CaV2.2 | voltage-dependent, N type, alpha 1B subunit calcium channel
Family:
Calcium channels
Subgroups:
L-Type (CaV1.1–CaV1.4), P/Q-Type (CaV2.1), N-Type (CaV2.2), R-Type (CaV2.3), T-Type (CaV3.1–CaV3.3)
Topology:
Six transmembrane alpha helices (S1–S6), total of four homologous domains make up the tetrameric alpha subunit structure
Assembling:
One large alpha subunit forms a functional channel, accessory subunits ( α1, α2δ, β1-4, and γ) are crucial for robust expression, they functionally modulate the alpha subunit
CaV2.2: Background Information
CaV2.2 give rise to the N-type calcium currents and is distributed thourghout the entire body. These channels are known for their importance in the nervous system. They play a small role in the migration of immature neurons before the establishment of their mature synapses, and they are critically involved in the release of neurotransmitters, which is also similar to another type of calcium channels, known as P-type calcium channels. N-type calcium channels are targets for the development of drugs to relieve chronic and neuropathic pain. They are also used for the treatment of hypertension, Autism Spectrum Disorder, Osteoarthritis, and other medical diagnoses. Additionally, N-type calcium channels have known functions in the kidney, and heart.
Genes:
CACNA1B
Human Protein:
UniProt Q00975
Tissue:
brain, heart, lung, kidney
Function/ Application:
Neurotransmitter release in neurons, neurite outgrowth
Pathology:
Chronic pain, osteoarthritis, congenital generalized lipodystrophy, mental retardation, hypertension, diabetic neuropathy, Myoclonus-Dystonia syndrome, cancer, autism spectrum disorder
Interaction:
β1, β3, β4, α2δ, and possibly γ, laminin, ATP, RIMS1, FMR1, Amyloid Beta Precursor Protein Binding Family A Member 1, CaV2.1, CaV1.3, CaV3.1, CaV2.3, calmodulin, Guanine nucleotide binding protein gamma 4 and gamma 12
Modulator:
ω-Conotoxins, cadmium, gabapentin, nicardipine, TROX-1, ziconitide, (+-) Bay K 8644, cadmium
Assays:
Patch Clamp: whole cell, room temperature
Particularities:
CaV channels often show a rundown phenomenon. Adequate intra- and extrcellular solutions are essential for a good data quality.
Recommended Reviews:
Catterall WA, Perez-Reyes E, Snutch TP, Striessnig J (2005). "International Union of Pharmacology. XLVIII. Nomenclature and structure-function relationships of voltage-gated calcium channels". Pharmacol Rev. 57 (4): 411–25.
Data and Applications
CaV2.2 - Current-to-Voltage Relationship
Port-a-Patch data and applications:
Cells were kindly provided by Millipore.
Representative current responses of an individual HEK-293 cell expressing CaV2.2 to a standard voltage protocol. Average current-voltage relationship (n = 10). The error bars reflect the standard error of the mean (S.E.M.).
CaV2.2 - Current Voltage Relationship
Patchliner data and applications:
Cells were kindly provided by Millipore
Representative current responses of an individual cell expressing CaV2.2 to a I/V voltage protocol. The average peak current at 30 mV of all recorded cells was -698 ± 115 pA (n = 6).
CaV2.2 - Cadmium Block
Patchliner data and applications:
Cells were kindly provided by Millipore.
The image shows current response of an individual cell in the presence of increasing cadmium concentrations. The IC50 was calculated from the Hill fit to be 3.6 ± 0.4 μM (n = 5).
Application Notes
CaV2.2 - "Characterization of CaV2.2 on Nanion's Port-a-Patch"
Port-a-Patch application note: 
(0.6 MB)
Cells were kindly provided by Millipore.
CaV2.2 - "Characterization of CaV2.2 (HEK293) on Nanion's Patchliner"
Patchliner application note: (0.5 MB)
