Schizosaccharomyces pombe Hst4 Functions in DNA Damage Response by Regulating Histone H3 K56 Acetylation

ABSTRACT The packaging of eukaryotic DNA into chromatin is likely to be crucial for the maintenance of genomic integrity. Histone acetylation and deacetylation, which alter chromatin accessibility, have been implicated in DNA damage tolerance. Here we show that Schizosaccharomyces pombe Hst4, a homolog of histone deacetylase Sir2, participates in S-phase-specific DNA damage tolerance. Hst4 was essential for the survival of cells exposed to the genotoxic agent methyl methanesulfonate (MMS) as well as for cells lacking components of the DNA damage checkpoint pathway. It was required for the deacetylation of histone H3 core domain residue lysine 56, since a strain with a point mutation of its catalytic domain was unable to deacetylate this residue in vivo. Hst4 regulated the acetylation of H3 K56 and was itself cell cycle regulated. We also show that MMS treatment resulted in increased acetylation of histone H3 lysine 56 in wild-type cells and hst4Δ mutants had constitutively elevated levels of histone H3 K56 acetylation. Interestingly, the level of expression of Hst4 decreased upon MMS treatment, suggesting that the cell regulates access to the site of DNA damage by changing the level of this protein. Furthermore, we find that the phenotypes of both K56Q and K56R mutants of histone H3 were similar to those of hst4Δ mutants, suggesting that proper regulation of histone acetylation is important for DNA integrity. We propose that Hst4 is a deacetylase involved in the restoration of chromatin structure following the S phase of cell cycle and DNA damage response.

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Dysregulation of hsa-miR-34a and hsa-miR-449a leads to overexpression of PACS-1 and loss of DNA damage response (DDR) in cervical cancer

Journal of Biological Chemistry ◽

10.1074/jbc.ra120.014048 ◽

2020 ◽

Vol 295 (50) ◽

pp. 17169-17186

Author(s):

Mysore S. Veena ◽

Santanu Raychaudhuri ◽

Saroj K. Basak ◽

Natarajan Venkatesan ◽

Parameet Kumar ◽

...

Keyword(s):

Cell Cycle ◽

Cervical Cancer ◽

Dna Damage ◽

Cell Growth ◽

Cell Lines ◽

Cancer Cell ◽

Dna Damage Response ◽

S Phase ◽

Cervical Cancer Cell ◽

Damage Response

We have observed overexpression of PACS-1, a cytosolic sorting protein in primary cervical tumors. Absence of exonic mutations and overexpression at the RNA level suggested a transcriptional and/or posttranscriptional regulation. University of California Santa Cruz genome browser analysis of PACS-1 micro RNAs (miR), revealed two 8-base target sequences at the 3′ terminus for hsa-miR-34a and hsa-miR-449a. Quantitative RT-PCR and Northern blotting studies showed reduced or loss of expression of the two microRNAs in cervical cancer cell lines and primary tumors, indicating dysregulation of these two microRNAs in cervical cancer. Loss of PACS-1 with siRNA or exogenous expression of hsa-miR-34a or hsa-miR-449a in HeLa and SiHa cervical cancer cell lines resulted in DNA damage response, S-phase cell cycle arrest, and reduction in cell growth. Furthermore, the siRNA studies showed that loss of PACS-1 expression was accompanied by increased nuclear γH2AX expression, Lys382-p53 acetylation, and genomic instability. PACS-1 re-expression through LNA-hsa-anti-miR-34a or -449a or through PACS-1 cDNA transfection led to the reversal of DNA damage response and restoration of cell growth. Release of cells post 24-h serum starvation showed PACS-1 nuclear localization at G1-S phase of the cell cycle. Our results therefore indicate that the loss of hsa-miR-34a and hsa-miR-449a expression in cervical cancer leads to overexpression of PACS-1 and suppression of DNA damage response, resulting in the development of chemo-resistant tumors.

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A Role for NIPA in DNA Damage Response.

Blood ◽

10.1182/blood.v104.11.1265.1265 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1265-1265

Author(s):

Christine von Klitzing ◽

Florian Bassermann ◽

Stephan W. Morris ◽

Christian Peschel ◽

Justus Duyster

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Damage Response ◽

Phosphorylation Site ◽

Genotoxic Stress ◽

S Phase ◽

Damage Response ◽

A Cell ◽

Cycle Dependent

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.

