used that called L-type calcium channels CaV1 with its subunits being called CaV1.1, Cav1.2, CaV1.3, and CaV1.4. Research on the CaV1 subunits continues to reveal more about their structure, function, and pharmaceutical applications. Structure L-type Calcium Channels contain 5 different subunits, the α1(170–240 kDa), α2(150kDa), δ(17-25 kDa), β(50-78 kDa), and γ(32 kDa) subunits. The α2, δ, and β subunits are non-covalently bonded to the α1 subunit and modulate ion trafficking and biophysical properties of the α1 subunit. The α2 and δ subunits are in the extracellular space while the β and γ subunits are located in the cytosolic space. The α1 subunit is a heterotetramer that has four transmembrane regions, known as Domains I-IV, that cross the plasma six times as α-helices, being called S0-S6 (S0 and S1 together cross the membrane once). The α1 subunit as a whole contains the voltage sensing domain, the conduction pore, and gating apparatus. Like most voltage-gated ion channels, the α-subunit is composed of 4 subunits. Each subunit is formed by 6 alpha-helical, transmembrane domains that cross the membrane (numbered S1-S6). The S1-S4 subunits make up the voltage sensor, while S5-S6 subunits make up the selectivity filter. To sense the cell's voltage, the S1-S3 helices contain many negatively charged amino acids while S4 helices contain mostly positively charged amino acids with a P-loop connecting the S4 to S5 helices. After the S1-6 domains, there are six C domains that consist of two EF-hand motifs (C1-2 and C3-4) and a Pre-IQ domain (C5) and IQ domain (C6). There are also two EF-hand motifs on the N-terminus. Both the N and C terminus are in the cytosolic space with the C-terminus being much longer than the N-terminus. The β subunit is known to have four isoforms (β1-β4) to regulate the channel's functions and is connected to α1 through the α1 I and II linker in the cytosol at the β α1-binding pocket (ABP). Each isoform contains a src homology 3 domain (SH3) and a guanylate-kinase like domain (GK) that are separated by a HOOK domain, and three unstructured regions. The α2 and δ subunits are connected together by disulfide bonds (sometimes known as the α2δ subunit) and interact with α1. they have four known isoforms called α2δ-1 to α2δ-2 and contain a von Willebrand A (VWA) domain and a Cache domain. The α2 region is in the extracellular space while the δ region is in the