A genome‐wide survey reveals abundant rice blast R genes in resistant cultivars. (1st October 2015)

• Record Type: Journal Article
• Authors: Zhang, Xiaohui; Yang, Sihai; Wang, Jiao; Jia, Yanxiao; Huang, Ju; Tan, Shengjun; Zhong, Yan; Wang, Ling; Gu, Longjiang; Chen, Jian‐Qun; Pan, Qinghua; Bergelson, Joy; Tian, Dacheng
• Is Part Of: Plant journal. Volume 84:Number 1(2015:Oct.)
• Page Start: 20
• Page End: 28
• Publication Date: 2015-10-01
• Subjects: Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.12955
• Languages: English
• ISSNs: 0960-7412

Abstract

<abstract abstract-type="main" id="tpj12955-abs-0001"> <title>Summary</title> <p>Plant resistance genes (<italic>R</italic> genes) harbor tremendous allelic diversity, constituting a robust immune system effective against microbial pathogens. Nevertheless, few functional <italic>R</italic> genes have been identified for even the best‐studied pathosystems. Does this limited repertoire reflect specificity, with most <italic>R</italic> genes having been defeated by former pests, or do plants harbor a rich diversity of functional <italic>R</italic> genes, the composite behavior of which is yet to be characterized? Here, we survey 332 <italic>NBS‐LRR</italic> genes cloned from five resistant <italic>Oryza sativa</italic> (rice) cultivars for their ability to confer recognition of 12 rice blast isolates when transformed into susceptible cultivars. Our survey reveals that 48.5% of the 132 <italic>NBS‐LRR</italic> loci tested contain functional rice blast <italic>R</italic> genes, with most <italic>R</italic> genes deriving from multi‐copy clades containing especially diversified loci. Each <italic>R</italic> gene recognized, on average, 2.42 of the 12 isolates screened. The abundant <italic>R</italic> genes identified in resistant genomes provide extraordinary redundancy in the ability of host genotypes to recognize particular isolates. If the same is true for other pathogens, many extant <italic>NBS‐LRR</italic> genes retain functionality. Our success at identifying rice blast <italic>R</italic> genes also validates a highly efficient cloning and screening strategy.</p> </abstract>