Abf1 Is an Essential Protein That Participates in Cell Cycle Progression and Subtelomeric Silencing in Candida glabrata

Accurate DNA replication and segregation is key to reproduction and cell viability in all organisms. Autonomously replicating sequence-binding factor 1 (Abf1) is a multifunctional protein that has essential roles in replication, transcription, and regional silencing in the model yeast Saccharomyces cerevisiae. In the opportunistic pathogenic fungus Candida glabrata, which is closely related to S. cerevisiae, these processes are important for survival within the host, for example, the regulation of transcription of virulence-related genes like those involved in adherence. Here, we describe that CgABF1 is an essential gene required for cell viability and silencing near the telomeres, where many adhesin-encoding genes reside. CgAbf1 mediated subtelomeric silencing depends on the 43 C-terminal amino acids. We also found that abnormal expression, depletion, or overexpression of Abf1, results in defects in nuclear morphology, nuclear segregation, and transit through the cell cycle. In the absence of ABF1, cells are arrested in G2 but start cycling again after 9 h, coinciding with the loss of cell viability and the appearance of cells with higher DNA content. Overexpression of CgABF1 causes defects in nuclear segregation and cell cycle progression. We suggest that these effects could be due to the deregulation of DNA replication.

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A Survey of Essential Gene Function in the Yeast Cell Division Cycle

Molecular Biology of the Cell ◽

10.1091/mbc.e06-04-0368 ◽

2006 ◽

Vol 17 (11) ◽

pp. 4736-4747 ◽

Cited By ~ 67

Author(s):

Lisa Yu ◽

Lourdes Peña Castillo ◽

Sanie Mnaimneh ◽

Timothy R. Hughes ◽

Grant W. Brown

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Yeast Cell ◽

Dna Content ◽

Cell Cycle Progression ◽

Essential Gene ◽

Nucleotide Metabolism ◽

Cycle Progression ◽

New Genes ◽

Yeast Genes

Mutations impacting specific stages of cell growth and division have provided a foundation for dissecting mechanisms that underlie cell cycle progression. We have undertaken an objective examination of the yeast cell cycle through flow cytometric analysis of DNA content in TetO7promoter mutant strains representing 75% of all essential yeast genes. More than 65% of the strains displayed specific alterations in DNA content, suggesting that reduced function of an essential gene in most cases impairs progression through a specific stage of the cell cycle. Because of the large number of essential genes required for protein biosynthesis, G1 accumulation was the most common phenotype observed in our analysis. In contrast, relatively few mutants displayed S-phase delay, and most of these were defective in genes required for DNA replication or nucleotide metabolism. G2 accumulation appeared to arise from a variety of defects. In addition to providing a global view of the diversity of essential cellular processes that influence cell cycle progression, these data also provided predictions regarding the functions of individual genes: we identified four new genes involved in protein trafficking (NUS1, PHS1, PGA2, PGA3), and we found that CSE1 and SMC4 are important for DNA replication.

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Regulation of Cell Division in Bacteria by Monitoring Genome Integrity and DNA Replication Status

Journal of Bacteriology ◽

10.1128/jb.00408-19 ◽

2019 ◽

Vol 202 (2) ◽

Cited By ~ 5

Author(s):

Peter E. Burby ◽

Lyle A. Simmons

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Division ◽

Dna Replication ◽

Cell Cycle Progression ◽

Genome Instability ◽

Sos Response ◽

Bacterial Cells ◽

Cycle Progression ◽

Content Type

ABSTRACT All organisms regulate cell cycle progression by coordinating cell division with DNA replication status. In eukaryotes, DNA damage or problems with replication fork progression induce the DNA damage response (DDR), causing cyclin-dependent kinases to remain active, preventing further cell cycle progression until replication and repair are complete. In bacteria, cell division is coordinated with chromosome segregation, preventing cell division ring formation over the nucleoid in a process termed nucleoid occlusion. In addition to nucleoid occlusion, bacteria induce the SOS response after replication forks encounter DNA damage or impediments that slow or block their progression. During SOS induction, Escherichia coli expresses a cytoplasmic protein, SulA, that inhibits cell division by directly binding FtsZ. After the SOS response is turned off, SulA is degraded by Lon protease, allowing for cell division to resume. Recently, it has become clear that SulA is restricted to bacteria closely related to E. coli and that most bacteria enforce the DNA damage checkpoint by expressing a small integral membrane protein. Resumption of cell division is then mediated by membrane-bound proteases that cleave the cell division inhibitor. Further, many bacterial cells have mechanisms to inhibit cell division that are regulated independently from the canonical LexA-mediated SOS response. In this review, we discuss several pathways used by bacteria to prevent cell division from occurring when genome instability is detected or before the chromosome has been fully replicated and segregated.

