HDAC1 negatively regulates selective mitotic chromatin binding of the Notch effector RBPJ in a KDM5A-dependent manner

The inner nuclear membrane is functionalized by diverse transmembrane proteins that associate with nuclear lamins and/or chromatin. When cells enter mitosis, membrane-chromatin contacts must be broken to allow for proper chromosome segregation; yet how this occurs remains ill-understood. Unexpectedly, we observed that an imbalance in the levels of the lamina-associated polypeptide 1 (LAP1), an activator of ER-resident Torsin AAA+-ATPases, causes a failure in membrane removal from mitotic chromatin, accompanied by chromosome segregation errors and changes in post-mitotic nuclear morphology. These defects are dependent on a hitherto unknown chromatin-binding region of LAP1 that we have delineated. LAP1-induced NE abnormalities are efficiently suppressed by expression of wild-type but not ATPase-deficient Torsins. Furthermore, a dominant-negative Torsin induces chromosome segregation defects in a LAP1-dependent manner. These results indicate that association of LAP1 with chromatin in the nucleus can be modulated by Torsins in the perinuclear space, shedding new light on the LAP1-Torsin interplay.

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Torsin ATPases influence chromatin interaction of the Torsin regulator LAP1

10.1101/2020.10.01.321869 ◽

2020 ◽

Author(s):

Naemi Luithle ◽

Jelmi uit de Bos ◽

Ruud Hovius ◽

Daria Maslennikova ◽

Renard Lewis ◽

...

Keyword(s):

Chromosome Segregation ◽

Dominant Negative ◽

Chromatin Interaction ◽

Dependent Manner ◽

Chromatin Binding ◽

Wild Type ◽

Nuclear Lamins ◽

Perinuclear Space ◽

Aaa Atpases ◽

Mitotic Chromatin

SummaryThe inner nuclear membrane is functionalized by diverse transmembrane proteins that associate with nuclear lamins and/or chromatin. When cells enter mitosis, membrane-chromatin contacts must be broken to allow for proper chromosome segregation; yet how this occurs remains ill-understood. Unexpectedly, we observed that an imbalance in the levels of the lamina-associated polypeptide 1 (LAP1), an activator of ER-resident Torsin AAA+-ATPases, causes a failure in membrane removal from mitotic chromatin, accompanied by chromosome segregation errors and changes in post-mitotic nuclear morphology. These defects are dependent on a hitherto unknown chromatin-binding region of LAP1 that we have delineated. LAP1-induced NE abnormalities are efficiently suppressed by expression of wild-type but not ATPase-deficient Torsins. Furthermore, a dominant-negative Torsin induces chromosome segregation defects in a LAP1-dependent manner. These results indicate that association of LAP1 with chromatin in the nucleus can be modulated by Torsins in the perinuclear space, shedding new light on the LAP1-Torsin interplay.

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The Trithorax group protein ASH1 requires a combination of BAH domain and AT hooks, but not the SET domain, for mitotic chromatin binding and survival

Chromosoma ◽

10.1007/s00412-021-00762-z ◽

2021 ◽

Author(s):

Philipp A. Steffen ◽

Christina Altmutter ◽

Eva Dworschak ◽

Sini Junttila ◽

Attila Gyenesei ◽

...

Keyword(s):

Transcriptional Profiling ◽

Histone H3 ◽

Chromatin Binding ◽

Set Domain ◽

Trithorax Group ◽

Trxg Protein ◽

Group Protein ◽

Bah Domain ◽

Mitotic Chromatin

AbstractThe Drosophila Trithorax group (TrxG) protein ASH1 remains associated with mitotic chromatin through mechanisms that are poorly understood. ASH1 dimethylates histone H3 at lysine 36 via its SET domain. Here, we identify domains of the TrxG protein ASH1 that are required for mitotic chromatin attachment in living Drosophila. Quantitative live imaging demonstrates that ASH1 requires AT hooks and the BAH domain but not the SET domain for full chromatin binding in metaphase, and that none of these domains are essential for interphase binding. Genetic experiments show that disruptions of the AT hooks and the BAH domain together, but not deletion of the SET domain alone, are lethal. Transcriptional profiling demonstrates that intact ASH1 AT hooks and the BAH domain are required to maintain expression levels of a specific set of genes, including several involved in cell identity and survival. This study identifies in vivo roles for specific ASH1 domains in mitotic binding, gene regulation, and survival that are distinct from its functions as a histone methyltransferase.

