title: Arabidopsis downy mildew resistance gene RPP27 encodes a receptor-like protein similar to CLAVATA2 and tomato Cf-9.
abstract: The Arabidopsis Ler-RPP27 gene confers AtSgt1b-independent resistance to downy mildew (Peronospora parasitica) isolate Hiks1. The RPP27 locus was mapped to a four-bacterial artificial chromosome interval on chromosome 1 from genetic analysis of a cross between the enhanced susceptibility mutant Col-edm1 (Col-sgt1) and Landsberg erecta (Ler-0). A Cf-like candidate gene in this interval was PCR amplified from Ler-0 and transformed into mutant Col-rpp7.1 plants. Homozygous transgenic lines conferred resistance to Hiks1 and at least four Ler-0 avirulent/Columbia-0 (Col-0) virulent isolates of downy mildew pathogen. A full-length RPP27 cDNA was isolated, and analysis of the deduced amino acid sequences showed that the gene encodes a receptor-like protein (RLP) with a distinct domain structure, composed of a signal peptide followed by extracellular Leu-rich repeats, a membrane spanning region, and a short cytoplasmic carboxyl domain. RPP27 is the first RLP-encoding gene to be implicated in disease resistance in Arabidopsis, enabling the deployment of Arabidopsis techniques to investigate the mechanisms of RLP function. Homology searches of the Arabidopsis genome, using the RPP27, Cf-9, and Cf-2 protein sequences as a starting point, identify 59 RLPs, including the already known CLAVATA2 and TOO MANY MOUTHS genes. A combination of sequence and phylogenetic analysis of these predicted RLPs reveals conserved structural features of the family.
authors.affiliation: Horticulture Research International, Wellesbourne, Warwick CV35 9EF, United Kingdom. mahmut.tor@hri.ac.uk
authors.forename: Mahmut
authors.initials: M
authors.lastname: Tör
authors.forename: Duncan
authors.initials: D
authors.lastname: Brown
authors.forename: Abigail
authors.initials: A
authors.lastname: Cooper
authors.forename: Alison
authors.initials: A
authors.lastname: Woods-Tör
authors.forename: Kimmen
authors.initials: K
authors.lastname: Sjölander
authors.forename: Jonathan D G
authors.initials: JD
authors.lastname: Jones
authors.forename: Eric B
authors.initials: EB
authors.lastname: Holub
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D005816:Genetic Complementation Test; D007113:Immunity, Innate / Q000235:genetics; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D044742:Peronospora / Q000254:growth & development; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; C401621:CLV2 protein, Arabidopsis; C109609:Cf protein, Lycopersicon esculentum; D018076:DNA, Complementary; D018744:DNA, Plant; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010940:Plant Proteins; C488786:RPP27 protein, Arabidopsis; D011956:Receptors, Cell Surface