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Roderick MacKinnon commissioned "Birth of an Idea", a 5' (1.50 m) tall sculpture based on the KcsA potassium channel. The artwork contains a wire object representing the pore liner with a blown glass object representing the main cavity of the channel structure.

Channel blockers are chemical substances, ranging from ions to complex organic molecules, that bind inside the pore of an ion channel and block the flow of ions through that channel. A subset of channel blockers, known as "open channel blockers" have access to their intra-channel binding site only when the channel is in the open configuration (i.e. in the configuration that conducts transmembrane ion flux). Open channel block is characterized by "flickery closings" in single-channel recordings.

Channels differ with respect to the ion they let pass (for example, Na+, K+, Cl?), the ways in which they may be regulated, the number of subunits of which they are composed and other aspects of structure. Channels belonging to the largest class, which includes the voltage-gated channels that underlie the nerve impulse, consists of four subunits with six transmembrane helices each. On activation, these helices move about and open the pore. Two of these six helices are separated by a loop that lines the pore and is the primary determinant of ion selectivity and conductance in this channel class

Potassium channels have a tetrameric structure in which four identical protein subunits associate to form a fourfold symmetric (C4) complex arranged around a central ion conducting pore (i.e., a homotetramer). Alternatively four related but not identical protein subunits may associate to form heterotetrameric complexes with pseudo C4 symmetry. All potassium channel subunits have a distinctive pore-loop structure that lines the top of the pore and is responsible for potassium selective permeability. There are over 80 mammalian genes that encode potassium channel subunits. However potassium channels found in bacteria are amongst the most studied of ion channels, in terms of their molecular

Transmembrane ion channel family was defined in InterPro and Pfam as the family of tetrameric sodium, potassium, and calcium ion channels, in which two C-terminal transmembrane helices flank a loop which determines ion selectivity of the channel pore. This large group of ion channels apparently includes families 1.A.1, 1.A.2, 1.A.3, and 1.A.4 of transporter classification. Many eukariotic channels have four additional transmembrane helices (TMH) (Pfam PF00520), whereas a bacterial structure of the protein has only two transmembrane helices that form the tetrameric channel (Pfam PF07885).

The T-type calcium channel is a type of voltage-dependent calcium channel. Like the others of this class, the ?1 subunit is the one that determines most of the channel's properties. Along with sodium "funny current," the T-type calcium channel produces the pacemaker potential in the SA node of the heart. T-type calcium channel blockers are used primarily as antiepileptics.

A Calcium channel is an ion channel which displays selective permeabiltiy to calcium ions. It is sometimes synonymous as voltage-dependent calcium channel,[1] although there are also ligand-gated calcium channels.[2]

A Calcium channel is an ion channel which displays selective permeabiltiy to calcium ions. It is sometimes synonymous as voltage-dependent calcium channel,[1] although there are also ligand-gated calcium channels.[2]

ATP binds to the extracellular loop of the P2X receptor, whereupon it evokes a conformational change in the structure of the ion channel that results in the opening of the ion-permeable pore. This allows cations such as Na+ and Ca2+ to enter the cell, leading to depolarization of the cell membrane and the activation of various Ca2+-sensitive intracellular processes. The channel opening time is dependent upon the subunit makeup of the receptor. For example, P2X1 and P2X3 receptors desensitize rapidly (a few hundred milliseconds) in the continued presence of ATP, whereas the P2X2 receptor channel remains open for as long

Potassium channel, subfamily K, member 2, also known as KCNK2, is a human gene.[1] This gene encodes K2P2.1, one of the members of the two-pore-domain background potassium channel protein family. This type of potassium channel is formed by two homodimers that create a channel that leaks potassium out of the cell to control resting membrane potential. The channel can be opened, however, by certain anesthetics, membrane stretching, intracellular acidosis, and heat. Three transcript variants encoding different isoforms have been found for this gene.

Chloride channel 6, also known as CLCN6, is a human gene.[1] The CLCN family of voltage-dependent chloride channel genes comprises nine members (CLCN1-7, Ka and Kb) which demonstrate quite diverse functional characteristics while sharing significant sequence homology. Chloride channel 6 and 7 belong to a subbranch of this family. Chloride channel 6 has four different alternatively spliced transcript variants. This gene is in close vicinity to two other kidney-specific chloride channel genes, CLCNKA and CLCNKB.[1]

Chloride channels are important for setting cell resting membrane potential and maintaining proper cell volume. These channels conduct Cl- as well as other anions such as HCO3-, I-, SCN-, and NO3-. The structure of these channels are not like other known channels. Chloride channel subunits contain between 1 and 12 transmembrane segments. Some members of this family are activated by voltage, while others are activated by Ca2+, extracellular ligands, and pH among other modulators.

The L-type calcium channel is a type of voltage-dependent calcium channel. Like the others of this class, the ?1 subunit is the one that determines most of the channel's properties. L-type calcium channel blocker drugs are used as cardiac antiarrhythmics or antihypertensives, depending on whether the drugs has higher affinity to the heart, the phenylalkylamines (like verapamil) or to the vessels, the dihydropyridines (nifedipine). L-type channels are selectively blocked by benzothiazepines (like diltiazem).

Sodium channels can often be isolated from cells as a complex of two types of protein subunits, ? and ?. An ? subunit forms the core of the channel. When the ? subunit protein is expressed by a cell, it is able to form channels which conduct Na+ in a voltage-gated way, even if ? subunits are not expressed. When ? subunits assemble with ? subunits the resulting complex can display altered voltage dependence and cellular localization. The ?-subunit has four repeat domains, labeled I through IV, each containing six membrane-spanning regions, labeled S1 through S6. The highly conserved S4 region

Potassium channel, subfamily K, member 17, also known as KCNK17, is a human gene.[1] This gene encodes K2P17.1, one of the members of the superfamily of potassium channel proteins containing two pore-forming P domains. This open channel, primarily expressed in the pancreas, is activated at alkaline pH.

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