Biology:KCNA2

Short description: Protein-coding gene in the species Homo sapiens

Generic protein structure example

Potassium voltage-gated channel subfamily A member 2 also known as K_v1.2 is a protein that in humans is encoded by the KCNA2 gene.

Function

Potassium channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shaker-related subfamily. This member contains six membrane-spanning domains with a shaker-type repeat in the fourth segment. It belongs to the delayed rectifier class, members of which allow nerve cells to efficiently repolarize following an action potential. The coding region of this gene is intronless, and the gene is clustered with genes KCNA3 and KCNA10 on chromosome 1.

Interactions

KCNA2 has been shown to interact with KCNA4, DLG4, PTPRA, KCNAB2, RHOA and Cortactin.

Clinical

Mutations in this gene have been associated with hereditary spastic paraplegia.

See also

• Voltage-gated potassium channel
• Pandinotoxin

Further reading

• "Cloning and expression of a rat cardiac delayed rectifier potassium channel". Proceedings of the National Academy of Sciences of the United States of America 88 (17): 7892–5. September 1991. doi:10.1073/pnas.88.17.7892. PMID 1715584. Bibcode: 1991PNAS...88.7892P. 
• "Expression and chromosomal localization of a lymphocyte K+ channel gene". Proceedings of the National Academy of Sciences of the United States of America 87 (23): 9411–5. December 1990. doi:10.1073/pnas.87.23.9411. PMID 2251283. Bibcode: 1990PNAS...87.9411G. 
• "Isolation of a cDNA clone coding for a putative second potassium channel indicates the existence of a gene family". The Journal of Biological Chemistry 264 (14): 8230–6. May 1989. doi:10.1016/S0021-9258(18)83173-8. PMID 2722779. 
• "Clustering of Shaker-type K+ channels by interaction with a family of membrane-associated guanylate kinases". Nature 378 (6552): 85–8. November 1995. doi:10.1038/378085a0. PMID 7477295. Bibcode: 1995Natur.378...85K. 
• "Chromosomal mapping in the mouse of eight K(+)-channel genes representing the four Shaker-like subfamilies Shaker, Shab, Shaw, and Shal". Genomics 18 (3): 568–74. December 1993. doi:10.1016/S0888-7543(05)80358-1. PMID 7905852. 
• "Facile formation of heteromultimeric potassium channels by expression of cloned human cDNAs". Indian Journal of Biochemistry & Biophysics 31 (4): 254–60. August 1994. PMID 8002006. 
• "Selective interaction of voltage-gated K+ channel beta-subunits with alpha-subunits". The Journal of Biological Chemistry 271 (12): 7084–9. March 1996. doi:10.1074/jbc.271.12.7084. PMID 8636142. 
• "Expression and function of voltage-dependent potassium channel genes in human airway smooth muscle". The Journal of Biological Chemistry 271 (22): 13239–43. May 1996. doi:10.1074/jbc.271.22.13239. PMID 8662756. 
• "Normalization and subtraction: two approaches to facilitate gene discovery". Genome Research 6 (9): 791–806. September 1996. doi:10.1101/gr.6.9.791. PMID 8889548. 
• "Differential K+ channel clustering activity of PSD-95 and SAP97, two related membrane-associated putative guanylate kinases". Neuropharmacology 35 (7): 993–1000. 1997. doi:10.1016/0028-3908(96)00093-7. PMID 8938729. 
• "The small GTP-binding protein RhoA regulates a delayed rectifier potassium channel". Cell 93 (6): 1077–85. June 1998. doi:10.1016/S0092-8674(00)81212-X. PMID 9635436. 
• "Receptor protein tyrosine phosphatase alpha participates in the m1 muscarinic acetylcholine receptor-dependent regulation of Kv1.2 channel activity". The EMBO Journal 18 (1): 109–18. January 1999. doi:10.1093/emboj/18.1.109. PMID 9878055. 
• "Subunit composition of Kv1 channels in human CNS". Journal of Neurochemistry 73 (2): 849–58. August 1999. doi:10.1046/j.1471-4159.1999.0730849.x. PMID 10428084. 
• "Mutations in the KCNA1 gene associated with episodic ataxia type-1 syndrome impair heteromeric voltage-gated K(+) channel function". FASEB Journal 13 (11): 1335–45. August 1999. doi:10.1096/fasebj.13.11.1335. PMID 10428758. 
• "Delayed rectifier and Ca(2+)-dependent K(+) currents in human esophagus: roles in regulating muscle contraction". The American Journal of Physiology 277 (4 Pt 1): G885–95. October 1999. doi:10.1152/ajpgi.1999.277.4.g885. PMID 10516156. 
• "Caspr2, a new member of the neurexin superfamily, is localized at the juxtaparanodes of myelinated axons and associates with K+ channels". Neuron 24 (4): 1037–47. December 1999. doi:10.1016/S0896-6273(00)81049-1. PMID 10624965. 
• "Subunit composition determines Kv1 potassium channel surface expression". The Journal of Biological Chemistry 275 (38): 29685–93. September 2000. doi:10.1074/jbc.M005010200. PMID 10896669. 
• "KChAP/Kvbeta1.2 interactions and their effects on cardiac Kv channel expression". American Journal of Physiology. Cell Physiology 281 (1): C290–9. July 2001. doi:10.1152/ajpcell.2001.281.1.c290. PMID 11401852. 
• "Signal transduction of physiological concentrations of vasopressin in A7r5 vascular smooth muscle cells. A role for PYK2 and tyrosine phosphorylation of K+ channels in the stimulation of Ca2+ spiking". The Journal of Biological Chemistry 277 (9): 7298–307. March 2002. doi:10.1074/jbc.M104726200. PMID 11739373. 

External links

• Kv1.2+Potassium+Channel at the US National Library of Medicine Medical Subject Headings (MeSH)
• KCNA2+protein,+human at the US National Library of Medicine Medical Subject Headings (MeSH)

This article incorporates text from the United States National Library of Medicine, which is in the public domain.