PCNA-dependent accumulation of CDKN1A into nuclear foci after ionizing irradiation
| Autor: | Daniela Fink, Gisela Taucher-Scholz, Frank Tobias, J. H. Rudolph, Christine Blattner, Burkhard Jakob, Claudia Wiese |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Cyclin-Dependent Kinase Inhibitor p21
DNA Repair DNA damage DNA repair Biology Biochemistry Proliferating Cell Nuclear Antigen Radiation Ionizing medicine Humans DNA Breaks Double-Stranded Phosphorylation Molecular Biology Cell Nucleus X-Rays DNA replication Cell Biology Base excision repair Hydrogen Peroxide Fibroblasts Oxidants Molecular biology Chromatin Proliferating cell nuclear antigen Cell nucleus Protein Transport medicine.anatomical_structure Gamma Rays biology.protein Nucleotide excision repair Protein Binding |
| Zdroj: | DNA repair. 11(5) |
| ISSN: | 1568-7856 |
| Popis: | The cyclin-dependent kinase inhibitor CDKN1A/p21 confers cell-cycle arrest in response to DNA damage and inhibits DNA replication through its direct interaction with the proliferating cell nuclear antigen (PCNA) and cyclin/cyclin-dependent kinase complexes. Previously, we reported that in response to densely ionizing radiation CDKN1A rapidly is recruited to the sites of particle traversal, and that CDKN1A foci formation in response to heavy ions is independent of its transactivation by TP53. Here, we show that exposure of normal human fibroblasts to X-rays or to H2O2 also induces nuclear accumulations of CDKN1A. We find that CDKN1A foci formation in response to radiation damage is dependent on its dephosphorylation and on its direct physical interaction with PCNA. Live cell imaging analyses of ectopically expressed EGFP-CDKN1A and dsRed-PCNA show rapid recruitment of both proteins into foci after radiation damage. Detailed dynamic measurements reveal a slightly delayed recruitment of CDKN1A compared to PCNA, which is best described by bi-exponential curve fitting, taking the preceding binding of PCNA to DNA into account. We propose a regulatory role for CDKN1A in mediating PCNA function after radiation damage, and provide evidence that this role is distinct from its involvement in nucleotide excision repair and unrelated to double-strand break repair. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect