Polarized Defense Against Fungal Pathogens Is Mediated by the Jacalin-Related Lectin Domain of Modular Poaceae-Specific Proteins

作     者：Denise Weidenbach Lara Esch Claudia Moller Goetz Hensel Jochen Kumlehn Caroline Hofle Ralph Huckelhoven Ulrich Schaffrath 

作者机构：Department of Plant Physiology RWTH Aachen University 52056 Aachen Germany plant Reproductive Biology Leibniz Institute of Plant Genetics and Crop Plant Research 06466 Stadt Seeland/OT Gatersleben Germany Center of Life and Food Sciences Weihenstephan Technische Universitat Munchen 85350 Freising Germany 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2016年第9卷第4期

页      面：514-527页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 09[农学] 071007[理学-遗传学] 0901[农学-作物学] 0902[农学-园艺学] 0836[工学-生物工程] 090102[农学-作物遗传育种] 

基　　金：funded in the framework of the BMBF funding activity "Plant Biotechnology for the future  PLANT 2030" within the project "BarleyFortress" 

主　　题：jacalin-related lectin broad-spectrum disease resistance dirigent Rosetta stone protein rice (Oryza sativa) barley (Hordeum vulgare) 

摘      要：Modular proteins are an evolutionary answer to optimize performance of proteins that physically interact with each other for functionality. Using a combination of genetic and biochemical experiments, we charac-terized the rice protein OsJAC1, which consists of a jacalin-related lectin （JRL） domain predicted to bind mannose-containing oligosaccharides, and a dirigent domain which might function in stereoselective coupling of monolignols. Transgenic overexpression of OsJAC1 in rice resulted in quantitative broad- spectrum resistance against different pathogens including bacteria, oomycetes, and fungi. Overexpression of this gene or its wheat ortholog TAJA1 in barley enhanced resistance against the powdery mildew fungus. Both protein domains of OsJAC1 are required to establish resistance as indicated by single or combined transient expression of individual domains. Expression of artificially separated and fluorescence-tagged protein domains showed that the JRL domain is sufficient for targeting the powdery mildew penetration site. Nevertheless, co-localization of the lectin and the dirigent domain occurred. Phylogenetic analyses re- vealed orthologs of OsJAC1 exclusively within the Poaceae plant family. Dicots, by contrast, only contain proteins with either JRL or dirigent domain（s）. Altogether, our results identify OsJAC1 as a representative of a novel type of resistance protein derived from a plant lineage-specific gene fusion event for better function in local pathogen defense.