CACN gene family

Genes in the CACN family provide instructions for making calcium channels. These channels transport positively charged calcium atoms (calcium ions) into cells. Calcium channels play key roles in a cell's ability to generate and transmit electrical signals. Calcium ions are involved in many different cellular functions, including cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes.

Calcium channels are made up of several protein components (subunits), each of which is produced from a particular gene. The α1 (alpha-1) subunit is the largest and most important component of a calcium channel. It forms the hole (pore) through which calcium ions can flow. Several other subunits interact with the α1 subunit to help regulate the channel's function.

Calcium channels have critical functions in many different tissues. For example, these channels are abundant in muscles used for movement (skeletal muscles). For the body to move normally, skeletal muscles must contract and relax in a coordinated way. Muscle contractions are triggered by the flow of certain ions, including calcium, into muscle cells. By controlling the flow of calcium ions, calcium channels are part of the cellular machinery that initiates muscle contractions.

Additionally, calcium channels are present in heart (cardiac) muscle and in smooth muscle, which is found in the walls of organs such as the stomach, intestines, and lungs. Calcium channels also help transmit electrical signals within and between nerve cells (neurons) in the brain and throughout the body. Other cells that contain calcium channels include hormone-producing (endocrine) cells, pacemaker cells in the heart, and sensory cells (such as cells in the eye that detect light and color).