title: Characterization of a tryptophan 2-monooxygenase gene from Puccinia graminis f. sp. tritici involved in auxin biosynthesis and rust pathogenicity.
abstract: The plant hormone indole-3-acetic acid (IAA) is best known as a regulator of plant growth and development but its production can also affect plant-microbe interactions. Microorganisms, including numerous plant-associated bacteria and several fungi, are also capable of producing IAA. The stem rust fungus Puccinia graminis f. sp. tritici induced wheat plants to accumulate auxin in infected leaf tissue. A gene (Pgt-IaaM) encoding a putative tryptophan 2-monooxygenase, which makes the auxin precursor indole-3-acetamide (IAM), was identified in the P. graminis f. sp. tritici genome and found to be expressed in haustoria cells in infected plant tissue. Transient silencing of the gene in infected wheat plants indicated that it was required for full pathogenicity. Expression of Pgt-IaaM in Arabidopsis caused a typical auxin expression phenotype and promoted susceptibility to the bacterial pathogen Pseudomonas syringae pv. tomato DC3000.
authors.forename: Chuntao
authors.initials: C
authors.lastname: Yin
authors.forename: Jeong-Jin
authors.initials: JJ
authors.lastname: Park
authors.forename: David R
authors.initials: DR
authors.lastname: Gang
authors.forename: Scot H
authors.initials: SH
authors.lastname: Hulbert
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D001487:Basidiomycota / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D015966:Gene Expression Regulation, Fungal; D020868:Gene Silencing; D054884:Host-Pathogen Interactions; D007210:Indoleacetic Acids / Q000032:analysis / Q000378:metabolism*; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D010935:Plant Diseases / Q000382:microbiology*; D010937:Plant Growth Regulators / Q000032:analysis / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D018547:Plant Stems / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D030821:Plants, Genetically Modified; D044224:Pseudomonas syringae / Q000502:physiology; D036226:Seedlings / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D014908:Triticum / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D014774:Virulence
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D006899:Mixed Function Oxygenases; C023204:tryptophan 2-monooxygenase