The proteasome: overview of structure and functions

Proc Jpn Acad Ser B Phys Biol Sci. 2009;85(1):12-36. doi: 10.2183/pjab.85.12.


The proteasome is a highly sophisticated protease complex designed to carry out selective, efficient and processive hydrolysis of client proteins. It is known to collaborate with ubiquitin, which polymerizes to form a marker for regulated proteolysis in eukaryotic cells. The highly organized proteasome plays a prominent role in the control of a diverse array of basic cellular activities by rapidly and unidirectionally catalyzing biological reactions. Studies of the proteasome during the past quarter of a century have provided profound insights into its structure and functions, which has appreciably contributed to our understanding of cellular life. Many questions, however, remain to be elucidated.

Publication types

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

MeSH terms

  • Endopeptidases / chemistry
  • Endopeptidases / metabolism
  • Molecular Chaperones / chemistry*
  • Molecular Chaperones / metabolism
  • Proteasome Endopeptidase Complex / chemistry*
  • Proteasome Endopeptidase Complex / metabolism
  • Ubiquitin / chemistry*
  • Ubiquitin / metabolism
  • Ubiquitin-Protein Ligases / chemistry
  • Ubiquitin-Protein Ligases / metabolism


  • Molecular Chaperones
  • Ubiquitin
  • Ubiquitin-Protein Ligases
  • Endopeptidases
  • Proteasome Endopeptidase Complex