Nav1.1
Encyclopedia
Nav1.1, also known as the sodium channel, voltage-gated, type I, alpha subunit (SCN1A), is a protein
which in humans is encoded by the SCN1A gene
.
essential for the generation and propagation of action potential
s, chiefly in nerve and muscle. Voltage-sensitive sodium channels are heteromeric complexes consisting of a large central pore-forming glycosylated alpha subunit and 2 smaller auxiliary beta subunits. Functional studies have indicated that the transmembrane alpha subunit of the brain sodium channels is sufficient for expression of functional sodium channels. Brain sodium channel alpha subunits form a gene subfamily with several structurally distinct isoforms clustering on chromosome 2q24, types I, II (Nav1.2
), and III (Nav1.3
). There are also several distinct sodium channel alpha subunit isoforms in skeletal and cardiac muscle (Nav1.4 and Nav1.5, respectively).
s and GEFS+, type 2.
, Australia
have told journalists that they would test 50% more infants for the gene, if they could conduct the test on site.
with syntrophin, alpha 1.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
which in humans is encoded by the SCN1A gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
The vertebrate sodium channel is a voltage-gated ion channelVoltage-gated ion channel
Voltage-gated ion channels are a class of transmembrane ion channels that are activated by changes in electrical potential difference near the channel; these types of ion channels are especially critical in neurons, but are common in many types of cells....
essential for the generation and propagation of action potential
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
s, chiefly in nerve and muscle. Voltage-sensitive sodium channels are heteromeric complexes consisting of a large central pore-forming glycosylated alpha subunit and 2 smaller auxiliary beta subunits. Functional studies have indicated that the transmembrane alpha subunit of the brain sodium channels is sufficient for expression of functional sodium channels. Brain sodium channel alpha subunits form a gene subfamily with several structurally distinct isoforms clustering on chromosome 2q24, types I, II (Nav1.2
Nav1.2
Navα1.2, also known as the sodium channel, voltage-gated, type II, alpha subunit is a protein that in humans is encoded by the SCN2A gene. Functional sodium channels contain an ion conductive alpha subunit and one or more regulatory beta subunits. Sodium channels which contain the Navα1.2 subunit...
), and III (Nav1.3
SCN3A
Sodium channel, voltage-gated, type III, alpha subunit is a protein that in humans is encoded by the Nav1.3 gene.- External links :...
). There are also several distinct sodium channel alpha subunit isoforms in skeletal and cardiac muscle (Nav1.4 and Nav1.5, respectively).
Clinical significance
Mutations in the SCNA1 gene cause inherited febrile seizureFebrile seizure
A febrile seizure, also known as a fever fit or febrile convulsion, is a convulsion associated with a significant rise in body temperature...
s and GEFS+, type 2.
Patent controversy
On November 29th 2008, The Sydney Morning Herald reported the first evidence of private intellectual property rights over human DNA having adversely affected medical care. The Melbourne company Genetic Technologies (GTG) controls rights to the gene, and requires royalties for tests on the gene, which can help identify Dravet syndrome. Doctors on the Children's Hospital in WestmeadWestmead
Westmead nay refer to:*Westmead, New South Wales, a city in Australia*USS Westmead , also spelled , a United States Navy cargo ship in commission from 1918 to 1919See also*West Mead...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
have told journalists that they would test 50% more infants for the gene, if they could conduct the test on site.
Interactions
Nav1.1 has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with syntrophin, alpha 1.