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Modified Annexin V/Propidium Iodide Apoptosis Assay For Accurate Assessment of Cell Death
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Connected to death: the (unexpurgated) mitochondrial pathway of apoptosis

Diana Spierings1, Gavin McStay, Maya Saleh

  • 1La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA.

Science (New York, N.Y.)
|October 8, 2005
PubMed

Insights

The mitochondrial pathway of apoptosis relies on mitochondrial outer membrane permeabilization (MOMP). Bcl-2 family proteins control this crucial step, regulating cell death.

Area of Science:

  • Cellular biology
  • Molecular biology
  • Biochemistry

Background:

  • Apoptosis, or programmed cell death, is essential for development and tissue homeostasis.
  • The mitochondrial pathway is a major route for initiating apoptosis in vertebrates.
  • Mitochondrial outer membrane permeabilization (MOMP) is a critical event releasing proteins that activate caspases.

Purpose of the Study:

  • To illustrate the molecular pathways governing the mitochondrial pathway of apoptosis.
  • To highlight the regulatory roles of Bcl-2 family proteins in controlling MOMP.
  • To map the signaling network upstream and downstream of MOMP.

Main Methods:

  • Utilized the Connections Map database from Science's Signal Transduction Knowledge Environment (STKE).
  • Analyzed and visualized signaling pathways involved in apoptosis.
  • Focused on the regulation of mitochondrial outer membrane permeabilization.

Main Results:

  • The mitochondrial pathway of apoptosis is primarily controlled by events "upstairs" of MOMP.
  • Bcl-2 family proteins are key regulators that mediate and control MOMP.
  • Caspase activation, the "downstairs" event, orchestrates cellular dismantling.

Conclusions:

  • The regulation of apoptosis is heavily concentrated at the level of MOMP control.
  • Understanding the upstream regulators, particularly Bcl-2 proteins, is crucial for comprehending apoptotic signaling.
  • The Connections Map provides a valuable resource for visualizing these complex cellular processes.

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