| Type |
Details |
Score |
| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The THIK (Tandem pore-domain Halothane Inhibited K+ channel) family contains two members: THIK-1 and THIK-2. Both proteins were first isolated from rat and have subsequently been found in human. THIK-1 is expressed ubiquitously and is activated by arachidonic acid and inhibited by the volatile anaesthetic halothane. The second member, THIK-2, shares 58% amino acid identity with THIK-1, but is not functionally expressed. THIK-2 is strongly expressed in several tissues, and is particularly abundant in the brain []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.2P-domain channels influence the resting membrane potential and as a result can control cell excitability. In addition, they pass K+in response to changes in membrane potential, and are also tightly regulated by molecular oxygen, GABA (gamma-aminobutyric acid), noradrenaline and serotonin.The first member of this family (TOK1), cloned from Saccharomyces cerevisiae [], ispredicted to have eight potential transmembrane (TM) helices. However,subsequently-cloned two P-domain family members from Drosophila andmammalian species are predicted to have only four TM segments. They areusually referred to as TWIK-related channels (Tandem of P-domains in a Weakly Inward rectifying K+ channel) [, , , ]. Functional characterisation of these channels has revealed a diversity of properties in that they may show inward or outward rectification, their activity may be modulated in different directions by protein phosphorylation, and their sensitivity to changes in intracellular or extracellular pH varies. Despite these disparate properties, they are all thought to share the same topology offour TM segments, including two P-domains. That TWIK-related K+ channelsall produce instantaneous and non-inactivating K+ currents, which do notdisplay a voltage-dependent activation threshold, suggests that they arebackground (leak) K+ channels involved in the generation and modulation of the resting membrane potential in various cell types. Further studies have revealed that they may be found in many species, including: plants, invertebrates and mammals. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The Kv family can be divided into several subfamilies on the basis of sequence similarity and function. Four of these subfamilies, Kv1 (Shaker), Kv2 (Shab), Kv3 (Shaw) and Kv4 (Shal), consist of pore-forming alpha subunits that associate with different types of beta subunit. Each alpha subunit comprises six hydrophobic TM domains with a P-domain between the fifth and sixth, which partially resides in the membrane. The fourth TM domain has positively charged residues at every third residue and acts as a voltage sensor, which triggers the conformational change that opens the channel pore in response to a displacement in membrane potential []. More recently, 4 new electrically-silent alpha subunits have been cloned: Kv5 (KCNF), Kv6 (KCNG), Kv8 and Kv9 (KCNS). These subunits do not themselves possess any functional activity, but appear to form heteromeric channels with Kv2 subunits, and thus modulate Shab channel activity []. When highly expressed, they inhibit channel activity, but at lower levels show more specific modulatory actions.A voltage-dependent potassium channel gene designated Shaw was initially isolated from Drosophila melanogaster (Fruit fly). Subsequently, several vetebrate potassium channels with similar amino acid sequences were found and, together with the D. melanogaster channel, now constitute the Kv3 family. These channels are thought to play a role in shortening of action potential durations and modulating pre-synaptic neurotransmitter release. In mammals, the family consists of 4 genes (Kv3.1, Kv3.2, Kv3.3 and Kv3.4). Each gene product has its own subcellular location and function. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. Thefunctional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The KCNAB family (also known as the Kvbeta family) of voltage-dependent potassium channel beta subunits form complexes with the alpha subunits which can modify the properties of the channel. Four of these soluble beta subunits form a complex with four alpha subunit cytoplasmic (T1) regions. These subunits belong to the family of are NADPH-dependent aldo-keto reductases, and bind NADPH-cofactors in their active sites. Changes in the oxidoreductase activity appear to markedly influence the gating mode of Kv channels, since mutations to the catalytic residues in the active site lessen the inactivating activity of KCNAB []. The KCNAB family is further divided into 3 subfamilies: KCNAB1 (Kvbeta1), KCNAB2 (Kvbeta2) and KCNAB3 (Kvbeta3).KCNAB3 associates with Kv1.5 alpha subunits, resulting in a much faster inactivation than is observed in kv1.5 channels formed from alpha subunitsalone []. KCNAB3 channels are expressed specifically in the brain, with most prominent expression in the cerebellum. Weaker expression is observed in the cortex, occipital lobe, frontal lobe and temporal lobe. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The KCNAB family (also known as the Kvbeta family) of voltage-dependent potassium channel beta subunits form complexes with the alpha subunits which can modify the properties of the channel. Four of these soluble beta subunits form a complex with four alpha subunit cytoplasmic (T1) regions. These subunits belong to the family of are NADPH-dependent aldo-keto reductases, and bind NADPH-cofactors in their active sites. Changes in the oxidoreductase activity appear to markedly influence the gating mode of Kv channels, since mutations to the catalytic residues in the active site lessen the inactivating activity of KCNAB []. The KCNAB family is further divided into 3 subfamilies: KCNAB1 (Kvbeta1), KCNAB2 (Kvbeta2) and KCNAB3 (Kvbeta3).KCNAB1 associates with Kv1.4 and Kv1.5 alpha subunits and appears to have an N-terminal sequence that is similar to the Kv1 channel inactivation gate.Thus, when KCNAB1 subunits associate, their N-termini appear to be able to substitute for alpha subunit inactivation gates []. Three isoforms of KCNAB1 exist, which are produced by alternative splicing of the N-terminal90 amino acids. KCNAB1 channels are expressed in brain (caudate nucleus,hippocampus, amygdala, subthalamic nucleus and thalamus) and heart. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The KCNAB family (also known as the Kvbeta family) of voltage-dependent potassium channel beta subunits form complexes with the alpha subunits which can modify the properties of the channel. Four of these soluble beta subunits form a complex with four alpha subunit cytoplasmic (T1) regions. These subunits belong to the family of are NADPH-dependent aldo-keto reductases, and bind NADPH-cofactors in their active sites. Changes in the oxidoreductase activity appear to markedly influence the gating mode of Kv channels, since mutations to the catalytic residues in the active site lessen the inactivating activity of KCNAB []. The KCNAB family is further divided into 3 subfamilies: KCNAB1 (Kvbeta1), KCNAB2 (Kvbeta2) and KCNAB3 (Kvbeta3).KCNAB2 associates with Kv1.4 alpha subunits; however, association has onlyvery modest effects on the gating of this channel []. Two isoforms of KCNAB2exist, which are produced by alternative splicing of amino acids 26-39. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.2P-domain channels influence the resting membrane potential and as a result can control cell excitability. In addition, they pass K+in response to changes in membrane potential, and are also tightly regulated by molecular oxygen, GABA (gamma-aminobutyric acid), noradrenaline and serotonin.The first member of this family (TOK1), cloned from Saccharomyces cerevisiae [], ispredicted to have eight potential transmembrane (TM) helices. However,subsequently-cloned two P-domain family members from Drosophila andmammalian species are predicted to have only four TM segments. They areusually referred to as TWIK-related channels (Tandem of P-domains in a Weakly Inward rectifying K+ channel) [, , , ]. Functional characterisation of these channels has revealed a diversity of properties in that they may show inward or outward rectification, their activity may be modulated in different directions by protein phosphorylation, and their sensitivity to changes in intracellular or extracellular pH varies. Despite these disparate properties, they are all thought to share the same topology offour TM segments, including two P-domains. That TWIK-related K+ channelsall produce instantaneous and non-inactivating K+ currents, which do notdisplay a voltage-dependent activation threshold, suggests that they arebackground (leak) K+ channels involved in the generation and modulation of the resting membrane potential in various cell types. Further studies have revealed that they may be found in many species, including: plants, invertebrates and mammals. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.KCNQ channels (also known as KQT-like channels) differ from other voltage-gated 6 TM helix channels, chiefly in that they possess no tetramerisation domain. Consequently, they rely on interaction with accessory subunits, or form heterotetramers with other members of the family []. Currently, 5 members of the KCNQ family are known. These have been found to be widely distributed within the body, having been shown to be expressed in the heart, brain, pancreas, lung, placenta and ear. They were initially cloned as a result of a search for proteins involved in cardiac arhythmia. Subsequently, mutations in other KCNQ family members have been shown to be responsible for some forms of hereditary deafness []and benign familial neonatal epilepsy [].KCNQ1 was the first member of the KCNQ channel family to be isolated, and has been found to be the most common cause of the disease `long QT syndrome' a cardiac arhythmia resulting in a prolonged QT interval. In exceptional cases, this can lead to sudden death, triggered by extreme stress [, ]. KCNQ1 is expressed in the stria vascularis of the inner ear, and may be the cause of hereditary deafness []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.Ca2+-activated K+ channels are a diverse group of channels that are activated by an increase in intracellular Ca2+ concentration. They are found in the majority of nerve cells, where they modulate cell excitability and action potential. Three types of Ca2+-activated K+ channel have been characterised, termed small-conductance (SK), intermediate conductance (IK) and large conductance (BK) respectively [].SK channels