Extended Data Fig. 5: Representative whole-cell current recordings and I–V relationships of WT TRPM5 and mutants of the TPPO binding site in response to extracellular 100 μM TPPO.
From: A single allosteric site merges activation, modulation and inhibition in TRPM5
a–d, Raw current traces (left) and corresponding I–V plots (right) obtained from cells expressing R998A (a), F730A (b), I838A (c), and H837A (d). Currents were evoked using a voltage-ramp protocol from –100 mV to +100 mV, with 0.3 μM free intracellular Ca2+ in the pipette solution. 100 μM TPPO (red) was applied extracellularly via bath perfusion. I–V curves were generated from the current responses to the voltage ramp under bath (black) and TPPO (red) conditions. e, Representative time-course recordings of whole-cell TRPM5 currents measured at +100 mV and –100 mV from WT, R998A, F730A, H837A, and I838A. Currents were recorded with 0.3 μM free intracellular Ca2+, and 100 μM TPPO was applied extracellularly at the time indicated by the red bar.
