Fig. 1
Rectification and voltage modulation of pressure-mediated PIEZO1 currents. a Left: example traces of currents elicited at a constant saturating pressure (70 mmHg) and at increasing voltages (in 20 mV steps from −100 to 100 mV) in symmetrical Na+ from excised outside-out patches overexpressing mPIEZO1 in N2a cells. Right: peak currents are plotted against voltage to show an I/V relationship. Note the outward rectifying behavior. b Left: single channel openings were recorded at negative and positive voltages to obtain the slope-conductance values. Right: linear regressions from individual patches were averaged and pooled. Inward slope conductance was significantly higher than outward slope conductance (41.3 ± 0.9 pS and 27.1 ± 1.2 pS, respectively, three cells. Student’s t-test P = 0.0006, dF = 4). c Example trace of instantaneous currents recorded upon switching voltage from +60 to −60 mV during the application of a 70 mmHg pressure stimulus (rectification index 1.13 ± 0.06 (n = 8)). Capacitance currents were digitally subtracted. d Current responses to a pressure stimulation of 70 mmHg during 300 ms voltage steps ranging from 0 to 150 mV, followed by a repolarization step to −60 mV to obtain tail currents. The inset shows an expanded example of tail currents at −60 mV originated from a pre-stimulation step at 80 (blue) and 140 mV (red) in the presence of 70 mmHg of pressure. e Tail currents from individual cells were normalized to their maximum and fitted to Boltzmann relationship (V50 = 91.9 ± 3.2 mV, slope 22.2 ± 0.9, 12 cells). Pooled data are shown as mean ± SEM
