KvLQT1

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Potassium voltage-gated channel, KQT-like subfamily, member 1
Identifiers
Symbol(s) KCNQ1; KCNA8; ATFB1; FLJ26167; JLNS1; KCNA9; KVLQT1; Kv1.9; Kv7.1; LQT; LQT1; RWS; SQT2; WRS
External IDs OMIM: 607542 MGI108083 HomoloGene85014
RNA expression pattern

More reference expression data

Orthologs
Human Mouse
Entrez 3784 16535
Ensembl ENSG00000053918 ENSMUSG00000009545
Uniprot P51787 Q3U4H1
Refseq NM_181797 (mRNA)
NP_861462 (protein)
XM_622938 (mRNA)
XP_622938 (protein)
Location Chr 11: 2.42 - 2.83 Mb Chr 7: 142.92 - 143.24 Mb
Pubmed search [1] [2]

KvLQT1 (Kv7.1) is a potassium channel protein coded for by the gene KCNQ1.[1] KvLQT1 is present in the cell membranes of cardiac muscle tissue and in inner ear neurons among other tissues. In the cardiac cells, KvLQT1 mediates the IKs (or slow delayed rectifying K+) current that contributes to the repolarization of the cell, terminating the cardiac action potential and thereby the heart's contraction.

Mutations in the gene can lead to a defective protein and several forms of inherited arrhythmias as Long QT syndrome, Short QT syndrome, and Familial Atrial Fibrillation. Currents arising from KvLQT1 in over-expression systems have never been recapitulated in native tissues - KvLQT1 is always found in native tissues with a modulatory subunit. In cardiac tissue, these subunits comprise KCNE1 and yotiao. Though physiologically irrelevant, homotetrameric KvLQT1 channels also display a unique form of N-type inactivation that reaches quilibrium quickly, allowing KvLQT1 currents to plateau. This is different from the inactivation seen in A-type currents, in which most of the current never returns.

This gene encodes a protein for a voltage-gated potassium channel required for the repolarization phase of the cardiac action potential. The gene product can form heteromultimers with two other potassium channel proteins, KCNE1 and KCNE3. Mutations in this gene are associated with hereditary long QT syndrome, Romano-Ward syndrome, Jervell and Lange-Nielsen syndrome and familial atrial fibrillation. The gene is located in a region of chromosome 11 that contains a large number of contiguous genes that are abnormally imprinted in cancer and the Beckwith-Wiedemann syndrome. Two alternative transcripts encoding distinct isoforms have been described.[2]

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[edit] References

  1. ^ Jespersen T, Grunnet M, Olesen SP (2005). "The KCNQ1 potassium channel: from gene to physiological function". Physiology (Bethesda) 20: 408–16. doi:10.1152/physiol.00031.2005. PMID 16287990. 
  2. ^ Entrez Gene: KCNQ1 potassium voltage-gated channel, KQT-like subfamily, member 1.

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