scholarly journals DNA Damage-Dependent Nuclear Dynamics of the Mre11 Complex

2001 ◽  
Vol 21 (1) ◽  
pp. 281-288 ◽  
Author(s):  
Olga K. Mirzoeva ◽  
John H. J. Petrini
Keyword(s):  
Dna Damage ◽  
Cellular Response ◽  
Human Fibroblasts ◽  
Strand Break ◽  
Immunofluorescent Localization ◽  
Nuclear Retention ◽  
Atm Kinase ◽  
Mre11 Complex ◽  
Previous Demonstration

ABSTRACT The Mre11 complex has been implicated in diverse aspects of the cellular response to DNA damage. We used in situ fractionation of human fibroblasts to carry out cytologic analysis of Mre11 complex proteins in the double-strand break (DSB) response. In situ fractionation removes most nucleoplasmic protein, permitting immunofluorescent localization of proteins that become more avidly bound to nuclear structures after induction of DNA damage. We found that a fraction of the Mre11 complex was bound to promyelocyte leukemia protein bodies in undamaged cells. Within 10 min after gamma irradiation, nuclear retention of the Mre11 complex in small granular foci was observed and persisted until 2 h postirradiation. In light of the previous demonstration that the Mre11 complex associated with ionizing radiation (IR)-induced DSBs, we infer that the protein retained under these conditions was associated with DNA damage. We also observed increased retention of Rad51 following IR treatment, although IR induced Rad51 foci were distinct from Mre11 foci. The ATM kinase, which phosphorylates Nbs1 during activation of the S-phase checkpoint, was not required for the Mre11 complex to associate with DNA damage. These data suggest that the functions of the Mre11 complex in the DSB response are implicitly dependent upon its ability to detect DNA damage.

The Cellular Response to DNA Damage Induced by the Enediynes C-1027 and Neocarzinostatin Includes Hyperphosphorylation and Increased Nuclear Retention of Replication Protein A (RPA) and Trans Inhibition of DNA Replication†

Biochemistry ◽  
2001 ◽  
Vol 40 (15) ◽  
pp. 4792-4799 ◽  
Author(s):  
Mary M. McHugh ◽  
Xia Yin ◽  
Shu-Ru Kuo ◽  
Jen-Sing Liu ◽  
Thomas Melendy ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Replication ◽  
Cellular Response ◽  
Protein A ◽  
Replication Protein A ◽  
Replication Protein ◽  
Nuclear Retention

Control of genome stability by Slx protein complexes

2009 ◽  
Vol 37 (3) ◽  
pp. 495-510 ◽  
Author(s):  
John Rouse
Keyword(s):  
Dna Damage ◽  
Dna Replication ◽  
Protein Interactions ◽  
Cellular Response ◽  
Genome Stability ◽  
Molecular Mechanisms ◽  
Excision Repair ◽  
Protein Complexes ◽  
Alkylating Agents ◽  
Strand Break

The six Saccharomyces cerevisiae SLX genes were identified in a screen for factors required for the viability of cells lacking Sgs1, a member of the RecQ helicase family involved in processing stalled replisomes and in the maintenance of genome stability. The six SLX gene products form three distinct heterodimeric complexes, and all three have catalytic activity. Slx3–Slx2 (also known as Mus81–Mms4) and Slx1–Slx4 are both heterodimeric endonucleases with a marked specificity for branched replication fork-like DNA species, whereas Slx5–Slx8 is a SUMO (small ubiquitin-related modifier)-targeted E3 ubiquitin ligase. All three complexes play important, but distinct, roles in different aspects of the cellular response to DNA damage and perturbed DNA replication. Slx4 interacts physically not only with Slx1, but also with Rad1–Rad10 [XPF (xeroderma pigmentosum complementation group F)–ERCC1 (excision repair cross-complementing 1) in humans], another structure-specific endonuclease that participates in the repair of UV-induced DNA damage and in a subpathway of recombinational DNA DSB (double-strand break) repair. Curiously, Slx4 is essential for repair of DSBs by Rad1–Rad10, but is not required for repair of UV damage. Slx4 also promotes cellular resistance to DNA-alkylating agents that block the progression of replisomes during DNA replication, by facilitating the error-free mode of lesion bypass. This does not require Slx1 or Rad1–Rad10, and so Slx4 has several distinct roles in protecting genome stability. In the present article, I provide an overview of our current understanding of the cellular roles of the Slx proteins, paying particular attention to the advances that have been made in understanding the cellular roles of Slx4. In particular, protein–protein interactions and underlying molecular mechanisms are discussed and I draw attention to the many questions that have yet to be answered.

