scholarly journals Coordination of Cell Cycle Progression and Mitotic Spindle Assembly Involves Histone H3 Lysine 4 Methylation by Set1/COMPASS

Genetics ◽  
2016 ◽  
Vol 205 (1) ◽  
pp. 185-199 ◽  
Author(s):  
Traude H. Beilharz ◽  
Paul F. Harrison ◽  
Douglas Maya Miles ◽  
Michael Ming See ◽  
Uyen Minh Merry Le ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Mitotic Spindle ◽  
Cell Cycle Progression ◽  
Histone H3 ◽  
Spindle Assembly ◽  
Cycle Progression ◽  
Mitotic Spindle Assembly

The role of gamma-tubulin in mitotic spindle formation and cell cycle progression in Aspergillus nidulans

1997 ◽  
Vol 110 (5) ◽  
pp. 623-633 ◽  
Author(s):  
M.A. Martin ◽  
S.A. Osmani ◽  
B.R. Oakley
Keyword(s):  
Cell Cycle ◽  
Mitotic Spindle ◽  
Cell Cycle Progression ◽  
Spindle Pole ◽  
Microtubule Assembly ◽  
Cytoplasmic Microtubule ◽  
Cycle Progression ◽  
Spindle Microtubules ◽  
Gamma Tubulin

gamma-Tubulin has been hypothesized to be essential for the nucleation of the assembly of mitotic spindle microtubules, but some recent results suggest that this may not be the case. To clarify the role of gamma-tubulin in microtubule assembly and cell-cycle progression, we have developed a novel variation of the gene disruption/heterokaryon rescue technique of Aspergillus nidulans. We have used temperature-sensitive cell-cycle mutations to synchronize germlings carrying a gamma-tubulin disruption and observe the phenotypes caused by the disruption in the first cell cycle after germination. Our results indicate that gamma-tubulin is absolutely required for the assembly of mitotic spindle microtubules, a finding that supports the hypothesis that gamma-tubulin is involved in spindle microtubule nucleation. In the absence of functional gamma-tubulin, nuclei are blocked with condensed chromosomes for about the length of one cell cycle before chromatin decondenses without nuclear division. Our results indicate that gamma-tubulin is not essential for progression from G1 to G2, for entry into mitosis nor for spindle pole body replication. It is also not required for reactivity of spindle pole bodies with the MPM-2 antibody which recognizes a phosphoepitope important to mitotic spindle formation. Finally, it does not appear to be absolutely required for cytoplasmic microtubule assembly but may play a role in the formation of normal cytoplasmic microtubule arrays.

Characterization of HDACI OSU42 as a Novel Histone Deacetylase Inhibitor in AML Cell Lines.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1988-1988
Author(s):  
Jin Sun ◽  
Shujun Liu ◽  
Jianhua Yu ◽  
Min Wei ◽  
Charlene Mao ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Gene Silencing ◽  
Cell Cycle Progression ◽  
Chromatin Condensation ◽  
Regulation Of Gene Expression ◽  
Histone H3 ◽  
Malignant Cells ◽  
Cycle Progression ◽  
Nb4 Cells ◽  
Histone Hypoacetylation

