Fig. 6: SCAM confirms the roles of H229 and D570 in proton conductance.
From: The roles of two extracellular loops in proton sensing and permeation in human Otop1 proton channel
a Schematic showing the modification of MTSET on cysteine. b Gap-free recording showing the currents of WT and mutant Otop1 channels at pH 4 before and after 2-min treatment of 1 mM MTSET. Oocytes were clamped at −60 mV. Dashed lines indicate the current sizes before MTSET treatment. The cartoons on the left demonstrate the reaction of MTSET with the substituted cysteine residues. c The scatter plot and bar graph showing the effect of MTSET treatment on indicated WT and mutant Otop1 channels. Currents at pH 4 after 1 mM MTSET treatment for 2 min are compared with that before treatment. Data in the bar graphs are presented as mean ± SD. Effects on the mutants were compared to that on the WT with Student’s t-test (***P < 0.001, n.s.: no significance). The numbers of oocytes in each group are indicated in parentheses. d Gap-free recording showing that the application of DTT (50 mM) for 1 min can rescue the effect of MTSET treatment on the D570 mutant. Meanwhile, the WT channel was not affected by DTT treatment.
