p53 isoforms differentially impact on the POLι dependent DNA damage tolerance pathway
| Autor: | Stephanie Biber, Jean-Christophe Bourdon, Melanie Rall-Scharpf, Lisa Wiesmüller, Yitian Guo |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Gene isoform
DNA Replication Cancer Research DNA damage Mitomycin Tumor suppressor protein p53 Immunology DNA-Directed DNA Polymerase Models Biological Article Cellular and Molecular Neuroscience Proliferating Cell Nuclear Antigen Humans Protein Isoforms ddc:610 Tumour-suppressor proteins Replication protein A Polymerase Protein p53 Recombination Genetic biology QH573-671 Chemistry DNA replication Ubiquitination Cell Biology Chromatin Proliferating cell nuclear antigen Cell biology Mechanisms of disease DNA Polymerase iota biology.protein Stem cell Protein Multimerization DNS-Schädigung K562 Cells Cytology DDC 610 / Medicine & health Protein Binding Subcellular Fractions |
| Zdroj: | Cell Death and Disease, Vol 12, Iss 10, Pp 1-14 (2021) Cell Death & Disease |
| DOI: | 10.18725/oparu-46584 |
| Popis: | The recently discovered p53-dependent DNA damage tolerance (DDT) pathway relies on its biochemical activities in DNA-binding, oligomerization, as well as complex formation with the translesion synthesis (TLS) polymerase iota (POLι). These p53-POLι complexes slow down nascent DNA synthesis for safe, homology-directed bypass of DNA replication barriers. In this study, we demonstrate that the alternative p53-isoforms p53β, p53γ, Δ40p53α, Δ133p53α, and Δ160p53α differentially affect this p53-POLι-dependent DDT pathway originally described for canonical p53α. We show that the C-terminal isoforms p53β and p53γ, comprising a truncated oligomerization domain (OD), bind PCNA. Conversely, N-terminally truncated isoforms have a reduced capacity to engage in this interaction. Regardless of the specific loss of biochemical activities required for this DDT pathway, all alternative isoforms were impaired in promoting POLι recruitment to PCNA in the chromatin and in decelerating DNA replication under conditions of enforced replication stress after Mitomycin C (MMC) treatment. Consistent with this, all alternative p53-isoforms no longer stimulated recombination, i.e., bypass of endogenous replication barriers. Different from the other isoforms, Δ133p53α and Δ160p53α caused a severe DNA replication problem, namely fork stalling even in untreated cells. Co-expression of each alternative p53-isoform together with p53α exacerbated the DDT pathway defects, unveiling impaired POLι recruitment and replication deceleration already under unperturbed conditions. Such an inhibitory effect on p53α was particularly pronounced in cells co-expressing Δ133p53α or Δ160p53α. Notably, this effect became evident after the expression of the isoforms in tumor cells, as well as after the knockdown of endogenous isoforms in human hematopoietic stem and progenitor cells. In summary, mimicking the situation found to be associated with many cancer types and stem cells, i.e., co-expression of alternative p53-isoforms with p53α, carved out interference with p53α functions in the p53-POLι-dependent DDT pathway. publishedVersion |
| Databáze: | OpenAIRE |
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