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Cell cycle progression: computer simulation of uncoupled subcycles of DNA replication and cell growth

Journal of Theoretical Biology ◽

10.1006/jtbi.1995.0130 ◽

1995 ◽

Vol 175 (2) ◽

pp. 177-189 ◽

Cited By ~ 9

Author(s):

Roland Sennerstam ◽

Jan-Olof Strömberg

Keyword(s):

Cell Cycle ◽

Computer Simulation ◽

Dna Replication ◽

Cell Growth ◽

Cell Cycle Progression ◽

Cycle Progression

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Deregulated expression of the RanBP1 gene alters cell cycle progression in murine fibroblasts

Journal of Cell Science ◽

10.1242/jcs.110.19.2345 ◽

1997 ◽

Vol 110 (19) ◽

pp. 2345-2357 ◽

Cited By ~ 1

Author(s):

A. Battistoni ◽

G. Guarguaglini ◽

F. Degrassi ◽

C. Pittoggi ◽

A. Palena ◽

...

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Cell Cycle Progression ◽

Protein Import ◽

Proliferating Cells ◽

Cycle Progression ◽

Ran Gtpase ◽

Genes Encoding ◽

Active Transcription ◽

Gtpase Cycle

RanBP1 is a molecular partner of the Ran GTPase, which is implicated in the control of several processes, including DNA replication, mitotic entry and exit, cell cycle progression, nuclear structure, protein import and RNA export. While most genes encoding Ran-interacting partners are constitutively active, transcription of the RanBP1 mRNA is repressed in non proliferating cells, is activated at the G1/S transition in cycling cells and peaks during S phase. We report here that forced expression of the RanBP1 gene disrupts the orderly execution of the cell division cycle at several stages, causing inhibition of DNA replication, defective mitotic exit and failure of chromatin decondensation during the telophase-to-interphase transition in cells that achieve nuclear duplication and chromosome segregation. These results suggest that deregulated RanBP1 activity interferes with the Ran GTPase cycle and prevents the functioning of the Ran signalling system during the cell cycle.

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Microarray gene expression profiling in colorectal (HCT116) and hepatocellular (HepG2) carcinoma cell lines treated withMelicope ptelefolialeaf extract reveals transcriptome profiles exhibiting anticancer activity

PeerJ ◽

10.7717/peerj.5203 ◽

2018 ◽

Vol 6 ◽

pp. e5203 ◽

Cited By ~ 6

Author(s):

Mohammad Faujul Kabir ◽

Johari Mohd Ali ◽

Onn Haji Hashim

Keyword(s):

Gene Expression ◽

Cell Cycle ◽

Dna Replication ◽

Cell Lines ◽

Microarray Data ◽

Expression Profiling ◽

Cell Cycle Progression ◽

Anticancer Activities ◽

Microarray Gene Expression ◽

Cycle Progression

BackgroundWe have previously reported anticancer activities ofMelicope ptelefolia(MP) leaf extracts on four different cancer cell lines. However, the underlying mechanisms of actions have yet to be deciphered. In the present study, the anticancer activity of MP hexane extract (MP-HX) on colorectal (HCT116) and hepatocellular carcinoma (HepG2) cell lines was characterized through microarray gene expression profiling.MethodsHCT116 and HepG2 cells were treated with MP-HX for 24 hr. Total RNA was extracted from the cells and used for transcriptome profiling using Applied Biosystem GeneChip™ Human Gene 2.0 ST Array. Gene expression data was analysed using an Applied Biosystems Expression Console and Transcriptome Analysis Console software. Pathway enrichment analyses was performed using Ingenuity Pathway Analysis (IPA) software. The microarray data was validated by profiling the expression of 17 genes through quantitative reverse transcription PCR (RT-qPCR).ResultsMP-HX induced differential expression of 1,290 and 1,325 genes in HCT116 and HepG2 cells, respectively (microarray data fold change, MA_FC ≥ ±2.0). The direction of gene expression change for the 17 genes assayed through RT-qPCR agree with the microarray data. In both cell lines, MP-HX modulated the expression of many genes in directions that support antiproliferative activity. IPA software analyses revealed MP-HX modulated canonical pathways, networks and biological processes that are associated with cell cycle, DNA replication, cellular growth and cell proliferation. In both cell lines, upregulation of genes which promote apoptosis, cell cycle arrest and growth inhibition were observed, while genes that are typically overexpressed in diverse human cancers or those that promoted cell cycle progression, DNA replication and cellular proliferation were downregulated. Some of the genes upregulated by MP-HX include pro-apoptotic genes (DDIT3, BBC3, JUN), cell cycle arresting (CDKN1A, CDKN2B), growth arrest/repair (TP53, GADD45A) and metastasis suppression (NDRG1). MP-HX downregulated the expression of genes that could promote anti-apoptotic effect, cell cycle progression, tumor development and progression, which include BIRC5, CCNA2, CCNB1, CCNB2, CCNE2, CDK1/2/6, GINS2, HELLS, MCM2/10 PLK1, RRM2 and SKP2. It is interesting to note that all six top-ranked genes proposed to be cancer-associated (PLK1, MCM2, MCM3, MCM7, MCM10 and SKP2) were downregulated by MP-HX in both cell lines.DiscussionThe present study showed that the anticancer activities of MP-HX are exerted through its actions on genes regulating apoptosis, cell proliferation, DNA replication and cell cycle progression. These findings further project the potential use of MP as a nutraceutical agent for cancer therapeutics.

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GINS2 affects cell viability, cell apoptosis, and cell cycle progression of pancreatic cancer cells via MAPK/ERK pathway

Journal of Cancer ◽

10.7150/jca.38386 ◽

2020 ◽

Vol 11 (16) ◽

pp. 4662-4670

Author(s):

Miao Zhang ◽

Saifei He ◽

Xing Ma ◽

Ying Ye ◽

Guoyu Wang ◽

...

Keyword(s):

Cell Cycle ◽

Pancreatic Cancer ◽

Cell Viability ◽

Cancer Cells ◽

Cell Apoptosis ◽

Cell Cycle Progression ◽

Erk Pathway ◽

Cycle Progression ◽

Pancreatic Cancer Cells

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Evidence for a dual role for TC4 protein in regulating nuclear structure and cell cycle progression.

The Journal of Cell Biology ◽

10.1083/jcb.125.4.705 ◽

1994 ◽

Vol 125 (4) ◽

pp. 705-719 ◽

Cited By ~ 77

Author(s):

S Kornbluth ◽

M Dasso ◽

J Newport

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Nuclear Structure ◽

Cell Cycle Progression ◽

Cycle Progression ◽

Nuclear Assembly ◽

Egg Extracts ◽

A Cell ◽

Xenopus Egg Extracts

TC4, a ras-like G protein, has been implicated in the feedback pathway linking the onset of mitosis to the completion of DNA replication. In this report we find distinct roles for TC4 in both nuclear assembly and cell cycle progression. Mutant and wild-type forms of TC4 were added to Xenopus egg extracts capable of assembling nuclei around chromatin templates in vitro. We found that a mutant TC4 protein defective in GTP binding (GDP-bound form) suppressed nuclear growth and prevented DNA replication. Nuclear transport under these conditions approximated normal levels. In a separate set of experiments using a cell-free extract of Xenopus eggs that cycles between S and M phases, the GDP-bound form of TC4 had dramatic effects, blocking entry into mitosis even in the complete absence of nuclei. The effect of this mutant TC4 protein on cell cycle progression is mediated by phosphorylation of p34cdc2 on tyrosine and threonine residues, negatively regulating cdc2 kinase activity. Therefore, we provide direct biochemical evidence for a role of TC4 in both maintaining nuclear structure and in the signaling pathways that regulate entry into mitosis.

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Identification of DHX9 as a cell cycle regulated nucleolar recruitment factor for CIZ1

Scientific Reports ◽

10.1038/s41598-020-75160-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Urvi Thacker ◽

Tekle Pauzaite ◽

James Tollitt ◽

Maria Twardowska ◽

Charlotte Harrison ◽

...

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Cell Cycle Progression ◽

Zinc Finger Protein ◽

S Phase ◽

Cycle Progression ◽

Inactive X Chromosome ◽

Functional Characterisation ◽

Interaction Partners

Abstract CIP1-interacting zinc finger protein 1 (CIZ1) is a nuclear matrix associated protein that facilitates a number of nuclear functions including initiation of DNA replication, epigenetic maintenance and associates with the inactive X-chromosome. Here, to gain more insight into the protein networks that underpin this diverse functionality, molecular panning and mass spectrometry are used to identify protein interaction partners of CIZ1, and CIZ1 replication domain (CIZ1-RD). STRING analysis of CIZ1 interaction partners identified 2 functional clusters: ribosomal subunits and nucleolar proteins including the DEAD box helicases, DHX9, DDX5 and DDX17. DHX9 shares common functions with CIZ1, including interaction with XIST long-non-coding RNA, epigenetic maintenance and regulation of DNA replication. Functional characterisation of the CIZ1-DHX9 complex showed that CIZ1-DHX9 interact in vitro and dynamically colocalise within the nucleolus from early to mid S-phase. CIZ1-DHX9 nucleolar colocalisation is dependent upon RNA polymerase I activity and is abolished by depletion of DHX9. In addition, depletion of DHX9 reduced cell cycle progression from G1 to S-phase in mouse fibroblasts. The data suggest that DHX9-CIZ1 are required for efficient cell cycle progression at the G1/S transition and that nucleolar recruitment is integral to their mechanism of action.

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