Human Gene KCNJ1 (uc001qeo.2) Description and Page Index
Description: Homo sapiens potassium inwardly-rectifying channel, subfamily J, member 1 (KCNJ1), transcript variant 1, mRNA. RefSeq Summary (NM_000220): Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. It is activated by internal ATP and probably plays an important role in potassium homeostasis. The encoded protein has a greater tendency to allow potassium to flow into a cell rather than out of a cell. Mutations in this gene have been associated with antenatal Bartter syndrome, which is characterized by salt wasting, hypokalemic alkalosis, hypercalciuria, and low blood pressure. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]. Transcript (Including UTRs) Position: hg19 chr11:128,707,909-128,712,429 Size: 4,521 Total Exon Count: 2 Strand: - Coding Region Position: hg19 chr11:128,709,020-128,712,312 Size: 3,293 Coding Exon Count: 2
ID:IRK1_HUMAN DESCRIPTION: RecName: Full=ATP-sensitive inward rectifier potassium channel 1; AltName: Full=ATP-regulated potassium channel ROM-K; AltName: Full=Inward rectifier K(+) channel Kir1.1; AltName: Full=Potassium channel, inwardly rectifying subfamily J member 1; FUNCTION: In the kidney, probably plays a major role in potassium homeostasis. Inward rectifier potassium channels are characterized by a greater tendency to allow potassium to flow into the cell rather than out of it. Their voltage dependence is regulated by the concentration of extracellular potassium; as external potassium is raised, the voltage range of the channel opening shifts to more positive voltages. The inward rectification is mainly due to the blockage of outward current by internal magnesium. This channel is activated by internal ATP and can be blocked by external barium. ENZYME REGULATION: Inhibited by WNK3. SUBUNIT: Interacts with SGK1 and SLC9A3R2/NHERF2. SUBCELLULAR LOCATION: Cell membrane; Multi-pass membrane protein. Note=Phosphorylation at Ser-44 by SGK1 is necessary for its expression at the cell membrane. TISSUE SPECIFICITY: In the kidney and pancreatic islets. Lower levels in skeletal muscle, pancreas, spleen, brain, heart and liver. PTM: Phosphorylation at Ser-44 by SGK1 is necessary for its expression at the cell membrane. DISEASE: Defects in KCNJ1 are the cause of Bartter syndrome type 2 (BS2) [MIM:241200]; also termed hyperprostanglandin E syndrome 2. BS refers to a group of autosomal recessive disorders characterized by impaired salt reabsorption in the thick ascending loop of Henle with pronounced salt wasting, hypokalemic metabolic alkalosis, and varying degrees of hypercalciuria. BS2 is a life- threatening condition beginning in utero, with marked fetal polyuria that leads to polyhydramnios and premature delivery. Another hallmark of BS2 is a marked hypercalciuria and, as a secondary consequence, the development of nephrocalcinosis and osteopenia. SIMILARITY: Belongs to the inward rectifier-type potassium channel (TC 1.A.2.1) family. KCNJ1 subfamily. WEB RESOURCE: Name=GeneReviews; URL="http://www.ncbi.nlm.nih.gov/sites/GeneTests/lab/gene/KCNJ1";
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.
SCOP Domains: 81296 - E set domains 81324 - Voltage-gated potassium channels
ModBase Predicted Comparative 3D Structure on P48048
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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.