are thought to play an important role in the functioning of all excitable tissues. To date, 3 subtypes (designated SK1-SK3) have been cloned, each of which possesses a different tissue expression profile: SK1 channels are expressed in the heart; SK2 channels are found in the adrenal gland; and SK3 channels are known to be present in skeletal muscle []. SK channels have a single-channel conductance of 2-20 pS and are activated by rises in cytosolic calcium with half maximal activation in the 400-800 nM range [, ]. Unlike BK channels, they are voltage insensitive and unaffected by low concentrations of TEA, charybdotoxin, or iberiotoxin. However, they are potently blocked by the bee venom apamin [, ], tubocurarine, and quaternary salts of bicuculline [, ]. A new series of compounds that block SK channels include dequalinium |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.KCNQ channels (also known as KQT-like channels) differ from other voltage-gated 6 TM helix channels, chiefly in that they possess no tetramerisation domain. Consequently, they rely on interaction with accessory subunits, or form heterotetramers with other members of the family []. Currently, 5 members of the KCNQ family are known. These have been found to be widely distributed within the body, having been shown to be expressed in the heart, brain, pancreas, lung, placenta and ear. They were initially cloned as a result of a search for proteins involved in cardiac arhythmia. Subsequently, mutations in other KCNQ family members have been shown to be responsible for some forms of hereditary deafness []and benign familial neonatal epilepsy [].KCNQ4 gene maps to the DFNA2 locus for a form of nonsyndromic dominant deafness. In the cochlea, it is expressed in sensory outer hair cells []. |
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| Protein Domain |
| Type: |
Domain |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.BK channels (also referred to as high-conductance, maxi-K channels or Slo family channels) []are widely expressed in the body, being found in glandular tissue, smooth and skeletal muscle, as well as in neural tissues. They have been demonstrated to regulate arteriolar and airway diameter, and also neurotransmitter release. Each channel complex is thought to be composed of 2 types of subunit; the pore-forming (alpha) subunits and smaller accessory (beta) subunits.The alpha subunit of the BK channel was initially thought to share the characteristic 6TM organisation of the voltage-gated K+ channels. However, the molecule is now thought to possess an additional TM domain, with an extracellular N terminus and intracellular C terminus. This C-terminal region contains 4 predominantly hydrophobic domains, which are also thought to lie intracellularly. The extracellular N terminus and the first TM region are required for modulation by the beta subunit. The precise location of the Ca2+-binding site that modulates channel activation remains unknown, but it is thought to lie within the C-terminal hydrophobic domains.The sodium-activated potassium channels Slick (Slo2.1, KCNT2) and Slack (Slo2.2, KCNT1) belong to the structurally related high-conductance potassium channels of the Slo family []. Slo3, also a member of the Slo family, is exclusively expressed in mammalian sperm []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The first EAG K+ channel was identified in Drosophila melanogaster (Fruit fly), following a screen for mutations giving rise to behavioural abnormalities. Disruption of the Eag gene caused an ether-induced, leg-shaking behaviour. Subsequent studies have revealed a conserved multi-gene family of EAG-like K+ channels, which are present in human and many other species. Based on the varying functional properties of the channels, the family has been divided into 3 subfamilies: EAG, ELK and ERG. Interestingly, Caenorhabditis elegans appears to lack the ELK type [].Little is known about the properties of channels of the ELK subfamily. However, when expressed in frog oocytes, they show properties between thoseof the EAG and ERG subtypes. Included in this family are Bec1 and Bec2,brain-specific genes found in the human telencephalon regions. It is thoughtthat they are involved in cellular excitability of restricted neurons in thehuman central nervous system. Phylogenetic analysis reveals that these genesconstitute a subfamily with Elk within the Eag family []. Recently, afurther Elk subfamily member has been identified in the mouse (Melk). On thebasis of sequence similarity, this indicates a distinct subclass within this family []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The Kv family can be divided into several subfamilies on the basis of sequence similarity and function. Four of these subfamilies, Kv1 (Shaker), Kv2 (Shab), Kv3 (Shaw) and Kv4 (Shal), consist of pore-forming alpha subunits that associate with different types of beta subunit. Each alpha subunit comprises six hydrophobic TM domains with a P-domain between the fifth and sixth, which partially resides in the membrane. The fourth TM domain has positively charged residues at every third residue and acts as a voltage sensor, which triggers the conformational change that opens the channel pore in response to a displacement in membrane potential []. More recently, 4 new electrically-silent