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1
ING4 mediates crosstalk between histone H3 K4 trimethylation and H3 acetylation to attenuate cellular transformation.
2009-01-30

Aberrations in chromatin dynamics play a fundamental role in tumorigenesis, yet relatively little is known of the molecular mechanisms linking histone lysine methylation to neoplastic disease. ING4 (Inhibitor of Growth 4) is a native subunit of an HBO1 histone acetyltransferase (HAT) complex and a tumor suppressor protein. Here we show a critical role for ...

PubMed

2
Quinoline Derivative MC1626, a Putative GCN5 Histone Acetyltransferase (HAT) Inhibitor, Exhibits HAT-Independent Activity against Toxoplasma gondii?
2007-03-18

We report that quinoline derivative MC1626, first described as an inhibitor of the histone acetyltransferase (HAT) GCN5, is active against the protozoan parasite Toxoplasma gondii in vitro. However, MC1626 does not inhibit Toxoplasma GCN5 HATs or reduce HAT-mediated activity; rather, this quinoline may target the ...

PubMed Central

3
HBO1 histone acetylase activity is essential for DNA replication licensing and inhibited by geminin
2010-01-15

HBO1, an H4-specific histone acetylase, is a co-activator of the DNA replication licensing factor Cdt1. HBO1 acetylase activity is required for licensing, because a HAT-defective mutant of HBO1 bound at origins is unable to load the MCM complex. H4 acetylation at origins is cell-cycle ...

PubMed Central

4
Inhibition of histone acetyltransferase activity by anacardic acid sensitizes tumor cells to ionizing radiation.
2006-07-10

Histone acetyltransferases (HATs) regulate transcription, chromatin structure and DNA repair. Here, we utilized a novel HAT inhibitor, anacardic acid, to examine the role of HATs in the DNA damage response. Anacardic acid inhibits the Tip60 HAT in vitro, and blocks the Tip60-dependent ...

PubMed

5
Identification of long chain alkylidenemalonates as novel small molecule modulators of histone acetyltransferases.
2008-04-11

Pentadecylidenemalonate 1b, a simplified analogue of anacardic acid, was identified as the first mixed activator/inhibitor of histone acetyltransferases (HATs). It potentiates PCAF HAT activity while inhibiting those of p300/CBP and recombinant CBP. The remarkable apoptotic effect together with the ability to selectively acetylate ...

PubMed

6
Type B Histone Acetyltransferase Hat1p Participates in Telomeric Silencing
2000-10-01

Hat1p and Hat2p are the two subunits of a type B histone acetyltransferase from Saccharomyces cerevisiae that acetylates free histone H4 on lysine 12 in vitro. However, the role for these gene products in chromatin function has been unclear, as deletions of the HAT1 and/or HAT2 gene displayed ...

PubMed Central

7
Regulation of Replication Licensing by Acetyltransferase Hbo1
2006-02-01

The initiation of DNA replication is tightly regulated in eukaryotic cells to ensure that the genome is precisely duplicated once and only once per cell cycle. This is accomplished by controlling the assembly of a prereplicative complex (pre-RC) which involves the sequential binding to replication origins of the origin recognition complex (ORC), Cdc6/Cdc18, Cdt1, and the minichromosome maintenance ...

PubMed Central

8
The SV40 T antigen modulates CBP histone acetyltransferase activity
2003-06-15

Histone acetyltransferases (HATs) play a key role in transcription control, cell proliferation and differentiation by modulating chromatin structure; however, little is known about their own regulation. Here we show that expression of the viral oncoprotein SV40 T antigen increases histone acetylation and global cellular HAT activities. ...

PubMed Central

9
Mediator-nucleosome interaction.
2000-07-01

Mediator, a multiprotein complex involved in the regulation of RNA polymerase II transcription, binds to nucleosomes and acetylates histones. Three lines of evidence identify the Nut1 subunit of Mediator as responsible for the histone acetyltransferase (HAT) activity. An "in-gel" HAT assay reveals a single band of the appropriate size. ...

PubMed

10
Chemical biology of histone acetyltransferase natural compounds modulators.
2011-01-01

Histone acetyltransferases (HATs) are a class of epigenetic enzymes crucial for chromatin restructuring and transcriptional regulation in eukaryotic cells, thus being a promising target for therapeutic development. Nonetheless, differently from histone deacetylases (HDACs) inhibitors, there is still paucity of small-molecule modulators of ...

