Constitutive boost of a K⁺ channel via inherent bilayer tension and a unique tension-dependent modality.

ABSTRACT: Molecular mechanisms underlying channel-membrane interplay have been extensively studied. Cholesterol, as a major component of the cell membrane, participates either in specific binding to channels or via modification of membrane physical features. Here, we examined the action of various sterols (cholesterol, epicholesterol, etc.) on a prototypical potassium channel (KcsA). Single-channel current recordings of the KcsA channel were performed in a water-in-oil droplet bilayer (contact bubble bilayer) with a mixed phospholipid composition (azolectin). Upon membrane perfusion of sterols, the activated gate at acidic pH closed immediately, irrespective of the sterol species. During perfusion, we found that the contacting bubbles changed their shapes, indicating alterations in membrane physical

SUBMITTER: Iwamoto M 

PROVIDER: S-EPMC6304998 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature