Fig. 1.

The transporters that might be found in the membranes of a halophyte cell (after Volkov, 2015a). The estimated concentration of Na⁺ is that of a mesophyll cell of Suaeda maritima and the pH values are taken from the literature: abbreviations enclosed by ovals are ion channels, and those within rectangles are transporters. Plasma membrane: KIRC, inward rectifying potassium channels; CNGC, cyclic-nucleotide gated ion channels; GluR, glutamate receptors; KORC, outward rectifying potassium channels; H⁺ATPase, plasma membrane proton pump; HAK, high affinity potassium transporter; CHXT, cation H⁺ exchange transporters; HKT, high affinity K⁺ transporters; C-Cl-CT, cation–chloride co-transporters; SOS1, sodium–proton antiporter. Tonoplast: V-H⁺ ATPase, tonoplast proton pump; V-H⁺ PPase, tonoplast pyrophosphatase; and NHX1, tonoplast sodium (cation)/proton antiporter.