DNA damage checkpoint kinases regulate a global network of transcription factors
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ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
SUBMITTER: Dwight Kuo
PROVIDER: E-GEOD-40351 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:DNA damage results in the activation of checkpoint kinases, which phosphorylate downstream effectors that inhibit the cell cycle, activate DNA repair, and cause widespread changes in transcription. However, the specific connections between the checkpoint kinases and downstream transcription factors (TFs) are not well understood. Here, we introduce a strategy for mapping regulatory networks between kinases and TFs involving integration of kinase mutant expression profiles, transcriptional regulatory interactions, and phosphoproteomics. We use this approach to investigate the role of the Saccharomyces cerevisiae checkpoint kinases (Mec1, Tel1, Chk1, Rad53, and Dun1) in the transcriptional response to DNA damage caused by methyl methanesulfonate (MMS). The result is a global kinase-TF regulatory network in which Mec1 and Tel1 signal through Rad53 to synergistically regulate the expression of more than 600 genes. This network implicates at least nine TFs, including Msn4, Gcn4, SBF (Swi4/Swi6), MBF (Swi6/Mbp1), and Fkh2/Ndd1/Mcm1, nearly all of which have sites of Rad53-dependent phosphorylation, as downstream regulators of checkpoint kinase-dependent genes. We also identify a major DNA damage-induced transcriptional network acting independently of Rad53 and other checkpoint kinases to regulate expression of genes involved in general and oxidative stress responses.
2013-03-31 | GSE40351 | GEO
Project description:The cohesin complex holds together newly-replicated chromatids and is involved in diverse pathways that preserve genome integrity. We show that in budding yeast, cohesin is transiently recruited to active replication origins and it spreads along DNA as forks progress. When DNA synthesis is impeded, cohesin accumulates at replication sites and is critical for the recovery of stalled forks. Cohesin enrichment at replication forks does not depend on H2A(X) formation, which differs from its loading requirements at DNA double-strand breaks (DSBs). However, cohesin localization is largely reduced in rad50delta mutants and cells lacking both Mec1 and Tel1 checkpoint kinases. Interestingly, cohesin loading at replication sites depends on the structural features of Rad50 that are important for bridging sister chromatids, including the CXXC hook domain and the length of the coiled-coil extensions. Together, these data reveal a novel function for cohesin in the maintenance of genome integrity during S phase. Scc1 ChIP, Rad50 ChIP and BrdU IP in wild type and mutants at different stages of the cell cycle.
2012-10-01 | E-GEOD-39078 | biostudies-arrayexpress
Project description:In Saccharomyces cerevisiae, Elevated Levels of Aneuploidy and Chromosome Rearrangements are Separable Genome Instability Events Controlled by the Tel1 and Mec1 Kinases Cancer cells often have elevated frequencies of chromosomal aberrations, and it is likely that loss of genome stability is one driving force behind tumorigenesis. Deficiencies in DNA replication, DNA repair, or cell cycle checkpoints can all contribute to increased rates of chromosomal duplications, deletions and translocations. The Saccharomyces cerevisiae proteins Tel1 and Mec1 (homologues of the human ATM and ATR proteins, respectively) are known to participate in the DNA damage response, replication checkpoint, and telomere maintenance pathways and are critical to maintain genome stability. In the absence of induced DNA damage, tel1 mec1 diploid yeast strains exhibit extremely high rates of chromosome aneuploidy. There is a significant bias towards trisomy of chromosomes II, VIII, X, and XII, whereas the smallest chromosomes I and VI are commonly monosomic. tel1 mec1 strains also demonstrate elevated levels of chromosome rearrangements, including translocations as well as interstitial duplications and deletions. Restoring wild-type telomere length with the Cdc13-Est2 fusion protein substantially reduces the amount of chromosome rearrangements in tel1 mec1 strains. This result suggests that most of the rearrangements are initiated by telomere-telomere fusions. However, the telomere defects associated with tel1 mec1 strains do not cause the high rate of aneuploidy, as restoring proper telomere function does not prevent cells from becoming aneuploid. Our data demonstrate that the same mutant genotype can produce both high levels of chromosome rearrangements and high levels of aneuploidy, and these two types of events occur through separate mechanisms.
