About CALM / Calmodulin:
Calcium is said to be the most abundant mineral element found inside the human body, followed closely only by the element known as phosphorus. This may not come as a big surprise, as most people are aware of the fact that average human bones get their strength and stability from around two kilos of calcium and phosphorus. To add to this, the human body also utilizes small amounts of calcium ions to complete what are referred to as ‘active duties’. These activities are mostly related to cell signaling, controlling processes like the contraction of muscles, nerve signaling, fertilisation as well as cell division.
With the help of calcium pumps and several forms of calcium binding proteins, your cells can keep internal calcium levels around 1000-10,000 times lower than the calcium levels that are in your blood. As a result, when calcium is actually released into your cells it will communicate with calcium sensing proteins and use this exchange as a trigger for things like muscle contraction, the release of insulin from your pancreas, and even blocking entry to any additional sperm cells after an egg has been successfully fertilised.
Calmodulin is a calcium modulated protein. It is found frequently in the cytoplasm of any higher cell, and has been conserved and maintained throughout the process of human evolution. CALM acts as an intermediary protein that assesses and addresses calcium levels, relaying signals to lots of different enzymes which are sensitive to calcium, as well as ion channels and other specific proteins. Calmodulin is described as a small dumbbell shaped protein which is composed of two ‘globular’ domains, connected to each other by a flexible linker. Each end must bind to two calcium ions to complete their activities successfully.