PubMed

11
Improved inhibition of the histone acetyltransferase PCAF by an anacardic acid derivative.
2010-07-03

Several lines of evidence indicate that histone acetyltransferases (HATs) are novel drug targets for treatment of diseases like, for example, cancer and inflammation. The natural product anacardic acid is a starting point for development of small molecule inhibitors of the histone acetyltransferase (HAT) p300/CBP ...

PubMed

12
Synthesis and biological testing of novel pyridoisothiazolones as histone acetyltransferase inhibitors.
2011-02-02

We present a combination of database screening, synthesis and in vitro testing to identify novel histone acetyltransferase (HAT) inhibitors. The National Cancer Institute compound collection (NCI) and several commercial databases were filtered by similarity-based virtual screening to find new HAT inhibitors. Employing the recombinant ...

PubMed

13
Structure and Biochemical Characterization of Protein Acetyltransferase from Sulfolobus solfataricus
2009-09-02

The Sulfolobus solfataricus protein acetyltransferase (PAT) acetylates ALBA, an abundant nonspecific DNA-binding protein, on Lys{sup 16} to reduce its DNA affinity, and the Sir2 deacetylase reverses the modification to cause transcriptional repression. This represents a 'primitive' model for chromatin regulation analogous to histone modification in ...

Energy Citations Database

14
Microarray Analysis Uncovers a Role for Tip60 in Nervous System Function and General Metabolism
2011-04-11

BackgroundTip60 is a key histone acetyltransferase (HAT) enzyme that plays a central role in diverse biological processes critical for general cell function; however, the chromatin-mediated cell-type specific developmental pathways that are dependent exclusively upon the HAT activity of Tip60 remain to be explored.Methods and ...

PubMed Central

15
HBO1 is required for H3K14 acetylation and normal transcriptional activity during embryonic development.
2010-12-13

We report here that the MYST histone acetyltransferase HBO1 (histone acetyltransferase bound to ORC; MYST2/KAT7) is essential for postgastrulation mammalian development. Lack of HBO1 led to a more than 90% reduction of histone 3 lysine 14 (H3K14) acetylation, whereas no reduction of acetylation was detected at ...

PubMed

16
HBO1 Is Required for H3K14 Acetylation and Normal Transcriptional Activity during Embryonic Development?
2011-02-13

We report here that the MYST histone acetyltransferase HBO1 (histone acetyltransferase bound to ORC; MYST2/KAT7) is essential for postgastrulation mammalian development. Lack of HBO1 led to a more than 90% reduction of histone 3 lysine 14 (H3K14) acetylation, whereas no reduction of acetylation was detected at ...

PubMed Central

17
Histone acetylation modulation by small molecules: a chemical approach.
2010-05-21

Histone acetyltransferases (HATs) are enzymes able to acetylate lysine side chains of histones. They play essential roles in normal cell function as well as in pathogenesis of a broad set of diseases, including multiple cancers, HIV, diabetes mellitus, and neurodegenerative disorders. Moreover, several HATs are able to acetylate ...

PubMed

18
Virtual ligand screening of the p300/CBP histone acetyltransferase: identification of a selective small molecule inhibitor.
2010-05-28

The histone acetyltransferase (HAT) p300/CBP is a transcriptional coactivator implicated in many gene regulatory pathways and protein acetylation events. Although p300 inhibitors have been reported, a potent, selective, and readily available active-site-directed small molecule inhibitor is not yet known. Here we use a structure-based, in silico screening ...

PubMed

19
Virtual Ligand Screening of the p300/CBP Histone Acetyltransferase: Identification of a Selective Small Molecule Inhibitor
2010-05-28

SummaryThe histone acetyltransferase (HAT) p300/CBP is a transcriptional coactivator implicated in many gene regulatory pathways and protein acetylation events. While p300 inhibitors have been reported, a potent, selective, and readily available active-site directed small molecule inhibitor is not yet known. Here we use a structure-based, in silico ...

PubMed Central

20
p300 Acetyltransferase activity differentially regulates the localization and activity of the FOXO homologues in skeletal muscle.
2011-03-09

The Forkhead Box O (FOXO) transcription factors regulate diverse cellular processes, and in skeletal muscle are both necessary and sufficient for muscle atrophy. Although the regulation of FOXO by Akt is well evidenced in skeletal muscle, the current study demonstrates that FOXO is also regulated in muscle via the histone acetyltransferase (HAT) activities ...

