The Gene Expression and Enzyme Activity of Plant 3-Deoxy-D-Manno-2-Octulosonic Acid-8-Phosphate Synthase Are Preferentially Associated with Cell Division in a Cell Cycle-Dependent Manner

The segregation of the genome into accessible euchromatin and histone H3K9-methylated heterochromatin helps silence repetitive elements and tissue-specific genes. In Caenorhabditis elegans, MET-2, the homologue of mammalian SETDB1, catalyzes H3K9me1 and me2, yet like SETDB1, its regulation is enigmatic. Contrary to the cytosolic enrichment of overexpressed MET-2, we show that endogenous MET-2 is nuclear throughout development, forming perinuclear foci in a cell cycle–dependent manner. Mass spectrometry identified two cofactors that bind MET-2: LIN-65, a highly unstructured protein, and ARLE-14, a conserved GTPase effector. All three factors colocalize in heterochromatic foci. Ablation of lin-65, but not arle-14, mislocalizes and destabilizes MET-2, resulting in decreased H3K9 dimethylation, dispersion of heterochromatic foci, and derepression of MET-2 targets. Mutation of met-2 or lin-65 also disrupts the perinuclear anchoring of genomic heterochromatin. Loss of LIN-65, like that of MET-2, compromises temperature stress resistance and germline integrity, which are both linked to promiscuous repeat transcription and gene expression.

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NSun2 Promotes Cell Growth via Elevating Cyclin-Dependent Kinase 1 Translation

Molecular and Cellular Biology ◽

10.1128/mcb.00742-15 ◽

2015 ◽

Vol 35 (23) ◽

pp. 4043-4052 ◽

Cited By ~ 38

Author(s):

Junyue Xing ◽

Jie Yi ◽

Xiaoyu Cai ◽

Hao Tang ◽

Zhenyun Liu ◽

...

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Cell Division Cycle ◽

Mrna Levels ◽

Dependent Manner ◽

Cyclin Dependent Kinase ◽

A Cell ◽

Cycle Dependent ◽

Insight Into

The tRNA methytransferase NSun2 promotes cell proliferation, but the molecular mechanism has not been elucidated. Here, we report that NSun2 regulates cyclin-dependent kinase 1 (CDK1) expression in a cell cycle-dependent manner. Knockdown of NSun2 decreased the CDK1 protein level, while overexpression of NSun2 elevated it without alteringCDK1mRNA levels. Further studies revealed that NSun2 methylatedCDK1mRNAin vitroand in cells and that methylation by NSun2 enhanced CDK1 translation. Importantly, NSun2-mediated regulation of CDK1 expression had an impact on the cell division cycle. These results provide new insight into the regulation of CDK1 during the cell division cycle.

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Truncated APC regulates the transcriptional activity of β-catenin in a cell cycle dependent manner

Human Molecular Genetics ◽

10.1093/hmg/ddl464 ◽

2006 ◽

Vol 16 (2) ◽

pp. 199-209 ◽

Cited By ~ 38

Author(s):

Jean Schneikert ◽

Annette Grohmann ◽

Jürgen Behrens

Keyword(s):

Cell Cycle ◽

Transcriptional Activity ◽

Dependent Manner ◽

A Cell ◽

Cycle Dependent

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Effects of cell-cycle-dependent expression on random fluctuations in protein levels

Royal Society Open Science ◽

10.1098/rsos.160578 ◽

2016 ◽

Vol 3 (12) ◽

pp. 160578 ◽

Cited By ~ 20

Author(s):

