CaV1.2 | voltage-dependent, L type, alpha 1C 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
CaV1.2 Background Information
Overview:
CaV1.2 is a subunit of L-type voltage-dependent calcium channel. In the heart it forms a complex with the subunits β2 and α2δ1 in a 1:1:1 ratio. The alpha-1 consists of 24 transmembrane segments and is the pore forming element through which ions pass into the cell, whereas the β2 and α2δ1 subunits modulate the channel function. CaV1.2 is widely expressed in the smooth muscle, pancreatic cells, fibroblasts, and neurons. However, it is particularly important and well known for its expression in the heart where it mediates L-type currents, which causes calcium-induced calcium release from the ER Stores via ryanodine receptors. It depolarizes at -30 mV and helps define the shape of the action potential in cardiac and smooth muscle. CaV1.2 is inhibited by the action of STIM1.
Data Sheet:
Gene:
CACNA1C
Human Protein:
UniProt Q13936
Tissue:
Heart, brain, lymphocytes, prostate, bladder, uterus ,stomach, colon, placenta, adrenal gland
Function/ Application:
Ca2+ entry in excitable cells
Pathology:
Arterial hypertension, Long QT syndrome, schizophrenia, Timothy syndrome, BRGDA3, bipolar disorder, schizophrenia
Interaction:
Kir/Gem, CSN5/Jab1, β1-4 subunits, α2δ subunits, NF-κB, osteoprotegerin
Modulator:
Verapamil, nifedipine, kurtoxin, calcicludine, mibefradil, calciseptine, BAYK-8644, verapamil
Assays:
Patch Clamp: whole cell, room temperature
Particularities:
CaV channels often show a rundown phenomenon. Adequate intra- and extracellular solutions are essential for a good data quality.