2009-09-03 | GSE17903 | GEO
Project description:Checkpoints are cellular surveillance and signaling pathways that regulate responses to DNA damage and perturbations of DNA replication. Here we show that high levels of sumoylated Rad52 are present in the mec1 sml1 and rad53 sml1 checkpoint mutants exposed to DNA damaging agents such as methyl methanesulfonate (MMS) or the DNA replication inhibitor hydroxyurea (HU). The kinase-defective mutant rad53-K227A also showed high levels of Rad52 sumoylation. Elevated levels of Rad52 sumoylation occur in checkpoint mutants proceeding S phase being exposed DNA-damaging agent. Interestingly, ChIP on chip analyses revealed non-canonical chromosomal localization of Rad52 in the HU-treated rad53-K227A cells arrested in early S phase: Rad52 localization at dormant and early DNA replication origins. However, such unusual localization was not dependent on the sumoylation of Rad52. In addition, we also found that Rad52 could be highly sumoylated in the absence of Rad51. Double deletion of RAD51 and RAD53 exhibited the similar levels of Rad52 sumoylation to RAD51 single deletion. The significance and regulation mechanism of Rad52 sumoylation by checkpoint pathways will be discussed. Keywords: ChIP-chip
2009-05-26 | GSE14761 | GEO
Project description:The Mec1/ATR kinase coordinates multiple cellular responses to replication stress. In addition to its canonical role in activating the checkpoint kinase Rad53, Mec1 also plays checkpoint-independent roles in genome maintenance that are not well understood. Here we employed a combined genetic-phosphoproteomic approach to manipulate Mec1 activation and globally monitor Mec1 signaling, allowing us to delineate distinct checkpoint-independent modes of Mec1 action. Using cells in which endogenous Mec1 activators were genetically ablated, we found that expression of “free” Mec1 Activation Domains (MADs) can robustly activate Mec1 and rescue the severe DNA replication and growth defects of these cells back to wild-type levels. However, unlike the activation mediated by endogenous activator-proteins, “free” MADs are unable to stimulate Mec1-mediated suppression of gross chromosomal rearrangements (GCRs), revealing that Mec1’s role in genome maintenance is separable from a previously unappreciated pro-replicative function. Both Mec1’s functions in promoting replication and suppressing GCRs are independent of the downstream checkpoint kinases. Additionally, Mec1-dependent GCR suppression seems to require localized Mec1 action at DNA lesions, which correlates with the phosphorylation of activator-proximal substrates involved in homologous recombination-mediated DNA repair. These findings establish that Mec1 initiates checkpoint signaling, promotes DNA replication, and maintains genetic stability through distinct modes of action.
2019-01-14 | PXD009734 | Pride
Project description:MBF and SBF transcription factors regulate a large family of coordinately expressed G1/S genes required for early cell cycle functions including DNA replication and repair. SBF is inactivated upon S phase entry by Clb/CDK whereas MBF targets are repressed by the corepressor, Nrm1. Using genome-wide expression analysis, we show that genotoxic stress during S phase specifically induces MBF-regulated genes via direct phosphorylation of Nrm1 by Rad53, the effector checkpoint kinase, and prevents its binding to MBF target promoters. Interestingly, some previously defined targets of SBF, including Swe1, are activated by replication stress. Swe1 undergoes a transcription factor exchange leading to its repression by Nrm1/MBF, which renders it sensitive to derepression by the S phase checkpoint. We conclude that MBF-regulated genes are distinguished from SBF-regulated genes by their sensitivity to activation by the S phase checkpoint, thereby, providing an effective mechanism for enhancing DNA replication and repair and promoting genome stability. Modified Loop Time-series design, time points at 0, 30, 45, 60 and 75 minutes. Conditions are untreated (UT), methyl methane sulfonate (MMS-0.033%), camptothecin (CPT-50uM), and hydroxyurea (HU-0.2M)
2012-02-15 | E-GEOD-33695 | biostudies-arrayexpress