PubMed

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21
Heparanase-mediated Loss of Nuclear Syndecan-1 Enhances Histone Acetyltransferase (HAT) Activity to Promote Expression of Genes That Drive an Aggressive Tumor Phenotype.
2011-07-11

Heparanase acts as a master regulator of the aggressive tumor phenotype in part by enhancing expression of proteins known to drive tumor progression (e.g. VEGF, MMP-9, hepatocyte growth factor (HGF), and RANKL). However, the mechanism whereby this enzyme regulates gene expression remains unknown. We previously reported that elevation of heparanase levels in myeloma cells causes a dramatic ...

PubMed

22
Characterization of novel inhibitors of histone acetyltransferases.
2007-09-01

Modification of proteins by histone acetyltransferases (HAT) or histone deacetylases plays an important role in the control of gene expression, and its dysregulation has been linked to malignant transformation and other diseases. Although histone deacetylase inhibitors have been extensively studied and several are currently in clinical trials, there is ...

PubMed

23
Fungal Rtt109 histone acetyltransferase is an unexpected structural homolog of metazoan p300/CBP
2008-06-22

Rtt109, also known as KAT11, is a recently characterized fungal-specific histone acetyltransferase (HAT) that modifies histone H3 lysine 56 (H3K56) to promote genome stability. Rtt109 does not show sequence conservation with other known HATs and depends on association with either of two histone chaperones, Asf1 or Vps75, for ...

PubMed Central

24
Fungal Rtt109 Histone Acetyltransferase is an Unexpected Structural Homolog of Metazoan p300/CBP
2008-01-01

Rtt109, also known as KAT11, is a recently characterized fungal-specific histone acetyltransferase (HAT) that modifies histone H3 lysine 56 (H3K56) to promote genome stability. Rtt109 does not show sequence conservation with other known HATs and depends on association with either of two histone chaperones, Asf1 or Vps75, for ...

Energy Citations Database

25
Effect of different exercise protocols on histone acetyltransferases and histone deacetylases activities in rat hippocampus.
2011-07-01

Regular and moderate exercise has been considered an interesting neuroprotective strategy. Although the mechanisms by which physical exercise alters brain function are not clear, it appears that neuroprotective properties of exercise could be related to chromatin remodeling, specifically the induction of histone acetylation through modulation of histone deacetylases (HDAC) and histone ...

PubMed

26
Nitric oxide-mediated histone hyperacetylation in oral cancer: target for a water-soluble HAT inhibitor, CTK7A.
2010-08-27

Altered histone acetylation is associated with several diseases, including cancer. We report here that, unlike in most cancers, histones are found to be highly hyperacetylated in oral squamous cell carcinoma (OSCC; oral cancer) patient samples. Mechanistically, overexpression, as well as enhanced autoacetylation, of p300 induced by nucleophosmin (NPM1) and glyceraldehyde 3-phosphate dehydrogenase ...

PubMed

27
HATs and HDACs in neurodegeneration: a tale of disconcerted acetylation homeostasis
2006-04-01

Gradual disclosure of the molecular basis of selective neuronal apoptosis during neurodegenerative diseases reveals active participation of acetylating and deacetylating agents during the process. Several studies have now successfully manipulated neuronal vulnerability by influencing the dose and enzymatic activity of histone acetyltransferases (HATs) and ...

PubMed Central

28
Inhibition of Histone Acetyltransferase by Glycosaminoglycans
2008-09-01

Histone acetyltransferases (HATs) are a class of enzymes that participate in modulating chromatin structure and gene expression. Altered HAT activity has been implicated in a number of diseases, yet little is known about the regulation of HATs. In this study, we report that glycosaminoglycans are potent inhibitors ...

PubMed Central

29
A Role for Gcn5-Mediated Global Histone Acetylation in Transcriptional Regulation
2006-03-01

Transcriptional activators often require histone acetyltransferases (HATs) for full activity. The common explanation is that activators directly recruit HATs to gene promoters to locally hyperacetylate histones and thereby facilitate transcription complex formation. However, in addition to being targeted to specific loci, ...

PubMed Central

30
Lessons from genome-wide studies: an integrated definition of the coactivator function of histone acetyl transferases
2010-10-20

Histone acetylation is one of the key regulatory mechanisms controlling transcriptional activity in eukaryotic cells. In higher eukaryotes, a number of nuclear histone acetyltransferase (HAT) enzymes have been identified, most of which are part of a large multisubunit complex. This diversity, combined with the large number of potentially acetylable lysines ...

PubMed Central

31
HBO1 histone acetylase is a coactivator of the replication licensing factor Cdt1
2008-10-01

HBO1 histone acetylase is important for DNA replication licensing. In human cells, HBO1 associates with replication origins specifically during the G1 phase of the cell cycle in a manner that depends on the replication licensing factor Cdt1, but is independent of the Cdt1 repressor Geminin. ...

