 | |
| Content | |
|---|---|
| Description | Voltage-gated potassium channel database. |
| Contact | |
| Research center | University of Alberta |
| Laboratory | Department of Biological Sciences |
| Authors | Bin Li |
| Primary citation | Li & al. (2004) [1] |
| Release date | 2004 |
| Access | |
| Website | http://vkcdb.biology.ualberta.ca |
VKCDB (Voltage-gated potassium Channel DataBase) is a database of functional data about the voltage-gated potassium channels. [1]
Ion channels are pore-forming membrane proteins that allow ions to pass through the channel pore. Their 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 one of the two classes of ionophoric proteins, the other being ion transporters.
Inward-rectifier potassium channels (Kir, IRK) are a specific lipid-gated subset of potassium channels. To date, seven subfamilies have been identified in various mammalian cell types, plants, and bacteria. They are activated by phosphatidylinositol 4,5-bisphosphate (PIP2). The malfunction of the channels has been implicated in several diseases. IRK channels possess a pore domain, homologous to that of voltage-gated ion channels, and flanking transmembrane segments (TMSs). They may exist in the membrane as homo- or heterooligomers and each monomer possesses between 2 and 4 TMSs. In terms of function, these proteins transport potassium (K+), with a greater tendency for K+ uptake than K+ export. The process of inward-rectification was discovered by Denis Noble in cardiac muscle cells in 1960s and by Richard Adrian and Alan Hodgkin in 1970 in skeletal muscle cells.
The Hodgkin–Huxley model, or conductance-based model, is a mathematical model that describes how action potentials in neurons are initiated and propagated. It is a set of nonlinear differential equations that approximates the electrical engineering characteristics of excitable cells such as neurons and muscle cells. It is a continuous-time dynamical system.
Potassium voltage-gated channel subfamily A member 1 also known as Kv1.1 is a shaker related voltage-gated potassium channel that in humans is encoded by the KCNA1 gene. Isaacs syndrome is a result of an autoimmune reaction against the Kv1.1 ion channel.
Calcium-activated potassium channels are potassium channels gated by calcium, or that are structurally or phylogenetically related to calcium gated channels. They were first discovered in 1958 by Gardos who saw that calcium levels inside of a cell could affect the permeability of potassium through that cell membrane. Then in 1970, Meech was the first to observe that intracellular calcium could trigger potassium currents. In humans they are divided into three subtypes: large conductance or BK channels, which have very high conductance which range from 100 to 300 pS, intermediate conductance or IK channels, with intermediate conductance ranging from 25 to 100 pS, and small conductance or SK channels with small conductances from 2-25 pS.
Voltage-gated potassium channels (VGKCs) are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized cell to a resting state.
Potassium voltage-gated channel, shaker-related subfamily, member 5, also known as KCNA5 or Kv1.5, is a protein that in humans is encoded by the KCNA5 gene.
Potassium voltage-gated channel subfamily D member 3 also known as Kv4.3 is a protein that in humans is encoded by the KCND3 gene. It contributes to the cardiac transient outward potassium current (Ito1), the main contributing current to the repolarizing phase 1 of the cardiac action potential.
Potassium voltage-gated channel subfamily H member 1 is a protein that in humans is encoded by the KCNH1 gene.
Voltage-gated potassium channel subunit beta-1 is a protein that in humans is encoded by the KCNAB1 gene.
Voltage-gated potassium channel subunit beta-2 is a protein that in humans is encoded by the KCNAB2 gene.
Potassium voltage-gated channel, Shaw-related subfamily, member 4 (KCNC4), also known as Kv3.4, is a human gene.
Potassium voltage-gated channel subfamily S member 3 (Kv9.3) is a protein that in humans is encoded by the KCNS3 gene. KCNS3 gene belongs to the S subfamily of the potassium channel family. It is highly expressed in pulmonary artery myocytes, placenta, and parvalbumin-containing GABA neurons in brain cortex. In humans, single-nucleotide polymorphisms of the KCNS3 gene are associated with airway hyperresponsiveness, whereas decreased KCNS3 mRNA expression is found in the prefrontal cortex of patients with schizophrenia.
Potassium voltage-gated channel, subfamily H (eag-related), member 5, also known as KCNH5, is a human gene encoding the Kv10.2 protein.
Potassium voltage-gated channel, Shal-related subfamily, member 1 (KCND1), also known as Kv4.1, is a human gene.
Potassium voltage-gated channel, Shaw-related subfamily, member 3 also known as KCNC3 or Kv3.3 is a protein that in humans is encoded by the KCNC3.
Potassium voltage-gated channel subfamily A member 6 also known as Kv1.6 is a protein that in humans is encoded by the KCNA6 gene. The protein encoded by this gene is a voltage-gated potassium channel subunit.
Potassium voltage-gated channel subfamily G member 2 is a protein that in humans is encoded by the KCNG2 gene. The protein encoded by this gene is a voltage-gated potassium channel subunit.
Potassium voltage-gated channel subfamily S member 2 is a protein that in humans is encoded by the KCNS2 gene. The protein encoded by this gene is a voltage-gated potassium channel subunit.
Potassium voltage-gated channel subfamily H member 3 is a protein that in humans is encoded by the KCNH3 gene. The protein encoded by this gene is a voltage-gated potassium channel subunit.
 | This Biological database-related article is a stub. You can help Wikipedia by expanding it. |
 | This article related to medical imaging is a stub. You can help Wikipedia by expanding it. |