Human Gene KCNQ3 (uc003ytj.3) Description and Page Index
Description: Homo sapiens potassium voltage-gated channel, KQT-like subfamily, member 3 (KCNQ3), transcript variant 1, mRNA. RefSeq Summary (NM_004519): This gene encodes a protein that functions in the regulation of neuronal excitability. The encoded protein forms an M-channel by associating with the products of the related KCNQ2 or KCNQ5 genes, which both encode integral membrane proteins. M-channel currents are inhibited by M1 muscarinic acetylcholine receptors and are activated by retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of benign familial neonatal convulsions type 2 (BFNC2), also known as epilepsy, benign neonatal type 2 (EBN2). Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2014]. Transcript (Including UTRs) Position: hg19 chr8:133,133,105-133,493,004 Size: 359,900 Total Exon Count: 15 Strand: - Coding Region Position: hg19 chr8:133,141,509-133,492,779 Size: 351,271 Coding Exon Count: 15
ID:KCNQ3_HUMAN DESCRIPTION: RecName: Full=Potassium voltage-gated channel subfamily KQT member 3; AltName: Full=KQT-like 3; AltName: Full=Potassium channel subunit alpha KvLQT3; AltName: Full=Voltage-gated potassium channel subunit Kv7.3; FUNCTION: Probably important in the regulation of neuronal excitability. Associates with KCNQ2 or KCNQ5 to form a potassium channel with essentially identical properties to the channel underlying the native M-current, a slowly activating and deactivating potassium conductance which plays a critical role in determining the subthreshold electrical excitability of neurons as well as the responsiveness to synaptic inputs. SUBUNIT: Heteromultimer with KCNQ2 or KCNQ5. May associate with KCNE2. SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein. TISSUE SPECIFICITY: Predominantly expressed in brain. DOMAIN: The segment S4 is probably the voltage-sensor and is characterized by a series of positively charged amino acids at every third position (By similarity). DISEASE: Defects in KCNQ3 are the cause of benign familial neonatal seizures type 2 (BFNS2) [MIM:121201]. A disorder characterized by clusters of seizures occurring in the first days of life. Most patients have spontaneous remission by 12 months of age and show normal psychomotor development. The disorder is distinguished from benign familial infantile seizures by an earlier age at onset. MISCELLANEOUS: Mutagenesis experiments were carried out in Xenopus oocytes by coexpression of either KCNQ3(mut) and KCNQ2 at the ratio of 1:1, or of KCNQ3(mut), KCNQ3(wt) and KCNQ2 at the ratio of 1:1:2, to mimic the situation in a heterozygous patient with BFNC2 disease. SIMILARITY: Belongs to the potassium channel family. KQT (TC 1.A.1.15) subfamily. Kv7.3/KCNQ3 sub-subfamily. WEB RESOURCE: Name=GeneReviews; URL="http://www.ncbi.nlm.nih.gov/sites/GeneTests/lab/gene/KCNQ3";
Genetic Association Studies of Complex Diseases and Disorders
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on O43525
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.