Boron-toxicity tolerance in barley arising from efflux transporter amplification

Science. 2007 Nov 30;318(5855):1446-9. doi: 10.1126/science.1146853.

Abstract

Both limiting and toxic soil concentrations of the essential micronutrient boron represent major limitations to crop production worldwide. We identified Bot1, a BOR1 ortholog, as the gene responsible for the superior boron-toxicity tolerance of the Algerian barley landrace Sahara 3771 (Sahara). Bot1 was located at the tolerance locus by high-resolution mapping. Compared to intolerant genotypes, Sahara contains about four times as many Bot1 gene copies, produces substantially more Bot1 transcript, and encodes a Bot1 protein with a higher capacity to provide tolerance in yeast. Bot1 transcript levels identified in barley tissues are consistent with a role in limiting the net entry of boron into the root and in the disposal of boron from leaves via hydathode guttation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Biological Transport
  • Boron / metabolism
  • Boron / toxicity*
  • Boron Compounds / metabolism*
  • Boron Compounds / toxicity*
  • Chromosome Mapping
  • Genes, Plant*
  • Hordeum / drug effects*
  • Hordeum / genetics*
  • Hordeum / metabolism
  • Membrane Transport Proteins / chemistry
  • Membrane Transport Proteins / genetics*
  • Membrane Transport Proteins / metabolism
  • Molecular Sequence Data
  • Plant Lectins / genetics
  • Plant Lectins / metabolism
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plant Roots / genetics
  • Plant Roots / metabolism
  • Quantitative Trait Loci
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism
  • Transcription, Genetic

Substances

  • Boron Compounds
  • Membrane Transport Proteins
  • Plant Lectins
  • Plant Proteins
  • Boron

Associated data

  • GENBANK/EF660435