Selective disruption of lysosomes in HeLa cells triggers apoptosis mediated by cleavage of Bid by multiple papain-like lysosomal cathepsins

J Biol Chem. 2004 Jan 30;279(5):3578-87. doi: 10.1074/jbc.M308347200. Epub 2003 Oct 27.


Increasing evidence suggests that lysosomal proteases are actively involved in apoptosis. Using HeLa cells as the model system, we show that selective lysosome disruption with L-leucyl-L-leucine methyl ester results in apoptosis, characterized by translocation of lysosomal proteases into the cytosol and by the cleavage of a proapoptotic Bcl-2-family member Bid. Apoptosis and Bid cleavage, but not translocation of lysosomal proteases to the cytosol, could be prevented by 15 microM L-trans-epoxysuccinyl(OEt)-Leu-3-methylbutylamide, an inhibitor of papain-like cysteine proteases. Incubation of cells with 15 microM N-benzoyloxycarbonyl-VAD-fluoromethyl ketone prevented apoptosis but not Bid cleavage, suggesting that cathepsin-mediated apoptosis in this system is caspase-dependent. In vitro experiments performed at neutral pH showed that papain-like cathepsins B, H, L, S, and K cleave Bid predominantly at Arg(65) or Arg(71). No Bid cleavage was observed with cathepsins C and X or the aspartic protease cathepsin D. Incubation of full-length Bid treated with cathepsins B, H, L, and S resulted in rapid cytochrome c release from isolated mitochondria. Thus, Bid may be an important mediator of apoptosis induced by lysosomal disruption.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Apoptosis*
  • BH3 Interacting Domain Death Agonist Protein
  • Carrier Proteins / metabolism
  • Carrier Proteins / physiology*
  • Caspase 8
  • Caspases / metabolism
  • Cathepsins / metabolism*
  • Cell Line
  • Cell Line, Tumor
  • Cytochromes c / metabolism
  • Cytosol / metabolism
  • Flow Cytometry
  • HeLa Cells
  • Humans
  • Hydrogen-Ion Concentration
  • Liver / metabolism
  • Lysosomes / metabolism*
  • Mice
  • Mitochondria / metabolism
  • Models, Biological
  • Models, Molecular
  • Myocardium / metabolism
  • Papain / chemistry*
  • Protein Structure, Secondary
  • Protein Transport
  • Recombinant Proteins / metabolism
  • Temperature
  • Transfection


  • BH3 Interacting Domain Death Agonist Protein
  • BID protein, human
  • Bid protein, mouse
  • Carrier Proteins
  • Recombinant Proteins
  • Cytochromes c
  • Cathepsins
  • CASP8 protein, human
  • Casp8 protein, mouse
  • Caspase 8
  • Caspases
  • Papain