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Proapoptotic Bid mediates the Atr-directed DNA damage response to replicative stress
1Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
Cell Death and Differentiation
|November 30, 2010
Summary
Proapoptotic BH3 interacting domain death agonist (Bid) amplifies the cellular response to DNA damage. Bid functions with the sensor complex in the Atm and Rad3-related (Atr)-directed DNA damage response, enhancing DNA repair and cell survival.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The proapoptotic protein Bid is a BH3-only Bcl-2 family member involved in apoptosis and DNA damage response.
- Bid acts at the intersection of DNA damage response pathways and apoptosis, influencing cell cycle checkpoints.
Purpose of the Study:
- To investigate the role of Bid in the Atm and Rad3-related (Atr)-directed DNA damage response.
- To elucidate Bid's function within the DNA damage sensor complex.
Main Methods:
- Immunofluorescence to detect Bid localization in nuclear foci with Replication Protein A (RPA).
- Biochemical assays to assess the association of Bid with the Atr/Atr-interacting protein (Atrip)/RPA complex.
- Analysis of Bid-deficient cells to evaluate the impact on DNA damage response pathways.
Main Results:
- Bid localizes to nuclear foci with RPA and associates with the Atr/Atrip/RPA complex during replicative stress.
- Bid-deficient cells exhibit impaired responses to replicative stress, including reduced Atr/Atrip accumulation and DNA synthesis recovery.
- Bid deficiency leads to decreased activation of checkpoint kinase 1 and RPA phosphorylation.
Conclusions:
- Bid plays a direct role in amplifying the Atr-directed cellular response to replicative DNA damage.
- Bid functions at the sensor complex level to modulate DNA damage signaling.
- These findings highlight Bid's critical role in maintaining genomic stability following DNA damage.
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