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Activation of Apoptosis by Cytoplasmic Microinjection of Cytochrome c
Published on: June 29, 2011
Mitochondria localization and dimerization are required for CIDE-B to induce apoptosis
1Laboratory of Apoptosis Regulation, Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609, Singapore.
The Journal of Biological Chemistry
|June 6, 2000
Summary
Cell death-inducing DFF45-like effector (CIDE)-B induces apoptosis by localizing to mitochondria and forming dimers. Both mitochondrial localization and dimerization are essential for CIDE-B
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Cell death-inducing DFF45-like effector (CIDE)-B is a novel apoptosis-inducing factor.
- CIDE-B shares homology with the DNA fragmentation factor (DFF).
- The precise mechanism of CIDE-B-mediated apoptosis remains largely unelucidated.
Purpose of the Study:
- To elucidate the molecular mechanism of CIDE-B-induced apoptosis.
- To investigate the subcellular localization and oligomerization of CIDE-B.
- To determine the functional significance of CIDE-B localization and dimerization in apoptosis.
Main Methods:
- Subcellular localization studies using protein expression and imaging.
- Yeast two-hybrid assays and co-immunoprecipitation to assess dimerization.
- Serial deletion analysis to map functional domains of CIDE-B.
Main Results:
- CIDE-B protein localizes to mitochondria.
- CIDE-B forms homodimers and heterodimers with other CIDE family members.
- Mitochondrial localization and dimerization are mediated by overlapping C-terminal amino acid residues.
- Both mitochondrial localization and dimerization are critical for CIDE-B-induced apoptosis.
Conclusions:
- CIDE-B induces apoptosis through a mechanism involving mitochondrial localization.
- The formation of homo- or heterodimeric complexes of CIDE-B is essential for its apoptotic function.
- The C-terminal region of CIDE-B contains overlapping signals for mitochondrial targeting and dimerization, crucial for apoptosis induction.
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