Atractyloside‐induced release of cathepsin B, a protease with caspase‐processing activity

FEBS Letters

Fiers, Walter²  Grooten, Johan²  Van de Craen, Marc²  Sterling, Alistar¹  Vancompernolle, Katia²  Pynaert, Gwenda²  Totty, Nick¹  Vandenabeele, Peter²  De Vos, Kurt²  Van Herreweghe, Franky² 

[1] Ludwig Institute for Cancer Research, London Middlesex Branch, 91 Riding House Street, London W1P 8BT, UK;Department of Molecular Biology, Flanders Interuniversity Institute for Biotechnology and University of Ghent, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium

关键词: Caspase;    Cathepsin B;    Atractyloside;    Mitochondrion;   

DOI  :  10.1016/S0014-5793(98)01275-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Recent data show that a strong relation exists in certain cells between mitochondria and caspase activation in apoptosis. We further investigated this relation and tested whether treatment with the permeability transition (PT)-inducing agent atractyloside of Percoll-purified mitochondria released a caspase-processing activity. Following detection of procaspase-11 processing, we further purified this caspase-processing protease and identified it as cathepsin B. The purified cathepsin B, however, was found to be derived from lysosomes which were present as minor contaminants in the mitochondrial preparation. Besides procaspase-11, caspase-1 is also readily processed by cathepsin B. Procaspase-2, -6, -7, -14 are weak substrates and procaspase-3 is a very poor substrate, while procaspase-12 is no substrate at all for cathepsin B. In addition, cathepsin B induces nuclear apoptosis in digitonin-permeabilized cells as well as in isolated nuclei. All newly described activities of cathepsin B, namely processing of caspase zymogens and induction of nuclear apoptosis, are inhibited by the synthetic peptide caspase inhibitors z-VAD.fmk, z-DEVD.fmk and to a lesser extent by Ac-YVAD.cmk.

【 授权许可】

Unknown