title: Positional cloning of ds1, the target leaf spot resistance gene against Bipolaris sorghicola in sorghum.
abstract: Target leaf spot is one of the major sorghum diseases in southern Japan and caused by a necrotrophic fungus, Bipolaris sorghicola. Sorghum resistance to target leaf spot is controlled by a single recessive gene (ds1). A high-density genetic map of the ds1 locus was constructed with simple sequence repeat markers using progeny from crosses between a sensitive variety, bmr-6, and a resistant one, SIL-05, which allowed the ds1 gene to be genetically located within a 26-kb region on the short arm of sorghum chromosome 5. The sorghum genome annotation database for BTx623, for which the whole genome sequence was recently published, indicated a candidate gene from the Leucine-Rich Repeat Receptor Kinase family in this region. The candidate protein kinase gene was expressed in susceptible plants but was not expressed or was severely reduced in resistant plants. The expression patterns of ds1 gene and the phenotype of target leaf spot resistance were clearly correlated. Genomic sequences of this region in parental varieties showed a deletion in the promoter region of SIL-05 that could cause reduction of gene expression. We also found two ds1 alleles for resistant phenotypes with a stop codon in the coding region. The results shown here strongly suggest that the loss of function or suppression of the ds1 protein kinase gene leads to resistance to target leaf spot in sorghum.
authors: National Institute of Agrobiological Sciences, Tsukuba, 305-8602, Japan. shiwak@affrc.go.jp
authors: Hiroyuki
authors: H
authors: Kawahigashi
authors: Shigemitsu
authors: S
authors: Kasuga
authors: Tsuyu
authors: T
authors: Ando
authors: Hiroyuki
authors: H
authors: Kanamori
authors: Jianzhong
authors: J
authors: Wu
authors: Jun-ichi
authors: J
authors: Yonemaru
authors: Takashi
authors: T
authors: Sazuka
authors: Takashi
authors: T
authors: Matsumoto
mesh_terms: D000483:Alleles; D001203:Ascomycota / Q000254:growth & development / Q000472:pathogenicity*; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003001:Cloning, Molecular; D018744:DNA, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005808:Genes, Recessive; D005819:Genetic Markers; D007113:Immunity, Innate; D007564:Japan; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D057865:Plant Immunity; D018515:Plant Leaves / Q000235:genetics* / Q000382:microbiology; D017354:Point Mutation; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D045868:Sorghum / Q000235:genetics* / Q000276:immunology / Q000382:microbiology
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers