Related Experiment Video
Updated: Jul 7, 2026
12:26
Functional Site-Directed Fluorometry in Native Cells to Study Skeletal Muscle Excitability
Published on: June 2, 2023
A common pathway for charge transport through voltage-sensing domains
Baron Chanda1, Francisco Bezanilla
1Department of Physiology, University of Wisconsin, Madison, WI 53706, USA.
Neuron
|February 8, 2008
Summary
Charged residues move within voltage-gated ion channels, enabling voltage sensing. This pathway can be altered to transport protons, suggesting evolution utilized it for proton channels.
Area of Science:
- Molecular Biology
- Biophysics
- Structural Biology
Background:
- Voltage-gated ion channels sense changes in transmembrane potential via charged residue movement.
- Evidence suggests these gating charges traverse a defined permeation pathway.
- This pathway's plasticity allows for potential cation transport, including protons.
Purpose of the Study:
- To explore the implications of recent proton channel discoveries on voltage-sensing mechanisms.
- To discuss how evolution may have repurposed ion channel gating pathways for proton transport.
- To analyze the mechanisms of charge and ion transport within voltage-sensing domains.
Main Methods:
- Review and synthesis of existing studies on voltage-gated ion channel gating mechanisms.
- Comparative analysis of voltage-sensing domains and newly discovered proton channels.
- Theoretical discussion on charge and ion permeation pathways.
Main Results:
- Voltage-sensing domains possess a conserved gating pathway capable of ion transport.
- Proton channels share sequence homology with voltage-sensing domains, indicating a shared evolutionary origin.
- The gating pathway is a versatile structure adaptable for different ion permeation.
Conclusions:
- Evolution has likely exploited the charge movement pathway in voltage-sensing domains to create proton channels.
- Understanding these pathways is crucial for elucidating voltage-dependent ion and charge transport.
- The findings provide insights into the functional adaptability of voltage-sensing domains.
More Related Videos
11:42Reconstitution of a Transmembrane Protein, the Voltage-gated Ion Channel, KvAP, into Giant Unilamellar Vesicles for Microscopy and Patch Clamp Studies
Published on: January 22, 2015
13:56Modeling Biological Membranes with Circuit Boards and Measuring Electrical Signals in Axons: Student Laboratory Exercises
Published on: January 18, 2011
Related Concept Videos
01:26Voltage-gated Ion Channels
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...
01:26Voltage-gated Ion Channels
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...
01:21Electrochemical Gradient and Channel Proteins: An Overview
An electrochemical gradient is a fundamental concept in biology and chemistry. It regulates the movement of ions across cell membranes. This movement is influenced by two factors:
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
01:12Mechanically-gated Ion Channels
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...
01:12Mechanically-gated Ion Channels
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...
01:19The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.