Fig. 4.
RPR-induced enhancement of tail current integral at −70 mV is directly proportional to the number of WT subunits contained within a concatenated hERG1 tetramer. (A) Representative current traces for indicated LAn/WT4-n tetrameric hERG1 channels, recorded before and after treatment of oocyte with 30 µM RPR. Channels were activated with 4-second pulse to +20 mV, and tail currents were elicited at a Vret of −70 mV. (B) Bar graphs showing that the fold increase in ∫Itail induced by indicated concentration of RPR is increased (P < 0.0001, one-way analysis of variance) as a function of the number of WT subunits contained in a concatenated tetramer (n = 4–9). (C) Data for 50 µM RPR replotted and analyzed by linear regression (red line; y = 9.87x − 1.93; R2 = 0.97).