Saccharomyces cerevisiae
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA100979 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Not many models of mammalian cell cycle system exist due to its complexity. Some models are too complex and hard to understand, while some others are too simple and not comprehensive enough. Moreover, some essential aspects, such as the response of G1-S and G2-M checkpoints to DNA damage as well as the growth factor signalling, have not been investigated from a systems point of view in current mammalian cell cycle models. To address these issues, we bring a holistic perspective to cell cycle by mathematically modelling it as a complex system consisting of important sub-systems that interact with each other. This retains the functionality of the system and provides a clearer interpretation to the processes within it while reducing the complexity in comprehending these processes. To achieve this, we first update a published ODE mathematical model of cell cycle with current knowledge. Then the part of the mathematical model relevant to each sub-system is shown separately in conjunction with a diagram of the sub-system as part of this representation. The model sub-systems are Growth Factor, DNA damage, G1-S, and G2-M checkpoint signalling. To further simplify the model and better explore the function of sub-systems, they are further divided into modules. Here we also add important new modules of: chk-related rapid cell cycle arrest, p53 modules expanded to seamlessly integrate with the rapid arrest module, Tyrosine phosphatase modules that activate Cyc_Cdk complexes and play a crucial role in rapid and delay arrest at both G1-S and G2-M, Tyrosine Kinase module that is important for inactivating nuclear transport of CycB_cdk1 through Wee1 to resist M phase entry, Plk1-Related module that is crucial in activating Tyrosine phosphatases and inactivating Tyrosine kinase, and APC-Related module to show steps in CycB degradation. This multi-level systems approach incorporating all known aspects of cell cycle allowed us to (i) study, through dynamic simulation of an ODE model, comprehensive details of cell cycle dynamics under normal and DNA damage conditions revealing the role and value of the added new modules and elements, (ii) assess, through a global sensitivity analysis, the most influential sub-systems, modules and parameters on system response, such as G1-S and G2-M transitions, and (iii) probe deeply into the relationship between DNA damage and cell cycle progression and test the biological evidence that G1-S is relatively inefficient in arresting damaged cells compared to G2-M checkpoint. To perform sensitivity analysis, Self-Organizing Map with Correlation Coefficient Analysis (SOMCCA) is developed which shows that Growth Factor and G1-S Checkpoint sub-systems and 13 parameters in the modules within them are crucial for G1-S and G2-M transitions. To study the relative efficiency of DNA damage checkpoints, a Checkpoint Efficiency Evaluator (CEE) is developed based on perturbation studies and statistical Type II error. Accordingly, cell cycle is about 96% efficient in arresting damaged cells with G2-M checkpoint being more efficient than G1-S. Further, both checkpoint systems are near perfect (98.6%) in passing healthy cells. Thus this study has shown the efficacy of the proposed systems approach to gain a better understanding of different aspects of mammalian cell cycle system separately and as an integrated system that will also be useful in investigating targeted therapy in future cancer treatments.
2018-12-13 | MODEL1812130001 | BioModels
Project description:Defects in DNA damage responses may underlie genetic instability and malignant progression in melanoma. Cultures of normal human melanocytes (NHMs) and melanoma lines were analyzed to determine whether global patterns of gene expression could predict the efficacy of DNA damage cell cycle checkpoints that arrest growth and suppress genetic instability. NHMs displayed effective G1 and G2 checkpoint responses to ionizing radiation-induced DNA damage. A majority of melanoma cell lines (11/16) displayed significant quantitative defects in one or both checkpoints. Melanomas with B-RAF mutations as a class displayed a significant defect in DNA damage G2 checkpoint function. In contrast the epithelial-like subtype of melanomas with wildtype N-RAS and B-RAF alleles displayed an effective G2 checkpoint but a significant defect in G1 checkpoint function. RNA expression profiling revealed that melanoma lines with defects in the DNA damage G1 checkpoint displayed reduced expression of p53 transcriptional targets, such as CDKN1A and DDB2, and enhanced expression of proliferation-associated genes, such as CDC7 and GEMININ. A Bayesian analysis tool was more accurate than significance analysis of microarrays for predicting checkpoint function using a leave-one-out method. The results suggest that defects in DNA damage checkpoints may be recognized in melanomas through analysis of gene expression. Experiment Overall Design: Normal human melanocyte and melanoma cell lines w/wo mutations in B-raf or N-ras were treated with 1.5 Gy IR irridiartion for G1 and G2 checkpoint determination. RNA was isolated from exponentially growing cultures and applied for microarray hybridizaton with Agilent 44 K (G4112A) array.
