Genome wide mapping of DNA lesions by Repair Assisted Damage Detection sequencing – RADD-Seq
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE166843 | GEO | 2021/02/17
REPOSITORIES: GEO
Similar Datasets
Project description:Protecting the integrity of their genome is critical to all species. The surveillance and maintenance of the genome of every organism is orchestrated by a highly regulated combination of DNA damage response and specific DNA repair pathways. Two of these critical pathways are base excision repair (BER) and ribonucleotide excision repair (RER). Here, we investigate the phylogenetic diversity in the recognition and repair of three well-established DNA lesions, primarily repaired by BER or RER: 1) 8-oxoguanine, 2) an abasic site, and 3) incorporated ribonucleotide in DNA in E. coli, B. subtilis, H. salinarum, T. brucei, T. thermophila, S. cerevisiae, S. pombe, C. elegans, human HeLa and HEK293 cells, A. thaliana, and Z. mays. Using quantitative mass spectrometry, we identified 337 enriched interactors across these species. Of these proteins, 140 were previously characterized to be involved in DNA repair, and 39 proteins were newly identified due to their homology to previously studied repair proteins. For 10 of the 11 species, we identify unique, uncharacterized proteins that lack homology to any protein within the included 11 species. Our study emphasizes strong crosstalk between RER and BER and highlights the evolutionary conservation of this cross recognition across all domains of life.
2023-07-20 | PXD036040 | Pride
Project description:Comprehensive Model Description
Overview
This model simulates the cellular response to DNA damage under conditions of ATM/ATR deficiency—such as in ataxia telangiectasia—and predicts the potential benefits of drug repositioning with Omaveloxolone and spermidine. It integrates several interconnected modules: DNA damage production and repair, ATM/ATR–p53 signaling, NRF2/KEAP1 regulation, spermidine-induced autophagy (with additional positive modulation of ATR signaling), and downstream p53 effectors involved in cell fate decisions.
1. DNA Damage Production and Repair Module
Basal DNA Damage Production:
DNA damage is continuously generated at a constant rate, representing both endogenous processes and low-level environmental stress. This reaction acts as a source term for the DNA_damage species.
Repair Pathways:
Several mechanisms work to reduce DNA damage:
ATM-Mediated Repair: Active ATM facilitates the direct repair of DNA damage.
ATR-Mediated Repair: Active ATR, in cooperation with CHK1, repairs DNA damage.
NRF2-Mediated Repair: Active NRF2 triggers antioxidant responses that reduce DNA damage.
Autophagy-Mediated Repair: The autophagy pathway, induced by spermidine, repairs DNA damage in a saturable manner (modeled using Michaelis–Menten kinetics). This ensures that even a significant pulse of damage is only partially repaired, leaving a nonzero steady-state level.
2. ATM/ATR–p53 Signaling Module
ATM and ATR Activation:
DNA damage, along with a positive input from TOPBP1, converts inactive ATM and ATR to their active forms. Under ATM/ATR-deficient conditions (as in ataxia telangiectasia), the activation is severely reduced, resulting in higher levels of unrepaired DNA damage.
p53 Activation:
Both ATM_active and ATR_active phosphorylate and activate p53. Active p53 then acts as a central integrator of the DNA damage signal.
Regulatory Proteins:
HDAC4:
HDAC4 cycles between inactive and active states. Its active form can attenuate p53 activity.
TOPBP1:
TOPBP1 is activated in a DNA damage–dependent manner and helps promote ATR activation.
CK2:
CK2 is a constitutively active kinase that supports TOPBP1 activation.
3. NRF2/KEAP1 Module and Omaveloxolone
NRF2 Activation:
DNA damage stimulates the conversion of NRF2_inactive to NRF2_active. Active NRF2 enhances antioxidant defenses and promotes DNA repair.
KEAP1-Mediated Degradation:
Under normal conditions, KEAP1 targets NRF2_inactive for degradation, keeping NRF2 activity low.