alpha subunits have been cloned: Kv5 (KCNF), Kv6 (KCNG), Kv8 and Kv9 (KCNS). These subunits do not themselves possess any functional activity, but appear to form heteromeric channels with Kv2 subunits, and thus modulate Shab channel activity []. When highly expressed, they inhibit channel activity, but at lower levels show more specific modulatory actions.Coexpression of Kv6 subunits with Kv2 subunits has a slowing effect on Kv2 channel inactivation at strong depolarising potentials, but has little effect on channel inactivation at intermediate potentials []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others inresponse to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The Kv family can be divided into several subfamilies on the basis of sequence similarity and function. Four of these subfamilies, Kv1 (Shaker), Kv2 (Shab), Kv3 (Shaw) and Kv4 (Shal), consist of pore-forming alpha subunits that associate with different types of beta subunit. Each alpha subunit comprises six hydrophobic TM domains with a P-domain between the fifth and sixth, which partially resides in the membrane. The fourth TM domain has positively charged residues at every third residue and acts as a voltage sensor, which triggers the conformational change that opens the channel pore in response to a displacement in membrane potential []. More recently, 4 new electrically-silent alpha subunits have been cloned: Kv5 (KCNF), Kv6 (KCNG), Kv8 and Kv9 (KCNS). These subunits do not themselves possess any functional activity, but appear to form heteromeric channels with Kv2 subunits, and thus modulate Shab channel activity []. When highly expressed, they inhibit channel activity, but at lower levels show more specific modulatory actions.Coexpression of Kv8 subunits with Kv2 subunits produces altered channel-activation kinetics that do not fit the standard model. In addition, channel inactivation shows a shift in voltage-dependence toward more negative potentials and a slower time course. TM domain 6 is thought to play a key role in these modulatory effects []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependentgating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.The Kv family can be divided into several subfamilies on the basis of sequence similarity and function. Four of these subfamilies, Kv1 (Shaker), Kv2 (Shab), Kv3 (Shaw) and Kv4 (Shal), consist of pore-forming alpha subunits that associate with different types of beta subunit. Each alpha subunit comprises six hydrophobic TM domains with a P-domain between the fifth and sixth, which partially resides in the membrane. The fourth TM domain has positively charged residues at every third residue and acts as a voltage sensor, which triggers the conformational change that opens the channel pore in response to a displacement in membrane potential []. More recently, 4 new electrically-silent alpha subunits have been cloned: Kv5 (KCNF), Kv6 (KCNG), Kv8 and Kv9 (KCNS). These subunits do not themselves possess any functional activity, but appear to form heteromeric channels with Kv2 subunits, and thus modulate Shab channel activity []. When highly expressed, they inhibit channel activity, but at lower levels show more specific modulatory actions.Coexpression of Kv9 subunits with Shab subunits produces a shift in the voltage-dependence of channel inactivation toward more negative potentials []. In addition, Shab channel deactivation and inactivation are slowed, and the single channel conductance is increased []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.Ca2+-activated K+ channels are a diverse group of channels that are activated by an increase in intracellular Ca2+ concentration. They are found in the majority of nerve cells, where they modulate cell excitability and action potential. Three types of Ca2+-activated K+ channel have been characterised, termed small-conductance (SK), intermediate conductance (IK) and large conductance (BK) respectively [].BK channels (also referred to as maxi-K channels) are widely expressed in the body, being found in glandular tissue, smooth and skeletal muscle, as well as in neural tissues. They have been demonstrated to regulate arteriolar and airway diameter, and also neurotransmitter release. Eachchannel complex is thought to be composed of 2 types of subunit: the pore-forming (alpha) subunits and smaller accessory (beta) subunits.The beta subunit (which is thought to possess 2 TM domains) increases theCa2+ sensitivity of the BK channel []. It does this by enhancing the timespent by the channel in burst-like open states. However, it has little effect on the durations of closed intervals between bursts, or on thenumbers of open and closed states entered during gating []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. Theyare important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.KCNQ channels (also known as KQT-like channels) differ from other voltage-gated 6 TM helix channels, chiefly in that they possess no tetramerisation domain. Consequently, they rely on interaction with accessory subunits, or form heterotetramers with other members of the family []. Currently, 5 members of the KCNQ family are known. These have been found to be widely distributed within the body, having been shown to be expressed in the heart, brain, pancreas, lung, placenta and