scholarly journals p21-Mediated Nuclear Retention of Cyclin B1-Cdk1 in Response to Genotoxic Stress

2004 ◽  
Vol 15 (9) ◽  
pp. 3965-3976 ◽  
Author(s):  
Fabienne Baus Charrier-Savournin ◽  
Marie-Thérèse Château ◽  
Véronique Gire ◽  
John Sedivy ◽  
Jacques Piette ◽  
...  
Keyword(s):  
Dna Damage ◽  
Current Model ◽  
Human Fibroblasts ◽  
Genotoxic Stress ◽  
Cyclin B1 ◽  
Nuclear Accumulation ◽  
G2 Arrest ◽  
Nuclear Retention ◽  
Mitotic Cyclin ◽  
Normal Human

G2 arrest of cells suffering DNA damage in S phase is crucial to avoid their entry into mitosis, with the concomitant risks of oncogenic transformation. According to the current model, signals elicited by DNA damage prevent mitosis by inhibiting both activation and nuclear import of cyclin B1-Cdk1, a master mitotic regulator. We now show that normal human fibroblasts use additional mechanisms to block activation of cyclin B1-Cdk1. In these cells, exposure to nonrepairable DNA damage leads to nuclear accumulation of inactive cyclin B1-Cdk1 complexes. This nuclear retention, which strictly depends on association with endogenous p21, prevents activation of cyclin B1-Cdk1 by Cdc25 and Cdk-activating kinase as well as its recruitment to the centrosome. In p21-deficient normal human fibroblasts and immortal cell lines, cyclin B1 fails to accumulate in the nucleus and could be readily detected at the centrosome in response to DNA damage. Therefore, in normal cells, p21 exerts a dual role in mediating DNA damage-induced cell cycle arrest and exit before mitosis. In addition to blocking pRb phosphorylation, p21 directly prevents mitosis by inactivating and maintaining the inactive state of mitotic cyclin-Cdk complexes. This, with subsequent degradation of mitotic cyclins, further contributes to the establishment of a permanent G2 arrest.

The complex matter of DNA double-strand break detection

2003 ◽  
Vol 31 (1) ◽  
pp. 40-44 ◽  
Author(s):  
J.M. Bradbury ◽  
S.P. Jackson
Keyword(s):  
Dna Damage ◽  
Genome Stability ◽  
Strand Break ◽  
Damage Sensing ◽  
Dna Double Strand Break ◽  
Mre11 Complex ◽  
Damage Response ◽  
Radiation Induced ◽  
Dna Damage Signalling ◽  
Complex Matter

To maintain genomic stability, despite constant exposure to agents that damage DNA, eukaryotic cells have developed elaborate and highly conserved pathways of DNA damage sensing, signalling and repair. In this review, we concentrate mainly on what we know about DNA damage sensing with particular reference to Lcd1p, a yeast protein that functions early in DNA damage signalling, and MDC1 (mediator of DNA damage checkpoint 1), a recently identified human protein that may be involved in recruiting the MRE11 complex to radiation-induced nuclear foci. We describe a model for the DNA damage response in which factors are recruited sequentially to sites of DNA damage to form complexes that can amplify the original signal and propagate it to the multitude of response pathways necessary for genome stability.

scholarly journals Loss of BCL-3 sensitises colorectal cancer cells to DNA damage, revealing a role for BCL-3 in double strand break repair by homologous recombination

2021 ◽  
Author(s):  
Christopher Parker ◽  
Adam Christian Chambers ◽  
Dustin Flanagan ◽  
Tracey J Collard ◽  
Greg Ngo ◽  
...  
Keyword(s):  
Dna Damage ◽  
Homologous Recombination ◽  
Cellular Response ◽  
Parp Inhibitor ◽  
Strand Break ◽  
Double Strand Break ◽  
Parp Inhibition ◽  
Adjuvant Chemoradiotherapy ◽  
Wild Type ◽  
Γ Irradiation

