Figure 4.

Time course of TWCA1 decrease in response to increased CO₂ concentration. Cultures were preadapted to 100 μatm CO₂. At t = 0, experimental cultures were shifted to 750 μatm CO₂ and samples were withdrawn at the times indicated. Relative amounts of TWCA1 were determined by western analysis and phosphorimaging. All values were normalized to that of the initial timepoint (t = 0). The graph represents the average of two separate experiments. ●, 100 μatm CO₂; ♦, 750 μatm CO₂.