Disruption of membrane cholesterol organization impairs the concerted activity of PIEZO1 channel clusters

Abstract

ABSTRACTThe human mechanosensitive ion channel PIEZO1 is gated by membrane tension and regulates essential biological processes such as vascular development and erythrocyte volume homeostasis. Currently, little is known about PIEZO1 plasma membrane localization and organization. Using a PIEZO1-GFP fusion protein, we investigated whether cholesterol enrichment or depletion by methyl-β-Cyclodextrin (MBCD) and disruption of membrane cholesterol organization by dynasore affects PIEZO1-GFP’s response to mechanical force. Electrophysiological recordings in the cell-attached configuration revealed that MBCD caused a rightward shift in the PIEZO1-GFP pressure-response curve, increased channel latency in response to mechanical stimuli and markedly slowed channel inactivation. The same effects were seen in native PIEZO1 in N2A cells. STORM super-resolution imaging revealed that, at the nano-scale, PIEZO1-GFP channels in the membrane associate as clusters sensitive to membrane manipulation. Both cluster distribution and diffusion rates were affected by treatment with MBCD (5 mM). Supplementation of poly-unsaturated fatty acids appeared to sensitize the PIEZO1-GFP response to applied pressure. Together, our results indicate that PIEZO1 function is directly dependent on the membrane mechanical properties and lateral organization of membrane cholesterol domains which coordinates the concerted activity of PIEZO1 channels.SUMMARYThe essential mammalian mechanosensitive channel PIEZO1 organizes in the plasma membrane into nanometric clusters which depend on the integrity of cholesterol domains to rapidly detect applied force and especially inactivate syncronously, the most commonly altered feature of PIEZO1 in pathology.