Figure 3.

Reduced Water Loss and Stomatal Aperture in alix-1 Mutants.

(A) Kinetics of the loss of fresh weight in 15-day-old seedlings of wild-type (Col-0), complemented line GFP-ALIX/alix-1 (labeled as GFP-ALIX), oeHA-PYL4 (HA-PYL4) and alix-1 genotypes. The cra1 and hab1-1 abi1-2 mutants were used as ABA insensitive and hypersensitive controls, respectively. Plants were exposed for 40 min to the drying environment of a laminar flow hood. Values shown are averages ±se from three replicates (n = 15 in each replicate).

(B) IR imaging was used to analyze foliar temperature in wild-type (Col-0), complemented line GFP-ALIX/alix-1, and alix-1 plants. The ost2-2 mutant, which displays incompletely closed stomata, was used as a control. Correspondence between false colors and temperatures (degrees Celsius) in IR images is shown.

(C) Kinetics of stomatal aperture in response to light in leaves of wild-type (Col-0), GFP-ALIX/alix-1, and alix-1 plants. Values shown are averages ±se from three replicates (n = 70 in each replicate).

(D) Confocal imaging was used to visualize vacuolar morphology in guard cells of wild-type (WT, Col-0) and alix-1 plants expressing the tonoplast marker YFP-VAMP711. Plants were grown under short days for 21 d before leaves were collected. Bars = 10 and 5 µm, respectively.

(E) Stomatal aperture measurements in response to FC in dark- and light-treated leaves of wild-type (Col-0), GFP-ALIX/alix-1, and alix-1 plants. Values shown are averages ±se from three replicates (n = 70 in each replicate). *p < 0.05; **p < 0.01 (Student’s t test) with respect to the wild type in the same experimental conditions.