Modulation by Omaveloxolone:
Omaveloxolone is modeled as a constant (boundary) species. It inhibits KEAP1’s activity, thereby reducing NRF2 degradation. This shifts the balance in favor of increased NRF2_active, which boosts the cell’s antioxidant and repair responses.
4. Spermidine-Induced Autophagy and Positive Modulation of ATR Signaling
Spermidine is modeled as a constant species and has two major effects:
Induction of Autophagy:
Spermidine promotes the conversion of Autophagy_inactive to Autophagy_active. The active autophagy machinery repairs DNA damage using a saturable (Michaelis–Menten) mechanism. This pathway helps clear DNA damage but is limited by its maximum capacity.
Enhancement of ATR Signaling:
Spermidine also positively modulates ATR signaling by enhancing the CK2-mediated activation of TOPBP1. In the model, the effective rate of TOPBP1 activation is increased proportionally to the concentration of spermidine. This is represented by a modulation factor, where the effective rate constant for TOPBP1 activation is multiplied by a term that increases with spermidine concentration. The boosted TOPBP1_active level in turn enhances ATR activation, partially compensating for the loss of ATM/ATR function.
5. Downstream p53 Targets: Cell Fate Decisions
Activated p53 regulates cell fate by inducing the production of several downstream effectors:
p21:
p21 is produced in response to p53 activation and is associated with cell cycle arrest and senescence. Its production is balanced by a degradation reaction.
BAX and PUMA:
Both BAX and PUMA are pro-apoptotic proteins. They are produced in proportion to p53_active and are subsequently degraded. Their relative levels help determine whether the cell will undergo apoptosis.
6. Reaction Kinetics (Qualitative Overview)
Mass-Action and Michaelis–Menten Kinetics:
Most reactions in the model are governed by mass-action kinetics. For example, activation and deactivation reactions (such as ATM activation by DNA damage or p53 activation by ATM/ATR) follow simple proportional relationships.
Saturable Repair Processes:
The autophagy-mediated DNA repair reaction uses Michaelis–Menten kinetics to reflect a saturation effect; when DNA damage is high, the repair rate approaches a maximum value, ensuring that not all damage is cleared immediately.
Modulatory Effects:
Spermidine increases the effective rate of TOPBP1 activation (and hence ATR activation) via a modulation term that is proportional to its concentration. Omaveloxolone reduces the degradation rate of NRF2 by inhibiting KEAP1.
Biological Implications and Model Utility
ATM/ATR Deficiency:
In ataxia telangiectasia, ATM/ATR functions are diminished, leading to increased DNA damage. The model simulates this scenario and examines how alternative pathways (NRF2-mediated repair, autophagy, and enhanced ATR signaling via spermidine) help mitigate the damage.
Drug Repositioning Predictions:
The model can be used to predict the outcomes of repositioning drugs:
Omaveloxolone is expected to stabilize NRF2, enhancing antioxidant defenses and reducing DNA damage.
Spermidine acts dually by promoting autophagy (with a saturable repair capacity) and by boosting ATR signaling via TOPBP1 activation.
Cell Fate Outcomes:
The downstream p53 targets (p21, BAX, and PUMA) serve as markers for cell cycle arrest/senescence and apoptosis. By simulating the dynamics of these proteins, the model can predict whether a cell is likely to survive, arrest its cycle, or undergo apoptosis based on the integrated response to DNA damage and drug interventions.
Conclusion
This detailed and comprehensive model integrates multiple layers of the cellular response to DNA damage in ATM/ATR-deficient conditions. It includes upstream damage sensing, multiple repair pathways (including direct kinase-mediated repair, antioxidant responses via NRF2, and autophagy-mediated repair), and downstream effectors that determine cell fate. Omaveloxolone and spermidine are modeled to specifically modulate the NRF2/KEAP1 pathway and ATR signaling (via TOPBP1 activation), respectively. This framework provides a robust platform for exploring drug repositioning strategies and predicting cellular outcomes in diseases such as ataxia telangiectasia.
