Stretch-activated ion channel
Encyclopedia
Stretch-activated or stretch-gated ion channels are ion channels which open their pores in response to mechanical deformation of a neuron
's plasma membrane. Stretch-activated channels were first observed in chick skeletal muscles by Falguni Guharay and Frederick Sachs in 1983 and the results were published in 1984. Since then strech-activated channels have been found in cells from bacteria to human as well as plants.
s to which they are permeable to flow down their electrochemical gradient
s into or out of the cell
, causing a change in membrane potential
.
This can also be referred to as the Stress-activated gate because the gate (protein receptor) responds to pressure or stress.
from a mechanical stimulus, for example by the mechanoreceptors in an animal's vibrissae (whiskers).
A possible role in myoblast
development has been described.
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
's plasma membrane. Stretch-activated channels were first observed in chick skeletal muscles by Falguni Guharay and Frederick Sachs in 1983 and the results were published in 1984. Since then strech-activated channels have been found in cells from bacteria to human as well as plants.
Mechanism
One of the three main types of ionotropic receptors or channel-linked receptor, which open by transmitting physical forces of stretch or pressure to the channels, causing them to undergo a conformational change to allow ions to pass through. The channels may also be pulled open due to tension on the membrane itself. Opening the channels allows ionIon
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
s to which they are permeable to flow down their electrochemical gradient
Electrochemical gradient
An electrochemical gradient is a spatial variation of both electrical potential and chemical concentration across a membrane; that is, a combination of the membrane potential and the pH gradient...
s into or out of the cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
, causing a change in membrane potential
Membrane potential
Membrane potential is the difference in electrical potential between the interior and exterior of a biological cell. All animal cells are surrounded by a plasma membrane composed of a lipid bilayer with a variety of types of proteins embedded in it...
.
This can also be referred to as the Stress-activated gate because the gate (protein receptor) responds to pressure or stress.
Functions
Such channels are of use in the initial formation of an action potentialAction potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
from a mechanical stimulus, for example by the mechanoreceptors in an animal's vibrissae (whiskers).
A possible role in myoblast
Myoblast
A myoblast is a type of embryonic progenitor cell that gives rise to muscle cells .The muscle cells can be skeletal muscle, smooth muscle, and cardiac muscle....
development has been described.
See also
- Mechanosensitive ion channelMechanosensitive ion channelMechanosensitive channels are found in a number of tissues and organisms and are thought to be the sensors for a number of systems including the senses of touch, hearing and balance, as well as participating in cardiovascular regulation and osmotic homeostasis...
- Large-conductance mechanosensitive channelLarge-conductance mechanosensitive channelMechanosensitive ion channels play a critical role in transducing physical stresses at the cell membrane into an electrochemical response.MscL forms a channel organized as a homopentamer, with each subunit containing two transmembrane α-helices...
- Voltage-gated ion channelVoltage-gated ion channelVoltage-gated ion channels are a class of transmembrane ion channels that are activated by changes in electrical potential difference near the channel; these types of ion channels are especially critical in neurons, but are common in many types of cells....
s - Ligand-gated ion channelLigand-gated ion channelLigand-gated ion channels are one type of ionotropic receptor or channel-linked receptor. They are a group of transmembrane ion channels that are opened or closed in response to the binding of a chemical messenger , such as a neurotransmitter.The binding site of endogenous ligands on LGICs...
s