title: Brachypodium distachyon line Bd3-1 resistance is elicited by the barley stripe mosaic virus triple gene block 1 movement protein.
abstract: Barley stripe mosaic virus North Dakota 18 (ND18), Beijing (BJ), Xinjiang (XJ), Type (TY) and CV21 strains are unable to infect the Brachypodium distachyon Bd3-1 inbred line, which harbours a resistance gene designated Bsr1, but the Norwich (NW) strain is virulent on Bd3-1. Analysis of ND18 and NW genomic RNA reassortants and RNAβ mutants demonstrates that two amino acids within the helicase motif of the triple gene block 1 (TGB1) movement protein have major effects on their Bd3-1 phenotypes. Resistance to ND18 correlates with an arginine residue at TGB1 position 390 (R(390)) and a threonine at position 392 (T(392)), whereas the virulent NW strain contains lysines (K) at both positions. ND18 TGB1 R390K ((ND)TGB1(R390K)) and (ND)TGB1(T392K) single substitutions, and an (ND)TGB1(R390K,T392K) double mutation resulted in systemic infections of Bd3-1. Reciprocal (ND)TGB1 substitutions into (NW)TGB1 ((NW)TGB1(K390R) and (NW)TGB1(K392T)) failed to affect virulence, implying that K(390) and K(392) compensate for each other. In contrast, an (NW)TGB1(K390R,K392T) double mutant exhibited limited vascular movement in Bd3-1, but developed prominent necrotic streaks that spread from secondary leaf veins. This phenotype, combined with the appearance of necrotic spots in certain ND18 mutants, and necrosis and rapid wilting of Bd3-1 plants after BJ strain ((BJ)TGB1(K390,T392)) inoculations, show that Bd3-1 Bsr1 resistance is elicited by the TGB1 protein and suggest that it involves a hypersensitive response.
authors.affiliation: Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Mi Yeon
authors.initials: MY
authors.lastname: Lee
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Lijie
authors.initials: L
authors.lastname: Yan
authors.affiliation: Laboratory of Genetics, Department of Plant Sciences, Wageningen University, 6700 AH Wageningen, The Netherlands.|Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Florien A
authors.initials: FA
authors.lastname: Gorter
authors.affiliation: Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Brian Y T
authors.initials: BYT
authors.lastname: Kim
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.|Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Grindheim
authors.affiliation: Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Uma
authors.initials: U
authors.lastname: Ganesan
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Chenggui
authors.initials: C
authors.lastname: Han
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Jialin
authors.initials: J
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Agro-Biotechnology, China Agricultural University, Beijing 100193, PR China.
authors.forename: Dawei
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720, USA.
authors.forename: Andrew O
authors.initials: AO
authors.lastname: Jackson
mesh_terms: D000595:Amino Acid Sequence; D058431:Brachypodium / Q000235:genetics* / Q000821:virology*; D017343:Genes, Plant; D001467:Hordeum / Q000821:virology*; D008969:Molecular Sequence Data; D009029:Mosaic Viruses / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity* / Q000502:physiology; D016297:Mutagenesis, Site-Directed; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics / Q000821:virology; D053830:Plant Viral Movement Proteins / Q000235:genetics* / Q000502:physiology; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D017361:Viral Nonstructural Proteins / Q000235:genetics* / Q000502:physiology; D014774:Virulence / Q000235:genetics / Q000502:physiology
chemical_list: D053830:Plant Viral Movement Proteins; D016601:RNA-Binding Proteins; D017361:Viral Nonstructural Proteins; C103801:betab protein, barley stripe mosaic virus