A theoretical model for calculating voltage sensitivity of ion channels and the application on Kv1.2 potassium
Huaiyu Yang1, Zhaobing Gao, Ping Li
1Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
Abstract:
Voltage sensing confers conversion of a change in membrane potential to signaling activities underlying the physiological processes. For an ion channel, voltage sensitivity is usually experimentally measured by fitting electrophysiological data to Boltzmann distributions. In our study, a two-state model of the ion channel and equilibrium statistical mechanics principle were used to test the hypothesis of empirically calculating the overall voltage sensitivity of an ion channel on the basis of its closed and open conformations, and determine the contribution of individual residues to the voltage sensing. We examined the theoretical paradigm by performing experimental measurements with Kv1.2 channel and a series of mutants. The correlation between the calculated values and the experimental values is at respective level, R(2) = 0.73. Our report therefore provides in silico prediction of key conformations and has identified additional residues critical for voltage sensing.
Related Concept Videos
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 types of...
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 types of...
The Role of Ion Channels in Neuronal Computation
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.
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.
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.
Electrochemical Gradient and Channel Proteins: An Overview
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...