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Identification of two independent nucleosome-binding domains in the transcriptional co-activator SPBP

Biochemical Journal ◽

10.1042/bj20111230 ◽

2012 ◽

Vol 442 (1) ◽

pp. 65-75 ◽

Cited By ~ 19

Author(s):

Sagar Darvekar ◽

Sylvia Sagen Johnsen ◽

Agnete Bratsberg Eriksen ◽

Terje Johansen ◽

Eva Sjøttem

Keyword(s):

Transcription Factors ◽

Dependent Manner ◽

Chromatin Binding ◽

Binding Region ◽

Interaction Domain ◽

Binding Domains ◽

Element Binding Protein ◽

Inducible Protein ◽

Responsive Element ◽

Nucleosome Binding

Transcriptional regulation requires co-ordinated action of transcription factors, co-activator complexes and general transcription factors to access specific loci in the dense chromatin structure. In the present study we demonstrate that the transcriptional co-regulator SPBP [stromelysin-1 PDGF (platelet-derived growth factor)-responsive element binding protein] contains two independent chromatin-binding domains, the SPBP-(1551–1666) region and the C-terminal extended PHD [ePHD/ADD (extended plant homeodomain/ATRX-DNMT3-DNMT3L)] domain. The region 1551–1666 is a novel core nucleosome-interaction domain located adjacent to the AT-hook motif in the DNA-binding domain. This novel nucleosome-binding region is critically important for proper localization of SPBP in the cell nucleus. The ePHD/ADD domain associates with nucleosomes in a histone tail-dependent manner, and has significant impact on the dynamic interaction between SPBP and chromatin. Furthermore, SPBP and its homologue RAI1 (retinoic-acid-inducible protein 1), are strongly enriched on chromatin in interphase HeLa cells, and both proteins display low nuclear mobility. RAI1 contains a region with homology to the novel nucleosome-binding region SPBP-(1551–1666) and an ePHD/ADD domain with ability to bind nucleosomes. These results indicate that the transcriptional co-regulator SPBP and its homologue RAI1 implicated in Smith–Magenis syndrome and Potocki–Lupski syndrome both belong to the expanding family of chromatin-binding proteins containing several domains involved in specific chromatin interactions.

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In vivo Polycomb kinetics and mitotic chromatin binding distinguish stem cells from differentiated cells

Genes & Development ◽

10.1101/gad.184648.111 ◽

2012 ◽

Vol 26 (8) ◽

pp. 857-871 ◽

Cited By ~ 51

Author(s):

J. P. Fonseca ◽

P. A. Steffen ◽

S. Muller ◽

J. Lu ◽

A. Sawicka ◽

...

Keyword(s):

Stem Cells ◽

Chromatin Binding ◽

Differentiated Cells ◽

Mitotic Chromatin

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Contribution of CAF-I to Anaphase-Promoting-Complex-Mediated Mitotic Chromatin Assembly in Saccharomyces cerevisiae

Eukaryotic Cell ◽

10.1128/ec.4.4.673-684.2005 ◽

2005 ◽

Vol 4 (4) ◽

pp. 673-684 ◽

Cited By ~ 11

Author(s):

Troy A. A. Harkness ◽

Terra G. Arnason ◽

Charmaine Legrand ◽

Marnie G. Pisclevich ◽

Gerald F. Davies ◽

...

Keyword(s):

