Submitted to: Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/19/2008
Publication Date: 3/6/2009
Citation: Fu, D., Uauy, C., Distelfeld, A., Blechl, A.E., Epstein, L., Chen, X., Sela, H., Fahima, T., Dubcovsky, J. 2009. A kinase-START gene confers temperature-dependent resistance to wheat stripe rust. Science. 323:1357-1360. Interpretive Summary: Stripe rust is a fungal disease of wheat that causes large production losses in many parts of the world. Host plant resistance is a cost-effective and environmentally friendly way to control the disease. “Slow rusting” resistance genes that retard growth of most of the races of the pathogen are known and have proven to be more durable over time in production agriculture than race-specific resistances. This paper reports the use of traditional genetics, molecular biology, and biotechnology to isolate and verify the identity of the DNA sequences that comprise one such “slow rusting” gene called Yr36. This gene was isolated from wild emmer wheat. The gene’s product contains the spread of fungal infection in wheat plants grown in the temperature range of 25 to 35 degrees Celsius. The Yr36 gene is not found in domesticated bread and pasta wheat varieties. When it was introduced by genetic transformation into a domesticated bread wheat, it conferred resistance to all tested races of stripe rust. The isolation of this gene and determination of its DNA sequence will allow breeders to introduce it into wheat lines that are susceptible to stripe rust and to use precise molecular markers to follow its inheritance. Yr36 is one of the first non-race-specific fungal resistance genes to be cloned. The protein it encodes consists of a novel combination of sensing and kinase domains. Understanding how this protein functions to confer disease resistance could give wheat breeders and farmers new tools for crop protection.
Technical Abstract: Stripe rust is a devastating fungal disease that afflicts wheat in many regions of the world. New races of Puccinia striiformis, the pathogen responsible for this disease, are virulent on most of the known race-specific resistance genes. We report here the map-based cloning of the gene Yr36 (WKS1), which confers non race-specific resistance to stripe rust at relatively high temperatures (25-35 °C). This gene includes a kinase and a putative START lipid binding domain. Five independent mutations and transgenic complementation confirmed that both domains are necessary to confer resistance. Yr36 is present in wild wheat but absent in modern pasta and bread wheat varieties and therefore, can now be used to improve resistance to stripe rust in a broad set of varieties.