2025-11-25 | MODEL2503190002 | BioModels
Project description:Altered oncogene expression in cancer cells causes loss of redox homeostasis resulting in oxidative DNA damage, e.g., 8-oxoguanine (8-oxoG), repaired by base excision repair (BER). PARP1 coordinates BER and relies on the upstream 8-oxoguanine-DNA glycosylase (OGG1) to recognise and excise 8-oxoG. Here we hypothesize that OGG1 may represent an attractive target to exploit reactive oxygen species (ROS) elevation in cancer. Although OGG1 depletion is well tolerated in non-transformed cells, we report here that OGG1 depletion obstructs A3 T-cell lymphoblastic acute leukemia growth in vitro and in vivo, validating OGG1 as a potential anti- cancer target. In line with this hypothesis, we show that OGG1 inhibitors (OGG1i) target a wide range of cancer cells, with a favourable therapeutic index compared to non-transformed cells. Mechanistically, OGG1i and shRNA depletion cause lost mitochondrial function leading to S- phase DNA damage, replication stress and proliferation arrest or cell death, representing a novel mechanistic approach to target cancer. This study adds OGG1 to the list of BER factors, e.g., PARP1, as potential targets for cancer treatment. _x000B_
2020-08-07 | GSE155782 | GEO
Project description:Shells of pearl oyster are natural biominerals with remarkable properties and can be repaired after damage, which are regulated by biomacromolcules especially shell matrix proteins (SMPs). Identifying SMPs is critical for further understanding the process. Although proteomic methods have been used to reveal the complex protein mixture in mature shells, the proteomics of repaired shells after shell damage have not been reported before. Here, we studied the SMPs of the repaired shells (prismatic layers) 5-10 days after shell damage in Pinctada fucata by integrating transcriptomics and proteomics and compared the microstructure difference between repaired and mature shells. Although the repaired shells are calcite, similar to mature shells, the microstructure of repaired shells has holes in the center of prisms with irregular and curved edges. In total, we found 49 SMPs from the repaired shells including some proteins only existing in mature nacreous layers. Peroxidase-like protein and beta-N-acetylhexosaminidase may be important players in repaired shells. In addition, they have the capability to affect CaCO3 crystallization process in vitro, altering the packing and reducing the crystallinity of crystals. This study could improve our understanding of shell repair process and lay the foundation for studying SMPs-controlled biomineralization.
2019-03-26 | PXD010130 | Pride
Project description:UV-induced DNA damage is the major carcinogen of skin cancer. We developed HS-Damage-seq to map UV damage with unprecedented sensitivity and resolution in human cells. While the distribution of UV-induced damage are mainly determined by sequence context and essentially uniform throughout the genome, transcription factors can affect damage formation at specific positions. With time-course experiments, we observed changes in damage distribution at particular genomic loci and chromatin states, which reflects the nucleotide excision repair preferences and complements the repair maps by XR-seq. Our results demonstrated that while initial damage is uniformly distributed, they are heterogeneously repaired throughout the genome. The combination of damage and repair maps provides a holistic perspective of UV damage and repair in the human genome.
2017-06-27 | GSE98025 | GEO
Project description:Ultraviolet C radiation (UVC) damages the nuclear and mitochondrial genomes; this damage is repaired in the nuclear but not mitochondrial genome. Ethidium bromide (EtBr) inhibits mitochondrial DNA replication. We were interested in the transcriptomic response to exposure to UVC, EtBr, and the combination. The UVC exposure protocol results in a high level of mitochondrial DNA damage, and a low level of nuclear DNA damage (because of repair).
