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Updated: May 9, 2026
14:32
Deacetylation Assays to Unravel the Interplay between Sirtuins (SIRT2) and Specific Protein-substrates
Published on: February 27, 2016
SIRT2 directs the replication stress response through CDK9 deacetylation
Hui Zhang1, Seong-Hoon Park, Brooke G Pantazides
1Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA.
Summary
Sirtuin 2 (SIRT2) regulates DNA replication stress responses by deacetylating cyclin-dependent kinase 9 (CDK9). This deacetylation stimulates CDK9 activity, promoting cell recovery and maintaining genome integrity, highlighting SIRT2's tumor suppressor role.
Area of Science:
- Cellular Biology
- Molecular Biology
- Genetics
Background:
- Sirtuin 2 (SIRT2) is a deacetylase involved in acetylome signaling and genome integrity.
- SIRT2 functions as a tumor suppressor in mice.
- Replication stress responses are critical for maintaining genomic stability.
Purpose of the Study:
- To investigate the role of SIRT2 in regulating DNA replication stress responses.
- To elucidate the mechanism by which SIRT2 controls recovery from replication arrest.
- To define SIRT2's function in maintaining genome integrity and its tumor suppressor activity.
Main Methods:
- Investigated SIRT2's role in replication stress responses using SIRT2-deficient models.
- Analyzed the interaction and deacetylation of cyclin-dependent kinase 9 (CDK9) by SIRT2.
- Assessed the impact of CDK9 acetylation status on replication stress recovery.
Main Results:
- SIRT2 deficiency leads to sensitivity to replication stress and impaired recovery from arrest.
- SIRT2 deacetylates CDK9 at lysine 48, enhancing its kinase activity and promoting recovery.
- Wild-type CDK9, but not acetylated CDK9, rescues the replication stress defects in SIRT2-deficient cells.
Conclusions:
- SIRT2 regulates replication stress responses by deacetylating CDK9, thereby stimulating its kinase activity.
- This SIRT2-CDK9 interaction is crucial for recovery from replication arrest and maintaining genome integrity.
- SIRT2's function in regulating these checkpoint pathways provides a mechanism for its tumor suppressor activity.
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