Abstract Histone acetylation plays a key role in the regulation of gene expression. Histone hyperacetylation is associated with chromatin opening and gene transcription, while histone hypoacetylation is associated with chromatin condensation and gene silencing. Abnormal histone hypoacetylation mediated by aberrant activity of histone deacetylases (HDACs) has been found to be associated with silencing of tumor suppressor and growth inhibitory genes in malignant cells. HDAC inhibitors (HDACIs) can relieve HDAC-mediated gene silencing and thereby induce normal patterns of cell cycle, differentiation and apoptosis in malignant cells. HDACI OSU 42 is a novel hydroxamate tethered phenylbutyrate derivative that was designed and synthesized at our institution, and exhibited IC50s at submicromolar level, compared with millimolar level for other members of this classes of HDACIs such as valproic acid (VPA). We characterized the activity of this compound in acute myeloid leukemia (AML) cells. It is known that the fusion proteins AML1/ETO and PML / RAR alpha that characterized t(8;21) and t(15;17) AML silence target genes through recruitment of HDACs to their promoter regions. Therefore we utilized AML1/ETO-positive Kasumi-1 and PML/RARA-positive NB4 cells to test the activity of HDACI OSU 42 and used THP-1 cells, characterized by AF9/MLL fusion gene, as a control. We hypothesized that by virtue of the fusion genes, Kasumi-1 and NB4 are more susceptible to HDACI treatment. IC50s for proliferation inhibition in Kasumi-1 cells treated with HDACI OSU42 were 71.8±14.3nM for 24hr and 31.3± 0.4nM for 48hr, significantly lower than VPA (2.0mM for 24hr, 0.9mM for 48hr). The IC50s for NB4 were 237.7±6.5nM for 24hr and 119±6.4nM for 48hr. As a contrast, IC50 for THP-1 was 507.3±68.3nM for 48hr. HDACI OSU42 inhibited 80% of total HDAC activity at 125nM in both Kasumi-1 and NB4; 30nM HDACI OSU42 induced hyperacetylation of histone H3 and H4. Apoptosis analysis showed that nearly 60% more of Kasumi-1 and NB4 underwent apoptosis after treated with 1μM of HDACI OSU42 for 24hr, compared with their untreated control. On the other hand, the same treatment only induced 15% more of THP-1 undergoing apoptosis. Apoptotic effect of HDACI OSU42 was mediated by activation of caspase 9 and caspase 3. Cell cycle analysis demonstrated that treatment of Kasumi-1 and NB4 with 150nM of HDACI OSU 42 inhibited cell cycle progression and arrested 20% to 30% more cells at S phase or G2/M phase, whereas this treatment had not effect on cell cycle progression of THP-1. This was consistent with the up-regulated expression of p21 at both transcription level and protein level. Q-PCR data suggested that Kasumi-1 and NB4 treated with HDACI OSU42 expressed ~10 folds of p21 higher than untreated cells. Chromatin immunoprecipitation assay revealed 10 to 50 folds increase in acetylation level of histone H3 and H4 associated with p21 promoter. Kasumi-1 and NB4 cells also show differentiation ability (increase in CD14 and CD 13 expression by flow cytometry) when treated with 30nM of HDACI OSU42, whereas THP-1 remained undifferentiated. These results support the activity of HDACI OSU42 as a new potent HDACI in AML.

scholarly journals Budding Yeast Bub2 Is Localized at Spindle Pole Bodies and Activates the Mitotic Checkpoint via a Different Pathway from Mad2

1999 ◽  
Vol 145 (5) ◽  
pp. 979-991 ◽  
Author(s):  
Roberta Fraschini ◽  
Elisa Formenti ◽  
Giovanna Lucchini ◽  
Simonetta Piatti
Keyword(s):  
Cell Cycle ◽  
Mitotic Spindle ◽  
Cell Cycle Progression ◽  
Budding Yeast ◽  
Spindle Pole Body ◽  
Mitotic Checkpoint ◽  
Spindle Pole ◽  
Cycle Progression ◽  
Spindle Pole Bodies

The mitotic checkpoint blocks cell cycle progression before anaphase in case of mistakes in the alignment of chromosomes on the mitotic spindle. In budding yeast, the Mad1, 2, 3, and Bub1, 2, 3 proteins mediate this arrest. Vertebrate homologues of Mad1, 2, 3, and Bub1, 3 bind to unattached kinetochores and prevent progression through mitosis by inhibiting Cdc20/APC-mediated proteolysis of anaphase inhibitors, like Pds1 and B-type cyclins. We investigated the role of Bub2 in budding yeast mitotic checkpoint. The following observations indicate that Bub2 and Mad1, 2 probably activate the checkpoint via different pathways: (a) unlike the other Mad and Bub proteins, Bub2 localizes at the spindle pole body (SPB) throughout the cell cycle; (b) the effect of concomitant lack of Mad1 or Mad2 and Bub2 is additive, since nocodazole-treated mad1 bub2 and mad2 bub2 double mutants rereplicate DNA more rapidly and efficiently than either single mutant; (c) cell cycle progression of bub2 cells in the presence of nocodazole requires the Cdc26 APC subunit, which, conversely, is not required for mad2 cells in the same conditions. Altogether, our data suggest that activation of the mitotic checkpoint blocks progression through mitosis by independent and partially redundant mechanisms.

