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Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
CK2 phosphorylates TNFAIP1 to affect its subcellular localization and interaction with PCNA.
Liping Yang1, Ning Liu, Xiang Hu
1Key laboratory of Protein Chemistry and Developmental Biology, Ministry of Education of China, Department of Biochemistry and Molecular Biology, College of Life Science, Hunan Normal University, Changsha, China.
Molecular Biology Reports
|October 24, 2009
Summary
Tumor necrosis factor alpha-induced protein 1 (TNFAIP1) interacts with CK2beta, a protein kinase. Phosphorylation by CK2 enhances TNFAIP1
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Tumor necrosis factor alpha-induced protein 1 (TNFAIP1) is involved in DNA synthesis, repair, and apoptosis.
- The precise functions and regulatory mechanisms of TNFAIP1 remain largely uncharacterized.
- Understanding TNFAIP1's interactions and post-translational modifications is crucial for elucidating its role in cellular processes and human diseases.
Purpose of the Study:
- To identify proteins that interact with TNFAIP1.
- To investigate the role of protein kinase CK2 (CK2) in regulating TNFAIP1 activity.
- To determine how CK2-mediated phosphorylation affects TNFAIP1's cellular localization and function.
Main Methods:
- Yeast two-hybrid screening of a HeLa cDNA library using TNFAIP1 as bait to identify interacting partners.
- In vitro kinase assays to assess CK2's ability to phosphorylate TNFAIP1.
- In vivo studies to confirm phosphorylation and analyze its effects on TNFAIP1 localization and interactions.
Main Results:
- CK2beta was identified as a TNFAIP1-interacting protein.
- CK2 was shown to phosphorylate TNFAIP1 both in vitro and in vivo.
- Phosphorylation by CK2 promoted TNFAIP1 nuclear localization and enhanced its interaction with PCNA (proliferating cell nuclear antigen).
Conclusions:
- CK2beta is a novel interacting partner of TNFAIP1.
- CK2-mediated phosphorylation is a key regulatory mechanism for TNFAIP1.
- Phosphorylation facilitates TNFAIP1's nuclear import and interaction with PCNA, suggesting a role in DNA-related processes.
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