2012-10-01 | GSE38997 | GEO
Project description:Critical DNA repair pathways become deranged during cancer development. This vulnerability may be exploited with DNA-targeting chemotherapy. Topoisomerase II inhibitors induce double-strand breaks which are detrimental to the cell, if not repaired. This repair process requires high-fidelity functional homologous recombination or error-prone non-homologous recombination. If either of these pathways is targeted, the compensatory pathway may rescue the cells and induce treatment resistance. c-Abl is a protein tyrosine kinase that is involved in cell differentiation, cell division, cell adhesion, and stress response including DNA damage induced stress. Here we used a low dose topoisomerase II inhibitor mitoxantrone to induce DNA damage and c-Abl kinase inhibitor imatinib in combination and studied the drug effects at transcriptomic level. The microarray data suggests that DNA repair, particularly homologous recombination, is downregulated together with alterations in cell cycle regulation. The data prompted to further validation assays on functional level which are shown in the original publication.
2021-09-22 | E-MTAB-9475 | biostudies-arrayexpress
Project description:Ultraviolet C radiation (UVC) damages the nuclear and mitochondrial genomes; this damage is repaired in the nuclear but not mitochondrial genome. Ethidium bromide (EtBr) inhibits mitochondrial DNA replication. We were interested in the transcriptomic response to exposure to UVC, EtBr, and the combination. The UVC exposure protocol results in a high level of mitochondrial DNA damage, and a low level of nuclear DNA damage (because of repair). We exposed age-matched L1-stage Caenorhabditis elegans to ultraviolet C radiation (UVC ) three times, separated in time by 24 h, in the absence of food. After the third exposure, larvae were placed on K agar plates with OP50 bacterial food. In some cases ethidium bromide was also used. Nematodes were sampled for RNA isolation several times.
2012-10-01 | E-GEOD-38997 | biostudies-arrayexpress
Project description:Skin exposure to ultraviolet (UV) rays from sunlight results in the formation of mutagenic DNA photolesions that are repaired by the nucleotide excision repair (NER) machinery. The inefficient repair of photolesions can lead to stalled DNA replication and mispairing, thereby causing strand breaks and mutations. B-cell translocation gene 3 (BTG3) is expressed in the epidermis of the skin and is an antiproliferative gene that is upregulated in human keratinocytes after radiation injury. In this study, we found that BTG3 is required to promote the timely extraction of the lesion-binding protein XPC by the segregase VCP/p97, an essential step preceding the excision of photolesions. Mechanistically, we showed that BTG3-dependent CHK1 activation and phosphorylation of VCP/p97 at S775 are necessary for the nuclear translocation of VCP/p97 after UV irradiation. Thus, loss of BTG3 or inhibition of CHK1 results in cytoplasmic retention of VCP/p97 and accumulation of ubiquitinated XPC, leading to delayed removal of photolesions and inefficient NER, which was recapitulated in vivo in the skin of the Btg3 knockout mice showing increased photolesions and H2AX and elevated mutations after UV. Our findings revealed that by influencing the cellular localization of VCP/p97, BTG3 is critical for the proper execution of NER to protect cells from UV-induced damage and skin carcinogenesis.
2025-07-14 | PXD056446 | Pride
Project description:Skin pigmentation is paused following sun exposure, however the mechanism behind this pausing is unknown. Here we found that the UVB-induced DNA repair system, led by the ATM protein kinase, represses MITF transcriptional activity of pigmentation genes while placing MITF in DNA repair mode, thus directly inhibiting pigment production. Phosphoproteomics analysis revealed ATM to be the most significantly enriched pathway among all UVB-induced DNA repair systems. ATM inhibition in mouse or human skin, either genetically or chemically, induces pigmentation. Upon UVB, MITF transcriptional activation is blocked due to ATM dependent phosphorylation of MITF on S414, which modifies MITF activity and interactome towards DNA repair including binding to TRIM28 and RBBP4. Accordingly, MITF genome-occupancy is enriched in sites of high DNA damage that are likely repaired. This suggests that ATM harnesses the pigmentation key activator, for the necessary rapid, efficient DNA repair, thus optimizing the chances of the cell to survive.
2023-07-19 | PXD041121 | Pride