Submitted to: Patent Application
Publication Type: Patent Application
Publication Acceptance Date: 5/28/2002
Publication Date: 5/28/2002
Citation: Wise, R.P., Schulze-Lefert, P., Zhou, F., Kurth, J., Halterman, D.A., Wei, F., Elliot, C. 2002. Resistance gene. Patent Application. U.S. Patent 10/148,351.
Technical Abstract: The barley Mla locus confers multiple resistance specificities to the obligate fungal biotroph, Blumeria (=Erysiphe) graminis f. sp. hordei. Interspersed within the 240-kb Mla complex are three families of resistance gene homologs (RGHs). Probes from the Mla-RGH1 family were used to identify three classes of cDNAs. The first class is predicted to encode a full-length CC-NBS-LRR protein and the other two classes contain alternatively spliced, truncated variants. Utilizing a cosmid that contains a gene corresponding to the full-length candidate cDNA, a single-cell expression assay was used to demonstrate complementation of AvrMla6-dependent resistance to B. graminis in barley and wheat. This assay was also used to substantiate previous genetic data that the Mla6 allele requires the signaling pathway component, Rar1, for function. Computational analysis of Mla6 and the Rar1-independent, Mla1 protein reveals 91.2% sequence identity and shows that the LRR domain is subject to diversifying selection. Our findings demonstrate that highly related CC-NBS-LRR proteins encoded by alleles of the Mla locus can dictate similar powdery mildew resistance phenotypes yet still require distinct downstream signaling components.