PubMed Central

32
Global Assessment of Combinatorial Post-translational Modification of Core Histones in Yeast Using Contemporary

are: PTM, post-translational modification; HAT, his- tone acetyltransferase; ECD, electron capture dissociation (ECD) for tandem mass spectrometry (23, 24). Recently, this general approach has been demonstrated" of acetylation for H4) (28). Besides characterizing all core histones, ECD analysis of the H3 tail from wild

E-print Network

33
Acetylation of Histones and Transcription-Related Factors
2000-06-01

The state of chromatin (the packaging of DNA in eukaryotes) has long been recognized to have major effects on levels of gene expression, and numerous chromatin-altering strategies�including ATP-dependent remodeling and histone modification�are employed in the cell to bring about transcriptional regulation. Of these, histone acetylation is one of the best characterized, as recent years have ...

PubMed Central

34
Repression of GCN5 Histone Acetyltransferase Activity via Bromodomain-Mediated Binding and Phosphorylation by the Ku�DNA-Dependent Protein Kinase Complex
1998-03-01

GCN5, a putative transcriptional adapter in humans and yeast, possesses histone acetyltransferase (HAT) activity which has been linked to GCN5�s role in transcriptional activation in yeast. In this report, we demonstrate a functional interaction between human GCN5 (hGCN5) and the DNA-dependent protein kinase (DNA-PK) holoenzyme. Yeast two-hybrid ...

PubMed Central

35
Procyanidin B3, an inhibitor of histone acetyltransferase, enhances the action of antagonist for prostate cancer cells via inhibition of p300-dependent acetylation of androgen receptor.
2011-01-01

Increasing evidence suggests that AR (androgen receptor) acetylation is critical for prostate cancer cell growth. In the present study, we identified Pro-B3 (procyanidin B3) as a specific HAT (histone acetyltransferase) inhibitor. Pro-B3 selectively inhibited the activity of HATs, but not other epigenetic enzymes. Pro-B3 substantially ...

PubMed

36
The Structural Basis of Protein Acetylation by the p300/CBP Transcriptional Coactivator
2008-01-01

The transcriptional coactivator p300/CBP (CREBBP) is a histone acetyltransferase (HAT) that regulates gene expression by acetylating histones and other transcription factors. Dysregulation of p300/CBP HAT activity contributes to various diseases including cancer. Sequence alignments, enzymology experiments and inhibitor studies on ...

Energy Citations Database

37
Genome-wide mapping of HATs and HDACs reveals distinct functions in active and inactive genes
2009-08-20

Histone acetyltransferases (HATs) and histone deacetylases (HDACs) function antagonistically to control histone acetylation states that are crucial to many cellular processes. We describe here genome-wide mapping experiments that reveal that both HATs (CBP, p300, PCAF, Tip60, MOF) and HDACs (HDAC1, HDAC2, HDAC3, HDAC6) on chromatin are ...

PubMed Central

38
Transcriptional Regulation of the MDR1 Gene by Histone Acetyltransferase and Deacetylase Is Mediated by NF-Y
1998-07-01

Recent studies have shown that the histone-modifying enzymes histone acetyltransferase (HAT) and histone deacetylase (HDAC) are involved in transcriptional activation and repression, respectively. However, little is known about the endogenous genes that are regulated by these enzymes or how specificity is achieved. In the present report, we demonstrate ...

PubMed Central

39
SAGA-associated Sgf73p facilitates formation of the preinitiation complex assembly at the promoters either in a HAT-dependent or independent manner in vivo.
2006-11-07

Although Sgf73p, a yeast homologue of human Sca7p, has recently been implicated as a new component of Spt-Ada-Gcn5-acetyltransferase (SAGA), its association with SAGA and functional role in regulation of transcription remain unknown in vivo. Here, using a chromatin immunoprecipitation (ChIP) assay, we show in vivo that, like SAGA, Sgf73p is recruited to the upstream activating ...

PubMed

40
Multitasking C2H2 Zinc Fingers Link Zac DNA Binding to Coordinated Regulation of p300-Histone Acetyltransferase Activity
2006-07-01

Zac is a C2H2 zinc finger protein that regulates apoptosis and cell cycle arrest through DNA binding and transactivation. The coactivator proteins p300/CBP enhance transactivation through their histone acetyltransferase (HAT) activity by modulating chromatin structure. Here, we show that p300 increases Zac ...