ear. They were initially cloned as a result of a search for proteins involved in cardiac arhythmia. Subsequently, mutations in other KCNQ family members have been shown to be responsible for some forms of hereditary deafness []and benign familial neonatal epilepsy [].The KCNQ2 channel subunit is thought to form active channels by hetero- tetramerisation with KCNQ3, although some K+ channel activity does results from the expression of KCNQ2 alone []. Channel function is modulated by phosphorylation, since experiments have demonstrated that an increase in intracellular cAMP concentration can enhance channel activity. Frameshift mutations in both KCNQ2 and KCNQ3 are associated with benign familial neonatal epilepsy [], a disorder where an infant begins to suffer convulsions, within the first three days of life. These symptoms usually disappear after approximately three months, but affected individuals have a higher than average chance of subsequently developing epilepsy (10-15%), in later life []. |
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| Protein Domain |
| Type: |
Family |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.KCNQ channels (also known as KQT-like channels) differ from other voltage-gated 6 TM helix channels, chiefly in that they possess no tetramerisation domain. Consequently, they rely on interaction with accessory subunits, or form heterotetramers with other members of the family []. Currently, 5 members of the KCNQ family are known. These have been found to be widely distributed within the body, having been shown to be expressed in the heart, brain, pancreas, lung, placenta and ear. They were initially cloned as a result of a search for proteins involved in cardiac arhythmia. Subsequently, mutations in other KCNQ family members have been shown to be responsible for some forms of hereditary deafness []and benign familial neonatal epilepsy [].The KCNQ3 channel subunit is thought to form active channels by hetero- tetramerisation with KCNQ2, although some K+ channel activity does result from the expression of KCNQ3 alone []. Channel function is modulated by phosphorylation; experiments have demonstrated that an increase in intracellular cAMP concentration can enhance channel activity. Frameshift mutations in both KCNQ2 and KCNQ3 are associated with benign familial neonatal epilepsy [], a disorder in which infants suffer convulsions within the first 3 days of life. These symptoms usually disappear after about 3 months, but affected individuals have a higher than average chance of subsequently developing epilepsy (10-15%) in later life []. |
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| Protein Domain |
| Type: |
Domain |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.Inwardly-rectifying potassium channels (Kir) are the principal class of two-TM domain potassium channels. They are characterised by the property of inward-rectification, which is described as the ability to allow large inward currents and smaller outward currents. Inwardly rectifying potassium channels (Kir) are responsible for regulating diverse processes including: cellular excitability, vascular tone, heart rate, renal salt flow, and insulin release []. To date, around twenty members of this superfamily have been cloned, which can be grouped into six families by sequence similarity, and these are designated Kir1.x-6.x [, ].Cloned Kir channel cDNAs encode proteins of between ~370-500 residues, both N- and C-termini are thought to be cytoplasmic, and the N terminus lacks a signal sequence. Kir channel alpha subunits possess only 2TM domains linked with a P-domain. Thus, Kir channels share similarity with the fifth and sixth domains, and P-domain of the other families. It is thought that four Kir subunits assemble to form a tetrameric channel complex, which may be hetero- or homomeric [].This metazoan domain is found to the N terminus of Inward rectifier potassium channels (KIR2 or IRK2). |
|
•
•
•
•
•
|
| Protein Domain |
| Type: |
Homologous_superfamily |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there are K+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.Inwardly-rectifying potassium channels (Kir) are the principal class of two-TM domain potassium channels. They are characterised by the property of inward-rectification, which is described as the ability to allowlarge inward currents and smaller outward currents. Inwardly rectifying potassium channels (Kir) are responsible for regulating diverse processes including: cellular excitability, vascular tone, heart rate, renal salt flow, and insulin release []. To date, around twenty members of this superfamily have been cloned, which can be grouped into six families by sequence similarity, and these are designated Kir1.x-6.x [, ].Cloned Kir channel cDNAs encode proteins of between ~370-500 residues, both N- and C-termini are thought to be cytoplasmic, and the N terminus lacks a signal sequence. Kir channel alpha subunits possess only 2TM domains linked with a P-domain. Thus, Kir channels share similarity with the fifth and sixth domains, and P-domain of the other families. It is thought that four Kir subunits assemble to form a tetrameric channel complex, which may be hetero- or homomeric []. |
|
•
•
•
•
•
|
| Protein Domain |
| Type: |
Domain |
| Description: |
