Specific aspartyl and calpain proteases are required for neurodegeneration in C. elegans

Nature. 2002 Oct 31;419(6910):939-44. doi: 10.1038/nature01108.


Necrotic cell death underlies the pathology of numerous human neurodegenerative conditions. In the nematode Caenorhabditis elegans, gain-of-function mutations in specific ion channel genes such as the degenerin genes deg-1 and mec-4, the acetylcholine receptor channel subunit gene deg-3 and the G(s) protein alpha-subunit gene gsa-1 evoke an analogous pattern of degenerative (necrotic-like) cell death in neurons that express the mutant proteins. An increase in concentrations of cytoplasmic calcium in dying cells, elicited either by extracellular calcium influx or by release of endoplasmic reticulum stores, is thought to comprise a major death-signalling event. But the biochemical mechanisms by which calcium triggers cellular demise remain largely unknown. Here we report that neuronal degeneration inflicted by various genetic lesions in C. elegans requires the activity of the calcium-regulated CLP-1 and TRA-3 calpain proteases and aspartyl proteases ASP-3 and ASP-4. Our findings show that two distinct classes of proteases are involved in necrotic cell death and suggest that perturbation of intracellular concentrations of calcium may initiate neuronal degeneration by deregulating proteolysis. Similar proteases may mediate necrotic cell death in humans.

Publication types

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

MeSH terms

  • Animals
  • Aspartic Acid Endopeptidases / antagonists & inhibitors
  • Aspartic Acid Endopeptidases / deficiency
  • Aspartic Acid Endopeptidases / genetics
  • Aspartic Acid Endopeptidases / metabolism*
  • Caenorhabditis elegans / enzymology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism
  • Calcium / metabolism
  • Calpain / antagonists & inhibitors
  • Calpain / deficiency
  • Calpain / genetics
  • Calpain / metabolism*
  • Cell Death
  • Cell Survival
  • Genes, Reporter / genetics
  • Membrane Proteins*
  • Mutation / genetics
  • Necrosis
  • Neurodegenerative Diseases / enzymology*
  • Neurodegenerative Diseases / genetics
  • Neurodegenerative Diseases / pathology
  • Neurons / cytology
  • Neurons / enzymology
  • RNA Interference
  • Sodium Channels / genetics
  • Sodium Channels / metabolism


  • Caenorhabditis elegans Proteins
  • Mec-4 protein, C elegans
  • Membrane Proteins
  • Sodium Channels
  • Calpain
  • Aspartic Acid Endopeptidases
  • Calcium