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Protein Domain : IPR003971

Name  Potassium channel, voltage dependent, Kv9 Short Name  K_chnl_volt-dep_Kv9
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 iscomposed of several functionally distinct isoforms, which can be broadlyseparated 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 acidchanges 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 orother second messengers []. In eukaryotic cells, K+channelsare 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 intarget cell lysis by cytotoxic T-lymphocytes []. In prokaryotic cells, they play a role in themaintenance 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 hasbeen 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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Publication Counts Displayer

0 Child Features

1 Contains

DB identifier Name Short Name Type
IPR003131 Potassium channel tetramerisation-type BTB domain T1-type_BTB Domain

1 Cross References

Identifier
Source . Name
Subject . Primary Identifier
PR01494 PRINTS IPR003971

3 Data Sets

Name URL
TrEMBL data set http://www.ebi.ac.uk/trembl/
InterPro data set  
InterPro GO Annotation data set  

0 Found In

3 GO Annotation


Subject . Secondary Identifier
Subject . Name
Subject . Symbol
Ontology Term . Identifier
Ontology Term . Name
Potassium channel, voltage dependent, Kv9   GO:0005249 voltage-gated potassium channel activity
Potassium channel, voltage dependent, Kv9   GO:0006813 potassium ion transport
Potassium channel, voltage dependent, Kv9   GO:0008076 voltage-gated potassium channel complex

3 Ontology Annotations


Subject . Secondary Identifier
Subject . Name
Subject . Symbol
Ontology Term . Identifier
Ontology Term . Name
Potassium channel, voltage dependent, Kv9   GO:0005249 voltage-gated potassium channel activity
Potassium channel, voltage dependent, Kv9   GO:0006813 potassium ion transport
Potassium channel, voltage dependent, Kv9   GO:0008076 voltage-gated potassium channel complex

1 Parent Features

DB identifier Name Short Name Type
IPR003968 Potassium channel, voltage dependent, Kv K_chnl_volt-dep_Kv Family

65 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0293736 M9PE38 Drosophila melanogaster
FBpp0293739 M9ND32 Drosophila melanogaster
FBpp0293738 M9NFJ6 Drosophila melanogaster
FBpp0293735 M9MRU9 Drosophila melanogaster
FBpp0293733 Q0E8I8 Drosophila melanogaster
FBpp0293737 A8JNI9 Drosophila melanogaster
FBpp0306030 M9MRZ7 Drosophila melanogaster
FBpp0286851 B5DRF9 Drosophila pseudoobscura
FBpp0160621 B4KX09 Drosophila mojavensis
FBpp0228016 B4LE37 Drosophila virilis
FBpp0265354 B4PCX7 Drosophila yakuba
A8XPS0_CAEBR A8XPS0 Caenorhabditis briggsae
A8X9J4_CAEBR A8X9J4 Caenorhabditis briggsae
A8XBM0_CAEBR A8XBM0 Caenorhabditis briggsae
A8XV67_CAEBR A8XV67 Caenorhabditis briggsae
A8XS70_CAEBR A8XS70 Caenorhabditis briggsae
A8X8J1_CAEBR A8X8J1 Caenorhabditis briggsae
K7H5Y1_CAEJA K7H5Y1 Caenorhabditis japonica
H2VX12_CAEJA H2VX12 Caenorhabditis japonica
H2W912_CAEJA H2W912 Caenorhabditis japonica
H2WF21_CAEJA H2WF21 Caenorhabditis japonica
G0NTV3_CAEBE G0NTV3 Caenorhabditis brenneri
G0MXQ0_CAEBE G0MXQ0 Caenorhabditis brenneri
G0MWJ7_CAEBE G0MWJ7 Caenorhabditis brenneri
G0P7Z7_CAEBE G0P7Z7 Caenorhabditis brenneri
G0P7Z4_CAEBE G0P7Z4 Caenorhabditis brenneri
G0P7Z5_CAEBE G0P7Z5 Caenorhabditis brenneri
G0N8Q8_CAEBE G0N8Q8 Caenorhabditis brenneri
G0PKZ7_CAEBE G0PKZ7 Caenorhabditis brenneri
G0ML84_CAEBE G0ML84 Caenorhabditis brenneri




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