Tellurite-resistance/Dicarboxylate Transporter (TDT) family includes SLAC1 (Slow Anion Channel-Associated 1)
SLAC1 (Slow Anion Channel-Associated 1) is a plasma membrane protein, preferentially expressed in guard cells, which encodes a distant homolog of fungal and bacterial dicarboxylate/malic acid transport proteins. It is essential for stomatal closure in response to carbon dioxide, abscisic acid, ozone, light/dark transitions, humidity change, calcium ions, hydrogen peroxide and nitric oxide. In the Arabidopsis genome, SLAC1 is part of a gene family with five members and encodes a membrane protein that has ten putative transmembrane domains flanked by large N- and C-terminal domains. Mutations in SLAC1 impair slow (S-type) anion channel currents that are activated by cytosolic calcium ions and abscisic acid, but do not affect rapid (R-type) anion channel currents or calcium ion channel function.
Comment:Mutational and structural studies in Haemophilus influenzae TehA (HiTehA) show that this residue plays a crucial role in gating of the anion channel
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