Boron-toxicity tolerance in barley arising from efflux transporter amplification.
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.
Sutton
Tim
T
Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Private Mail Bag 1, Glen Osmond, South Australia 5064, Australia. tim.sutton@acpfg.com.au
Baumann
Ute
U
Hayes
Julie
J
Collins
Nicholas C
NC
Shi
Bu-Jun
BJ
Schnurbusch
Thorsten
T
Hay
Alison
A
Mayo
Gwenda
G
Pallotta
Margaret
M
Tester
Mark
M
Langridge
Peter
P
D000595:Amino Acid Sequence; D001483:Base Sequence; D001692:Biological Transport; D001895:Boron / Q000378:metabolism / Q000633:toxicity*; D001896:Boron Compounds / Q000378:metabolism* / Q000633:toxicity*; D002874:Chromosome Mapping; D017343:Genes, Plant; D001467:Hordeum / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D037121:Plant Lectins / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D040641:Quantitative Trait Loci; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D014158:Transcription, Genetic
D001896:Boron Compounds; D026901:Membrane Transport Proteins; D037121:Plant Lectins; D010940:Plant Proteins; D001895:Boron