scholarly journals Alpha-Tubulin Acetylation in Trypanosoma cruzi: A Dynamic Instability of Microtubules Is Required for Replication and Cell Cycle Progression

2021 ◽  
Vol 11 ◽  
Author(s):  
Victoria Lucia Alonso ◽  
Mara Emilia Carloni ◽  
Camila Silva Gonçalves ◽  
Gonzalo Martinez Peralta ◽  
Maria Eugenia Chesta ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Trypanosoma Cruzi ◽  
Basal Body ◽  
Mitotic Spindle ◽  
Cell Cycle Progression ◽  
Dynamic Instability ◽  
Cycle Progression ◽  
Alpha Tubulin ◽  
Over Expression ◽  
Tubulin Acetylation

Trypanosomatids have a cytoskeleton arrangement that is simpler than what is found in most eukaryotic cells. However, it is precisely organized and constituted by stable microtubules. Such microtubules compose the mitotic spindle during mitosis, the basal body, the flagellar axoneme and the subpellicular microtubules, which are connected to each other and also to the plasma membrane forming a helical arrangement along the central axis of the parasite cell body. Subpellicular, mitotic and axonemal microtubules are extensively acetylated inTrypanosoma cruzi. Acetylation on lysine (K) 40 of α-tubulin is conserved from lower eukaryotes to mammals and is associated with microtubule stability. It is also known that K40 acetylation occurs significantly on flagella, centrioles, cilia, basal body and the mitotic spindle in eukaryotes. Several tubulin posttranslational modifications, including acetylation of K40, have been cataloged in trypanosomatids, but the functional importance of these modifications for microtubule dynamics and parasite biology remains largely undefined. The primary tubulin acetyltransferase was recently identified in several eukaryotes as Mec-17/ATAT, a Gcn5-related N-acetyltransferase. Here, we report thatT. cruziATAT acetylates α-tubulinin vivoand is capable of auto-acetylation.TcATAT is located in the cytoskeleton and flagella of epimastigotes and colocalizes with acetylated α-tubulin in these structures. We have expressedTcATAT with an HA tag using the inducible vector pTcINDEX-GW inT. cruzi. Over-expression ofTcATAT causes increased levels of the alpha tubulin acetylated species, induces morphological and ultrastructural defects, especially in the mitochondrion, and causes a halt in the cell cycle progression of epimastigotes, which is related to an impairment of the kinetoplast division. Finally, as a result ofTcATAT over-expression we observed that parasites became more resistant to microtubule depolymerizing drugs. These results support the idea that α-tubulin acetylation levels are finely regulated for the normal progression ofT. cruzicell cycle.

scholarly journals Association of human ubiquitin-conjugating enzyme CDC34 with the mitotic spindle in anaphase

2000 ◽  
Vol 113 (10) ◽  
pp. 1687-1694 ◽  
Author(s):  
F. Reymond ◽  
C. Wirbelauer ◽  
W. Krek
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Mitotic Spindle ◽  
Mammalian Cells ◽  
Cell Cycle Progression ◽  
Intracellular Localization ◽  
Cycle Progression ◽  
Ubiquitin Conjugating Enzyme ◽  
Regulation Of Cell Cycle ◽  
Conjugating Enzyme

