Panel A shows a line graph for 8A 8C(EL1 plus TM2), with time in minutes on the x-axis and relative current on the y-axis. Open circles represent positive 100 millivolts, and open triangles represent negative 100 millivolts. Panel B shows a line graph for 8A 8C(EL1 plus TM2) M139L, with the same axes and voltage conditions. Panel C shows a bar graph of percentage inhibition at positive 100 millivolts and negative 100 millivolts for 8A 8C(EL1 plus TM2), I133L, M139L, V137I, and L140A. Individual data points and error bars are shown. Double asterisks indicate P equals 0.0038, and four asterisks indicate P is less than 0.0001. Panel D shows a line graph for 8A 8C(EL1), comparing relative current at positive 100 millivolts and negative 100 millivolts over time. Panel E shows a line graph for 8A 8C(EL1) L139M under the same voltage conditions. Panel F shows a line graph for 8A, comparing relative current at positive 100 millivolts and negative 100 millivolts over time. Panel G shows a line graph for 8A L137M under the same voltage conditions. The x-axis of the line graphs represents time in minutes, and the y-axis represents relative current. Error bars are shown around the plotted measurements.
Analysis of chimera TM2 mutations on DCPIB sensitivity. (A and B) Time course of 10 μM DCPIB-induced inhibition of 8A-8C(EL1+TM2) (n = 4) and 8A-8C(EL1+TM2)-M139L (n = 5) currents. (C) Effects of single point mutations in TM2 on DCPIB inhibition (8A-8C(EL1+TM2) n = 4, I133L n = 7, V137I n = 5, M139L n = 5, L140A n = 5). (D–G) Time course of 10 μM DCPIB-induced inhibition of 8A-8C(EL1) (n = 4) (D and E) and 8A-8C(EL1)-L139M (n = 5) currents (F and G) Time course of 10 μM DCPIB-induced inhibition of 8A (n = 4) and 8A-L137M (n = 6) currents. All cells were exposed to a hypotonic buffer to activate the current. After full activation, 10 μM DCPIB was continuously applied until a new steady state was reached (3–4 min). Bars indicate the presence of 10 μM DCPIB in the bath solution. Data are means ± SEM. **P = 0.0038; ****P < 0.0001.