Chromatin Assembly ◽

Dependent Manner ◽

Anaphase Promoting Complex ◽

Mitotic Progression ◽

Independent Manner ◽

Expression Of Genes ◽

Genes Encoding ◽

Multiple Copies ◽

The Individual ◽

Mitotic Chromatin

ABSTRACT The anaphase-promoting complex (APC) is required for mitotic progression and genomic stability. Recently, we demonstrated that the APC is also required for mitotic chromatin assembly and longevity. Here, we investigated the role the APC plays in chromatin assembly. We show that apc5 CA mutations genetically interact with the CAF-I genes as well as ASF1, HIR1, and HIR2. When present in multiple copies, the individual CAF-I genes, CAC1, CAC2, and MSI1, suppress apc5 CA phenotypes in a CAF-1- and Asf1p-independent manner. CAF-I and the APC functionally overlap, as cac1Δ cac2Δ msi1Δ (caf1Δ) cells expressing apc5 CA exhibit a phenotype more severe than that of apc5 CA or caf1Δ. The Ts− phenotypes observed in apc5 CA and apc5 CA caf mutants may be rooted in compromised histone metabolism, as coexpression of histones H3 and H4 suppressed the Ts− defects. Synthetic genetic interactions were also observed in apc5 CA asf1Δ cells. Furthermore, increased expression of genes encoding Asf1p, Hir1p, and Hir2p suppressed the apc5 CA Ts− defect in a CAF-I-dependent manner. Together, these results suggest the existence of a complex molecular mechanism controlling APC-dependent chromatin assembly. Our data suggest the APC functions with the individual CAF-I subunits, Asf1p, and the Hir1p and Hir2p proteins. However, Asf1p and an intact CAF-I complex are dispensable for CAF-I subunit suppression, whereas CAF-I is necessary for ASF1, HIR1, and HIR2 suppression of apc5 CA phenotypes. We discuss the implications of our observations.

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SirT7 auto-ADP-ribosylation regulates glucose starvation response through macroH2A1.1

10.1101/719559 ◽

2019 ◽

Author(s):

Nicolás G. Simonet ◽

Joshua K. Thackray ◽

Berta N. Vazquez ◽

Alessandro Ianni ◽

Maria Espinosa-Alcantud ◽

...

Keyword(s):

Calorie Restriction ◽

Genome Stability ◽

Genotoxic Stress ◽

Dependent Manner ◽

Chromatin Binding ◽

Glucose Starvation ◽

Starvation Response ◽

Domain Specific ◽

Intergenic Regions ◽

Adp Ribosyltransferase

AbstractSirtuins are key players in the response to oxidative, metabolic and genotoxic stress, and are involved in genome stability, metabolic homeostasis and aging. Originally described as NAD+-dependent deacetylases, some sirtuins are also characterized by a poorly understood mono-ADP-ribosyltransferase (mADPRT) activity. Here we report that the deacetylase SirT7 is a dual sirtuin as it also features auto-mADPRT activity. Molecular and structural evidence suggests that this novel activity occurs at a second previously undefined active site that is physically separated in another domain. Specific abrogation of this activity alters SirT7 chromatin distribution, suggesting a role for this modification in SirT7 chromatin binding specificity. We uncover an epigenetic pathway by which ADP-ribosyl-SirT7 is recognized by the ADP-ribose reader macroH2A1.1, a histone variant involved in chromatin organization, metabolism and differentiation. Glucose starvation (GS) boosts this interaction and promotes SirT7 relocalization to intergenic regions in a macroH2A1-dependent manner. Both SirT7 activities are in turn required to promote GS-dependent enrichment of macroH2A1 in a subset of nearby genes, which results in their specific up- or downregulation. Consistently, the expression changes of these genes associated to calorie restriction (CR) or aging are abrogated in SirT7-/- mice, reinforcing the link between Sirtuins, CR and aging. Our work provides a novel perspective about sirtuin duality and suggests a key role for SirT7/macroH2A1.1 axis in mammalian glucose homeostasis, calorie restriction signaling and aging.

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Herpes Simplex Virus Tegument Protein VP22 Contains Overlapping Domains for Cytoplasmic Localization, Microtubule Interaction, and Chromatin Binding

Journal of Virology ◽

10.1128/jvi.76.10.4961-4970.2002 ◽

2002 ◽

Vol 76 (10) ◽

pp. 4961-4970 ◽

Cited By ~ 38

Author(s):