Present in organisms ranging from yeast to man, homologues of the Saccharomyces cerevisiae ubiquitin-conjugating enzyme CDC34 have been shown to play important roles in the regulation of cell cycle progression and checkpoint function. Here we analyze the expression and intracellular localization of endogenous CDC34 during mammalian cell cycle progression. We find that CDC34 protein is constitutively expressed during all stages of the cell cycle. Immunofluorescence experiments reveal that during interphase, endogenous CDC34 is localized to distinct speckles in both the nucleus and the cytoplasm. The presence of CDC34 in these compartments has also been established by biochemical fractionation experiments. Interestingly, nuclear localization depends on the presence of specific carboxy-terminal CDC34 sequences that have previously been shown to be required for CDC34's cell cycle function in Saccharomyces cerevisiae. Finally, we find that in anaphase and not during early stages of mitosis, CDC34 colocalizes with (beta)-tubulin at the mitotic spindle, implying that it may contribute to spindle function at later stages of mitosis. Taken together, these results support a model in which CDC34 ubiquitin-conjugating enzyme functions in the regulation of nuclear and cytoplasmic activities as well as in the process of chromosome segregation at the onset of anaphase in mammalian cells.

scholarly journals Excess histone H3 is a Chk1 inhibitor that controls embryonic cell cycle progression

2020 ◽  
Author(s):  
Yuki Shindo ◽  
Amanda A. Amodeo
Keyword(s):  
Cell Cycle ◽  
Cell Fate ◽  
Cell Cycle Progression ◽  
Histone H3 ◽  
Embryonic Cell ◽  
Cycle Progression ◽  
Cell Cycles ◽  
Embryonic Cell Cycle

AbstractThe early embryos of many species undergo a switch from rapid, reductive cleavage divisions to slower, cell fate-specific division patterns at the Mid-Blastula Transition (MBT). The maternally loaded histone pool is used to measure the increasing ratio of nuclei to cytoplasm (N/C ratio) to control MBT onset, but the molecular mechanism of how histones regulate the cell cycle has remained elusive. Here, we show that excess histone H3 inhibits the DNA damage checkpoint kinase Chk1 to promote cell cycle progression in the Drosophila embryo. We find that excess H3-tail that cannot be incorporated into chromatin is sufficient to shorten the embryonic cell cycle and reduce the activity of Chk1 in vitro and in vivo. Removal of the Chk1 phosphosite in H3 abolishes its ability to regulate the cell cycle. Mathematical modeling quantitatively supports a mechanism where changes in H3 nuclear concentrations over the final cell cycles leading up to the MBT regulate Chk1-dependent cell cycle slowing. We provide a novel mechanism for Chk1 regulation by H3, which is crucial for proper cell cycle remodeling during early embryogenesis.

scholarly journals The highly conserved N-terminal domains of histones H3 and H4 are required for normal cell cycle progression

1991 ◽  
Vol 11 (8) ◽  
pp. 4111-4120
Author(s):  
B A Morgan ◽  
B A Mittman ◽  
M M Smith
Keyword(s):  
Cell Cycle ◽  
Normal Cell ◽  
Cell Cycle Progression ◽  
Histone H3 ◽  
Temperature Sensitive ◽  
Histone H4 ◽  
Cycle Progression ◽  
Terminal Domain ◽  
Normal Cell Cycle ◽  
Terminal Domains

The N-terminal domains of the histones H3 and H4 are highly conserved throughout evolution. Mutant alleles deleted for these N-terminal domains were constructed in vitro and examined for function in vivo in Saccharomyces cerevisiae. Cells containing a single deletion allele of either histone H3 or histone H4 were viable. Deletion of the N-terminal domain of histone H4 caused cells to become sterile and temperature sensitive for growth. The normal cell cycle progression of these cells was also altered, as revealed by a major delay in progression through the G2 + M periods. Deletion of the N-terminal domain of histone H3 had only minor effects on mating and the temperature-sensitive growth of mutant cells. However, like the H4 mutant, the H3 mutants had a significant delay in completing the G2 + M periods of the division cycle. Double mutants containing N-terminal domain deletions of both histone H3 and histone H4 were inviable. The phenotypes of cells subject to this synthetic lethality suggest that the N-terminal domains are required for functions essential throughout the cell division cycle and provide genetic evidence that histones are randomly distributed during chromosome replication.

