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Caspases 3 and 7: key mediators of mitochondrial events of apoptosis

Saquib A Lakhani1, Ali Masud, Keisuke Kuida

  • 1Section of Immunobiology, Yale University School of Medicine, New Haven, CT 06520, USA.

Science (New York, N.Y.)
|February 14, 2006
PubMed

Insights

Caspases 3 and 7 are crucial for programmed cell death (apoptosis). Mice lacking these effector caspases showed severe cardiac defects and resistance to apoptosis, highlighting their essential role in cell survival.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Genetics

Background:

  • Apoptosis is a tightly regulated process involving upstream signals activating downstream effector caspases.
  • Caspase 3 and caspase 7 are key executioner enzymes in the apoptotic pathway.

Purpose of the Study:

  • To investigate the in vivo and in vitro roles of effector caspases 3 and 7 in apoptosis.
  • To determine the necessity of caspases 3 and 7 for cardiac development and mitochondrial apoptotic events.

Main Methods:

  • Generation of mice deficient in both caspase 3 and caspase 7.
  • Analysis of cardiac development in knockout mice.
  • Assessment of apoptosis resistance and mitochondrial function in caspase-deficient fibroblasts.

Main Results:

  • Caspase 3 and 7 deficient mice exhibited embryonic lethality with severe cardiac defects.
  • Fibroblasts lacking both caspases were resistant to apoptosis induced by various stimuli.
  • Mitochondrial membrane potential was preserved, and nuclear translocation of apoptosis-inducing factor (AIF) was impaired in these cells.
  • Early apoptotic events, including Bax translocation and cytochrome c release, were delayed.

Conclusions:

  • Caspases 3 and 7 are essential mediators of both mitochondrial and death receptor-mediated apoptosis.
  • These effector caspases play a critical role in initiating key mitochondrial events during apoptosis.
  • The absence of caspases 3 and 7 leads to developmental defects, underscoring their physiological importance.

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