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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
Published on: December 27, 2016
Apoptosis control by death and decoy receptors
1Department of Molecular Oncology, Genentech Inc, 1 DNA Way, South San Francisco, CA 94080, USA.
Current Opinion in Cell Biology
|April 21, 1999
Summary
Researchers identified new death receptors (DR) and decoy receptors (DcR) related to Fas and tumor necrosis factor receptor 1 (TNFR1). Mouse gene knockout studies helped map the signaling pathways connecting these receptors to apoptosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Immunology
Background:
- Fas and tumor necrosis factor receptor 1 (TNFR1) are key death receptors initiating apoptosis.
- Apoptosis, or programmed cell death, is crucial for development and tissue homeostasis.
- Understanding death receptor signaling is vital for disease research.
Purpose of the Study:
- To identify and characterize novel homologues of Fas and TNFR1.
- To elucidate the functional roles of these novel receptors as either death or decoy receptors.
- To map the signaling pathways involved in death receptor-mediated apoptosis.
Main Methods:
- Bioinformatic analysis to identify novel receptor homologues.
- Ligand binding assays to assess receptor-ligand interactions.
- Mouse gene knockout studies to investigate in vivo functions.
- Western blotting and other molecular techniques to analyze signaling pathways.
Main Results:
- Discovery of novel death receptors: DR 3, 4, 5, and 6.
- Identification of novel decoy receptors: DcR 1, 2, and 3, which inhibit apoptosis signaling.
- Delineation of signaling pathways linking death receptors to the apoptotic machinery via mouse models.
Conclusions:
- The Fas and TNFR1 receptor superfamily is larger than previously known, including both pro-apoptotic and decoy members.
- These novel receptors play significant roles in regulating apoptosis.
- Mouse gene knockout studies provide critical insights into the in vivo function and regulation of death receptor pathways.
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