Portraits of a pressure sensor

Abstract

Near atomic-resolution structures have provided insights into the mechanisms by which the Piezo1 ion channel senses and responds to mechanical stimuli.

Keywords: biophysics; cryoEM; human; mechanosensitivity; mouse; neuroscience; piezo ion channels; somatosensation; structural biology; vascular system.

Figure 1.. Details of the Piezo1 ion channel.

(A) The schematic structure of Piezo1 viewed from above, showing the three 'propeller blades' surrounding a central pore. A single propeller blade is highlighted in blue. (B) A side view of the structure of Piezo1 as revealed by cryo-electron microscopy, with a single propeller blade highlighted in dark and medium blue: the interior of the cell is at the bottom of the figure. Each propeller blade contains at least six piezo-repeats, but only the three nearest to the central pore are shown (medium blue). Each propeller blade also includes a 'beam' domain (dark blue) that is parallel to the cell membrane, and a structure called the 'latch' (dark blue) that is in contact with the intracellular ends of the inner helices (dark grey) that form the central pore. Each propeller also contains a 'clasp' domain (medium blue): this domain interacts further from the pore, but its structure has not been determined yet. (C) When the cell is not submitted to pressure, Piezo1 bends the membrane to make a dome-like structure pointing inside the cell, and the channel is closed. When the membrane is stretched the complex flattens out, opening the channel.