Figure 4.

Summary of whole-cell conductances observed in oocytes expressing various truncated versions of CFTR. All truncations induced enhanced baseline Cl⁻ conductance. When stimulated with IBMX and forskolin, only oocytes expressing the N-terminal half of CFTR including the R domain (E831X) responded with an increase of the whole-cell conductance. The numbers of experiments are shown in parentheses. ∗, Significant difference from control (P < 0.002). ^§, Significant difference from water-injected oocytes (P < 0.01).