CACNA1A Antibody – Rabbit Polyclonal

Voltage-dependent calcium channels mediate the entry of calcium ions into excitable cells, and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, and gene expression. Calcium channels are multisubunit complexes composed of alpha-1, beta, alpha-2/delta, and gamma subunits. The channel activity is directed by the pore-forming alpha-1 subunit, whereas, the others act as auxiliary subunits regulating this activity. The distinctive properties of the calcium channel types are related primarily to the expression of a variety of alpha-1 isoforms, alpha-1A, B, C, D, E, and S. This gene encodes the alpha-1A subunit, which is predominantly expressed in neuronal tissue. Mutations in this gene are associated with 2 neurologic disorders, familial hemiplegic migraine and episodic ataxia 2. This gene also exhibits polymorphic variation due to (CAG)n-repeats. Multiple transcript variants encoding different isoforms have been found for this gene. In one set of transcript variants, the (CAG)n-repeats occur in the 3' UTR, and are not associated with any disease. But in another set of variants, an insertion extends the coding region to include the (CAG)n-repeats which encode a polyglutamine tract. Expansion of the (CAG)n-repeats from the normal 4-16 to 21-28 in the coding region is associated with spinocerebellar ataxia 6. [provided by RefSeq, Mar 2010]

CACNA1A: Voltage-sensitive calcium channels (VSCC) mediate the entry of calcium ions into excitable cells and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, gene expression, cell motility, cell division and cell death. The isoform alpha-1A gives rise to P and/or Q-type calcium currents. P/Q-type calcium channels belong to the 'high-voltage activated' (HVA) group and are blocked by the funnel toxin (Ftx) and by the omega-agatoxin- IVA (omega-Aga-IVA). They are however insensitive to dihydropyridines (DHP), and omega-conotoxin-GVIA (omega-CTx-GVIA). Defects in CACNA1A are the cause of spinocerebellar ataxia type 6 (SCA6). Spinocerebellar ataxia is a clinically and genetically heterogeneous group of cerebellar disorders. Patients show progressive incoordination of gait and often poor coordination of hands, speech and eye movements, due to degeneration of the cerebellum with variable involvement of the brainstem and spinal cord. SCA6 is mainly caused by expansion of a CAG repeat in the coding region of CACNA1A. There seems to be a correlation between the repeat number and earlier onset of the disorder. Defects in CACNA1A are the cause of familial hemiplegic migraine type 1 (FHM1); also known as migraine familial hemiplegic 1 (MHP1). FHM1, a rare autosomal dominant subtype of migraine with aura, is associated with ictal hemiparesis and, in some families, progressive cerebellar atrophy. Defects in CACNA1A are the cause of episodic ataxia type 2 (EA2); also known as acetazolamide-responsive hereditary paroxysmal cerebellar ataxia (APCA). EA2 is an autosomal dominant disorder characterized by acetozolamide- responsive attacks of ataxia, migraine-like symptoms, interictal nystagmus, and cerebellar atrophy. Belongs to the calcium channel alpha-1 subunit (TC 1.A.1.11) family. CACNA1A subfamily. 7 isoforms of the human protein are produced by alternative splicing.

Protein type: Membrane protein, multi-pass; Channel, calcium; Membrane protein, integral

Chromosomal Location of Human Ortholog: 19p13

Cellular Component: cell projection; cell soma; dendrite; cytoplasm; plasma membrane; integral to membrane; voltage-gated calcium channel complex; nucleus

Molecular Function: voltage-gated calcium channel activity; protein binding; syntaxin binding; metal ion binding; high voltage-gated calcium channel activity

Biological Process: cell death; vestibular nucleus development; musculoskeletal movement, spinal reflex action; gamma-aminobutyric acid secretion; regulation of axonogenesis; adult walking behavior; receptor clustering; cellular chloride ion homeostasis; synaptic transmission; behavioral response to pain; elevation of cytosolic calcium ion concentration; synaptogenesis; neurotransmitter metabolic process; negative regulation of neuron apoptosis; neuromuscular process controlling balance; cell growth; cerebellum maturation; synaptic transmission, glutamatergic; rhythmic synaptic transmission; regulation of acetylcholine secretion; dendrite morphogenesis; calcium ion-dependent exocytosis of neurotransmitter; glucose metabolic process; transmission of nerve impulse; spinal cord motor neuron differentiation; regulation of calcium ion-dependent exocytosis; cerebellar molecular layer development; calcium ion-dependent exocytosis; membrane depolarization; sulfur amino acid metabolic process; cerebellar Purkinje cell differentiation; energy reserve metabolic process; neuromuscular synaptic transmission; hormone metabolic process; regulation of insulin secretion; negative regulation of hormone biosynthetic process; gamma-aminobutyric acid signaling pathway

Disease: Spinocerebellar Ataxia 6; Migraine, Familial Hemiplegic, 1; Episodic Ataxia, Type 2