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Updated: Jul 16, 2026
08:47
Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
Deficiency in caspase-9 or caspase-3 induces compensatory caspase activation
1Section of Immunobiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Nature Medicine
|November 4, 2000
Summary
Targeting caspases for disease therapy is complex. Eliminating specific caspases doesn
Area of Science:
- Cellular biology
- Molecular mechanisms of apoptosis
Background:
- Dysregulation of apoptosis (programmed cell death) is implicated in numerous human diseases.
- Caspases, as key executioners of apoptosis, represent significant therapeutic targets.
Purpose of the Study:
- To investigate compensatory caspase activation in vivo using a Fas-mediated apoptosis model.
- To assess the therapeutic implications of caspase compensatory pathways.
Main Methods:
- Utilized an in vivo model of Fas-mediated apoptosis induced by the agonistic antibody Jo2.
- Examined hepatocyte apoptosis and mouse survival in caspase-deficient models.
- Investigated compensatory caspase activation in cultured hepatocytes exposed to UV and gamma irradiation.
Main Results:
- Elimination of specific caspases (caspase-9 or caspase-3) did not prevent apoptosis or death in vivo.
- Jo2-induced toxicity in caspase-deficient mice led to rapid activation of alternate caspases.
- Mitochondrial pathways, including Bid-mediated activation, were involved in compensatory caspase activation.
- UV and gamma irradiation also induced compensatory caspase activation in caspase-3 deficient hepatocytes.
Conclusions:
- Direct experimental evidence supports the existence of compensatory caspase activation pathways.
- Compensatory caspase activation is mediated through mitochondria.
- These findings necessitate consideration of compensatory mechanisms when developing caspase inhibitors for therapeutic use.
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