2008-06-15 | E-GEOD-7469 | biostudies-arrayexpress
Project description:A network governing DNA integrity was identified in yeast by a global genetic analysis of synthetic fitness or lethality defect (SFL) interactions. Within this network, multiple functional modules or mini-pathways were defined according to their common patterns of global SFL interactions and available protein-protein interaction information. Modules or genes involved in DNA replication, DNA replication checkpoint signaling, and oxidative stress response were identified as the major guardians against lethal spontaneous DNA damage, efficient repair of which requires the functions of the DNA damage checkpoint signaling and multiple DNA repair pathways. This genome-wide genetic interaction network also revealed potential roles of a number of genes and modules in mitotic DNA replication and maintenance of genomic stability. These include DIA2, NPT1, HST3, HST4, and the CSM1/LRS4 module (CSM1m). Likewise, the CTF18 module (CTF18m), previously implicated in sister chromatid cohesion, was found to participate in the DNA replication checkpoint. Keywords: dose response
2006-02-16 | GSE3574 | GEO
Project description:Cell cycle sensing of oxidative stress in Saccharomyces cerevisiae by oxidation of a specific cysteine residue in the transcription factor Swi6p. Yeast cells begin to bud and enter S phase when growth conditions are favourable during G1 phase. When subjected to oxidative stress, cells arrest at G1 delaying entry into the cell cycle allowing repair of cellular damage. Hence, oxidative stress sensing is coordinated with the regulation of cell cycle. We identified a redox sensing cysteine residue in the cell-cycle regulator of Saccharomyces cerevisiae, Swi6p, at position 404. Mutation of Cys404 to alanine abolished the ability of the cells to arrest at G1 upon treatment by lipid hydroperoxide. By constructing a truncated form of Swi6p, the Cys404 residue was found to be oxidised when cells were subjected to the oxidant. Furthermore, microarray analysis revealed that mutation of Cys404 to alanine led to loss of suppression of G1-cyclins CLN1 and PCL1 when the cells were exposed to lipid hydroperoxide. In conclusion, oxidation of Cys404 serves as a molecular sensor of oxidative stress and inhibits entry into the cell cycle by suppression of G1-cyclin expression.
2011-01-31 | GSE18334 | GEO
Project description:In the yeast Saccharomyces cerevisiae, cleavage factor I (CFI) and cleavage and polyadenylation factor (CPF) build the core of the transcription termination machinery. CFI comprises the Rna14, Rna15, Pcf11, and Clp1 proteins, as well as the associated Hrp5 RNA-binding protein. We found that CFI participates in the DNA damage response and that rna14-1 shows synthetic growth defects with mutants of different repair pathways, including homologous recombination, non-homologous end joining, post replicative repair, mismatch repair, and nucleotide excision repair, implicating that impaired RNAPII termination and 3â-end processing decreases the cellular tolerance for DNA damage. Beyond replication progression defects, we found that bypass of the G1/S checkpoint in rna14-1 cells leads to synthetic sickness, accumulation of phosphorylated H2A, as well as increase in Rad52-foci and in recombination. Our data provide evidence that CFI dysfunction impairs RNAPII turnover, leading to replication hindrance and lower tolerance to exogenous DNA damage. These findings underscore the importance of coordination between transcription termination, DNA repair and replication in the maintenance of genomic stability. S. cerevisiae strains were grown in YPAD liquid culture at 30°C, total RNA was isolated and hybridized on Affymetrix microarrays.
2014-03-31 | E-GEOD-50947 | biostudies-arrayexpress
Project description:Regulation of the DNA damage response and cell cycle progression is critical for maintaining genome integrity. Here we report that in response to DNA damage, COPS5 deubiquitinates and stabilizes PEA15 in an ATM kinase-dependent manner. PEA15 expression oscillates throughout the cell cycle, and the loss of PEA15 accelerates cell cycle progression by activating CDK6 expression via the c-JUN transcription factor. Cells lacking PEA15 exhibit a DNA damage-induced G2/M checkpoint defect due to increased CDC25C activity and consequentially higher CDK1/Cyclin B activity and accordingly have an increased rate of spontaneous mutagenesis. We find that oncogenic RAS inhibits PEA15 expression and ectopic PEA15 expression blocks RAS-mediated transformation, which can be partially rescued by ectopic expression of CDK6. Finally, we show that PEA15 expression is down regulated in colon, breast and lung cancer samples. Collectively, our results demonstrate that tumor suppressor PEA15 is a regulator of genome integrity and is an integral component of the DNA damage response pathway that regulates cell cycle progression, the DNA-damage-induced G2/M checkpoint and cellular transformation. HCT116 cells stably expressing a non-silencing shRNA or two individual shRNAs against PEA15 were used to prepare the total RNA, which was then used to analyze for gene expression using Illumina expression array.