Potassium channels are the most diverse group of the ion channel family [, ]. They are important in shaping the action potential, and in neuronal excitability and plasticity []. The potassium channel family is composed of several functionally distinct isoforms, which can be broadly separated into 2 groups []: the practically non-inactivating 'delayed' group and the rapidly inactivating 'transient' group.These are all highly similar proteins, with only small amino acid changes causing the diversity of the voltage-dependent gating mechanism, channel conductance and toxin binding properties. Each type of K+channel is activated by different signals and conditions depending on their type of regulation: some open in response to depolarisation of the plasma membrane; others in response to hyperpolarisation or an increase in intracellular calcium concentration; some can be regulated by binding of a transmitter, together with intracellular kinases; while others are regulated by GTP-binding proteins or other second messengers []. In eukaryotic cells, K+channels are involved in neural signalling and generation of the cardiac rhythm, act as effectors in signal transduction pathways involving G protein-coupled receptors (GPCRs) and may have a role in target cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in the maintenance of ionic homeostasis [].All K+channels discovered so far possess a core of alpha subunits, each comprising either one or two copies of a highly conserved pore loop domain (P-domain). The P-domain contains the sequence (T/SxxTxGxG), which has been termed the K+selectivity sequence. In families that contain one P-domain, four subunits assemble to form a selective pathway for K+across the membrane. However, it remains unclear how the 2 P-domain subunits assemble to form a selective pore. The functional diversity of these families can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. K+channel subunits containing one pore domain can be assigned into one of two superfamilies: those that possess six transmembrane (TM) domains and those that possess only two TM domains. The six TM domain superfamily can be further subdivided into conserved gene families: the voltage-gated (Kv) channels; the KCNQ channels (originally known as KvLQT channels); the EAG-like K+channels; and three types of calcium (Ca)-activated K+channels (BK, IK and SK) []. The 2TM domain family comprises inward-rectifying K+channels. In addition, there areK+channel alpha-subunits that possess two P-domains. These are usually highly regulated K+selective leak channels.KCNQ channels (also known as KQT-like channels) differ from other voltage-gated 6 TM helix channels, chiefly in that they possess no tetramerisation domain. Consequently, they rely on interaction with accessory subunits, or form heterotetramers with other members of the family []. Currently, 5 members of the KCNQ family are known. These have been found to be widely distributed within the body, having been shown to be expressed in the heart, brain, pancreas, lung, placenta and ear. They were initially cloned as a result of a search for proteins involved in cardiac arhythmia. Subsequently, mutations in other KCNQ family members have been shown to be responsible for some forms of hereditary deafness []and benign familial neonatal epilepsy [].This entry represents a region found at the C terminus of these proteins. |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
398
 |
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
405
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
103
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
129
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
933
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
426
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
123
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
422
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
113
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
952
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
405
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
103
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
129
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
430
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
538
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
152
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
241
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
924
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
66
|
| Fragment?: |
true |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
440
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
453
|
| Fragment?: |
true |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
521
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
440
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
398
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
237
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
413
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
241
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
823
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
414
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
535
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
123
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Vergara C |
| Year: |
1998 |
| Journal: |