Project description:Maintenance of genetic integrity is essential for survival of all organisms. Activating transcription factor 3 (ATF3) is a member of the c-AMP response element binding (CREB)/ATF family of transcription factors, and is highly inducible by various stress conditions including DNA damage. However, downstream targets and molecular basis underlying pleiotropic effects of ATF3 on the cell fate have been largely unknown. To identify ATF3 targets in the human genome, we carried out chromatin immunoprecipitation-microarray (ChiP-on-chip) and knockdown-expression profiling analysis using two models where ATF3 was either transiently induced or constitutively expressed. We show that ATF3 binds to an unexpectedly large number of targets; 5,984 promoters in HCT116 cells treated with an alkylating agene methyl methanesulfonate (MMS) and 1,423 promoters in LNCaP cells constitutively expressing ATF3. Importantly, targets of MMS-induced ATF3 are highly enriched not only for CREB/ATF motifs but also for binding sites of several stress sensors including DDIT3/CHOP, Egr1, and c-Ets which are concomitantly induced by MMS. Stress-induced ATF3 affects broad but select biological processes including cell cycle, cell death, adhesion, biosynthesis, and receptor signaling pathways. In addition, ATF3 binds to as many as 40% of the p53 targets and preferentially enhances MMS-induced activation of proapoptotic genes such as DR4, DR5, and PUMA, consistent with the proapoptotic effect of ATF3. These data shed new light on the co-regulatory function of ATF3 in the stress-induced transcription factor network. The comprehensive list of genomic targets of ATF3 will facilitate further understanding the role of ATF3 in determining life and death of cells under both physiological and tumour-associated stress conditions. Maintenance of genetic integrity is fundamental to survival of all organisms. DNA damage can be caused by various agents in environment and elicits complex responses in the cell. ATF3 is one of the transcription factors activated by various stress conditions including DNA damage, and has been shown to have pleiotropic effects on life and death of cells depending on the context of experimental conditions. It has been largely unknown, however, which genes and pathways are regulated by stress-induced ATF3. Here we attempted to answer this question by chromatin immunoprecipitation-microarray analysis of downstream targets of ATF3. We show that ATF3 binds to an unexpectedly large number of promoters (nearly 6,000) in a human colorectal cancer cell lineHCT116 treated with an alkylating agent methyl methanesulfonate. Interestingly, the ATF3 targets are highly enriched for binding sites of other stress sensors shedding light on a transcriptional co-regulatory network of DNA damage response. We further show that ATF3 regulates expression of genes in select biological processes including cell cycle, cell death, adhesion, metabolism, signal transduction, and the p53 pathway. The comprehensive list of ATF3 targets provides new insight into a highly inter-connected network of stress-induced transcription factors around ATF3. ChIP-chip samples: Comparison of ATF3-IP and whole genome DNA (control) Gene expression samples: HCT116 cells pre-transfected with either control siRNA or ATF3 knockdown siRNA and stimulated by methyl methanesulfonate (MMS) for 0, 6, 12, and 24 hours
2010-10-01 | E-GEOD-18457 | biostudies-arrayexpress
Project description:In Saccharomyces cerevisiae, a single double-strand break (DSB) triggers extensive phosphorylation of histone H2A (known as gammaH2AX) over 50 kb on either side of the DSB. This modification is carried out by either of yeastM-^Rs checkpoint kinases, the ATM homolog, Tel1, or the ATR homolog, Mec1. In G1-arrested cells, where there is very little 5M-^R to 3M-^R processing of DSB ends, only Tel1 promotes this modification. We have recently described a second modification gammaH2B - the phosphorylation of the C terminal T129 locus of histone H2B which is also carried out by both Mec1 and Tel1 kinases. To understand in detail how gamma-H2AX and gamma-H2B spread along the chromosome from a DSB we have undertaken a high-density analysis of their occupancy where there is a DSB on three different chromosomes. gamma-H2AX and gamma-H2B modifications are similar, but there is a marked absence of gamma-H2B near telomeres. We find that there is reduced gamma-H2AX and gamma-H2B modification over strongly transcribed regions, even taking into account the reduced histone occupancy of these genes. When transcription of the galactose-regulated genes GAL1, GAL10, GAL7 are turned off by the addition of glucose, gamma-H2AX is restored within 5 min; when these genes are again induced, gamma-H2AX is rapidly lost. Regions more distal to the GAL genes have markedly reduced gamma-H2AX levels that rise rapidly when transcription is repressed, suggesting that transcription acts as a barrier to the propagation of gamma-H2AX away from the DSB. The restoration of gamma-H2AX in transcribed regions can be carried out by either Mec1 or Tel1, even 7 h after break induction, suggesting that Tel1 remains associated with damaged chromosomes for an extended time. In addition, we show that gamma-H2AX can be transferred in trans, to regions unlinked to the DSB that lie in close proximity the DSB. Specifically, if a DSB is generated 14 kb from CEN2, gamma-H2AX is transferred to regions around all the other centromeres, in keeping with observed close proximity of all centromere-adjacent chromosome arms. This transfer can be observed even in the absence of formaldehyde crosslinking of the samples.