2014-04-07 | E-GEOD-39297 | biostudies-arrayexpress
Project description:DNA damage checkpoint kinases regulate a global network of transcription factors
| PRJNA173726 | ENA
Project description:DNA replication forks that are stalled by DNA damage activate an S phase checkpoint that prevents irreversible fork arrest and cell death. The increased cell death caused by DNA damage in budding yeast cells lacking the Rad53 checkpoint protein kinase is partially suppressed by deletion of the EXO1 gene. Here,we identified that loss of the histone deacetylase complex Rpd3L promotes survival of rad53∆ cells exposed to DNA damaging agents. From epistasis analysis, we show that this suppression operates in a separate pathway from the previously described suppression by deletion of EXO1.
2019-02-27 | GSE113869 | GEO
Project description:In the yeast Saccharomyces cerevisiae, cleavage factor I (CFI) and cleavage and polyadenylation factor (CPF) build the core of the transcription termination machinery. CFI comprises the Rna14, Rna15, Pcf11, and Clp1 proteins, as well as the associated Hrp5 RNA-binding protein. We found that CFI participates in the DNA damage response and that rna14-1 shows synthetic growth defects with mutants of different repair pathways, including homologous recombination, non-homologous end joining, post replicative repair, mismatch repair, and nucleotide excision repair, implicating that impaired RNAPII termination and 3’-end processing decreases the cellular tolerance for DNA damage. Beyond replication progression defects, we found that bypass of the G1/S checkpoint in rna14-1 cells leads to synthetic sickness, accumulation of phosphorylated H2A, as well as increase in Rad52-foci and in recombination. Our data provide evidence that CFI dysfunction impairs RNAPII turnover, leading to replication hindrance and lower tolerance to exogenous DNA damage. These findings underscore the importance of coordination between transcription termination, DNA repair and replication in the maintenance of genomic stability.
2014-03-31 | GSE50947 | GEO
Project description:Heldt2018 - Proliferation-quiescence decision
in response to DNA damage
This model is described in the article:
A comprehensive model for
the proliferation-quiescence decision in response to endogenous
DNA damage in human cells.
Heldt FS, Barr AR, Cooper S, Bakal
C, Novák B.
Proc. Natl. Acad. Sci. U.S.A. 2018 Feb;
:
Abstract:
Human cells that suffer mild DNA damage can enter a
reversible state of growth arrest known as quiescence. This
decision to temporarily exit the cell cycle is essential to
prevent the propagation of mutations, and most cancer cells
harbor defects in the underlying control system. Here we
present a mechanistic mathematical model to study the
proliferation-quiescence decision in nontransformed human
cells. We show that two bistable switches, the restriction
point (RP) and the G1/S transition, mediate this decision by
integrating DNA damage and mitogen signals. In particular, our
data suggest that the cyclin-dependent kinase inhibitor p21
(Cip1/Waf1), which is expressed in response to DNA damage,
promotes quiescence by blocking positive feedback loops that
facilitate G1 progression downstream of serum stimulation.
Intriguingly, cells exploit bistability in the RP to convert
graded p21 and mitogen signals into an all-or-nothing
cell-cycle response. The same mechanism creates a window of
opportunity where G1 cells that have passed the RP can revert
to quiescence if exposed to DNA damage. We present experimental
evidence that cells gradually lose this ability to revert to
quiescence as they progress through G1 and that the onset of
rapid p21 degradation at the G1/S transition prevents this
response altogether, insulating S phase from mild, endogenous
DNA damage. Thus, two bistable switches conspire in the early
cell cycle to provide both sensitivity and robustness to
external stimuli.
This model is hosted on
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MODEL1703030000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
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2024-09-02 | BIOMD0000000700 | BioModels