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Barnoud, J.

Publications and source records attributed to Barnoud, J..

2 recordsLinked to original sources

Piezo1 Induces Local Curvature in a Mammalian Membrane and Forms Specific Protein-Lipid Interactions

Touch, hearing, and blood pressure control require mechanically-gated ion channels that convert mechanical stimuli into electrical currents. Piezo1 and Piezo2 were recently identified as essential eukaryotic mechanically-gated ion channels, yet how they respond to physical forces remains poorly understood. Here we use a multi-disciplinary approach to interrogate the interaction of Piezo1 with its lipid environment. We show that individual Piezo1 channels induce significant local curvature in the membrane that is magnified in a cooperative manner to generate larger curved Piezo1 pits. Curvature decreases under lateral membrane tension, consistent with a hypothesis that force detection can involve sensing changes to local curvature. The protein alters its local membrane composition, enriching specific lipids and forming essential binding sites for phosphoinositides and cholesterol that are functionally relevant and often related to Piezo1-mediated pathologies. Finally, we show that Piezo1 alters the expression of lipid-regulating proteins and modifies the cellular lipidome. In short, we find that lipids influence Piezo1 activity and Piezo1 influences the local morphology and composition of the bilayer as well as the cellular lipidome.

biophysics↗

PBxplore: A Tool To Analyze Local Protein Structure And Deformability With Protein Blocks

Proteins are highly dynamic macromolecules. A classical way to analyze their inner flexibility is to perform molecular dynamics simulations. In this context, we present the advantage to use small structural prototypes, namely the Protein Blocks (PBs). PBs give a good approximation of the local structure of the protein backbone. More importantly, by reducing the conformational complexity of protein structures, they allow analyzes of local protein deformability which cannot be done with other methods and had been used efficiently in different applications. PBxplore is a suite of tools to analyze the dynamics and deformability of protein structures using PBs. It is able to process large amount of data such as those produced by molecular dynamics simulations. It produces various outputs with text and graphics, such as frequencies, entropy and information logo. PBxplore is available at https://github.com/pierrepo/PBxplore and is released under the open-source MIT license.

bioinformatics↗