2013-12-15 | E-MTAB-1409 | biostudies-arrayexpress
Project description:Checkpoints are cellular surveillance and signaling pathways that regulate responses to DNA damage and perturbations of DNA replication. Here we show that high levels of sumoylated Rad52 are present in the mec1 sml1 and rad53 sml1 checkpoint mutants exposed to DNA damaging agents such as methyl methanesulfonate (MMS) or the DNA replication inhibitor hydroxyurea (HU). The kinase-defective mutant rad53-K227A also showed high levels of Rad52 sumoylation. Elevated levels of Rad52 sumoylation occur in checkpoint mutants proceeding S phase being exposed DNA-damaging agent. Interestingly, ChIP on chip analyses revealed non-canonical chromosomal localization of Rad52 in the HU-treated rad53-K227A cells arrested in early S phase: Rad52 localization at dormant and early DNA replication origins. However, such unusual localization was not dependent on the sumoylation of Rad52. In addition, we also found that Rad52 could be highly sumoylated in the absence of Rad51. Double deletion of RAD51 and RAD53 exhibited the similar levels of Rad52 sumoylation to RAD51 single deletion. The significance and regulation mechanism of Rad52 sumoylation by checkpoint pathways will be discussed. Keywords: ChIP-chip ⢠The goal of the experiment Genome-wide localization of Rad52 binding sites in Saccharomyces cerevisiae ⢠Experimental factor Distribution of Rad52 on chromosome III, IV, and V and the right arm of chromosome VI Strain: wild type, rad53 mutant, and rad53 siz2 mutant (W303 background, expressing myc tagged protein from its native promoter) Cell condition 1: G1 arrest with alpha-factor Cell condition 2: HU treatment ⢠Experimental design ChIP analyses: ChIP using anti-c-Myc antibody. ChIP-chip analyses: In all cases, hybridization data of ChIP fraction was compared with WCE (whole cell extract) fraction. Saccharomyces cerevisiae affymetrix genome tiling array (SC3456a520015F) were used. ⢠Quality control steps taken Confirmation of several loci by quantitative real time PCR. Wild type cells expressing non-tagged Rad52 were used as a negative control of DNA amplification.
2010-05-18 | E-GEOD-14761 | biostudies-arrayexpress
Project description:The Mec1 and Rad53 kinases play a central role during acute replication stress in budding yeast. They are also essential for viability in normal growth conditions, but the signal that activates the Mec1–Rad53 pathway in the absence of exogenous insults is currently unknown. Here, we show that this pathway is active at the onset of normal S phase because dNTP levels present in G1 phase are not sufficient to support processive DNA synthesis and impede DNA replication. This activation can be suppressed experimentally by increasing dNTP levels in G1 phase. Moreover, we show that unchallenged cells entering S phase in the absence of Rad53 undergo irreversible fork collapse and mitotic catastrophe. Together, these data indicate that cells use dNTP shortage to detect the onset of DNA replication and activate the Mec1–Rad53 pathway, which in turn maintains functional forks and triggers dNTP synthesis, allowing the completion of DNA replication.
2020-03-17 | GSE136602 | GEO