PubMed Central

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41
Activation of p300 histone acetyltransferase by small molecules altering enzyme structure: probed by surface-enhanced Raman spectroscopy.
2007-04-07

Reversible acetylation of nucleosomal histones and nonhistone proteins play pivotal roles in the regulation of all the DNA templated phenomenon. Dysfunction of the enzymes involved in the acetylation/deacetylation leads to several diseases. Therefore, these enzymes are the targets for new generation therapeutics. Here, we report the synthesis of trifluoromethyl phenyl benzamides and their effect ...

PubMed

42
Synthesis of benzamides related to anacardic acid and their histone acetyltransferase (HAT) inhibitory activities.
2008-09-01

A group of benzamides related to anacardic acid amide CTPB with alkyl chains of defined length were prepared by a five-step sequence starting from 2,6-dihydroxybenzoic acid, and their activities were compared with those reported for the HAT inhibitor anacardic acid (AA). The subset of 4-cyano-3-trifluoromethylphenylbenzamides with shorter chains exhibited activities similar to ...

PubMed

43
Putting the �HAT� back on survival signalling: the promises and challenges of HDAC inhibition in the treatment of neurological conditions
2009-05-01

Decreased histone acetyltransferase activity and transcriptional dysfunction have been implicated in almost all neurodegenerative conditions. Increasing net histone acetyltransferase activity through inhibition of the histone deacetylases (HDACs) has been shown to be an effective strategy to delay or halt progression of neurological disease in cellular and ...

PubMed Central

44
Modulating substrate specificity of histone acetyltransferase with unnatural amino acids.
2011-08-31

Controlling the substrate specificity of enzymes is a major challenge for protein engineers. Here we explore the effects of residue-specific incorporation of ortho-, meta- and para-fluorophenylalanine (oFF, mFF, pFF) on the selectivity of human histone acetyltransferase (HAT) protein, p300/CBP associated factor (PCAF). Varying the position of the fluorine ...

PubMed

45
Histone acetyltransferase hALP and nuclear membrane protein hsSUN1 function in de-condensation of mitotic chromosomes.
2007-07-13

Replicated mammalian chromosomes condense to segregate during anaphase, and they de-condense at the conclusion of mitosis. Currently, it is not understood what the factors and events are that specify de-condensation. Here, we demonstrate that chromosome de-condensation needs the function of an inner nuclear membrane (INM) protein hsSUN1 and a membrane-associated histone ...

PubMed

46
The Histone Acetyltransferase PCAF Associates with Actin and hnRNP U for RNA Polymerase II Transcription?
2008-10-18

Actin is a key regulator of RNA polymerase (pol) II transcription. In complex with specific hnRNPs, it has been proposed that actin functions to recruit pol II coactivators during the elongation of nascent transcripts. Here, we show by affinity chromatography, protein-protein interaction assays, and biochemical fractionation of nuclear extracts that the histone ...

PubMed Central

47
Small molecule inhibitors of histone acetyltransferase Tip60
2010-12-07

Tip60 is a key member of the MYST family of histone acetyltransferases and involved in a broad spectrum of cellular pathways and disease conditions. So far, small molecule inhibitors of Tip60 and other members of MYST HATs are rarely reported. To discover new small molecule inhibitors of Tip60 as mechanistic tools for functional study and as chemical leads ...

PubMed Central

48
Crystal structure of tabtoxin resistance protein complexed with acetyl coenzyme A reveals the mechanism for {beta}-lactam acetylation.
2003-01-31

Tabtoxin resistance protein (TTR) is an enzyme that renders tabtoxin-producing pathogens, such as Pseudomonas syringae, tolerant to their own phytotoxins. Here, we report the crystal structure of TTR complexed with its natural cofactor, acetyl coenzyme A (AcCoA), to 1.55 {angstrom} resolution. The binary complex forms a characteristic 'V' shape for substrate binding and contains ...

Energy Citations Database

49
Catalytic-Site Mutations in the MYST Family Histone Acetyltransferase Esa1
2008-03-01

Esa1 is the only essential histone acetyltransferase (HAT) in budding yeast. It is the catalytic subunit of at least two multiprotein complexes, NuA4 and Piccolo NuA4 (picNuA4), and its essential function is believed to be its catalytic HAT activity. To examine the role of Esa1 in DNA damage repair, we isolated viable esa1 mutants with ...

PubMed Central

50
Bisubstrate Inhibitors of the MYST HATs Esa1 and Tip60.
2008-12-24

Esa1 (essential Sas2-related acetyltransferase 1) and Tip60 (HIV-1 TAT-interactive protein, 60 kDa) are key members of the MYST family of histone acetyltransferases (HATs) and play important functions in many cellular processes. In this work, we designed, synthesized and evaluated a series of substrate-based analogs for the inhibition ...