Ana Martin ◽

Peter O'Hare ◽

John McLauchlan ◽

Gillian Elliott

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Fluorescent Protein ◽

Tegument Protein ◽

Cytoplasmic Localization ◽

Chromatin Binding ◽

Microtubule Network ◽

Simplex Virus ◽

Protein Vp22 ◽

Mitotic Chromatin

ABSTRACT We have previously shown that the 301-amino-acid herpes simplex virus tegument protein VP22 exhibits a range of subcellular localization patterns when expressed in isolation from other virus proteins. By using live-cell analysis of cells expressing green fluorescent protein (GFP)-tagged VP22 we have shown that when VP22 is first expressed in the cell it localizes to the cytoplasm, where, when present at high enough concentrations, it can assemble onto microtubules, causing them to bundle and become highly stabilized. In addition we have shown that when a cell expressing VP22 enters mitosis, the cytoplasmic population of VP22 translocates to the nucleus, where it efficiently binds mitotic chromatin. Here we have investigated the specific regions of the VP22 open reading frame required for these properties. Using GFP-VP22 as our starting molecule, we have constructed a range of N- and C-terminal truncations and analyzed their localization patterns in live cells. We show that the C-terminal 242 residues of VP22 are sufficient to induce microtubule bundling. Within this subregion, the C-terminal 89 residues contain a signal for cytoplasmic localization of the protein, while a larger region comprising the C-terminal 128 residues of the VP22 protein is required for mitotic chromatin binding. Furthermore, a central 100-residue domain of VP22 maintains the ability to bind microtubules without inducing bundling, suggesting that additional regions flanking this microtubule binding domain may be required to alter the microtubule network. Hence, the signals involved in dictating the complex localization patterns of VP22 are present in overlapping regions of the protein.

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Quantitative in vivo analysis of chromatin binding of Polycomb and Trithorax group proteins reveals retention of ASH1 on mitotic chromatin

Nucleic Acids Research ◽

10.1093/nar/gkt217 ◽

2013 ◽

Vol 41 (10) ◽

pp. 5235-5250 ◽

Cited By ~ 33

Author(s):

Philipp A. Steffen ◽

João Pedro Fonseca ◽

Cornelia Gänger ◽

Eva Dworschak ◽

Tobias Kockmann ◽

...

Keyword(s):

Chromatin Binding ◽

Trithorax Group ◽

In Vivo Analysis ◽

Trithorax Group Proteins ◽

Mitotic Chromatin

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NEIL1 and NEIL2 Are Recruited as Potential Backup for OGG1 upon OGG1 Depletion or Inhibition by TH5487

International Journal of Molecular Sciences ◽

10.3390/ijms22094542 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4542

Author(s):

Bishoy M. F. Hanna ◽

Maurice Michel ◽

Thomas Helleday ◽

Oliver Mortusewicz

Keyword(s):

Dna Damage ◽

Base Excision Repair ◽

Excision Repair ◽

Dependent Manner ◽

Chromatin Binding ◽

Dna Glycosylases ◽

Major Pathway ◽

Base Excision ◽

Dose Dependent ◽

Dna Substrate

DNA damage caused by reactive oxygen species may result in genetic mutations or cell death. Base excision repair (BER) is the major pathway that repairs DNA oxidative damage in order to maintain genomic integrity. In mammals, eleven DNA glycosylases have been reported to initiate BER, where each recognizes a few related DNA substrate lesions with some degree of overlapping specificity. 7,8-dihydro-8-oxoguanine (8-oxoG), one of the most abundant DNA oxidative lesions, is recognized and excised mainly by 8-oxoguanine DNA glycosylase 1 (OGG1). Further oxidation of 8-oxoG generates hydantoin lesions, which are recognized by NEIL glycosylases. Here, we demonstrate that NEIL1, and to a lesser extent NEIL2, can potentially function as backup BER enzymes for OGG1 upon pharmacological inhibition or depletion of OGG1. NEIL1 recruitment kinetics and chromatin binding after DNA damage induction increase in cells treated with OGG1 inhibitor TH5487 in a dose-dependent manner, whereas NEIL2 accumulation at DNA damage sites is prolonged following OGG1 inhibition. Furthermore, depletion of OGG1 results in increased retention of NEIL1 and NEIL2 at damaged chromatin. Importantly, oxidatively stressed NEIL1- or NEIL2-depleted cells show excessive genomic 8-oxoG lesions accumulation upon OGG1 inhibition, suggesting a prospective compensatory role for NEIL1 and NEIL2. Our study thus exemplifies possible backup mechanisms within the base excision repair pathway.

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