The GATA transcription factors GLN3 and GAT1 link TOR to salt stress in Saccharomyces cerevisiae

One of the most recent functions assigned to the TOR signaling pathway in y east is the coordination of the transcription of genes involved in nutrient utilization. Here we show that transcription of ENA1, a gene encoding a li thium and sodium ion transporter essential for salt tolerance in yeast, is controlled by the TOR signaling pathway. First, ENA1 expression is strongly induced under TOR-inactivating conditions. Second, the absence of the TOR- controlled GATA transcription factors GLN3 and GAT1 results in reduced basa l and salt-induced expression of ENA1 Third, a gln3 gat1 mutant displays a pronounced sensitivity to high concentrations of lithium and sodium. Fourth , TOR1, similar to ENA1, is required for growth under saline stress conditi ons. In summary, our results suggest that TOR plays a role in the general r esponse to saline stress by regulating the transcription of ENA1 via GLN3 a nd GAT1.