Figure 4: Inactivation protects roNaV2 from modification.
(a) Two successive current traces from HEK 293 cells expressing roNaV2 measured with the pulse protocol shown in the top panel. For the first trace no light was on, for the second trace 470-nm light was on between the control and the test pulse as indicated by the blue bar. The interval between the first and the second pulse was about 5 s. (b) Relative change in non-inactivating current (ΔRI) from the experiment shown in (a) and successive sweeps as a function of real-time; white symbols refer to the control pulses, black symbols to the test pulses, blue lines connect consecutive control and test pulses. Episodes of 300-ms blue light exposure are indicated by the blue symbols at the top and manifest in strong increases of RI in the subsequent pulses. (c) Similar current recordings as in (a) but the blue-light pulse was given while the channel was kept in an inactivated (closed) state by holding the membrane voltage at −20 mV. (d) As in (b) for the data from (c).
