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Detecting Anastasis In Vivo by CaspaseTracker Biosensor
20:16

Detecting Anastasis In Vivo by CaspaseTracker Biosensor

Published on: February 1, 2018

A comprehensive panel of turn-on caspase biosensors for investigating caspase specificity and caspase activation

Sujan S Shekhawat1, Sean T Campbell, Indraneel Ghosh

  • 1Department of Chemistry and Biochemistry, University of Arizona, 1306 E University Boulevard, Tucson, AZ 85721, USA.

Chembiochem : a European Journal of Chemical Biology
|August 19, 2011
PubMed

Insights

Researchers developed novel caspase biosensors to study apoptosis and inflammation. These tools revealed unexpected caspase activation pathways, offering new therapeutic targets for cancer and inflammatory diseases.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Background:

  • Caspases are crucial enzymes involved in apoptosis, differentiation, and proliferation.
  • They are significant therapeutic targets for cancer and inflammatory diseases.
  • Existing tools for studying caspase activity have limitations.

Purpose of the Study:

  • To develop and validate a comprehensive panel of caspase biosensors.
  • To probe caspase substrate cleavage specificity.
  • To systematically interrogate caspase activation pathways.

Main Methods:

  • Construction of a split-luciferase enabled bioluminescent caspase biosensor panel.
  • Testing biosensor specificity in vitro translation systems (rabbit reticulocyte lysate and wheat germ extract).
  • Application of biosensors to study caspase activation and inhibition in mammalian cytosolic extracts.

Main Results:

  • Rabbit reticulocyte lysate showed high endogenous caspase activity, unsuitable for specificity studies.
  • Wheat germ extract demonstrated specificity profiles consistent with traditional peptide probes.
  • Biosensors successfully monitored procaspase 3/7 activation/inhibition in cytosolic extracts.
  • Discovery of procaspase 3/7 activation by caspase 4/5.

Conclusions:

  • The developed caspase biosensors are effective tools for studying caspase activity and specificity.
  • Wheat germ extract is a suitable system for in vitro caspase specificity profiling.
  • The biosensors provide new insights into caspase activation pathways, including a novel caspase 4/5 mediated activation of procaspase 3/7.

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