Caspase-mediated cleavage of syntaxin 5 and giantin accompanies inhibition of secretory traffic during apoptosis

J Cell Sci. 2004 Mar 1;117(Pt 7):1139-50. doi: 10.1242/jcs.00950. Epub 2004 Feb 17.

Abstract

We report the caspase-dependent cleavage of two Golgi-associated transport factors during apoptosis. The tethering factor giantin is rapidly cleaved both in vitro and in vivo at a conserved site, to generate a stable membrane-anchored domain and a soluble domain that is subject to further caspase-dependent cleavage. The t-SNARE syntaxin 5 is also cleaved rapidly, resulting in the separation of the catalytic membrane-proximal domain from an N-terminal regulatory domain. Cleavage of giantin and syntaxin 5 is accompanied by a cessation of vesicular transport between the ER and the Golgi complex, which first manifests itself as a block in ER exit. The contribution that such an inhibition of trafficking may make towards the generation of an apoptotic phenotype is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / physiology*
  • Biological Transport, Active
  • Caspase 3
  • Caspases / metabolism*
  • Endoplasmic Reticulum / metabolism
  • Golgi Apparatus / metabolism
  • Golgi Matrix Proteins
  • HeLa Cells
  • Humans
  • In Vitro Techniques
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mutagenesis, Site-Directed
  • Phenotype
  • Protein Structure, Tertiary
  • Qa-SNARE Proteins
  • Rats
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism

Substances

  • Golgi Matrix Proteins
  • Membrane Proteins
  • Qa-SNARE Proteins
  • Recombinant Proteins
  • macrogolgin
  • CASP3 protein, human
  • Casp3 protein, rat
  • Caspase 3
  • Caspases