Mohammad Soltani ◽

Abhyudai Singh

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Protein Levels ◽

Stochastic Component ◽

Stochastic Expression ◽

A Cell ◽

Intrinsic Stochasticity ◽

Cycle Dependent ◽

Random Fluctuations ◽

Cell To Cell Variability

Expression of many genes varies as a cell transitions through different cell-cycle stages. How coupling between stochastic expression and cell cycle impacts cell-to-cell variability (noise) in the level of protein is not well understood. We analyse a model where a stable protein is synthesized in random bursts, and the frequency with which bursts occur varies within the cell cycle. Formulae quantifying the extent of fluctuations in the protein copy number are derived and decomposed into components arising from the cell cycle and stochastic processes. The latter stochastic component represents contributions from bursty expression and errors incurred during partitioning of molecules between daughter cells. These formulae reveal an interesting trade-off: cell-cycle dependencies that amplify the noise contribution from bursty expression also attenuate the contribution from partitioning errors. We investigate the existence of optimum strategies for coupling expression to the cell cycle that minimize the stochastic component. Intriguingly, results show that a zero production rate throughout the cell cycle, with expression only occurring just before cell division, minimizes noise from bursty expression for a fixed mean protein level. By contrast, the optimal strategy in the case of partitioning errors is to make the protein just after cell division. We provide examples of regulatory proteins that are expressed only towards the end of the cell cycle, and argue that such strategies enhance robustness of cell-cycle decisions to the intrinsic stochasticity of gene expression.

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Ser68 phosphoregulation is essential for CENP-A deposition, centromere function and viability in mice

10.1101/2021.11.23.469796 ◽

2021 ◽

Author(s):

Yuting Liu ◽

Kehui Wang ◽

Li Huang ◽

Jicheng Zhao ◽

Xinpeng Chen ◽

...

Keyword(s):

Cell Cycle ◽

Cell Viability ◽

Histone H3 ◽

Dependent Manner ◽

Centromere Function ◽

Histone H3 Variant ◽

A Cell ◽

Cycle Dependent ◽

Spatiotemporal Control

Centromere identity is defined by nucleosomes containing CENP-A, a histone H3 variant. The deposition of CENP-A at centromeres is tightly regulated in a cell-cycle-dependent manner. We previously reported that the spatiotemporal control of centromeric CENP-A incorporation is mediated by the phosphorylation of CENP-A Ser68. However, a recent report argued that Ser68 phosphoregulation is dispensable for accurate CENP-A loading. Here, we report that the substitution of Ser68 of endogenous CENP-A with either Gln68 or Glu68 severely impairs CENP-A deposition and cell viability. We also find that mice harboring the corresponding mutations are lethal. Together, these results indicate that the dynamic phosphorylation of Ser68 ensures cell-cycle-dependent CENP-A deposition and cell viability.

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Gcn5-mediated acetylation at MBF-regulated promoters induces the G1/S transcriptional wave

Nucleic Acids Research ◽

10.1093/nar/gkz561 ◽

2019 ◽

Vol 47 (16) ◽

pp. 8439-8451 ◽

Cited By ~ 1

Author(s):

Alberto González-Medina ◽

Elena Hidalgo ◽

José Ayté

Keyword(s):

Cell Cycle ◽

Molecular Mechanisms ◽

Histone H3 ◽

Dependent Manner ◽

Saga Complex ◽

Lysine Residues ◽

Physical Barriers ◽

A Cell ◽

Cycle Dependent ◽

Regulated Promoters

Abstract In fission yeast, MBF-dependent transcription is inactivated at the end of S phase through a negative feedback loop that involves the co-repressors, Yox1 and Nrm1. Although this repression system is well known, the molecular mechanisms involved in MBF activation remain largely unknown. Compacted chromatin constitutes a barrier to activators accessing promoters. Here, we show that chromatin regulation plays a key role in activating MBF-dependent transcription. Gcn5, a part of the SAGA complex, binds to MBF-regulated promoters through the MBF co-activator Rep2 in a cell cycle-dependent manner and in a reverse correlation to the binding of the MBF co-repressors, Nrm1 or Yox1. We propose that the co-repressors function as physical barriers to SAGA recruitment onto MBF promoters. We also show that Gcn5 acetylates specific lysine residues on histone H3 in a cell cycle-regulated manner. Furthermore, either in a gcn5 mutant or in a strain in which histone H3 is kept in an unacetylated form, MBF-dependent transcription is downregulated. In summary, Gcn5 is required for the full activation and correct timing of MBF-regulated gene transcription.

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