Nav1.4: Difference between revisions

Latest revision as of 20:32, 30 December 2024

Nav1.4 is a voltage-gated sodium channel that is primarily expressed in skeletal muscle tissue. It is encoded by the SCN4A gene in humans. This channel plays a crucial role in the generation and propagation of action potentials in muscle cells, which are essential for muscle contraction.

Function[edit]

Nav1.4 channels are responsible for the rapid influx of sodium ions (Na⁺) into muscle cells, which depolarizes the cell membrane and initiates an action potential. This process is vital for the proper functioning of skeletal muscles, allowing for voluntary movement and reflexes.

Clinical Significance[edit]

Mutations in the SCN4A gene can lead to a variety of neuromuscular disorders. Some of these include:

These conditions are characterized by episodes of muscle weakness or stiffness, which can be triggered by factors such as exercise, temperature changes, or potassium levels.

Research and Therapeutic Implications[edit]

Understanding the function and regulation of Nav1.4 channels is important for developing treatments for the associated neuromuscular disorders. Research is ongoing to find pharmacological agents that can modulate the activity of these channels to alleviate symptoms in affected individuals.

References[edit]

External Links[edit]

[Nav1.4 at IUPHAR/BPS Guide to PHARMACOLOGY](https://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=528)
[SCN4A gene information at NCBI](https://www.ncbi.nlm.nih.gov/gene/6329)

Template:Voltage-gated sodium channels Template:Skeletal muscle

@@ Line 1: / Line 1: @@
-'''Nav1.4''' is a [[protein]] that in humans is encoded by the SCN4A [[gene]]. It is a [[voltage-gated sodium channel]] that plays a crucial role in the initiation and propagation of [[action potentials]] in skeletal muscle. Mutations in this gene have been associated with several [[myotonic disorders]] and [[periodic paralysis]] syndromes.
-==Structure==
+{{Infobox protein
-Nav1.4 is a large, complex protein composed of four homologous domains (I-IV), each containing six transmembrane segments (S1-S6). The S4 segment of each domain acts as the voltage sensor, while the pore-forming loop between S5 and S6 is responsible for sodium ion selectivity and conductance.
+| name = Nav1.4
+| image = <!-- Image removed -->
+| caption = <!-- Image caption removed -->
+| symbol = SCN4A
+| alt_symbols = <!-- Alternative symbols -->
+| EntrezGene = 6329
+| HGNCid = 10586
+| OMIM = 603967
+| RefSeq = NM_000334
+| UniProt = P35499
+| PDB = <!-- PDB ID -->
+}}
-==Function==
+'''Nav1.4''' is a [[voltage-gated sodium channel]] that is primarily expressed in [[skeletal muscle]] tissue. It is encoded by the [[SCN4A]] gene in humans. This channel plays a crucial role in the generation and propagation of [[action potentials]] in muscle cells, which are essential for muscle contraction.
-Nav1.4 is primarily expressed in [[skeletal muscle]], where it is responsible for the upstroke of the action potential. This rapid depolarization allows for the propagation of electrical signals along the muscle fiber, leading to muscle contraction.
-==Clinical significance==
+== Function ==
-Mutations in the SCN4A gene can lead to a variety of neuromuscular disorders. These include [[Hyperkalemic periodic paralysis]], [[Paramyotonia congenita]], and [[Potassium-aggravated myotonia]]. These conditions are characterized by episodes of muscle weakness or stiffness, often triggered by exercise, cold, or potassium intake.
+Nav1.4 channels are responsible for the rapid influx of [[sodium ions]] (Na⁺) into muscle cells, which depolarizes the cell membrane and initiates an action potential. This process is vital for the proper functioning of skeletal muscles, allowing for voluntary movement and reflexes.
-==See also==
+== Clinical Significance ==
-* [[Sodium channel]]
+Mutations in the SCN4A gene can lead to a variety of [[neuromuscular disorders]]. Some of these include:
-* [[Voltage-gated ion channel]]
-* [[Myotonia]]
-* [[Periodic paralysis]]
-==References==
+* [[Hyperkalemic periodic paralysis]]
-<references/>
+* [[Paramyotonia congenita]]
+* [[Potassium-aggravated myotonia]]
+* [[Congenital myasthenic syndrome]]
+These conditions are characterized by episodes of muscle weakness or stiffness, which can be triggered by factors such as exercise, temperature changes, or potassium levels.
+== Research and Therapeutic Implications ==
+Understanding the function and regulation of Nav1.4 channels is important for developing treatments for the associated neuromuscular disorders. Research is ongoing to find [[pharmacological agents]] that can modulate the activity of these channels to alleviate symptoms in affected individuals.
+== See Also ==
+* [[Voltage-gated sodium channel]]
+* [[Skeletal muscle]]
+* [[Action potential]]
+== References ==
+<references />
+== External Links ==
+* [Nav1.4 at IUPHAR/BPS Guide to PHARMACOLOGY](https://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=528)
+* [SCN4A gene information at NCBI](https://www.ncbi.nlm.nih.gov/gene/6329)
+{{Voltage-gated sodium channels}}
+{{Skeletal muscle}}
 [[Category:Ion channels]]
-[[Category:Membrane proteins]]
+[[Category:Skeletal muscle proteins]]
-[[Category:Voltage-gated ion channels]]
+[[Category:Neuromuscular disorders]]
-[[Category:Human proteins]]
-[[Category:Genes on human chromosome 17]]
-{{Ion channels}}
-{{Membrane transport proteins}}
-{{Human chromosome 17 gene stubs}}
-{{medicine-stub}}