scholarly journals p53 mRNA Metabolism Links with the DNA Damage Response

Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1446
Author(s):  
Sivakumar Vadivel Vadivel Gnanasundram ◽  
Ondrej Bonczek ◽  
Lixiao Wang ◽  
Sa Chen ◽  
Robin Fahraeus

Human cells are subjected to continuous challenges by different genotoxic stress attacks. DNA damage leads to erroneous mutations, which can alter the function of oncogenes or tumor suppressors, resulting in cancer development. To circumvent this, cells activate the DNA damage response (DDR), which mainly involves cell cycle regulation and DNA repair processes. The tumor suppressor p53 plays a pivotal role in the DDR by halting the cell cycle and facilitating the DNA repair processes. Various pathways and factors participating in the detection and repair of DNA have been described, including scores of RNA-binding proteins (RBPs) and RNAs. It has become increasingly clear that p53’s role is multitasking, and p53 mRNA regulation plays a prominent part in the DDR. This review is aimed at covering the p53 RNA metabolism linked to the DDR and highlights the recent findings.

Author(s):  
Paula Andrea Marin ◽  
Ricardo Obonaga ◽  
Raphael Souza Pavani ◽  
Marcelo Santos da Silva ◽  
Christiane Bezerra de Araujo ◽  
...  

DNA double-strand breaks (DSBs) are among the most deleterious lesions that threaten genome integrity. To address DSBs, eukaryotic cells of model organisms have evolved a complex network of cellular pathways that are able to detect DNA damage, activate a checkpoint response to delay cell cycle progression, recruit the proper repair machinery, and resume the cell cycle once the DNA damage is repaired. Cell cycle checkpoints are primarily regulated by the apical kinases ATR and ATM, which are conserved throughout the eukaryotic kingdom. Trypanosoma brucei is a divergent pathogenic protozoan parasite that causes human African trypanosomiasis (HAT), a neglected disease that can be fatal when left untreated. The proper signaling and accuracy of DNA repair is fundamental to T. brucei not only to ensure parasite survival after genotoxic stress but also because DSBs are involved in the process of generating antigenic variations used by this parasite to evade the host immune system. DSBs trigger a strong DNA damage response and efficient repair process in T. brucei, but it is unclear how these processes are coordinated. Here, by knocking down ATR in T. brucei using two different approaches (conditional RNAi and an ATR inhibitor), we show that ATR is required to mediate intra-S and partial G1/S checkpoint responses. ATR is also involved in replication fork stalling, is critical for H2A histone phosphorylation in a small group of cells and is necessary for the recruitment and upregulation of the HR-mediated DNA repair protein RAD51 after ionizing radiation (IR) induces DSBs. In summary, this work shows that apical ATR kinase plays a central role in signal transduction and is critical for orchestrating the DNA damage response in T. brucei.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3369-3369
Author(s):  
Magali Humbert ◽  
Michaela Medova ◽  
Barbara Geering ◽  
Wieslawa Blank-Liss ◽  
Hans-Uwe Simon ◽  
...  

Abstract Abstract 3369 Intact DNA damage response pathways are important for genomic fidelity of cells in order to avoid tumor formation. On the other hand, inhibition of DNA repair provides an important mechanism to enhance the therapeutic efficacy of DNA damaging agents such as gamma-irradiation. Thus, it is important to identify novel players in DNA damage response that might represent novel targets for combination therapies. Death-associated protein kinases (DAPK) are serine/threonine kinases believed to be involved in cell death and autophagy mechanisms, whereby particularly the role of DAPK1 has previously been investigated. The DAPK family is composed of five members: DAPK1, DAPK2 (or DRP-1), DAPK3 (or ZIP kinase), DRAK1 and DRAK2. DAPK1 and DAPK2 share 80% homology in the catalytic domain. Generally, the role of DAPK in DNA damage responses is not well studied. To analyze the role of DAPK1 and DAPK2 in response to gamma-irradiation, we used p53 wild-type REH B-cell acute lymphoblastic leukemia (B-ALL) cells as a model. In response to irradiation, DAPK1 protein expression increased paralleled by an increased of total p53, phospho-Ser20-p53 and p21WAF1/CIP1. DAPK2 expression, however, did not increase. Since upregulation of p21WAF1/CIP1, a classical p53 target in response to DNA damage leads to cell cycle arrest, we asked whether knocking down DAPK1 or DAPK2 might affect the cell cycle. Interestingly, knocking down DAPK2 but not DAPK1 led to a significant increase of S-phase cells upon irradiation. Moreover, knocking down DAPK2 attenuated the induction of DAPK1 upon irradiation indicating a DAPK2-DAPK1 cascade in DNA damage responses. Next, given the significant role of p21WAF1/CIP1 and p53 in DNA damage responses, we tested if DAPK2 might directly participate in a novel signaling pathway by interacting with these proteins. Indeed, pull down assays revealed that p21WAF1/CIP1 and p53 are novel DAPK2 interacting proteins. Clearly, further experiments are needed to define the DAPK2-DAPK1-p53- p21WAF1/CIP1 network in DNA repair pathways. In conclusion, we identified a novel role for DAPK1 and DAPK2 in DNA damage responses of B-ALL cells and propose a novel DAPK2/DAPK1/p53/ p21WAF1/CIP1 DNA damage regulatory pathway. Disclosures: No relevant conflicts of interest to declare.


