CACNA1S

This gene encodes one of the five subunits of the slowly inactivating L-type voltage-dependent calcium channel in skeletal muscle cells. Mutations in this gene have been associated with hypokalemic periodic paralysis, thyrotoxic periodic paralysis and malignant hyperthermia susceptibility. [provided by RefSeq]

calcium channel, voltage-dependent, L type, alpha 1S subunit

Pore-forming, alpha-1S subunit of the voltage-gated calcium channel that gives rise to L-type calcium currents in skeletal muscle. Calcium channels containing the alpha-1S subunit play an important role in excitation-contraction coupling in skeletal muscle via their interaction with RYR1, which triggers Ca2+ release from the sarcplasmic reticulum and ultimately results in muscle contraction. Long-lasting (L-type) calcium channels belong to the 'high-voltage activated' (HVA) group.

Calcium ion import Source: GO_Central
Calcium ion transport Source: UniProtKB
Cellular response to caffeine Source: UniProtKB
Muscle contraction Source: UniProtKB
Regulation of ion transmembrane transport Source: UniProtKB-KW

T-tubule

Periodic paralysis hypokalemic 1 (HOKPP1): An autosomal dominant disorder manifested by episodic flaccid generalized muscle weakness associated with falls of serum potassium levels.
Malignant hyperthermia 5 (MHS5): Autosomal dominant disorder that is potentially lethal in susceptible individuals on exposure to commonly used inhalational anesthetics and depolarizing muscle relaxants.
Thyrotoxic periodic paralysis 1 (TTPP1): A sporadic muscular disorder characterized by episodic weakness and hypokalemia during a thyrotoxic state. It is clinically similar to hereditary hypokalemic periodic paralysis, except for the fact that hyperthyroidism is an absolute requirement for disease manifestation. The disease presents with recurrent episodes of acute muscular weakness of the four extremities that vary in severity from paresis to complete paralysis. Attacks are triggered by ingestion of a high carbohydrate load or strenuous physical activity followed by a period of rest. Thyrotoxic periodic paralysis can occur in association with any cause of hyperthyroidism, but is most commonly associated with Graves disease.

Cytoplasmic: 1-51 aa
Helical: 52-70 aa
Extracellular: 71-85 aa
Helical: 86-106 aa
Cytoplasmic: 107-115 aa
Helical: 116-136 aa
Extracellular: 137-160 aa
Helical: 161-179 aa
Cytoplasmic: 180-196 aa
Helical: 197-218 aa
Extracellular: 219-279 aa
Pore-forming: 280-301 aa
Extracellular: 302-309 aa
Helical: 310-330 aa
Cytoplasmic: 331-432 aa
Helical: 433-451 aa
Extracellular: 452-462 aa
Helical: 463-483 aa
Cytoplasmic: 484-494 aa
Helical: 495-514 aa
Extracellular: 515-523 aa
Helical: 524-542 aa
Cytoplasmic: 543-561 aa
Helical: 562-581 aa
Extracellular: 582-601 aa
Pore-forming: 602-623 aa
Extracellular: 624-633 aa
Helical: 634-653 aa
Cytoplasmic: 654-799 aa
Helical: 800-818 aa
Extracellular: 819-830 aa
Helical: 831-850 aa
Cytoplasmic: 851-866 aa
Helical: 867-885 aa
Extracellular: 886-892 aa
Helical: 893-911 aa
Cytoplasmic: 912-930 aa
Helical: 931-950 aa
Extracellular: 951-1000 aa
Pore-forming: 1001-1021 aa
Extracellular: 1022-1038 aa
Helical: 1039-1060 aa
Cytoplasmic: 1061-1118 aa
Helical: 1119-1140 aa
Extracellular: 1141-1148 aa
Helical: 1149-1170 aa
Cytoplasmic: 1171-1180 aa
Helical: 1181-1200 aa
Extracellular: 1201-1231 aa
Helical: 1232-1250 aa
Cytoplasmic: 1251-1268 aa
Helical: 1269-1289 aa
Extracellular: 1290-1311 aa
Pore-forming: 1312-1330 aa
Extracellular: 1331-1356 aa
Helical: 1357-1381 aa
Cytoplasmic: 1382-1873 aa

The alpha-1S subunit is found in two isoforms in the skeletal muscle: a minor form of 212 kDa containing the complete amino acid sequence, and a major form of 190 kDa derived from the full-length form by post-translational proteolysis close to Phe-1690.By similarity
Phosphorylated. Phosphorylation by PKA activates the calcium channel. Both the minor and major forms are phosphorylated in vitro by PKA. Phosphorylation at Ser-1575 is involved in beta-adrenergic-mediated regulation of the channel.By similarity