Caspases exist as inactive proenzymes that undergo proteolytic processing at conserved aspartic residues to produce two subunits, large and small, that dimerize to form the active enzyme.

[11] A key feature of caspases in the cell is that they are present as zymogens, termed procaspases, which are inactive until a biochemical change causes their activation.

[12] Under normal circumstances, caspases recognize tetra-peptide sequences on their substrates and hydrolyze peptide bonds after aspartic acid residues.

[19] In vitro, caspase-3 has been found to prefer the peptide sequence DEVDG (Asp-Glu-Val-Asp-Gly) with cleavage occurring on the carboxy side of the second aspartic acid residue (between D and G).

[25][26] This extrinsic activation then triggers the hallmark caspase cascade characteristic of the apoptotic pathway, in which caspase-3 plays a dominant role.

[27] Mangosteen (Garcinia mangostana) extract has been shown to inhibit the activation of caspase 3 in B-amyloid treated human neuronal cells.

[28] One means of caspase inhibition is through the IAP (inhibitor of apoptosis) protein family, which includes c-IAP1, c-IAP2, XIAP, and ML-IAP.

[29] Caspase 3 has been shown to interact with: Caspase-3 has been found to be necessary for normal brain development as well as its typical role in apoptosis, where it is responsible for chromatin condensation and DNA fragmentation.