Caspase substrate,Z-Ile-Glu-Thr-Asp-AFC; Z-IETD-AFC

Z-IETD-AFC is a fluorogenic substrate for caspase-8 and granzyme B. Upon enzymatic cleavage by caspase-8 or granzyme B, 7-amino-4-trifluoromethylcoumarin (AFC) is released and its fluorescence can be used to quantify caspase-8 or granzyme B activity. AFC displays excitation/emission maxima of 400/505 nm, respectively.

Z-IETD-AFC is a fluorogenic caspase-8/granzyme B substrate. This substrate is hydrlyzed by caspase 8 to generate highly fluorescent 7-amido-4-trifluoromethylcoumarin (AFC).

Caspase substrates are a class of pharmacological agents that regulate apoptosis. Caspases are proteases that cleave specific proteins in the cell, leading to apoptosis. Pro-apoptotic proteins activate caspases, while anti-apoptotic proteins inhibit them. Caspase substrates can be either pro-caspase or anti-caspase, depending on the desired effect. They may also be used to regulate caspases without affecting their activity. The caspase substrate is cleaved by caspases and releases a polypeptide fragment that triggers apoptosis in some cells, but not others. For example, the Hl-60 cell line is resistant to the pro-apoptotic effects of the substrate because it contains an anti-apoptotic protein called Bcl-2. In contrast, myocardial cells contain pro-apoptotic proteins and are sensitive to the pro-apoptotic effects of the substrate.