PubMed

51
Cytotoxicity mediated by histone deacetylase inhibitors in cancer cells: mechanisms and potential clinical implications.
2009-06-09

Aberrant expression of epigenetic regulators of gene expression contributes to initiation and progression of cancer. During recent years, considerable research efforts have focused on the role of histone acetyltransferases (HATs) and histone deacetylases (HDACs) in cancer cells, and the identification of pharmacologic agents that modulate gene expression ...

PubMed

52
MRG15 activates the cdc2 promoter via histone acetylation in human cells.
2011-02-14

Chromatin remodeling is required for transcriptional activation and repression. MRG15 (MORF4L1), a chromatin modulator, is a highly conserved protein and is present in complexes containing histone acetyltransferases (HATs) as well as histone deacetylases (HDACs). Loss of expression of MRG15 in mice and Drosophila results in embryonic lethality and ...

PubMed

53
Histone deacetylase inhibitors, valproic acid and trichostatin-A induce apoptosis and affect acetylation status of p53 in ERG-positive prostate cancer cells.
2011-04-21

An ETS family member, ETS Related Gene (ERG) is involved in the Ewing family of tumors as well as leukemias. Rearrangement of the ERG gene with the TMPRSS2 gene has been identified in the majority of prostate cancer patients. Additionally, overexpression of ERG is associated with unfavorable prognosis in prostate cancer patients similar to leukemia patients. Histone ...

PubMed

54
PDCD5 interacts with Tip60 and functions as a cooperator in acetyltransferase activity and DNA damage-induced apoptosis.
2009-04-01

Tip60 is a histone acetyltransferase (HAT) involved in the acetyltransferase activity and the cellular response to DNA damage. Here, we show that programmed cell death 5 (PDCD5), a human apoptosis-related protein, binds to Tip60 and enhances the stability of Tip60 protein in unstressed conditions. The binding amount of PDCD5 and Tip60 ...

PubMed

55
PDCD5 Interacts with Tip60 and Functions as a Cooperator in Acetyltransferase Activity and DNA Damage-Induced Apoptosis12
2009-04-01

Tip60 is a histone acetyltransferase (HAT) involved in the acetyltransferase activity and the cellular response to DNA damage. Here, we show that programmed cell death 5 (PDCD5), a human apoptosis-related protein, binds to Tip60 and enhances the stability of Tip60 protein in unstressed conditions. The binding amount of PDCD5 and Tip60 ...

PubMed Central

56
Subregion-Specific p300 Conditional Knock-Out Mice Exhibit Long-Term Memory Impairments
2011-03-01

Histone acetylation plays a critical role during long-term memory formation. Several studies have demonstrated that the histone acetyltransferase (HAT) CBP is required during long-term memory formation, but the involvement of other HAT proteins has not been extensively investigated. The HATs CBP and p300 have at ...

ERIC Educational Resources Information Center

57
H4 replication-dependent diacetylation and Hat1 promote S-phase chromatin assembly in vivo.
2010-11-30

While specific posttranslational modification patterns within the H3 and H4 tail domains are associated with the S-phase, their actual functions in replication-dependent chromatin assembly have not yet been defined. Here we used incorporation of trace amounts of recombinant proteins into naturally synchronous macroplasmodia of Physarum polycephalum to examine the function of H3 and H4 tail domains ...

PubMed

58
H4 replication-dependent diacetylation and Hat1 promote S-phase chromatin assembly in vivo
2011-01-15

While specific posttranslational modification patterns within the H3 and H4 tail domains are associated with the S-phase, their actual functions in replication-dependent chromatin assembly have not yet been defined. Here we used incorporation of trace amounts of recombinant proteins into naturally synchronous macroplasmodia of Physarum polycephalum to examine the function of H3 and H4 tail domains ...

PubMed Central

59
Acetylation as a transcriptional control mechanism-HDACs and HATs in pancreatic ductal adenocarcinoma.
2011-06-01

INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors with a dismal prognosis. Although our understanding of the carcinogenesis of the disease increases continuously, no effective conservative therapeutic strategies exist. Therefore, novel targets have to be defined at the experimental level. Histone deacetylases (HDACs), especially the class I isoenzymes HDAC1, ...

