Figure 2.

Schematic diagram showing Na⁺ fluxes mediated by SlSOS1 within the plant. The main action of SlSO1 is extruding Na⁺ out the root and the partitioning of Na⁺ in plant organs. Suppression of SlSOS1 causes a root-to-leaf gradient of Na⁺ distribution together with a reduced ability to accumulate Na⁺ in the stem. the transport function of the SOS1 and HKt systems may be coordinated to achieve Na⁺ and K⁺ homeostasis.