Curr Opin Neurobiol |
| Title: |
Calcium-activated potassium channels. |
| Volume: |
8 |
| Issue: |
3 |
| Pages: |
321-9 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Schroeder BC |
| Year: |
1998 |
| Journal: |
Nature |
| Title: |
Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy. |
| Volume: |
396 |
| Issue: |
6712 |
| Pages: |
687-90 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Doupnik CA |
| Year: |
1995 |
| Journal: |
Curr Opin Neurobiol |
| Title: |
The inward rectifier potassium channel family. |
| Volume: |
5 |
| Issue: |
3 |
| Pages: |
268-77 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Minor DL Jr |
| Year: |
1999 |
| Journal: |
Cell |
| Title: |
Transmembrane structure of an inwardly rectifying potassium channel. |
| Volume: |
96 |
| Issue: |
6 |
| Pages: |
879-91 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Reimann F |
| Year: |
1999 |
| Journal: |
Curr Opin Cell Biol |
| Title: |
Inwardly rectifying potassium channels. |
| Volume: |
11 |
| Issue: |
4 |
| Pages: |
503-8 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Littleton JT |
| Year: |
2000 |
| Journal: |
Neuron |
| Title: |
Ion channels and synaptic organization: analysis of the Drosophila genome. |
| Volume: |
26 |
| Issue: |
1 |
| Pages: |
35-43 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Levitan ES |
| Year: |
2000 |
| Journal: |
Trends Cardiovasc Med |
| Title: |
Surface expression of Kv1 voltage-gated K+ channels is governed by a C-terminal motif. |
| Volume: |
10 |
| Issue: |
7 |
| Pages: |
317-20 |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
654
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Sanguinetti MC |
| Year: |
2000 |
| Journal: |
Trends Pharmacol Sci |
| Title: |
Maximal function of minimal K+ channel subunits. |
| Volume: |
21 |
| Issue: |
6 |
| Pages: |
199-201 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Wang Q |
| Year: |
1996 |
| Journal: |
Nat Genet |
| Title: |
Positional cloning of a novel potassium channel gene: KVLQT1 mutations cause cardiac arrhythmias. |
| Volume: |
12 |
| Issue: |
1 |
| Pages: |
17-23 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Biervert C |
| Year: |
1998 |
| Journal: |
Science |
| Title: |
A potassium channel mutation in neonatal human epilepsy. |
| Volume: |
279 |
| Issue: |
5349 |
| Pages: |
403-6 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Birnbaum SG |
| Year: |
2004 |
| Journal: |
Physiol Rev |
| Title: |
Structure and function of Kv4-family transient potassium channels. |
| Volume: |
84 |
| Issue: |
3 |
| Pages: |
803-33 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Bähring R |
| Year: |
2001 |
| Journal: |
J Biol Chem |
| Title: |
Coupling of voltage-dependent potassium channel inactivation and oxidoreductase active site of Kvbeta subunits. |
| Volume: |
276 |
| Issue: |
25 |
| Pages: |
22923-9 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Salinas M |
| Year: |
1997 |
| Journal: |
J Biol Chem |
| Title: |
New modulatory alpha subunits for mammalian Shab K+ channels. |
| Volume: |
272 |
| Issue: |
39 |
| Pages: |
24371-9 |
|
•
•
•
•
•
|
| Publication |
| First Author: |
Sansom MS |
| Year: |
2000 |
| Journal: |
Curr Biol |
| Title: |
Potassium channels: watching a voltage-sensor tilt and twist. |
| Volume: |
10 |
| Issue: |
5 |
| Pages: |
R206-9 |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
367
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
499
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
873
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
501
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
495
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
393
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
336
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
424
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
379
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
375
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
425
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
401
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
445
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
528
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
372
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
602
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
529
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
857
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
907
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
511
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
419
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
249
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
390
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
402
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
179
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
402
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
353
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
425
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
393
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
392
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
103
|
| Fragment?: |
true |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
479
|
| Fragment?: |
false |
|
•
•
•
•
•
|
| Protein |
| Organism: |
Mus musculus/domesticus |
| Length: |
795
|
| Fragment?: |
true |
|
•
•
•
•
•
|
