<scp>NO₃</scp>⁻, <scp>PO₄³</scp>⁻ and <scp>SO₄²</scp>⁻ deprivation reduced <scp>LKT1</scp>‐mediated low‐affinity K⁺ uptake and <scp>SKOR</scp>‐mediated K⁺ translocation in tomato and Arabidopsis plants

Abstract

Regulation of essential macronutrients acquisition by plants in response to their availability is a key process for plant adaptation to changing environments. Here we show in tomato and Arabidopsis plants that when they are subjected to NO₃^- , PO₄³^- and SO₄²^- deprivation, low-affinity K⁺ uptake and K⁺ translocation to the shoot are reduced. In parallel, these nutritional deficiencies produce reductions in the messenger levels of the genes encoding the main systems for low-affinity K⁺ uptake and K⁺ translocation, i.e. AKT1 and SKOR in Arabidopsis and LKT1 and the tomato homolog of SKOR, SlSKOR in tomato, respectively. The results suggest that the shortage of one nutrient produces a general downregulation of the acquisition of other nutrients. In the case of K⁺ nutrient, one of the mechanisms for such a response resides in the transcriptional repression of the genes encoding the systems for K⁺ uptake and translocation.