Stretch-activated ion channel

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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.

Contents 1 Mechanism 2 Functions 3 Example 4 See also 5 References

[edit] Mechanism

Though little is known about these channels, they may be linked to molecules in the cytoskeleton, which may open them by transmitting physical forces of stretch or pressure to the channels, causing them to undergo a conformational change.^[1] The channels may also be pulled open due to tension on the membrane itself.^[1] Opening the channels allows ions to which they are permeable to flow down their electrochemical gradients 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.

[edit] Functions

Such channels are of use in the initial formation of an action potential from a mechanical stimulus, for example by the mechanoreceptors in an animal's vibrissae (whiskers).

[edit] Example

An example is "MID-1" (also known as "MCLC" or CLCC1.)^[2][3]

[edit] See also

• Mechanosensitive ion channel
• Large-conductance mechanosensitive channel
• Voltage-gated ion channels
• Ligand-gated ion channels

[edit] References

1. ^ ^{a b} Kandel ER, Schwartz JH, Jessell TM. Principles of Neural Science, 4th ed., Pages 113-114. McGraw-Hill, New York (2000). ISBN 0-8385-7701-6
2. ^ Nagasawa M, Kanzaki M, Iino Y, Morishita Y, Kojima I (2001). "Identification of a novel chloride channel expressed in the endoplasmic reticulum, golgi apparatus, and nucleus". J. Biol. Chem. 276 (23): 20413–8. doi:10.1074/jbc.M100366200. PMID 11279057. 
3. ^ Ozeki-Miyawaki C, Moriya Y, Tatsumi H, Iida H, Sokabe M (2005). "Identification of functional domains of Mid1, a stretch-activated channel component, necessary for localization to the plasma membrane and Ca2+ permeation". Exp. Cell Res. 311 (1): 84–95. doi:10.1016/j.yexcr.2005.08.014. PMID 16202999. 

v • d • e Membrane transport protein: ion channels Ca2+: Calcium channel Voltage-dependent calcium channel (L-type/Cavα(1.1, 1.2, 1.3, 1.4), N-type, P-type/Cavα(2.1), Q-type, R-type, T-type, α2δ-subunits (1, 2), β-subunits (β1, β2, β3, β4), γ-subunits (γ1, γ2, γ3, γ4) Inositol triphosphate receptor • Ryanodine receptor • Cation channels of sperm • Two-pore channel Na+: Sodium channel Navα (1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.9, 7A) • Navβ (1, 2, 3, 4) • Epithelial sodium channel K+: Potassium channel Voltage-gated (Kvα (1.1, 1.2, 1.3, 1.4, 1.5, 2.1, 3.1, 3.4, 4.1, 4.2, 4.3, 6.1, 7.1, 7.2, 7.3, 7.4, 7.5, 9.3, 10.1, 11.1/hERG) • Kvβ (1, 2), Shaker gene, KCNE1) Calcium-activated (BK channel: α1, β1, β2, β3, β4; SK channel: SK1, SK2, SK3, SK4) Inward-rectifier Kir (1.1, 2.1, 2.2, 2.3, 2.4, GIRK, 3.1, 3.2, 3.3, 3.4, 4.1, 4.2, 5.1, 6.1, 6.2, 7.1) Tandem pore domain K2P (1, 2, 3, 4, 6, 9, 15, 17) Cl-: Chloride channel Cystic fibrosis transmembrane conductance regulator Porin Aquaporin (1, 2, 3, 4, 5, 7, 8, 9) • Voltage-dependent anion channel (1) Cations: TRP TRPA (1) • TRPC (1, 2, 3, 4, 4AP, 5, 6, 7) • TRPM (1, 2, 3, 4, 5, 6, 7, 8) • TRPML (Mucolipin-1) • TRPP (1, 2) • TRPV (1, 2, 3, 4, 5, 6) Other/general Voltage-gated ion channel • Ligand-gated ion channel • Cyclic nucleotide-gated ion channel (α1, α2, α3, β1, β3, H1, H2, H3, H4) • Stretch-activated ion channel