EIR1, a root-specific protein involved in auxin transport, is required for gravitropism in Arabidopsis thaliana

• Published in: Genes & development Vol. 12; no. 14; pp. 2175 - 2187
• Main Authors: Luschnig, C, Gaxiola, R A, Grisafi, P, Fink, G R
• Format: Journal Article
• Language: English
• Published: United States Cold Spring Harbor Laboratory Press 15-07-1998
• Subjects: Amino Acid Sequence; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins; Bacterial Proteins - genetics; Base Sequence; Biological Transport; Carrier Proteins - genetics; Carrier Proteins - physiology; Cloning, Molecular; Conserved Sequence; DNA, Plant; Ethylenes - metabolism; Gene Expression; Gravitropism - physiology; Homeostasis; Indoleacetic Acids - metabolism; Membrane Transport Proteins; Molecular Sequence Data; Phenotype; Plant Proteins - genetics; Plant Proteins - physiology; Plant Roots - growth & development; Plant Roots - metabolism; Research Paper; Saccharomyces cerevisiae; Sequence Homology, Amino Acid
• ISSN: 0890-9369; 1549-5477
• DOI: 10.1101/gad.12.14.2175

The EIR1 gene of Arabidopsis is a member of a family of plant genes with similarities to bacterial membrane transporters. This gene is expressed only in the root, which is consistent with the phenotypes of the eir1 mutants-the roots are agravitropic and have a reduced sensitivity to ethylene. The roots of eir1 mutants are also insensitive to the excess auxin produced by alf1-1 and fail to induce an auxin-inducible gene in the expansion zone. Although they fail to respond to internally generated auxin, they respond normally to externally applied auxin. Expression of the EIR1 gene in Saccharomyces cerevisiae confers resistance to fluorinated indolic compounds. Taken together, these data suggest that the EIR1 protein has a root-specific role in the transport of auxin.