatum and wheat pan genome sequences, contrasting with Sr26 where homologues are present. Using gene-specific markers, we validate the presence of both genes on a single recombinant alien segment developed in wheat. The co-location of these genes on a small non-recombinogenic segment simplifies their deployment as a gene stack and potentially enhances their resistance durability.
小麦在欧洲和非洲再次出现茎锈病，这突显出持久的抗性基因部署的持续需求。在这里，我们从小麦中分离出 Sr26 和 Sr61，这两个基因都是作为来自高冰草（Thinopyrum ponticum）的异源染色体渗入物独立引入的。突变基因组学和靶向外显子组捕获确定 Sr26 和 Sr61 是独立的单个基因，它们编码不相关的（34.8%）核苷酸结合位点富含亮氨酸重复蛋白。使用内源性和/或异源启动子序列，通过转基因互补验证了 Sr26 和 Sr61 的有效性。Sr61 同源物不存在于当前的长穗偃麦草和小麦泛基因组序列中，而 Sr26 则存在同源物。使用基因特异性标记，我们验证了这两个基因都存在于在小麦中开发的单个重组异源片段上。这些基因在小的非重组片段上的共定位简化了它们作为基因堆叠的部署，并可能增强它们的抗性持久性。
