Summary: Polycystin cation channel
Polycystin cation channel Provide feedback
This family contains the cation channel region of PKD1 and PKD2 proteins.
Chen XZ, Vassilev PM, Basora N, Peng JB, Nomura H, Segal Y, Brown EM, Reeders ST, Hediger MA, Zhou J; , Nature 1999;401:383-386.: Polycystin-L is a calcium-regulated cation channel permeable to calcium ions. PUBMED:10517637 EPMC:10517637
Vassilev PM, Guo L, Chen XZ, Segal Y, Peng JB, Basora N, Babakhanlou H, Cruger G, Kanazirska M, Ye Cp, Brown EM, Hediger MA, Zhou J; , Biochem Biophys Res Commun 2001;282:341-350.: Polycystin-2 is a novel cation channel implicated in defective intracellular Ca(2+) homeostasis in polycystic kidney disease. PUBMED:11264013 EPMC:11264013
Internal database links
|Similarity to PfamA using HHSearch:||Ion_trans|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR013122
Polycystic kidney diseases (PKD) are disorders characterised by large numbers of cysts distributed throughout grossly-enlarged kidneys. Cyst development is associated with impairment of kidney function, and ultimately kidney failure and death [PUBMED:8643665]. Most cases of autosomal dominant PKD result from mutations in the PKD1 gene that cause premature protein termination.
A second gene for autosomal dominant polycystic kidney disease has been identified by positional cloning [PUBMED:8650545]. The predicted 968-amino acid sequence of the PKD2 gene product (polycystin-2) contains 6 transmembrane domains, with intracellular N- and C-termini. Polycystin-2 shares some similarity with the family of voltage-activated calcium (and sodium) channels, and contains a potential calcium-binding domain.
Polycystin-2 is strongly expressed in ovary, foetal and adult kidney, testis, and small intestine. Polycystin-1 requires the presence of this protein for stable expression and is believed to interact with it via its C terminus. All mutations between exons 1 and 11 result in a truncated polycystin-2 that lacks a calcium-binding EF-hand domain and the cytoplasmic domains required for the interaction of polycystin-2 with polycystin-1 [PUBMED:9326320]. PKD2, although clinically milder than PKD1, has a deleterious impact on life expectancy.
This entry contains proteins belonging to the polycystin family including Mucolipin and Polycystin-1 and -2 (PKD1 and PKD2). The domain contains the cation channel region of PKD1 and PKD2 proteins. PKD1 and PKD2 may function through a common signalling pathway that is necessary for normal tubulogenesis. The PKD2 gene product has six transmembrane spans with intracellular amino- and carboxyl-termini [PUBMED:8650545].
Mucolipin is a cationic channel which probably plays a role in the endocytic pathway and in the control of membrane trafficking of proteins and lipids. It could play a major role in the calcium ion transport regulating lysosomal exocytosis [PUBMED:11013137, PUBMED:12459486, PUBMED:14749347].
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This superfamily contains a diverse range of ion channels that share a pair of transmembrane helices in common. This clan is classified as the VIC (Voltage-gated Ion Channel) superfamily in TCDB.
The clan contains the following 7 members:Ion_trans Ion_trans_2 IRK KdpA Lig_chan PKD_channel TrkH
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Curation and family details
|Seed source:||Bateman A|
|Number in seed:||12|
|Number in full:||2051|
|Average length of the domain:||264.50 aa|
|Average identity of full alignment:||17 %|
|Average coverage of the sequence by the domain:||26.95 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||8|
|Download:||download the raw HMM for this family|
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