Structure and physiological function of calpains

Biochem J. 1997 Dec 15;328 ( Pt 3)(Pt 3):721-32. doi: 10.1042/bj3280721.


For a long time now, two ubiquitously expressed mammalian calpain isoenzymes have been used to explore the structure and function of calpain. Although these two calpains, mu- and m-calpains, still attract intensive interest because of their unique characteristics, various distinct homologues to the protease domain of mu- and m-calpains have been identified in a variety of organisms. Some of these 'novel' calpain homologues are involved in important biological functions. For example, p94 (also called calpain 3), a mammalian calpain homologue predominantly expressed in skeletal muscle, is genetically proved to be responsible for limb-girdle muscular dystrophy type 2A. Tra-3, a calpain homologue in nematodes, is involved in the sex determination cascade during early development. PalB, a key gene product involved in the alkaline adaptation of Aspergillus nidulans, is the first example of a calpain homologue present in fungi. These findings indicate various important functional roles for intracellular proteases belonging to the calpain superfamily.

Publication types

  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Apoptosis
  • Brain / physiology
  • Calcium / metabolism
  • Calcium-Binding Proteins / chemistry
  • Calpain / antagonists & inhibitors
  • Calpain / chemistry*
  • Calpain / physiology*
  • Cysteine Endopeptidases / chemistry
  • Cysteine Endopeptidases / metabolism
  • Cysteine Proteinase Inhibitors / chemistry
  • Cysteine Proteinase Inhibitors / pharmacology
  • Humans
  • Molecular Sequence Data
  • Sex Determination Processes


  • Calcium-Binding Proteins
  • Cysteine Proteinase Inhibitors
  • Calpain
  • Cysteine Endopeptidases
  • Calcium