Inhibition of water permeability by mercury chloride (HgCl₂) in yeast strains expressing V. vinifera aquaporins.

(A) Inhibition of water permeability in yeast cells expressing functional aquaporin (VvTnTIP2;2) by HgCl₂. The green signal represents water permeability without HgCl₂ and the red signal shows the lower permeability when cells were incubated with 0.5 mM HgCl₂ for 15 minutes prior to osmotic shock. (B) Water permeability coefficients (P_f at 23°C) of VvTnPIP2;1, VvTnTIP1;1 and VvTnTIP2;2 were reduced by 0.5 mM HgCl₂. Data are mean ± SD of three independent experiments with at least five traces. The data were analyzed by t-test and asterisks above bars indicate statistically significant differences, where **p<0.01, ***p<0.001.