scholarly journals Cyclic AMP‐induced loss of histone H3 phosphorylation and disruption of cell cycle progression mediated through a novel cAMP binding protein

2006 ◽  
Vol 20 (5) ◽  
Author(s):  
Rebecca Claire Chiffer ◽  
Sara K. Snyder ◽  
Pedro Rodriguez ◽  
Eric Anderson ◽  
Catharine L. Smith
Keyword(s):  
Cell Cycle ◽  
Cyclic Amp ◽  
Cell Cycle Progression ◽  
Binding Protein ◽  
Histone H3 ◽  
Cycle Progression ◽  
H3 Phosphorylation ◽  
Histone H3 Phosphorylation

scholarly journals β-N-Acetylglucosamine (O-GlcNAc) Is a Novel Regulator of Mitosis-specific Phosphorylations on Histone H3

2012 ◽  
Vol 287 (15) ◽  
pp. 12195-12203 ◽  
Author(s):  
Jerry J. Fong ◽  
Brenda L. Nguyen ◽  
Robert Bridger ◽  
Estela E. Medrano ◽  
Lance Wells ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Progression ◽  
Histone H3 ◽  
Mass Spectrometry Analysis ◽  
Post Translational Modification ◽  
Cycle Progression ◽  
Spectrometry Analysis ◽  
Biochemical Assays ◽  
M Phase ◽  
Nucleocytoplasmic Proteins

O-Linked β-N-acetylglucosamine, or O-GlcNAc, is a dynamic post-translational modification that cycles on and off serine and threonine residues of nucleocytoplasmic proteins. The O-GlcNAc modification shares a complex relationship with phosphorylation, as both modifications are capable of mutually inhibiting the occupation of each other on the same or nearby amino acid residue. In addition to diabetes, cancer, and neurodegenerative diseases, O-GlcNAc appears to play a significant role in cell growth and cell cycle progression, although the precise mechanisms are still not well understood. A recent study also found that all four core nucleosomal histones (H2A, H2B, H3, and H4) are modified with O-GlcNAc, although no specific sites on H3 were reported. Here, we describe that histone H3, a protein highly phosphorylated during mitosis, is modified with O-GlcNAc. Several biochemical assays were used to validate that H3 is modified with O-GlcNAc. Mass spectrometry analysis identified threonine 32 as a novel O-GlcNAc site. O-GlcNAc was detected at higher levels on H3 during interphase than mitosis, which inversely correlated with phosphorylation. Furthermore, increased O-GlcNAcylation was observed to reduce mitosis-specific phosphorylation at serine 10, serine 28, and threonine 32. Finally, inhibiting OGA, the enzyme responsible for removing O-GlcNAc, hindered the transition from G2 to M phase of the cell cycle, displaying a phenotype similar to preventing mitosis-specific phosphorylation on H3. Taken together, these data indicate that O-GlcNAcylation regulates mitosis-specific phosphorylations on H3, providing a mechanistic switch that orchestrates the G2-M transition of the cell cycle.

scholarly journals BubR1 is a spindle assembly checkpoint protein regulating meiotic cell cycle progression of mouse oocyte

Cell Cycle ◽  
2010 ◽  
Vol 9 (6) ◽  
pp. 1112-1121 ◽  
Author(s):  
Liang Wei ◽  
Xing-Wei Liang ◽  
Qing-Hua Zhang ◽  
Mo Li ◽  
Ju Yuan ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Progression ◽  
Spindle Assembly Checkpoint ◽  
Spindle Assembly ◽  
Mouse Oocyte ◽  
Meiotic Cell ◽  
Cycle Progression ◽  
Checkpoint Protein ◽  
Spindle Assembly Checkpoint Protein
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