Effects of MTSET on a single cysless/M348C channel. (A) Single-channel traces in the presence of 2 mM ATP before (left top trace) and after MTSET modification (left middle trace, blue), and after DTT treatment (left bottom trace) in the same patch. Corresponding all-point histograms (gray bars) and their Gaussian fits (black and blue lines) were plot on the right. (B) Gating parameters of the cysless/M348C channel before (black) and after (blue) modification, as extracted from the traces in A. Those of the cysless/WT (gray) in the presence of 2 mM ATP are also included for comparison (traces not depicted). n = 5 for cysless/M348C. n = 6 for cysless/WT. (C) Single-channel amplitude of the cysless/M348C channel before and after modification in the same patch. Star indicates significant difference as determined by Student’s paired t test; n = 5.