Piezo1 channels are essential mechanically activated ion channels in vertebrates. Their selective activation by the synthetic chemical activator Yoda1 opened new avenues to probe their gating mechanisms and develop novel pharmaceuticals. Yet, the nature and extent of Piezo1 functions modulated by this small molecule remain unclear. Here we close this gap by conducting a comprehensive biophysical investigation of the effects of Yoda1 on mouse Piezo1 in mammalian cells. Using calcium imaging, we first show that cysteine bridges known to inhibit mechanically evoked Piezo1 currents also inhibit activation by Yoda1, suggesting Yoda1 acts by energetically modulating mechanosensory domains. The presence of Yoda1 alters single-channel dwell times and macroscopic kinetics consistent with a dual and reciprocal energetic modulation of open and shut states. Critically, we further discovered that the electrophysiological effects of Yoda1 depend on membrane potential and temperature, two other Piezo1 modulators. This work illuminates a complex interplay between physical and chemical modulators of Piezo1 channels.
Keywords: Piezo1; Yoda1; mechanotransduction; membrane potential; temperature.