Modulation of Kv Channel Gating by Light-Controlled Membrane Thickness
Rohit Yadav1, Juergen Pfeffermann1, Nikolaus Goessweiner-Mohr1
1Institute of Biophysics, Johannes Kepler University Linz, 4040 Linz, Austria.
Biomolecules
|May 28, 2025
Summary
Membrane thickness directly controls voltage-gated potassium (Kv) channel activity. Light-induced membrane changes reversibly modulated KvAP channel function, demonstrating a link between membrane mechanics and voltage sensing.
Area of Science:
- Biophysics
- Molecular Biology
- Membrane Protein Dynamics
Background:
- Voltage-gated potassium (Kv) channels are crucial for neuronal electrical activity.
- Anionic lipids are known to influence Kv channel gating, but the precise mechanisms are unclear.
- Previous studies suggested a link between membrane thinning and Kv channel down states.
Purpose of the Study:
- To investigate the direct impact of membrane thickness on voltage-gated potassium channel function.
- To explore a novel, light-controlled method for modulating ion channel activity.
- To establish a mechanistic link between membrane mechanics and voltage-sensing domains.
Main Methods:
- Reconstitution of Aeropyrum pernix Kv channels (KvAP) into photoswitchable lipid bilayers.
- Utilizing blue and UV light to reversibly alter membrane thickness.
- Measuring KvAP channel activity in response to light-induced membrane property changes.
Main Results:
- Blue light illumination induced membrane thickening and increased KvAP channel activity.
- UV light exposure reversed these effects, decreasing membrane thickness and KvAP activity.
- Demonstrated a direct, reversible correlation between membrane thickness and Kv channel gating.
Conclusions:
- Membrane thickness directly influences voltage-gated potassium channel gating by modulating voltage sensor-lipid interactions.
- Light-activated membrane property modulation offers a non-genetic tool to control ion channel function.
- Findings provide insights into remote control of neuronal excitability via membrane mechanics.
Related Concept Videos
01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
4.8K
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
4.8K
01:12Mechanically-gated Ion Channels
8.1K
Mechanically-gated ion channels are proteins found in eukaryotic and prokaryotic cell membranes that open in response to mechanical stress. Tension, compression, swelling, and shear stress can alter the conformation of the protein, opening a transmembrane channel that allows the passage of ions for signal transmission. In eukaryotes, mechanically-gated channels are distributed in several regions like the neurons, lungs, skin, bladder, and heart, where they play critical roles in numerous...
8.1K
01:12Mechanically-gated Ion Channels
4.6K
4.6K
01:21G-Protein Gated Ion Channels
6.9K
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...
Sensory...
6.9K
01:26Voltage-gated Ion Channels
13.1K
Voltage-gated ion channels are transmembrane proteins that open and close in response to changes in the membrane potential. They are present on the membranes of all electrically excitable cells such as neurons, heart, and muscle cells.
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 types of...
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 types of...
13.1K
01:26Voltage-gated Ion Channels
6.4K
6.4K