title: Biosynthesis of the halogenated auxin, 4-chloroindole-3-acetic acid.
abstract: Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-acetic acid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-acetic acid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-acetic acid levels as they mature. We also show that the widespread auxin, indole-3-acetic acid, is synthesized by a parallel pathway in pea.
authors.affiliation: School of Plant Science , University of Tasmania, Sandy Bay, Tasmania, Australia 7005.
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Tivendale
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Davidson
authors.forename: Noel W
authors.initials: NW
authors.lastname: Davies
authors.forename: Jason A
authors.initials: JA
authors.lastname: Smith
authors.forename: Marion
authors.initials: M
authors.lastname: Dalmais
authors.forename: Abdelhafid I
authors.initials: AI
authors.lastname: Bendahmane
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Quittenden
authors.forename: Lily
authors.initials: L
authors.lastname: Sutton
authors.forename: Raj K
authors.initials: RK
authors.lastname: Bala
authors.forename: Christine
authors.initials: C
authors.lastname: Le Signor
authors.forename: Richard
authors.initials: R
authors.lastname: Thompson
authors.forename: James
authors.initials: J
authors.lastname: Horne
authors.forename: James B
authors.initials: JB
authors.lastname: Reid
authors.forename: John J
authors.initials: JJ
authors.lastname: Ross
mesh_terms: D053898:Biosynthetic Pathways; D002851:Chromatography, High Pressure Liquid; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000737:chemistry / Q000378:metabolism*; D007211:Indoles / Q000378:metabolism; D007553:Isotope Labeling; D013058:Mass Spectrometry; D009154:Mutation / Q000235:genetics; D018532:Pisum sativum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012015:Reference Standards; D012639:Seeds / Q000235:genetics / Q000254:growth & development; D013237:Stereoisomerism
chemical_list: D007210:Indoleacetic Acids; D007211:Indoles; D010940:Plant Proteins; C096198:4-chloroindole-3-acetic acid; C008122:indol-3-yl pyruvic acid