Apoptosis execution

Although the detailed mechanism of apoptosis process is not completely clear, it has been determined that Caspase, namely caspase, plays an essential role in the process of apoptosis. The process of cell apoptosis is actually a cascade amplification reaction process of irreversible and limited hydrolysis of Caspase substrate. So far, at least 14 Caspases have been found. Caspase molecules have high homology and similar structure, all of which are cysteine family proteases, Caspases can be basically divided into two categories according to their functions: one is involved in cell processing, such as Pro-IL-1 β And Pro-IL-1 δ， Formation of active IL-1 β And IL-1 δ； The second type is involved in cell apoptosis, including caspase2,3,6,7,8,9.10. Caspase family generally has the following characteristics:

1) There is a cysteine activating site in the C-terminal homologous region, and this activating site domain is QACR/QG.

2) It usually exists in the form of zymogen, with a relative molecular weight of 29000-49000 (29-49KD). After being activated, its internal conservative aspartic acid residues are hydrolyzed to form two large (P20) and small (P10) subunits, and then form an active tetramer consisting of two pairs. Each P20/P10 heterodimer can be derived from the same precursor molecule or two different precursor molecules.

3) The end has a small or large original domain.

Caspases involved in apoptosis induction fall into two categories: initiators and effectors, which play a role in the upstream and downstream of death signal transduction, respectively.