Activation-pathway transitions in human voltage-gated proton channels revealed by a non-canonical fluorescent amino acid.

ABSTRACT: Voltage-dependent gating of the voltage-gated proton channels (H_V1) remains poorly understood, partly because of the difficulty of obtaining direct measurements of voltage sensor movement in the form of gating currents. To circumvent this problem, we have implemented patch-clamp fluorometry in combination with the incorporation of the fluorescent non-canonical amino acid Anap to monitor channel opening and movement of the S4 segment. Simultaneous recording of currents and fluorescence signals allows for direct correlation of these parameters and investigation of their dependence on voltage and the pH gradient (ΔpH). We present data that indicate that Anap incorporated in the S4 helix is quenched by an aromatic residue located in the S2 helix and that motion of the S4 relative to

SUBMITTER: Suarez-Delgado E 

PROVIDER: S-EPMC9925047 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature