Regulated cell death: signaling and mechanisms
1Genentech Inc., South San Francisco, California 94080;
Annual Review of Cell and Developmental Biology
|August 24, 2014
Summary
Cell turnover involves passive and active cell death. Active cell death, including apoptosis and necroptosis, is regulated, with necroptosis being less understood and distinct from caspase-dependent apoptosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Immunology
Background:
- Cell turnover is essential for metazoan life, involving both passive and active cell death pathways.
- Passive cell death results from severe damage and can harm the organism.
- Active cell death is a regulated process crucial for organismal survival.
Purpose of the Study:
- To elucidate the mechanisms controlling regulated cell death.
- To compare and contrast apoptosis and necroptosis.
- To highlight current understanding of signaling pathways in regulated cell death.
Main Methods:
- Review of existing literature on cell death signaling.
- Analysis of signaling components regulating apoptosis and necroptosis.
- Comparison of caspase-dependent (apoptosis) and caspase-independent (necroptosis) pathways.
Main Results:
- Apoptosis and necroptosis are distinct forms of regulated cell death.
- Both pathways can be initiated by internal or external signals.
- Caspases execute apoptosis, while necroptosis is suppressed by caspase activity.
Conclusions:
- Regulated cell death pathways, particularly necroptosis, require further investigation.
- Understanding these pathways is key to comprehending metazoan survival and disease.
- Key signaling molecules regulate both apoptosis and necroptosis, but through distinct mechanisms.
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