Figure 3. Functional recovery analysis for rec-AQP2 forms in oocytes.

Oocytes were injected with 0.5 ng mRNA coding for wt, V24A, D150E or R187C either in absence (−) or presence (+) of same amount of wt-AQP2 and incubated for 24 hours prior testing for water permeability (P_f). Activities are presented in % ± SD of wt-AQP2 with n = 8 per condition, and is typical of 6 assays. (A) Total activity. (B) Specific activity for single (control value subtracted from all (−) expressions), and double (wt-AQP2 value subtracted from all (+) expressions) expressing conditions. (C) Gain of function for each AQP2 variant calculated by subtracting specific P_f values determined in absence (−) to those determined in presence (+) of wt-AQP2. Western blots in panel B represent specific labeling (29 kDa) for each mutant either in absence (−) or presence (+) of GFP-wt-AQP2 (58 kDa, not seen in blot), for both total and plasma membranes. Asterisks indicate statistical significance from zero (p = 0.001).