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Protein Domain : IPR003949

Name  Potassium channel, voltage-dependent, EAG Short Name  K_chnl_volt-dep_EAG
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 in target 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 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 elegansappears to lack the ELK type [].The EAG subfamily has been expressed in heterologous systems to reveal their biophysical and pharmacological functions and to determine their currents in native tissues. All mammalian EAG subfamily K+ channels that have been identified have properties typical of delayed rectifiers, with no measurable inactivation []. Only the Drosophila melanogasterEag channel exhibits partial inactivation.

Publication Counts Displayer

0 Child Features

8 Contains

DB identifier Name Short Name Type
IPR014710 RmlC-like jelly roll fold RmlC-like_jellyroll Domain
IPR001610 PAC motif PAC Repeat
IPR000014 PAS domain PAS Domain
IPR018490 Cyclic nucleotide-binding-like cNMP-bd-like Domain
IPR000595 Cyclic nucleotide-binding domain cNMP-bd_dom Domain
IPR005821 Ion transport domain Ion_trans_dom Domain
IPR000700 PAS-associated, C-terminal PAS-assoc_C Domain
IPR013767 PAS fold PAS_fold Domain

1 Cross References

Identifier
Source . Name

Subject . Primary Identifier
PR01464 PRINTS IPR003949

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, EAG   GO:0005249 voltage-gated potassium channel activity
Potassium channel, voltage-dependent, EAG   GO:0006813 potassium ion transport
Potassium channel, voltage-dependent, EAG   GO:0016020 membrane

3 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
Potassium channel, voltage-dependent, EAG   GO:0005249 voltage-gated potassium channel activity
Potassium channel, voltage-dependent, EAG   GO:0006813 potassium ion transport
Potassium channel, voltage-dependent, EAG   GO:0016020 membrane

1 Parent Features

DB identifier Name Short Name Type
IPR003938 Potassium channel, voltage-dependent, EAG/ELK/ERG K_chnl_volt-dep_EAG/ELK/ERG Family

20 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0301718 M9PHT2 Drosophila melanogaster
FBpp0301717 M9PH56 Drosophila melanogaster
FBpp0301719 M9PHM3 Drosophila melanogaster
FBpp0073772 Q02280 Drosophila melanogaster
FBpp0292377 M9MSD1 Drosophila melanogaster
FBpp0292378 M9MSA6 Drosophila melanogaster
FBpp0110308 Q0KHS8 Drosophila melanogaster
FBpp0273494 B5DLA7 Drosophila pseudoobscura
FBpp0164423 B4L255 Drosophila mojavensis
FBpp0231033 B4M8E5 Drosophila virilis
FBpp0262168 B4PW93 Drosophila yakuba
A8X2Q3_CAEBR A8X2Q3 Caenorhabditis briggsae
K7IGJ2_CAEJA K7IGJ2 Caenorhabditis japonica
H2VJL3_CAEJA H2VJL3 Caenorhabditis japonica
G0M8U7_CAEBE G0M8U7 Caenorhabditis brenneri
O44164_CAEEL O44164 Caenorhabditis elegans
Q9XYX7_CAEEL Q9XYX7 Caenorhabditis elegans
C7LAD4_DROME C7LAD4 Drosophila melanogaster
Q1EC37_DROME Q1EC37 Drosophila melanogaster
E3LKB4_CAERE E3LKB4 Caenorhabditis remanei