The Triple Gene Block 1 Movement Protein of the ND18 Strain of Barley Stripe Mosaic Virus is an Avirulence Determinant That Elicits Brachypodium distachyon Bd3-1 resistance
作者单位：Department of Plant & Microbial BiologyUniversity of California-BerkeleyBerkeleyCA 94720USA
会议名称：《中国植物病理学会2012年学术年会》
会议日期：2012年
学科分类：09[农学] 0904[农学-植物保护] 090401[农学-植物病理学]
关 键 词：Barley stripe mosaic virus Brachypodium distachyon resistance ND18 strain avirulence determinants Triple Gene Block 1(TGB1)
摘 要：Barley stripe mosaic virus(BSMV) North Dakota 18(ND18),Norwich(NW),Beijing (BJ),Xinjiang(XJ),Type and CV21 strains elicit different phenotypic responses on Brachypodium distachyon, a cereal grass model for ***18 is unable to infect the Brachypodium Bd3-1 inbred line,which contains a recently mapped resistance gene designated Bsr1(Cui et *** ONE,2012, 7(6);e38333).Along with ND18,the BJ,XJ,Type and CV21 strains also failed to produce visible symptoms or virus on Bd3-1,so it is possible that Bsr1 mediates resistance against all five BSMV strains. In contrast,NW overcomes Bd3-1 resistance and is accompanied by an intense mosaic phenotype and large amounts of *** of ND18 and NW genomic RNAs,and a series of chimeric exchanges within RNAβdemonstrate that Bd3-1 phenotypes are mediated by a region within the helicase motif of *** of this region reveals that the ND18 and NW strains contain divergent amino acids at positions 390,392 and 404 within this region,and that the inability of ND18 and the BJ,XJ,Type and CV21 strains to elicit fully virulent BSMV infections on Bd3-1 correlates with a threonine(T) at position 392(T).The virulent NW strain contains K residues at both the 390 and 392 positions and a glutamate (E) residue at position *** substitutions to swap the ND18 and NW 404 residues failed to affect the respective disease ***,R390K and T392K single exchanges and a R390K/ T392K double mutant in ND18 RNA TGB1 resulted in virulent *** contrast,incorporation of single K390R or K392T mutations into the NW TGB1 protein background did not affect the susceptible disease phenotype,suggesting that the NW K and K residues compensate for each *** contrast, a K390R/K392T double mutant in the NW TGB1 background failed to develop fully systemic infections on Bd3-1,or accumulate detectable viral RNA,but prominent necrotic streaks radiating from the secondary leaf veins were *** experiments in toto