Sodium channel protein type 2 subunit alpha, is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''SCN2A''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Functional
sodium channel
Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell (biology), cell's cell membrane, membrane. They belong to the Cation channel superfamily, superfamily of cation channels.
Classific ...
s contain an ion conductive alpha subunit and one or more regulatory beta subunits. Sodium channels which contain sodium channel protein type 2 subunit alpha are sometimes called Na
v1.2 channels.
Function
Voltage-gated sodium channel
Voltage-gated sodium channels (VGSCs), also known as voltage-dependent sodium channels (VDSCs), are a group of voltage-gated ion channels found in the membrane of excitable cells (''e.g.'', muscle, glial cells, neurons, etc.) with a permeability t ...
s are transmembrane
glycoprotein
Glycoproteins are proteins which contain oligosaccharide (sugar) chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known a ...
complexes composed of a large alpha subunit with four domains including 24 transmembrane segments and one or more regulatory beta subunits. They are responsible for the generation and propagation of
action potential
An action potential (also known as a nerve impulse or "spike" when in a neuron) is a series of quick changes in voltage across a cell membrane. An action potential occurs when the membrane potential of a specific Cell (biology), cell rapidly ri ...
s in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family. It is heterogeneously expressed in the brain, and mutations in this gene have been linked to several
seizure
A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, o ...
disorders. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined.
Clinical significance
Mutations in this gene have been implicated in cases of
autism
Autism, also known as autism spectrum disorder (ASD), is a neurodevelopmental disorder characterized by differences or difficulties in social communication and interaction, a preference for predictability and routine, sensory processing d ...
,
s, bitemporal glucose hypometabolism,
and
bipolar disorder
Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of Depression (mood), depression and periods of abnormally elevated Mood (psychology), mood that each last from days to weeks, and in ...
.
See also
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''paralytic'' - SCN2A ortholog in ''Drosophila''
References
Further reading
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External links
Patient organizations
The SCN2A FoundationFamilieSCN2A FoundationSCN2A Asia Pacific
SCN2A Germany e. V.
Other links
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Sodium channels
{{membrane-protein-stub