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Protein Domain : IPR003950

Name  Potassium channel, voltage-dependent, ELK Short Name  K_chnl_volt-dep_ELK
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 [].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 [].

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
IPR013655 PAS fold-3 PAS_fold_3 Domain

1 Cross References

Identifier
Source . Name

Subject . Primary Identifier
PR01465 PRINTS IPR003950

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

3 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

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

6 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0085981 A1ZB14 Drosophila melanogaster
FBpp0277725 Q290R8 Drosophila pseudoobscura
FBpp0169459 B4KNK1 Drosophila mojavensis
FBpp0234612 B4LJZ2 Drosophila virilis
FBpp0256921 B4P513 Drosophila yakuba
Q23974_DROME Q23974 Drosophila melanogaster