PubMed

60
Subunit composition and substrate specificity of a MOF-containing histone acetyltransferase distinct from the male-specific lethal (MSL) complex.
2009-12-14

Human MOF (MYST1), a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs), is the human ortholog of the Drosophila males absent on the first (MOF) protein. MOF is the catalytic subunit of the male-specific lethal (MSL) HAT complex, which plays a key role in dosage compensation in the fly and is ...

PubMed

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61
Subunit Composition and Substrate Specificity of a MOF-containing Histone Acetyltransferase Distinct from the Male-specific Lethal (MSL) Complex*
2010-02-12

Human MOF (MYST1), a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs), is the human ortholog of the Drosophila males absent on the first (MOF) protein. MOF is the catalytic subunit of the male-specific lethal (MSL) HAT complex, which plays a key role in dosage compensation in the fly and is ...

PubMed Central

62
Structural and Functional Conservation of the NuA4 Histone Acetyltransferase Complex from Yeast to Humans
2004-03-01

The NuA4 histone acetyltransferase (HAT) multisubunit complex is responsible for acetylation of histone H4 and H2A N-terminal tails in yeast. Its catalytic component, Esa1, is essential for cell cycle progression, gene-specific regulation and has been implicated in DNA repair. Almost all NuA4 subunits have clear homologues in higher eukaryotes, suggesting ...

PubMed Central

63
Small molecule modulators of histone acetyltransferase p300.
2003-03-06

Histone acetyltransferases (HATs) are a group of enzymes that play a significant role in the regulation of gene expression. These enzymes covalently modify the N-terminal lysine residues of histones by the addition of acetyl groups from acetyl-CoA. Dysfunction of these enzymes is often associated with the manifestation of several diseases, predominantly ...

PubMed

64
Regulation of Insulin Gene Transcription by Multiple Histone Acetyltransferases.
2011-07-20

Glucose-stimulated insulin gene transcription is mainly regulated by a 340-bp promoter region upstream of the transcription start site by beta-cell-enriched transcription factors Pdx-1, MafA, and NeuroD1. Previous studies have shown that histone H4 hyperacetylation is important for acute up-regulation of insulin gene transcription. Until now, only the histone acetyltransferase ...

PubMed

65
Perturbation of mitosis through inhibition of histone acetyltransferases: the key to ochratoxin A toxicity and carcinogenicity?
2011-05-01

Ochratoxin A (OTA) is one of the most potent rodent renal carcinogens studied to date. Although controversial results regarding OTA genotoxicity have been published, it is now widely accepted that OTA is not a mutagenic, DNA-reactive carcinogen. Instead, increasing evidence from both in vivo and in vitro studies suggests that OTA may promote genomic instability and tumorigenesis through ...

PubMed

66
Histone acetyltransferase inhibitor anacardic acid causes changes in global gene expression during in vitro Plasmodium falciparum development.
2008-05-16

To better understand the role of histone lysine acetylation in transcription in Plasmodium falciparum, we sought to attenuate histone acetyltransferase (HAT) activity using anacardic acid (AA). We showed that AA reversibly and noncompetitively inhibited the HAT activity of recombinant PfGCN5. To a lesser extent, AA inhibited the PfGCN5 ...

PubMed

67
Histone Acetyltransferase Inhibitor Anacardic Acid Causes Changes in Global Gene Expression during In Vitro Plasmodium falciparum Development? �
2008-07-16

To better understand the role of histone lysine acetylation in transcription in Plasmodium falciparum, we sought to attenuate histone acetyltransferase (HAT) activity using anacardic acid (AA). We showed that AA reversibly and noncompetitively inhibited the HAT activity of recombinant PfGCN5. To a lesser extent, AA inhibited the PfGCN5 ...

PubMed Central

68
Ex Vivo Expansion of Human Hematopoietic Stem Cells by Garcinol, a Potent Inhibitor of Histone Acetyltransferase
2011-09-12

BackgroundHuman cord blood (hCB) is the main source of hematopoietic stem and progenitor cells (HSCs/PCs) for transplantation. Efforts to overcome relative shortages of HSCs/PCs have led to technologies to expand HSCs/PCs ex vivo. However, methods suitable for clinical practice have yet to be fully established.Methodology/Principal FindingsIn this study, we screened biologically active natural ...

PubMed Central

69
Catalytic activation of histone acetyltransferase Rtt109 by a histone chaperone
2010-11-23

Most histone acetyltransferases (HATs) function as multisubunit complexes in which accessory proteins regulate substrate specificity and catalytic efficiency. Rtt109 is a particularly interesting example of a HAT whose specificity and catalytic activity require association with either of two histone chaperones, Vps75 or Asf1. Here, we ...

