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Detection and Isolation of Apoptotic Bodies to High Purity
12:17

Detection and Isolation of Apoptotic Bodies to High Purity

Published on: August 12, 2018

Apoptosome assembly

Yigong Shi1

  • 1Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey, USA.

Methods in Enzymology
|July 30, 2008
PubMed

Insights

The apoptosome, a protein complex crucial for apoptosis, assembles differently across species. Mammalian, fruit fly, and worm apoptosomes utilize distinct proteins and mechanisms for caspase activation during programmed cell death.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The apoptosome is a key protein complex that initiates apoptosis by activating initiator caspases.
  • Understanding apoptosome assembly is critical for comprehending programmed cell death pathways.

Purpose of the Study:

  • To describe the assembly mechanisms of three related apoptosomes from mammals, fruit flies (Drosophila melanogaster), and worms (Caenorhabditis elegans).
  • To highlight the conserved and divergent aspects of apoptosome formation across different species.

Main Methods:

  • Comparative analysis of biochemical and structural data.
  • Review of existing literature on apoptosome assembly in model organisms.

Main Results:

  • Mammalian apoptosome assembly involves Apaf-1, cytochrome c, and ATP/dATP binding for caspase-9 activation.
  • Drosophila melanogaster apoptosome assembly utilizes the Apaf-1 homologue Dark/Hac-1/Dapaf-1 to activate Dronc.
  • Caenorhabditis elegans apoptosome assembly involves CED-4 oligomerization, regulated by EGL-1 and CED-9.

Conclusions:

  • Apoptosome assembly pathways exhibit species-specific variations while serving the conserved function of initiating apoptosis.
  • Biochemical and structural insights continue to elucidate the intricate mechanisms of apoptosome formation and function.

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