Objective: The proto-oncogene BCL-3 is upregulated in a subset of colorectal cancers (CRC) and increased expression of the gene correlates with poor patient prognosis. The aim is to investigate whether inhibiting BCL-3 can increase the response to DNA damage in CRC.Design: The function of BCL-3 in DNA damage response was studied in vitro using siRNA and CRISPR-Cas9 genome editing and in vivo using Bcl3-/- mice. DNA damage induced by γ-irradiation and/or cisplatin was quantified using H2AX and RAD51 foci, repair pathways investigated using HR/NHEJ assays and treatment with the PARP inhibitor olaparib. Result: Suppression of BCL-3 increases double strand break number and decreases homologous recombination in CRC cells, supported by reduced RAD51 foci number and increased sensitivity to PARP inhibition. Importantly, a similar phenotype is seen in Bcl3-/-mice, where the intestinal crypts of these mice exhibit sensitivity to DNA damage and a greater number of double strand breaks compared to wild type mice. FurthermoreApc.Kras-mutant x Bcl3-/- mice exhibit increased DNA damage and reduced RAD51+ cells compared to their wild type counterparts when treated with cisplatin. Conclusion: This work identifies BCL-3 as a regulator of the cellular response to DNA damage and suggests that elevated BCL-3 expression could increase resistance of tumour cells to DNA damaging agents including radiotherapy. These findings offer a rationale for targeting BCL-3 in CRC as an adjuvant to conventional therapies and suggest that BCL-3 expression in tumours could be a useful biomarker in stratification of rectal cancer patients for neo-adjuvant chemoradiotherapy.

scholarly journals NLRP3 controls ATM activation in response to DNA damage

2020 ◽  
Author(s):  
Mélanie Bodnar-Wachtel ◽  
Anne-Laure Huber ◽  
Julie Gorry ◽  
Sabine Hacot ◽  
Laetitia Gerossier ◽  
...  
Keyword(s):  
Dna Damage ◽  
Cellular Response ◽  
Dna Double Strand Breaks ◽  
Functional Link ◽  
Atm Kinase ◽  
Damage Sensing ◽  
Pathway Activation ◽  
Genomic Stress ◽  
P53 Activation ◽  
Atm Signaling

ABSTRACTThe DNA damage response (DDR) is essential to preserve genomic integrity and acts as a barrier to cancer. The ATM pathway orchestrates the cellular response to DNA double strand breaks (DSBs), and its attenuation is frequent during tumorigenesis. Here, we show that NLRP3, a Pattern Recognition Receptor known for its role in the inflammasome complex formation, interacts with the ATM kinase to control the early phase of DDR, independently of its inflammasome activity. NLRP3 down-regulation in human bronchial epithelial cells impairs ATM pathway activation as shown by an altered ATM substrate phosphorylation profile, and due to impaired p53 activation, confers resistance to acute genomic stress. Moreover, we found that NLRP3 is down-regulated in Non-Small Cell Lung Cancer (NSCLC) tissues and NLRP3 expression is correlated with patient overall survival. NLRP3 re-expression in NSCLC cells restores appropriate ATM signaling. Our findings identify a non-immune function for NLRP3 in genome integrity surveillance and strengthen the concept of a functional link between innate immunity and DNA damage sensing pathways.

scholarly journals Role of P53 protein in activation of atm- and parp-mediated dna damage repair (DDR) pathways induced by topoisomerase type II inhibitors

2016 ◽  
Vol 97 (2) ◽  
pp. 245-249
Author(s):  
B R Ramazanov ◽  
R R Khusnutdinov ◽  
A R Galembikova ◽  
P D Dunaev ◽  
S V Boichuk
Keyword(s):  
Cell Cycle ◽  
Dna Damage ◽  
Cell Death ◽  
Cell Lines ◽  
Kinase Activity ◽  
P53 Protein ◽  
Human Fibroblasts ◽  
Repair System ◽  
Type Ii ◽  
Atm Kinase

Aim. To study the mechanisms of doxorubicin genotoxic effects in terms of poly-(ADP)-ribose-polymerase (PARP) and the ATM-kinase (Ataxia Telangiectasia Mutated) inhibition in cell lines with different p53 status.Methods. The study was conducted on BJ and BJp53DD human fibroblasts cell lines, cultured in DMEM medium supplemented with fetal bovine serum, L-glutamine and antibiotics. Inhibition of PARP and ATM-kinase activity was attained by adding synthetic inhibitors Nu1025 and Ku55933 respectively. Chemotherapy drug doxorubicin was used to induce deoxyribonucleic acid (DNA) damages. Cell viability analysis was performed using MTS-test. Repair system proteins and apoptotic markers expression was assessed by western blotting. Cells distribution by cell cycle phases was performed by flow cytometry.Results. Adding PARP and ATM-kinase inhibitors to the BJ p53DD cell line culture resulted in a significant reduction in the viable cells number amid DNA damage induction caused by doxorubicin. Cell death in these samples occurs according to the apoptosis mechanism, what was confirmed by the increase in hypodiploid cells number and increased expression of cleaved forms of PARP-1 and caspase-3. The above-described effects of the type II topoisomerase inhibitor doxorubicin were significantly higher in BJ fibroblasts line with non-functional p53 protein (p53DD) compared with conventional BJ human fibroblasts line.Conclusion. In the context of the failure of p53-dependent mechanisms of cell cycle regulation in BJ p53DD human fibroblasts, PARP and ATM-kinase activity inhibition leads to increased cell death by apoptosis mechanism induced by the doxorubicin action.

