Related Experiment Video
Updated: Jun 9, 2025

Determination of the Relative Cell Surface and Total Expression of Recombinant Ion Channels Using Flow Cytometry
Published on: September 28, 2016
A Rich Conformational Palette Underlies Human CaV2.1-Channel Availability
Kaiqian Wang1, Michelle Nilsson1, Marina Angelini2
1Division of Cell and Neurobiology, Department of Biomedical and Clinical Sciences, Linköping University; SE-581 85 Linköping, Sweden.
Abstract:
Depolarization-evoked opening of CaV2.1 (P/Q-type) Ca2+-channels triggers neurotransmitter release, while voltage-dependent inactivation (VDI) limits channel availability to open, contributing to synaptic plasticity. The mechanism of CaV2.1 response to voltage is unclear. Using voltage-clamp fluorometry and kinetic modeling, we optically tracked and physically characterized the structural dynamics of the four CaV2.1 voltage-sensor domains (VSDs). VSD-I seems to directly drive opening and convert between two modes of function, associated with VDI. VSD-II is apparently voltage-insensitive. VSD-III and VSD-IV sense more negative voltages and undergo voltage-dependent conversion uncorrelated with VDI. Auxiliary -subunits regulate VSD-I-to-pore coupling and VSD conversion kinetics. CaV2.1 VSDs are differentially sensitive to voltage changes brief and long-lived. Specifically the voltage-dependent conformational changes of VSD-I are linked to synaptic release and plasticity.
More Related Videos
08:54Monitoring Leucine-Rich Repeat Containing 8 Channel (LRRC8/VRAC) Activity Using Sensitized-Emission Förster Resonance Energy Transfer (SE-FRET)
Published on: August 9, 2024
12:26Author Spotlight: Functional Site-Directed Fluorometry in Native Cells to Study Skeletal Muscle Excitability
Published on: June 2, 2023
Related Concept Videos
Ligand-gated Ion Channels
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that...
Voltage-gated Ion Channels
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several...
Non-gated Ion Channels
Compared to the gated ion channels, the non-gated channels, also known as leakage or passive channels, have no gating mechanism....
Mechanically-gated Ion Channels
Ligand-Gated Ion Channel Receptor: Gating Mechanism
Ion Channels
Ion channels are specialized integral membrane proteins on the plasma membrane that allow...