Figure 5.

Kinetics of changes in the cell volume of Xenopus oocytes expressing rubber aquaporin. A negative control (NC) oocyte injected with water, a positive control oocyte injected with HvPIP2;4, and tested rubber aquaporin-expressing oocytes were transferred into a hypotonic solution at time 0 and monitored every 20 s for up to 180 s or until they burst in the case of HbPIP2;1- or HvPIP2;4-expressing oocytes. For testing effects of the aquaporin inhibitor, oocytes were injected with the complementary RNA encoding the rubber HbPIP2;1 aquaporin and incubated for 10 min in the presence of 1 mm HgCl₂ before analysis of swelling.