The Water Permeability and Pore Entrance Structure of Aquaporin-4 Depend on Lipid Bilayer Thickness.

ABSTRACT: Aquaporin-4 (AQP4), the primary water channel in glial cells of the mammalian brain, plays a critical role in water transport in the central nervous system. Previous experiments have shown that the water permeability of AQP4 depends on the cholesterol content in the lipid bilayer, but it was not clear whether changes in permeability were due to direct cholesterol-AQP4 interactions or to indirect effects caused by cholesterol-induced changes in bilayer elasticity or bilayer thickness. To determine the effects resulting only from bilayer thickness, here we use a combination of experiments and simulations to analyze AQP4 in cholesterol-free phospholipid bilayers with similar elastic properties but different hydrocarbon core thicknesses previously determined by x-ray diffraction. The channel (

SUBMITTER: Tong J 

PROVIDER: S-EPMC4944661 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature