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KCNQ1
Kv7.1 (KvLQT1) is a potassium channel protein whose primary subunit in humans is encoded by the ''KCNQ1'' gene. Kv7.1 is a voltage and lipid-gated potassium channel present in the cell membranes of cardiac tissue and in inner ear neurons among other tissues. In the cardiac cells, Kv7.1 mediates the IKs (or slow delayed rectifying K+) current that contributes to the repolarization of the cell, terminating the cardiac action potential and thereby the heart's contraction. It is a member of the KCNQ family of potassium channels. Structure KvLQT1 is made of six membrane-spanning domains S1-S6, two intracellular domains, and a pore loop. The KvLQT1 channel is made of four KCNQ1 subunits, which form the actual ion channel. Function This gene encodes a protein for a voltage-gated potassium channel required for the repolarization phase of the cardiac action potential. The gene product can form heteromultimers with two other potassium channel proteins, KCNE1 and KCNE3. The gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNE1
Potassium voltage-gated channel subfamily E member 1 is a protein that in humans is encoded by the ''KCNE1'' gene. Voltage-gated potassium channels (Kv) represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume.KCNE1is one of five members of the KCNE family of Kv channel ancillary or β subunits. It is also known as minK (minimal potassium channel subunit). Function KCNE1 is primarily known for modulating the cardiac and epithelial Kv channel alfa subunit, KCNQ1. KCNQ1 and KCNE1 form a complex in human ventricular cardiomyocytes that generates the slowly activating K+ current, IKs. Together with the rapidly activating K+ current (IKr), IKs is important for human ventricular repolarization. KCNQ1 is also essential for the norma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNE2
Potassium voltage-gated channel subfamily E member 2 (KCNE2), also known as MinK-related peptide 1 (MiRP1), is a protein that in humans is encoded by the ''KCNE2'' gene on chromosome 21. MiRP1 is a voltage-gated potassium channel accessory subunit (beta subunit) associated with Long QT syndrome. It is ubiquitously expressed in many tissues and cell types. Because of this and its ability to regulate multiple different ion channels, KCNE2 exerts considerable influence on a number of cell types and tissues. Human KCNE2 is a member of the five-strong family of human KCNE genes. KCNE proteins contain a single membrane-spanning region, extracellular N-terminal and intracellular C-terminal. KCNE proteins have been widely studied for their roles in the heart and in genetic predisposition to inherited cardiac arrhythmias. The ''KCNE2'' gene also contains one of 27 SNPs associated with increased risk of coronary artery disease. More recently, roles for KCNE proteins in a variety of non-card ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNE3
Potassium voltage-gated channel, Isk-related family, member 3 (KCNE3), also known as MinK-related peptide 2 (MiRP2) is a protein that in humans is encoded by the ''KCNE3'' gene. Function Voltage-gated potassium channels (Kv) represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. KCNE3 encodes a member of the five-strong KCNE family of voltage-gated potassium (Kv) channel ancillary or β subunits. KCNE3 is best known for modulating the KCNQ1 Kv α subunit, but it also regulates hERG, Kv2.1, Kv3.x, Kv4.x and Kv12.2 in heterologous co-expression experiments and/or in vivo. Co-assembly with KCNE3 converts KCNQ1 from a voltage-dependent delayed rectifier K+ channel to a constitutively open K+ channel with an almost linear curren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNE4
Potassium voltage-gated channel subfamily E member 4, originally named MinK-related peptide 3 or MiRP3 when it was discovered, is a protein that in humans is encoded by the ''KCNE4'' gene. Function Voltage-gated potassium channels (Kv) represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. The ''KCNE4'' gene encodes KCNE4 (originally named MinK-related peptide 3 or MiRP3), a member of the KCNE family of voltage-gated potassium (Kv) channel ancillary or β subunits. KCNE4 is best known for modulating the KCNQ1 Kv α subunit, but it also regulates KCNQ4, Kv1.x, Kv2.1, Kv4.x and BK α subunits in heterologous co-expression experiments and/or ''in vivo''. KCNE4 often, but not always, acts as an inhibitory subunit to suppress p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long QT Syndrome
Long QT syndrome (LQTS) is a condition affecting repolarization (relaxing) of the heart after a heartbeat, giving rise to an abnormally lengthy QT interval. It results in an increased risk of an irregular heartbeat which can result in fainting, drowning, seizures, or sudden death. These episodes can be triggered by exercise or stress. Some rare forms of LQTS are associated with other symptoms and signs including deafness and periods of muscle weakness. Long QT syndrome may be present at birth or develop later in life. The inherited form may occur by itself or as part of larger genetic disorder. Onset later in life may result from certain medications, low blood potassium, low blood calcium, or heart failure. Medications that are implicated include certain antiarrhythmics, antibiotics, and antipsychotics. LQTS can be diagnosed using an electrocardiogram (EKG) if a corrected QT interval of greater than 480–500 milliseconds is found, but clinical findings, other EKG features, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNE5
KCNE1-like also known as KCNE1L is a protein that in humans is encoded by the ''KCNE1L'' gene. Function Voltage-gated potassium ( Kv) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. ''KCNE5'' encodes a membrane protein, KCNE5 (originally named KCNE1-L) that has sequence similarity to the KCNE1 gene product, a member of the potassium channel, voltage-gated, isk-related subfamily. The ''KCNE'' gene family comprises five genes in the human genome, each encoding a type I membrane protein. The KCNE subunits are potassium channel regulatory subunits that do not pass currents themselves but alter the properties of potassium channel pore-forming alpha subunits. KCNE5 is thus far the least-studied member of the KCNE f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AKAP9
A-kinase anchor protein 9 is a protein that in humans is encoded by the ''AKAP9'' gene. AKAP9 is also known as Centrosome- and Golgi-localized protein kinase N-associated protein (CG-NAP) or AKAP350 or AKAP450 Function The A-kinase anchor proteins (AKAPs) are a group of structurally diverse proteins which have the common function of binding to the regulatory subunit of protein kinase A (PKA) and confining the holoenzyme to discrete locations within the cell. This gene encodes a member of the AKAP family. Alternate splicing of this gene results in many isoforms that localize to the centrosome and the Golgi apparatus, and interact with numerous signaling proteins from multiple signal transduction pathways. These signaling proteins include type II protein kinase A, serine/threonine kinase protein kinase N, protein phosphatase 1, protein phosphatase 2a, protein kinase C-epsilon and phosphodiesterase 4D3. Model organisms Model organisms have been used in the study of AKAP9 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid-gated Ion Channels
Lipid-gated ion channels are a class of ion channels whose conductance of ions through the membrane depends directly on lipids. Classically the lipids are membrane resident anionic signaling lipids that bind to the transmembrane domain on the inner leaflet of the plasma membrane with properties of a classic ligand. Other classes of lipid-gated channels include the mechanosensitive ion channels that respond to lipid tension, thickness, and hydrophobic mismatch. A lipid ligand differs from a lipid cofactor in that a ligand derives its function by dissociating from the channel while a cofactor typically derives its function by remaining bound. PIP2-gated channels Phosphatidylinositol 4,5-bisphosphate (PIP2) was the first and remains the best studied lipid to gate ion channels. PIP2 is a cell membrane lipid, and its role in gating ion channels represents a novel role for the molecule. Kir channels: PIP2 binds to and directly activates inwardly rectifying potassium channels (Kir) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PPP1CA
Serine/threonine-protein phosphatase PP1-alpha catalytic subunit is an enzyme that in humans is encoded by the ''PPP1CA'' gene. Function The protein encoded by this gene is one of the three catalytic subunits of protein phosphatase 1 (PP1). PP1 is a serine/threonine specific protein phosphatase known to be involved in the regulation of a variety of cellular processes, such as cell division, glycogen metabolism, muscle contractility, protein synthesis, and HIV-1 viral transcription. Increased PP1 activity has been observed in the end stage of heart failure. Studies in both human and mice suggest that PP1 is an important regulator of cardiac function. Mouse studies also suggest that PP1 functions as a suppressor of learning and memory. Three alternatively spliced transcript variants encoding different isoforms have been found for this gene. Interactive pathway map Interactions PPP1CA has been shown to interact with: * AKAP11, * BCL2-like 1, * BCL2L2, * BRCA1, * CDC5L, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short QT Syndrome
Short QT syndrome (SQT) is a very rare genetic disease of the electrical system of the heart, and is associated with an increased risk of abnormal heart rhythms and sudden cardiac death. The syndrome gets its name from a characteristic feature seen on an electrocardiogram (ECG) – a shortening of the QT interval. It is caused by mutations in genes encoding ion channels that shorten the cardiac action potential, and appears to be inherited in an autosomal dominant pattern. The condition is diagnosed using a 12-lead ECG. Short QT syndrome can be treated using an implantable cardioverter-defibrillator or medications including quinidine. Short QT syndrome was first described in 2000, and the first genetic mutation associated with the condition was identified in 2004. Signs and symptoms Those affected by short QT syndrome (SQT) have an increased risk of developing abnormal heart rhythms. These abnormal heart rhythms often occur at a young age. They may take relatively ben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KCNQ Channels
KCQN genes encode family members of the Kv7 potassium channel family. These include Kv7.1 (KCNQ1) - KvLQT1, Kv7.2 (KCNQ2), Kv7.3 (KCNQ3), Kv7.4 (KCNQ4), and Kv7.5 ( KCNQ5). Four of these (KCNQ2-5) are expressed in the nervous system. They constitute a group of low-threshold voltage-gated K+ channels originally termed the ‘M-channel’ (see M-current). The M-channel name comes from the classically described mechanism wherein the activation of the muscarinic acetylcholine receptor Muscarinic acetylcholine receptors, or mAChRs, are acetylcholine receptors that form G protein-coupled receptor complexes in the cell membranes of certain neurons and other cells. They play several roles, including acting as the main end-rece ... deactivated this channel. References Potassium channels Ion channels {{Molecular-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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