Wiktionary
n. (context biochemistry English) a protein complex or single protein#Noun which penetrates a cell membrane and catalyzes the passage of specific ion#Noun through that membrane.
Wikipedia
Ion channels are pore-forming membrane proteins whose functions include establishing a resting membrane potential, shaping action potentials and other electrical signals by gating the flow of ions across the cell membrane, controlling the flow of ions across secretory and epithelial cells, and regulating cell volume. Ion channels are present in the membranes of all cells. Ion channels are considered to be one of the two traditional classes of ionophoric proteins, with the other class known as ion transporters (including the sodium-potassium pump, sodium-calcium exchanger, and sodium-glucose transport proteins, amongst others).
Study of ion channels ( channelomics) often includes biophysics, electrophysiology and pharmacology, utilizing techniques including voltage clamp, patch clamp, immunohistochemistry, X-ray crystallography, fluorescence, and RT-PCR.
Usage examples of "ion channel".
This gene encoded a different regulatory protein, which provided a sodium ion channel on the surface of heart cells.
Small, but HERG contained instructions for the assembly of a protein that served as a potassium ion channel in the surface of heart cells, and these ion channels acted as a switch to turn off contracting heart cells.