Caspases are a family of inactive proenzymes that play a crucial role in cell apoptosis, which is the scheduled death of cells. The role of caspase 3 in apoptosis is to cleave and activate caspases 6, 7 and 9 in order to break down the apoptotic cells before removal. After this process, the caspase 3 protein is cleaved and broken down itself by caspase 8 and 10, as well as any inactive caspase 9 proteins that have yet to be cleaved themselves. The sequential cleaving and activation of these proteins is crucial to the execution stage of preprogrammed cellular death.
The role of caspase 3 in apoptosis is to activate the stages of cellular death in a non-traumatic manner. In contrast to necrosis, which is the traumatic destruction of cells, apoptosis is the process by which cells are broken down and destroyed in a scheduled and controlled manner to allow for various growths and developments in an organism. The process of apoptosis is the reason fingers and toes split at the embryonic stage of organism development. The controlled cellular death allows the digits to separate without trauma. Caspase 3 is vital to this process because it allows the process to progress in sequence, with no surprise events that would otherwise cause undue damage to the remaining cells.
When the process is under way, the purpose of caspase 3 in apoptosis is to actually cleave the key cellular proteins. This is achieved by a cascade effect, beginning when a death receptor based on the cell surface transmits the apoptotic signals to the preceding caspase proteins, activating them. These caspase proteins activate the next proteins in the sequence, eventually leading to the effector caspase, such as caspase 3. These caspases are directly responsible for the cleavage of cellular proteins, such as cytoskeletal proteins, that lead to the morphological changes, including the splitting of digits, that is observed in cells undergoing apoptosis.
It is believed that the role of caspase 3 in apoptosis could, when better understood, lead to a better understanding of illnesses such as Alzheimer’s disease. As the caspase 3 protein cleaves the cells, it can sometimes cause damage to areas of the body. Research indicates that this could be a cause of mental disorders. It is believed that a greater understanding of the mechanisms of caspase 3 in apoptosis will reveal how this process happens and could lead to treatment.