Loss of an MDR transporter in compact stalks of maize br2 and sorghum dw3 mutants

Science. 2003 Oct 3;302(5642):81-4. doi: 10.1126/science.1086072.

Abstract

Agriculturally advantageous reduction in plant height is usually achieved by blocking the action or production of gibberellins. Here, we describe a different dwarfing mechanism found in maize brachytic2 (br2) mutants characterized by compact lower stalk internodes. The height reduction in these plants results from the loss of a P-glycoprotein that modulates polar auxin transport in the maize stalk. The sorghum ortholog of br2 is dwarf3 (dw3), an unstable mutant of long-standing commercial interest and concern. A direct duplication within the dw3 gene is responsible for its mutant nature and also for its instability, because it facilitates unequal crossing-over at the locus.

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / chemistry
  • ATP Binding Cassette Transporter, Subfamily B / genetics*
  • ATP Binding Cassette Transporter, Subfamily B / metabolism
  • Alleles
  • Amino Acid Sequence
  • Base Sequence
  • Biological Transport
  • Cloning, Molecular
  • Crossing Over, Genetic
  • Gene Duplication
  • Genes, Plant*
  • Genes, Recessive
  • Indoleacetic Acids / metabolism*
  • Light
  • Molecular Sequence Data
  • Mutation
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Stems / cytology
  • Plant Stems / metabolism
  • Poaceae / cytology
  • Poaceae / genetics
  • Poaceae / growth & development
  • Poaceae / metabolism*
  • Recombination, Genetic
  • Zea mays / cytology
  • Zea mays / genetics
  • Zea mays / growth & development
  • Zea mays / metabolism*

Substances

  • ATP Binding Cassette Transporter, Subfamily B
  • Indoleacetic Acids
  • Plant Proteins
  • indoleacetic acid