2012 ◽  
Vol 104 ◽  
pp. 21
Author(s):  
M.A.T.M. Van Vugt ◽  
M. Krajewska ◽  
H. Sillje ◽  
A.M. Heijink ◽  
Y. Bisselink ◽  
...  

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4435-4435
Author(s):  
Herviou Laurie ◽  
Fanny Izard ◽  
Elke De Bruyne ◽  
Eva Desmedt ◽  
Anqi Ma ◽  
...  

Abstract Epigenetic regulation mechanisms - such as histone marks, DNA methylation and miRNA - are often misregulated in cancers and are associated with tumorigenesis and drug resistance. Multiple Myeloma (MM) is a malignant plasma cell disease that accumulates within the bone marrow. Epigenetic modifications in MM are associated not only with cancer development and progression, but also with resistance to chemotherapy. This epigenetic plasticity can be targeted with epidrugs, nowadays used in treatment of several cancers. We recently identified a significant overexpression of the lysine histone methyltransferase SETD8 in MM cells (HMCLs; N=40) compared with normal plasma cells (N=5) (P<0.001). SETD8 (also known as SET8, PR-Set7, KMT5A) is the sole enzyme responsible for the monomethylation of histone H4 at lysine 20 (H4K20me1) which has been linked to chromatin compaction and cell-cycle regulation. In addition, SETD8 induces the methylation of non-histone proteins, such as the replication factor PCNA, the tumor suppressor P53 and its stabilizing protein Numb. While SETD8-mediated methylation of P53 and Numb inhibits apoptosis, PCNA methylation upon SETD8 enhances the interaction with the Flap endonuclease FEN1 and promotes cancer cell proliferation. SETD8 is also implicated in DNA damage response, helping 53BP1 recruitment at DNA double-strand breaks. Consistent with this, overexpression of SETD8 is found in various types of cancer and has been directly implicated in breast cancer invasiveness and metastasis. A role of SETD8 in development of MM has however never been described. We found that high SETD8 expression is associated with a poor prognosis in 2 independent cohorts of newly diagnosed patients (UAMS-TT2 cohort - N=345 and UAMS-TT3 cohort - N=158). Specific SETD8 inhibition with UNC-0379 inhibitor, causing its degradation and H4K20me1 depletion, leads to significant growth inhibition of HMCLs (N=10) and the murine cell lines 5T33MM and 5TGM1. MM cells treated with UNC-0379 presented a G0/G1 cell cycle arrest after 24h of treatment, followed by apoptosis 48h later. To confirm that SETD8 inhibition is as efficient on primary MM cells from patients, primary MM cells (N=8) were co-cultured with their bone marrow microenvironment and recombinant IL-6 and treated for 4 days with UNC-0379. Interestingly, treatment of MM patient samples with UNC-0379 reduces the percentage of myeloma cells (65%; P<0.005) without significantly affecting the non-myeloma cells, suggesting a specific addiction of primary myeloma cells to SETD8 activity. Melphalan is an alkylating agent commonly used in MM treatment. As SETD8 is known to be involved in the DNA damage response, we investigated the effect of its combination with Melphalan on HMCLs. Results show that this particular drug combination strongly enhances double strand breaks in HMCLs monitored using 53BP1 foci formation and gH2AX detection. This result emphasizes a potential role of SETD8 in DNA repair in MM cells. Furthermore, GSEA analysis of patients with high SETD8 expression highlighted a significant enrichment of genes involved in DNA repair, MYC-MAX targets and MAPK pathway. Our study is the first to demonstrate the importance of SETD8 for MM cells survival and suggest that SETD8 inhibition represent a promising strategy to improve conventional treatment of MM with DNA damaging agents. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 21 (21) ◽  
pp. 8039
Author(s):  
Iwona Rzeszutek ◽  
Gabriela Betlej

