Granzyme K (E6Z6O) Rabbit mAb #98946

Granzymes are a family of serine proteases expressed by cytotoxic T lymphocytes and natural killer (NK) cells and are key components of immune responses to pathogens and transformed cells (1). Granzymes are synthesized as zymogens and are processed into mature enzymes by cleavage of a leader sequence. They are released by exocytosis in lysosome-like granules containing perforin, a membrane pore-forming protein. Granzyme B has the strongest apoptotic activity of all the granzymes as a result of its caspase-like ability to cleave substrates at aspartic acid residues thereby activating procaspases directly and cleaving downstream caspase substrates (2,3).
Granzyme K has tryptase-like activity with a preference for cleaving its specific substrates after basic residues, arginine or lysine (4-7). Granzyme K is expressed by NK T cells, cytotoxic T cells, and NK cells (8,9). After perforin-mediated entry into a target cell, Granzyme K induces apoptosis via generation of reactive oxygen species, DNA damage, and BID-dependent mitochondrial damage (10-12).