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DNA damage tolerance in stem cells, ageing, mutagenesis, disease and cancer therapy

Nucleic Acids Research ◽

10.1093/nar/gkz531 ◽

2019 ◽

Vol 47 (14) ◽

pp. 7163-7181 ◽

Cited By ~ 12

Author(s):

Bas Pilzecker ◽

Olimpia Alessandra Buoninfante ◽

Heinz Jacobs

Keyword(s):

Dna Damage ◽

Dna Damage Response ◽

Damage Tolerance ◽

Essential Feature ◽

Dna Lesions ◽

Template Switching ◽

Dna Damage Tolerance ◽

Response Network ◽

Damage Response ◽

Fork Stalling

AbstractThe DNA damage response network guards the stability of the genome from a plethora of exogenous and endogenous insults. An essential feature of the DNA damage response network is its capacity to tolerate DNA damage and structural impediments during DNA synthesis. This capacity, referred to as DNA damage tolerance (DDT), contributes to replication fork progression and stability in the presence of blocking structures or DNA lesions. Defective DDT can lead to a prolonged fork arrest and eventually cumulate in a fork collapse that involves the formation of DNA double strand breaks. Four principal modes of DDT have been distinguished: translesion synthesis, fork reversal, template switching and repriming. All DDT modes warrant continuation of replication through bypassing the fork stalling impediment or repriming downstream of the impediment in combination with filling of the single-stranded DNA gaps. In this way, DDT prevents secondary DNA damage and critically contributes to genome stability and cellular fitness. DDT plays a key role in mutagenesis, stem cell maintenance, ageing and the prevention of cancer. This review provides an overview of the role of DDT in these aspects.

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A role for cell-cycle-regulated histone H3 lysine 56 acetylation in the DNA damage response

Nature ◽

10.1038/nature03714 ◽

2005 ◽

Vol 436 (7048) ◽

pp. 294-298 ◽

Cited By ~ 398

Author(s):

Hiroshi Masumoto ◽

David Hawke ◽

Ryuji Kobayashi ◽

Alain Verreault

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Damage Response ◽

Histone H3 ◽

Damage Response

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Lack of CCAAT Enhancer Binding Protein Beta (C/EBPβ) in Uterine Epithelial Cells Impairs Estrogen-Induced DNA Replication, Induces DNA Damage Response Pathways, and Promotes Apoptosis

Molecular and Cellular Biology ◽

10.1128/mcb.00872-09 ◽

2010 ◽

Vol 30 (7) ◽

pp. 1607-1619 ◽

Cited By ~ 16

Author(s):

Cyril Ramathal ◽

Indrani C. Bagchi ◽

Milan K. Bagchi

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Replication ◽

Epithelial Cells ◽

Cell Cycle Arrest ◽

Dna Damage Response ◽

S Phase ◽

Uterine Epithelial Cells ◽

Cycle Arrest ◽

Damage Response

ABSTRACT Female mice lacking the transcription factor C/EBPβ are infertile and display markedly reduced estrogen (E)-induced proliferation of the uterine epithelial lining during the reproductive cycle. The present study showed that E-stimulated luminal epithelial cells of a C/EBPβ-null uterus are able to proceed through the G1 phase of the cell cycle before getting arrested in the S phase. This cell cycle arrest was accompanied by markedly reduced levels of expression of E2F3, an E2F family member, and a lack of nuclear localization of cyclin E, a critical regulator of cdk2. An increased nuclear accumulation of p27, an inhibitor of the cyclin E-cdk2 complex, was also observed for the mutant epithelium. Gene expression profiling of C/EBPβ-null uterine epithelial cells revealed that the blockade of E-induced DNA replication triggers the activation of several well-known components of the DNA damage response pathway, such as ATM, ATR, histone H2AX, checkpoint kinase 1, and tumor suppressor p53. The activation of p53 by ATM/ATR kinase led to increased levels of expression of p21, an inhibitor of G1-S-phase progression, which helps maintain cell cycle arrest. Additionally, p53-dependent mechanisms contributed to an increased apoptosis of replication-defective cells in the C/EBPβ-null epithelium. C/EBPβ, therefore, is an essential mediator of E-induced growth and survival of uterine epithelial cells of cycling mice.

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ATR- and ATM-Mediated DNA Damage Response Is Dependent on Excision Repair Assembly during G1 but Not in S Phase of Cell Cycle

PLoS ONE ◽

10.1371/journal.pone.0159344 ◽

2016 ◽

Vol 11 (7) ◽

pp. e0159344 ◽

Cited By ~ 20

Author(s):

Alo Ray ◽

Chessica Blevins ◽

Gulzar Wani ◽

Altaf A. Wani

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Damage Response ◽

Excision Repair ◽

S Phase ◽

Damage Response

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BK Polyomavirus Activates the DNA Damage Response To Prolong S Phase

Journal of Virology ◽

10.1128/jvi.00130-19 ◽

2019 ◽

Vol 93 (14) ◽

Cited By ~ 5

Author(s):