DNA damage is a common phenomenon promoted through a variety of exogenous and endogenous factors. The DNA damage response (DDR) pathway involves a wide range of proteins, and as was indicated, small noncoding RNAs (sncRNAs). These are double-strand break-induced RNAs (diRNAs) and DNA damage response small RNA (DDRNA). Moreover, RNA binding proteins (RBPs) and RNA modifications have also been identified to modulate diRNA and DDRNA function in the DDR process. Several theories have been formulated regarding the synthesis and function of these sncRNAs during DNA repair; nevertheless, these pathways’ molecular details remain unclear. Here, we review the current knowledge regarding the mechanisms of diRNA and DDRNA biosynthesis and discuss the role of sncRNAs in maintaining genome stability.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1265-1265
Author(s):  
Christine von Klitzing ◽  
Florian Bassermann ◽  
Stephan W. Morris ◽  
Christian Peschel ◽  
Justus Duyster

Abstract The nuclear interaction partner of ALK (NIPA) is a nuclear protein identified by our group in a screen for NPM-ALK interaction partners. We recently reported that NIPA is an F-box protein that assembles with SKP1, Cul1 and Roc1 to establish a novel SCF-type E3 ubiquitin ligase. The formation of the SCFNIPA complex is regulated by cell cycle-dependent phosphorylation of NIPA that restricts SCFNIPA assembly from G1- to late S-phase, thus allowing its substrates to be active from late S-phase throughout mitosis. Proteins involved in cell cycle regulation frequently play a role in DNA damage checkpoints. We therefore sought to determine whether NIPA has a function in the cellular response to genotoxic stress. For this reason we treated NIH/3T3 cells with various DNA-damaging agents. Surprisingly, we observed phosphorylation of NIPA in response to some of these agents, including UV radiation. This phosphorylation was cell cycle phase independent and thus independent of the physiological cell cycle dependent phosphorylation of NIPA. The relevant phosphorylation site is identical to the respective site in the course of cell cycle-dependent phosphorylation of NIPA. Thus, phosphorylation of NIPA upon genotoxic stress would inactivate the SCFNIPA complex in a cell cycle independent manner. Interestingly, this phosphorylation site lies within a consensus site of the Chk1/Chk2 checkpoint kinases. These kinases are central to DNA damage checkpoint signaling. Chk1 is activated by ATR in response to blocked replication forks as they occur after treatment with UV. We performed experiments using the ATM/ATR inhibitor caffeine and the Chk1 inhibitor SB218078 to investigate a potential role of Chk1 in NIPA phosphorylation. Indeed, we found both inhibitors to prevent UV-induced phosphorylation of NIPA. Current experiments applying Chk1 knock-out cells will unravel the role of Chk1 in NIPA phosphorylation. Additional experiments were performed to investigate a function for NIPA in DNA-damage induced apoptosis. In this regard, we observed overexpression of NIPA WT to induce apoptosis in response to UV, whereas no proapoptotic effect was seen with the phosphorylation deficient NIPA mutant. Therefore, the phosphorylated form of NIPA may be involved in apoptotic signaling pathways. In summary, we present data suggesting a cell cycle independent function for NIPA. This activity is involved in DNA damage response and may be involved in regulating apoptosis upon genotoxic stress.


2010 ◽  
Vol 53 (1) ◽  
pp. 13-17 ◽  
Author(s):  
Aleš Tichý ◽  
Jiřina Vávrová ◽  
Jaroslav Pejchal ◽  
Martina Řezáčová

Ataxia-telangiectasia mutated kinase (ATM) is a DNA damage-inducible protein kinase, which phosphorylates plethora of substrates participating in DNA damage response. ATM significance for the cell faith is undeniable, since it regulates DNA repair, cell-cycle progress, and apoptosis. Here we describe its main signalling targets and discuss its importance in DNA repair as well as novel findings linked to this key regulatory enzyme in the terms of ionizing radiationinduced DNA damage.


Sign in / Sign up

Export Citation Format

Share Document