CaV3.1 | voltage-dependent, T type, alpha 1G subunit calcium channel
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)
Six transmembrane alpha helices (S1–S6), total of four homologous domains make up the tetrameric alpha subunit structure
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
CaV3.1 Background Information
CaV3.1 give rise to the T-type currents: Low-voltage-activated calcium channels are referred to as 'T' type because their currents are both transient, owing to fast inactivation, and tiny, owing to small conductance. T-type channels are thought to be involved in pacemaker activity, low-threshold calcium spikes, neuronal oscillations and resonance, and rebound burst firing. CaV3.1 channels are found in neurons and cardiac tissue. It serves pacemaking functions in both central neurons and cardiac nodal cells and supports calcium signaling in secretory cells and vascular smooth muscle. Its involvement in the modulation of firing patterns of neurons is important for information processing as well as in cell growth processes. The potentiation of CaV3.1 T-type Ca2+ channels in the inferior olive contributes to the onset of the tremor in a pharmacological model of essential tremor.
brain neurons, cardiac nodal cells, smooth muscle cells
Ca2+pacemaker function, support calcium signalling in secretory cells and smooth muscle cells
Spinocerebellar ataxia 42, colorectal cancer, central pain syndrome, childhood absence epilepsy, osteogenesis imperfecta type i
β1-4 subunits, α2δ subunits, insulin, CaCNG3, Ras protein-specific guanine nucleotide-releasing factor 2, CaV1.2, Calsequestrin 2, TRPC5
Mibefradil, verapamil, zonisame, flunarizide, Bay K 8644, Nitrendipine
Patch Clamp: whole cell, room temperature
CaV channels often show a rundown phenomenon. Adequate intra- and extracellular solutions are essential for a good data quality.
Reviews and Links
- Catterall et al. (2005) International Union of Pharmacology. XLVIII. Nomenclature and structure-function relationships of voltage-gated calcium channels. Pharmacol Rev. 57 (4): 411–25.