¹Department of Biochemistry, La Trobe University, Victoria 3086, Australia

Correspondence: BA Callus, Department of Biochemistry, La Trobe University, Victoria 3086, Australia. Tel: +61 3 9479 1669; Fax: + 61 3 9479 2467; E-mail: b.callus@latrobe.edu.au

Received 7 June 2006; Revised 27 July 2006; Accepted 27 July 2006; Published online 8 September 2006.

Abstract

Caspases, key mediators of apoptosis, are a structurally related family of cysteine proteases that cleave their substrates at aspartic acid residues either to cause cell death or to activate cytokines as part of an immune response. They can be controlled upstream by the regulation of signals that lead to zymogen activation, or downstream by inhibitors that prevent them from reaching their substrates. This review specifically looks at caspase inhibitors as distinct from caspase regulators: those produced by the cell itself; those whose genes are carried by viruses; and artificial caspase inhibitors used for research and potentially as therapeutics.