Joshua L. Justice ◽

Jason M. Needham ◽

Sunnie R. Thompson

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Dna Damage Response ◽

S Phase ◽

Genome Replication ◽

Viral Production ◽

Viral Dna ◽

Bk Polyomavirus ◽

Damage Response ◽

Infected Cells

ABSTRACT BK polyomavirus (PyV) is a major source of kidney failure in transplant recipients. The standard treatment for patients with lytic BKPyV infection is to reduce immunosuppressive therapy, which increases the risk of graft rejection. PyVs are DNA viruses that rely upon host replication proteins for viral genome replication. A hallmark of PyV infection is activation of the DNA damage response (DDR) to prevent severe host and viral DNA damage that impairs viral production by an unknown mechanism. Therefore, we sought to better understand why BKPyV activates the DDR through the ATR and ATM pathways and how this prevents DNA damage and leads to increased viral production. When ATR was inhibited in BKPyV-infected primary kidney cells, severe DNA damage occurred due to premature Cdk1 activation, which resulted in mitosis of cells that were actively replicating host DNA in S phase. Conversely, ATM was required for efficient entry into S phase and to prevent normal mitotic entry after G2 phase. The synergistic activation of these DDR kinases promoted and maintained BKPyV-mediated S phase to enhance viral production. In contrast to BKPyV infection, DDR inhibition did not disrupt cell cycle control in uninfected cells. This suggests that DDR inhibitors may be used to specifically target BKPyV-infected cells. IMPORTANCE BK polyomavirus (BKPyV) is an emerging pathogen that reactivates in immunosuppressed organ transplant patients. We wanted to understand why BKPyV-induced activation of the DNA damage response (DDR) enhances viral titers and prevents host DNA damage. Here, we show that the virus activates the DNA damage response in order to keep the infected cells in S phase to replicate the viral DNA. The source of DNA damage was due to actively replicating cells with uncondensed chromosomes entering directly into mitosis when the DDR was inhibited in BKPyV-infected cells. This study clarifies the previously enigmatic role of the DDR during BKPyV infection by demonstrating that the virus activates the DDR to maintain the cells in S phase in order to promote viral replication and that disruption of this cell cycle arrest can lead to catastrophic DNA damage for the host.

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Tof1p Regulates DNA Damage Responses During S Phase in Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/157.2.567 ◽

2001 ◽

Vol 157 (2) ◽

pp. 567-577 ◽

Cited By ~ 2

Author(s):

Eric J Foss

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Cycle ◽

Dna Damage ◽

Dna Damage Response ◽

Double Mutant ◽

S Phase ◽

Damage Response ◽

Dna Damage Responses ◽

Dna Damage Response Pathway

Abstract A tof1 mutant was recovered in a screen aimed at identifying genes involved specifically in the S phase branch of the MEC1-dependent DNA damage response pathway. The screen was based on the observation that mutants missing this branch are particularly dependent on the cell cycle-wide branch and, therefore, on RAD9, for surviving DNA damage. tof1 and rad9 conferred synergistic sensitivity to MMS, UV, and HU, and the double mutant was incapable of slowing S phase in response to MMS, inducing RNR3 transcription in response to UV, and phosphorylating Rad53p in response to HU. TOF1's contribution to DNA damage response appeared to be restricted to S phase, since TOF1 did not contribute to UV-induced transcription during G1 or to the cdc13-1-induced block to anaphase in G2/M. I suggest a model in which Tof1p functions to link Mec1p with Rad53p.

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Identification of New Players in Cell Division, DNA Damage Response, and Morphogenesis Through Construction of Schizosaccharomyces pombe Deletion Strains

G3 Genes|Genome|Genetics ◽

10.1534/g3.114.015701 ◽

2015 ◽

Vol 5 (3) ◽

pp. 361-370 ◽

Cited By ~ 10

Author(s):

Jun-Song Chen ◽

Janel R Beckley ◽

Nathan A McDonald ◽

Liping Ren ◽

MariaSanta Mangione ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Schizosaccharomyces Pombe ◽

Dna Damage Response ◽

Gene Deletion ◽

Biological Processes ◽

Gene Deletions ◽

New Genes ◽

Damage Response ◽

Nonessential Gene

Abstract Many fundamental biological processes are studied using the fission yeast, Schizosaccharomyces pombe. Here we report the construction of a set of 281 haploid gene deletion strains covering many previously uncharacterized genes. This collection of strains was tested for growth under a variety of different stress conditions. We identified new genes involved in DNA metabolism, completion of the cell cycle, and morphogenesis. This subset of nonessential gene deletions will add to the toolkits available for the study of biological processes in S. pombe.

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