Cellular and Molecular Life Sciences

, Volume 66, Issue 15, pp 2427–2443 | Cite as

Intracellular protein degradation in mammalian cells: recent developments

  • Erwin Knecht
  • Carmen Aguado
  • Jaime Cárcel
  • Inmaculada Esteban
  • Juan Miguel Esteve
  • Ghita Ghislat
  • José Félix Moruno
  • José Manuel Vidal
  • Rosana Sáez


In higher organisms, dietary proteins are broken down into amino acids within the digestive tract but outside the cells, which incorporate the resulting amino acids into their metabolism. However, under certain conditions, an organism loses more nitrogen than is assimilated in the diet. This additional loss was found in the past century to come from intracellular proteins and started an intensive research that produced an enormous expansion of the field and a dispersed literature. Therefore, our purpose is to provide an updated summary of the current knowledge on the proteolytic machinery involved in intracellular protein degradation and its physiological and pathological relevance, especially addressed to newcomers in the field who may find further details in more specialized reviews. However, even providing a general overview, this is an extremely wide field and, therefore, we mainly focus on mammalian cells, while other cells will be mentioned only for comparison purposes.


Intracellular protein degradation Proteases Proteasomes Ubiquitin Lysosomes Autophagy Cell injury 


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Copyright information

© Birkhäuser Verlag, Basel/Switzerland 2009

Authors and Affiliations

  • Erwin Knecht
    • 1
    • 2
  • Carmen Aguado
    • 2
  • Jaime Cárcel
    • 1
  • Inmaculada Esteban
    • 2
  • Juan Miguel Esteve
    • 1
  • Ghita Ghislat
    • 1
  • José Félix Moruno
    • 1
  • José Manuel Vidal
    • 1
  • Rosana Sáez
    • 3
  1. 1.Centro de Investigación Príncipe FelipeValenciaSpain
  2. 2.Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIIIValenciaSpain
  3. 3.Departamento de Biología CelularUniversidad de ValenciaBurjassotSpain

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