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Updated: Apr 16, 2026

Measuring the Osmotic Water Permeability Coefficient Pf of Spherical Cells: Isolated Plant Protoplasts as an Example
Published on: October 8, 2014
[Optimal permeability of aquaporins: a question of shape?]
Simon Gravelle1, Laurent Joly1, François Detcheverry1
1Institut lumière matière, UMR5306 université Lyon 1-CNRS, université de Lyon, 3, boulevard du 11 novembre 1918, 69622 Villeurbanne, France.
Abstract:
Aquaporins are transmembrane proteins, ubiquitous in the human body. Inserted into the cell membranes, they play an important role in filtration, absorption and secretion of fluids. However, the excellent compromise between selectivity and permeability of aquaporins remains elusive. In this review, we focus on the hourglass shape of aquaporins, and we investigate its influence on water permeability, using numerical calculations and a simple theoretical model. We show that there is an optimum opening angle that maximizes the hydrodynamic permeability, and whose value is close to the angles observed in aquaporins.
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