A lever-like transduction pathway for long-distance chemical- and mechano-gating of the mechanosensitive Piezo1 channel

Abstract

Piezo1 represents a prototype of eukaryotic mechanotransduction channels. The full-length 2547-residue mouse Piezo1 possesses a unique 38-transmembrane-helix (TM) topology and is organized into a three-bladed, propeller-shaped architecture, comprising a central ion-conducting pore, three peripheral blade-like structures, and three 90-Å-long intracellular beam-resembling structures that bridge the blades to the pore. However, how mechanical force and chemicals activate the gigantic Piezo1 machinery remains elusive. Here we identify a novel set of Piezo1 chemical activators, termed Jedi, which activates Piezo1 through the extracellular side of the blade instead of the C-terminal extracellular domain of the pore, indicating long-range allosteric gating. Remarkably, Jedi-induced activation of Piezo1 requires the key mechanotransduction components, including the two extracellular loops in the distal blade and the two leucine residues in the proximal end of the beam. Thus, Piezo1 employs the peripheral blade-beam-constituted lever-like apparatus as a designated transduction pathway for long-distance mechano- and chemical-gating of the pore.

Tethering Piezo channels to the actin cytoskeleton for mechanogating via the E-cadherin-β-catenin mechanotransduction complex

“…On the basis of the identification of the transmembrane gate located in the inner helix (IH) and the cytosolic lateral plug gates that physically block the three lateral ion-conducting portals (Geng et al, 2020), we have proposed that Piezo channels might utilize a dual-gating mechanism, in which the transmembrane gate is dominantly controlled by the top extracellular cap , while the lateral plug gates are controlled by the peripheral blade-beam apparatus via a plug-and-latch mechanism (Geng et al, 2020;Wang et al, 2019;Wang et al, 2018;Zhao et al, 2018a;Zhao et al, 2018b) (Figure 7A, B). The cap domain is embedded in the center of the nano-bowl shaped by the curved Piezo1-membrane system and sits right on the top of the transmembrane pore of Piezo1 (Fig.…”

“…Structural analysis reveals large conformational changes of the highly curved blades, which might be converted to the cytosolic lateral plug gates via a lever-like motion of the featured beam structure (Fig. 7A, B) (Geng et al, 2020;Wang et al, 2019;Wang et al, 2018;Zhao et al, 2018a). Using the probe of an atomic force microscope to apply force to the Piezo1 channel reconstituted in lipid bilayers, Lin et al have elegantly demonstrated that the highly curved blade can undergo reversible flattening at biologically relevant pressures (Lin et al, 2019).…”

“…Furthermore, we have identified a serial of key mechanotransduction sites along the blade-beam-lateral plug gate (Geng et al, 2020;Wang et al, 2018;Zhao et al, 2018a), which might constitute an intramolecular mechanotransduction pathway for converting long-range conformational changes from the distal blades to the cytosolic lateral plug gates ( Fig. 7B) (Geng et al, 2020;Wang et al, 2018;Xiao, 2019;Zhao et al, 2018a).…”

“…HEK293T cells grown on 8-mm round glass coverslips coated with poly-D-lysine and placed in 48-well plates were transfected with either mRuby-Piezo1 alone or together with Flag-E-cadherin-ires-GFP, and then were subjected to Fura-2 Ca 2+ imaging 36 h post transfection according to the previously described protocol (Wang et al, 2018). The confluent cells were washed with buffer containing 1 × HBSS (with1.3 mM Ca 2+ ) and 10 mM HEPES (pH 7.2 with NaOH), then incubated with 2.5 The compound solutions were perfused into the chamber and cells via a multichannel perfusion system (MPS-2, World Precision Instruments).…”

Piezo1 channel activates ADAM10 sheddase to regulate Notch1 and gene expression

“…Therefore, we speculated about a potential relationship between Piezo1 and Notch1, using endothelial cells to investigate this idea because both proteins are prominent in these cells and have established functional significance in them 1,[8][9][10]12,19 . Because mechanical force can affect numerous mechanisms, we explored the relationship by specifically activating Piezo1 channels with a synthetic small-molecule agonist (Yoda1) that acts directly to enhance force sensitivity [21][22][23][24] . Because there is inherent force in cell membranes and force arises through cell-cell and cell-substrate contact, Yoda1 can be used to activate the channels in endothelial cells without applying an exogenous force 24 that might otherwise complicate the analysis by concurrently stimulating parallel mechanisms.…”