scholarly journals Modeling Cancer Genomic Data in Yeast Reveals Selection Against ATM Function During Tumorigenesis

2019 ◽  
Author(s):  
Marcel Hohl ◽  
Aditya Mojumdar ◽  
Sarem Hailemariam ◽  
Vitaly Kuryavyi ◽  
Fiorella Ghisays ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Tumor Suppression ◽  
Chromosome Instability ◽  
Genomic Data ◽  
Major Axis ◽  
Strand Break ◽  
Cancer Center ◽  
Mre11 Complex

AbstractThe DNA damage response (DDR) comprises multiple functions that collectively preserve genomic integrity and suppress tumorigenesis. The Mre11 complex and ATM govern a major axis of the DDR and several lines of evidence implicate that axis in tumor suppression. Components of the Mre11 complex are mutated in approximately five percent of human cancers. Inherited mutations of complex members cause severe chromosome instability syndromes, such as Nijmegen Breakage Syndrome, which is associated with strong predisposition to malignancy. And in mice, Mre11 complex mutations are markedly more susceptible to oncogene-induced carcinogenesis. The complex is integral to all modes of double strand break (DSB) repair and is required for the activation of ATM to effect DNA damage signaling. To understand which functions of the Mre11 complex are important for tumor suppression, we undertook mining of cancer genomic data from the clinical sequencing program at Memorial Sloan Kettering Cancer Center, which includes the Mre11 complex among the 468 genes assessed. Twenty five mutations in MRE11 and RAD50 were modeled in S.cerevisiae and in vitro. The mutations were chosen based on recurrence and conservation between human and yeast. We found that a significant fraction of tumor-borne RAD50 and MRE11 mutations exhibited separation of function phenotypes wherein Tel1/ATM activation was defective while DNA repair functions were mildly or not affected. At the molecular level, the gene products of RAD50 mutations exhibited defects in ATP binding and hydrolysis. The data reflect the importance of Rad50 ATPase activity for Tel1/ATM activation and suggest that inactivation of ATM signaling confers an advantage to burgeoning tumor cells.Author SummaryA complex network of functions is required for suppressing tumorigenesis. These include processes that regulate cell growth and differentiation, processes that repair damage to DNA and thereby prevent cancer promoting mutations and signaling pathways that lead to growth arrest and programmed cell death. The Mre11 complex influences both signaling and DNA repair. To understand its role in tumor suppression, we characterized mutations affecting members of the Mre11 complex that were uncovered through cancer genomic analyses. The data reveal that the signaling functions of the Mre11 complex are important for tumor suppression to a greater degree than its role in DNA repair.

Methods for Studying the Cellular Response to DNA Damage: Influence of the Mre11 Complex on Chromosome Metabolism

2006 ◽  
pp. 251-284 ◽  
Author(s):  
Jan‐Willem F. Theunissen ◽  
John H.J. Petrini
Keyword(s):  
Dna Damage ◽  
Cellular Response ◽  
Mre11 Complex

scholarly journals In Situ Visualization of Ultraviolet-Light-Induced DNA Damage Repair in Locally Irradiated Human Fibroblasts

2001 ◽  
Vol 117 (5) ◽  
pp. 1156-1161 ◽  
Author(s):  
Sachiko Katsumi ◽  
Nobuhiko Kobayashi ◽  
Kyoko Imoto ◽  
Akemi Nakagawa ◽  
Yukio Yamashina ◽  
...  
Keyword(s):  
Dna Damage ◽  
Ultraviolet Light ◽  
Human Fibroblasts ◽  
Dna Damage Repair ◽  
Damage Repair ◽  
In Situ Visualization
Sign in / Sign up

Export Citation Format

Share Document