Figure 2.

NLC measurements for prestin and prestin-based constructs. A–D, schematic diagrams of WT prestin (WT-A5) (A) and prestin-based constructs (A5-L₁ (B), A5-L₂ (C), and A5-L₁/L₂ (D)) along with their representative NLCs. The parts of prestin and pendrin are indicated by magenta and dark blue, respectively, in the schematic diagrams. The magnitudes of NLCs (C_m − C_lin) are corrected for cell size (C_lin) because larger cells tend to express greater amounts of prestin in their cell membranes (NLC_sp ≡ (C_m − C_lin)/C_lin). Different colors indicate individual recordings. A two-state Boltzmann model (see “Experimental procedures”) was used to interpret the NLC data (solid lines). E, the V_pk values (mean ± S.D.) are as follows: WT-A5, −91 ± 24 mV (n = 9); A5-L₁, −132 ± 31 mV (n = 13); A5-L₂, −169 ± 26 mV (n = 9); A5-L₁/L₂, −170 ± 24 mV (n = 9). The asterisks indicate the degree of statistical significance (**, p < 0.01; ****, p < 0.0001). Error bars represent S.D. ns, not significant. F, the α values (mean ± S.D.) are as follows: WT-A5, 0.031 ± 0.006 mV⁻¹ (n = 9); A5-L₁, 0.026 ± 0.007 mV⁻¹ (n = 13); A5-L₂, 0.025 ± 0.005 mV⁻¹ (n = 9); A5-L₁/L₂, 0.026 ± 0.005 mV⁻¹ (n = 9). Error bars represent S.D.