A role for flavin monooxygenase-like enzymes in auxin biosynthesis

Science. 2001 Jan 12;291(5502):306-9. doi: 10.1126/science.291.5502.306.

Abstract

Although auxin is known to regulate many processes in plant development and has been studied for over a century, the mechanisms whereby plants produce it have remained elusive. Here we report the characterization of a dominant Arabidopsis mutant, yucca, which contains elevated levels of free auxin. YUCCA encodes a flavin monooxygenase-like enzyme and belongs to a family that includes at least nine other homologous Arabidopsis genes, a subset of which appears to have redundant functions. Results from tryptophan analog feeding experiments and biochemical assays indicate that YUCCA catalyzes hydroxylation of the amino group of tryptamine, a rate-limiting step in tryptophan-dependent auxin biosynthesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Amino Acid Sequence
  • Arabidopsis / anatomy & histology
  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins*
  • Catalysis
  • Cloning, Molecular
  • Genes, Plant
  • Indoleacetic Acids / biosynthesis*
  • Indoleacetic Acids / metabolism*
  • Molecular Sequence Data
  • Mutation
  • Oxidation-Reduction
  • Oxygenases / chemistry
  • Oxygenases / metabolism*
  • Phenotype
  • Plant Roots / growth & development
  • Plants, Toxic
  • Tobacco / metabolism
  • Tryptamines / metabolism
  • Tryptophan / analogs & derivatives*
  • Tryptophan / metabolism
  • Tryptophan / pharmacology

Substances

  • Arabidopsis Proteins
  • Indoleacetic Acids
  • Tryptamines
  • 5-methyltryptophan
  • tryptamine
  • Tryptophan
  • Oxygenases
  • YUC protein, Arabidopsis