Regulation of sulfate assimilation by nitrogen and sulfur nutrition in poplar trees

摘要: Plants cover their need for sulfur by taking up inorganic sulfate, reducing it to sulfide, and incorporating into the amino acid cysteine. In herbaceous plants pathway of assimilatory sulfate reduction is highly regulated availability nutrients nitrate. To investigate regulation assimilation in deciduous trees we used poplar hybrid Populus tremula × P. alba as a model. The enzymes are present several isoforms, except sulfite reductase γ-glutamylcysteine synthetase; genomic organization thus similar plants. mRNA level APS reductase, key enzyme pathway, was induced 3 days deficiency reduced nitrogen roots, whereas leaves affected only withdrawal nitrogen. When both were absent, levels did not differ from those control Four weeks affect growth plants, but content glutathione, most abundant low molecular thiol, compared Sulfur limitation resulted an increase ATP sulfurylase, probably adaptation mechanism efficiency pathway. Altogether, although distinct differences found, e.g. no effect on APR leaves, nutrient observed described