Arabidopsis AUX1 gene: a permease-like regulator of root gravitropism

• Published in: Science (American Association for the Advancement of Science) 1996-08, Vol.273 (5277), p.948-950
• Main Authors: Bennett, M.J. (University of Warwick, Coventry, UK.), Marchant, A, Green, H.G, May, S.T, Ward, S.P, Millner, P.A, Walker, A.R, Schulz, B, Feldmann, K.A
• Format: Article
• Language: English
• Subjects: 2,4-Dichlorophenoxyacetic Acid - pharmacology; Alleles; Amino Acid Sequence; Amino Acid Transport Systems; Amino acids; Amino Acids - metabolism; Arabidopsis - chemistry; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins; ARABIDOPSIS THALIANA; Auxin; AUXINAS; AUXINE; Auxins; Biological and medical sciences; Biological Transport; Botany; Classical genetics, quantitative genetics, hybrids; Cloning, Molecular; Complementary DNA; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; CRECIMIENTO; CROISSANCE; DNA, Bacterial - genetics; Fundamental and applied biological sciences. Psychology; GENE; GENES; Genes, Plant; Genetic aspects; Genetic Complementation Test; GENETICA; Genetics; Genetics of eukaryotes. Biological and molecular evolution; GENETIQUE; Gravitropism; Indoleacetic Acids - metabolism; Indoleacetic Acids - pharmacology; Membrane Transport Proteins - chemistry; Molecular Sequence Data; Molecular Weight; Mutation; Phenotypes; Plant genetics; Plant growth regulators; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Plant roots; Plant Roots - growth & development; Plant Roots - metabolism; PLANTAS TRANSGENICAS; PLANTE TRANSGENIQUE; Plants; Pteridophyta, spermatophyta; RACINE; RAICES; Root growth; Roots (Botany); Sequence Alignment; Signal Transduction; Vegetals
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.273.5277.948

The plant hormone auxin regulates various development processes including root formation, vascular development, and gravitropism. Mutations within the AUX1 gene confer an auxin-resistant root growth phenotype and abolish root gravitropic curvature. Polypeptide sequence similarity to amino acid permeases suggests that AUX1 mediates the transport of an amino acid-like signaling molecule. Indole-3-acetic acid, the major form of auxin in higher plants, is structurally similar to tryptophan and is a likely substrate for the AUX1 gene product. The cloned AUX1 gene can restore the auxin-responsiveness of transgenic aux1 roots. Spatially, AUX1 is expressed in root apical tissues that regulate root gravitropic curvature