Abstract
Molybdenum (Mo) is an essential trace element of many organisms including plants, and Mo deficiency and excess are agricultural problems. In plants, Mo cofactor (Moco) is an essential cofactor for several enzymes including nitrate reductase. Decrease of Moco amount under low Mo condition was reported, suggesting that Mo deficiency induce unusual nitrogen metabolism. Despite such importance, molecular mechanisms of Mo transport have not been understood. In the process of the analysis of an Arabidopsis thaliana mutant bor1-1, we noticed that Mo contents in leaves were several fold different between Col-0 and Ler. Genetic analysis indicated that the difference was determined by a single locus. The corresponding was identified as a putative membrane protein homologous to several known transporters. Activity of the membrane protein to transport Mo, phenotype of the T-DNA insertion mutants and expression patterns in plants will be presented.
