Growth assays of S. cerevisiae strains expressing V. vinifera aquaporins under osmotic stress.

Hyperosmotic stress was exerted by osmo-equivalent concentration of either KCl or sorbitol. Yeast strain transformed with empty pUG35 plasmid was used as control (pUG35). Yeast suspensions were spotted in 10-fold dilution on solid YNB plates without or with 1.5 M KCl or 2.1 M sorbitol. Growth was recorded after two weeks at 28°C. Photographs shown are representative of three independent experiments with consistent results.