EIR1, a root-specific protein involved in auxin transport, is required for gravitropism in Arabidopsis thaliana.
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.
Luschnig
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Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142-1479 USA.
Gaxiola
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Grisafi
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Fink
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D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018744:DNA, Plant; D005030:Ethylenes / Q000378:metabolism; D015870:Gene Expression; D018522:Gravitropism / Q000502:physiology*; D006706:Homeostasis; D007210:Indoleacetic Acids / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D017386:Sequence Homology, Amino Acid
D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D018744:DNA, Plant; D005030:Ethylenes; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; D010940:Plant Proteins; C117013:AT5G57090 protein, Arabidopsis; C036216:ethylene