Robust Stimulation of W1282X-CFTR Channel Activity by a Combination of Allosteric Modulators
Fig 2
W1282X-CFTR channels exhibit exceptionally low Pos in excised HEK-293T patches under control conditions and correspondingly slow activation time courses by 300 nM VX-770.
Activation conditions were identical to Fig 1. Holding potential was +60 mV throughout. Inset shows unitary currents under control activation conditions visualized at high gain. The indicated values for the control Po, opening rate/channel and closed time constant were calculated for this control record after estimating the total number of channels in the patch from the VX-770 stimulated current. These Po and opening rate values are maximal estimates (see Experimental Procedures). The macroscopic activation time course was fit to a single exponential with a time constant of 273s.