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Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex
07:17

Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex

Published on: August 2, 2021

Caspase-2 is activated at the CD95 death-inducing signaling complex in the course of CD95-induced apoptosis

Inna N Lavrik1, Alexander Golks, Simone Baumann

  • 1Division of Immunogenetics, Tumorimmunology Program, German Cancer Research Center, Heidelberg. i.lavrik@dkfz.de

Blood
|July 11, 2006
PubMed

Insights

Procaspase-2 (caspase-2) is activated at the CD95 death-inducing signaling complex (DISC). However, caspase-2 does not initiate apoptosis via CD95 signaling in cells lacking caspase-8.

Area of Science:

  • Cell biology
  • Molecular biology
  • Immunology

Background:

  • Caspase-2 involvement in apoptosis is known, but its activation mechanism is unclear.
  • The precise role of caspase-2 in various apoptotic pathways requires further elucidation.

Purpose of the Study:

  • To investigate the molecular mechanism of procaspase-2 activation.
  • To determine the role of caspase-2 in CD95 (Fas/APO-1) mediated apoptosis.

Main Methods:

  • Recruitment of procaspase-2 to the death-inducing signaling complex (DISC) was analyzed.
  • Procaspase-2 activation at the DISC upon CD95 stimulation was assessed.
  • Experiments were conducted in human T- and B-cell lines, including caspase-8 deficient lines.

Main Results:

  • Procaspase-2 is recruited to the CD95 DISC in human T- and B-cells.
  • Procaspase-2 activation occurs at the DISC following CD95 stimulation.
  • Caspase-2 does not initiate CD95-induced apoptosis in caspase-8 deficient cells.

Conclusions:

  • Caspase-2 activation is dependent on its recruitment to the CD95 DISC.
  • Caspase-2 activation at the DISC does not initiate apoptosis in the absence of caspase-8.
  • Caspase-2 does not play a primary role in initiating CD95-mediated apoptosis.

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