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Povstyan, O. V.

Publications and source records attributed to Povstyan, O. V..

2 recordsLinked to original sources

Computational reconstruction of the complete Piezo1 structure reveals a unique footprint and specific lipid interactions

Piezo1 is a critical mechanical sensor in many cells. It is activated by mechanical force thus allowing cells to sense the physical environment and respond to stress. Structural data have suggested that Piezo1 has a curved shape. Here, we use computational approaches to model, for the first time, the 3D structure of the full-length Piezo1 in an asymmetric membrane. A number of novel insights emerge: (i) Piezo1 creates a dome in the membrane with a trilobed topology that extends beyond the radius of the protein, (ii) Piezo1 changes the lipid environment in its vicinity via specific interactions with cholesterol and PIP2 molecules, (iii) changes in cholesterol concentration that change the membrane stiffness result in changes in the depth of the dome created by Piezo1, and iv) modelling of the N-terminal region that is missing from current structures modifies Piezo1 membrane footprint, suggesting the importance of this region in Piezo1 function.

biophysics↗

Cell adhesion molecule interaction with Piezo1 channels is a mechanism for sub cellular regulation of mechanical sensitivity

The discovery of Piezo1 channels as force sensors with roles in the endothelial response to fluid flow has appeared contradictory to earlier work suggesting mediation by a triad of cell adhesion molecules (CD31 and VE-cadherin) and vascular endothelial growth factor receptor 2 (VEGFR2). Here we propose an explanation. Stimulated emission depletion microscopy revealed physical proximity between Piezo1 and CD31 primarily at cell junctions. Forster resonance energy transfer measured by fluorescence lifetime imaging showed that the proteins approached to less than 10 nm. Substitution of a tyrosine residue at the distal C-terminus of CD31 prevented the interaction, suggesting intracellular association. The extracellular N-terminus also interacted, but exclusively at cell junctions. There was proximity between Piezo1 and VE-cadherin but not VEGFR2. Interaction with VE-cadherin was flow-dependent, consistent with additional recruitment after flow-sensing. CD31 suppressed mechanical sensitivity of Piezo1 channels and interacted with N-terminal Piezo1 propeller arms implicated in force sensing. The data suggest partnership between Piezo1 and adhesion molecules for sub cellular tuning of force response.

cell biology↗