Figure 2
From: Structural changes in the cytoplasmic pore of the Kir1.1 channel during pHi-gating probed by FRET
pH i -gating of Kir1.1 channels. A. Currents were recorded at pHi 8.0 and 6.0 in an inside-out oocyte patch expressing ECFP-Kir1.1-EYFP. Currents were recorded by holding the membrane potential at -80 mV and stepping to +50 mV for 50 ms every 1 Hz. B. Normalized current-pHi relationship. Currents were normalized to those recorded at pH 8.0 for the wild-type Kir1.1 and ECFP-Kir1.1-EYFP construct and to those recorded at pH 10.0 for the S219R mutant and ECFP-S219R-EYFP construct. The smooth curves are the best fit of the data to the Hill equation: 1/{1 + [H+]/Kd]n}. n = 3 – 10. C. Currents were recorded at pHi 10.0 and 7.4 in an inside-out oocyte patch expressing ECFP-S219R-EYFP using the same protocol as in A. C-Kir1.1-Y and C-S219R-Y stand for ECFP-Kir1.1-EYFP and ECFP-S219R-EYFP, respectively.