PubMed Central

70
Advances in Label-Free Screening Approaches for Studying Histone Acetyltransferases.
2011-09-01

Histone acetyltransferases (HATs) catalyze the transfer of an acetyl group from an acetyl-coenzyme A donor molecule to specific lysine residues within proteins. The acetylation state of proteins, particularly histones, is known to modulate their intermolecular binding properties and control various cellular processes, most notably transcriptional ...

PubMed

71
The role of p300 histone acetyltransferase in UV-induced histone modifications and MMP-1 gene transcription.
2009-03-16

Matrix metalloproteinase (MMP)-1 promotes ultraviolet (UV)-triggered long-term detrimental effects such as cancer formation and premature skin aging. Although histone modifications may play a crucial role in the transcriptional regulation of MMP-1, the relationship between UV-induced histone modification and MMP-1 expression is not completely understood. Here, we identify regulators of histone ...

PubMed

72
The Role of p300 Histone Acetyltransferase in UV-Induced Histone Modifications and MMP-1 Gene Transcription
2009-03-16

Matrix metalloproteinase (MMP)-1 promotes ultraviolet (UV)-triggered long-term detrimental effects such as cancer formation and premature skin aging. Although histone modifications may play a crucial role in the transcriptional regulation of MMP-1, the relationship between UV-induced histone modification and MMP-1 expression is not completely understood. Here, we identify regulators of histone ...

PubMed Central

73
Quercetin Suppresses Cyclooxygenase-2 Expression and Angiogenesis through Inactivation of P300 Signaling
2011-08-08

Quercetin, a polyphenolic bioflavonoid, possesses multiple pharmacological actions including anti-inflammatory and antitumor properties. However, the precise action mechanisms of quercetin remain unclear. Here, we reported the regulatory actions of quercetin on cyclooxygenase-2 (COX-2), an important mediator in inflammation and tumor promotion, and revealed the underlying mechanisms. Quercetin ...

PubMed Central

74
Polyamine-mediated regulation of protein acetylation in murine skin and tumors.
2007-08-01

Overexpression of ornithine decarboxylase (ODC), resulting in increased polyamine metabolism, is a common feature of epithelial tumors. Polyamines play a complex role in promoting tumor development, affecting diverse cellular processes, including gene expression. One way polyamines may affect gene expression is to modulate the multiprotein complexes comprised of transcription factors and ...

PubMed

75
Domains of Tra1 Important for Activator Recruitment and Transcription Coactivator Functions of SAGA and NuA4 Complexes? �
2011-02-13

The Tra1 protein is a direct transcription activator target that is essential for coactivator function of both the SAGA and NuA4 histone acetyltransferase (HAT) complexes. The ?400-kDa Saccharomyces cerevisiae Tra1 polypeptide and its human counterpart TRRAP contain 67 or 68 tandem ?-helical HEAT and TPR protein repeats that extend from the N terminus to ...

PubMed Central

76
Structure of a ternary Naa50p (NAT5/SAN) N{alpha}-terminal acetyltransferase complex reveals the molecular basis for substrate specific acetylation.
2011-09-01

The cotranslational modification of N-terminal acetylation is ubiquitous among eukaryotes and has been reported to have a wide range of biological effects. The human N-terminal acetyltransferase (NAT) Naa50p (NAT5/SAN) acetylates the ?-amino group of proteins containing an N-terminal methionine residue and is essential for proper sister chromatid cohesion and chromosome ...

PubMed

77
The dietary compound curcumin inhibits p300 histone acetyltransferase activity and prevents heart failure in rats
2008-02-21

Hemodynamic overload in the heart can trigger maladaptive hypertrophy of cardiomyocytes. A key signaling event in this process is nuclear acetylation by histone deacetylases and p300, an intrinsic histone acetyltransferase (HAT). It has been previously shown that curcumin, a polyphenol responsible for the yellow color of the spice turmeric, possesses ...

PubMed Central

78
The MYST family histone acetyltransferase regulates gene expression and cell cycle in malaria parasite Plasmodium falciparum.
2010-09-24

Histone lysine acetylation, normally associated with euchromatin and active genes, is regulated by different families of histone acetyltransferases (HATs). A single Plasmodium falciparum MYST (PfMYST) HAT was expressed as a long and a short version in intraerythrocytic stages. Whereas the recombinant PfMYST expressed in prokaryotes and ...

PubMed

79
Small-molecule inhibitors of histone acetyltransferase activity: identification and biological properties.
2006-11-16

Starting from a yeast phenotypic screening performed on 21 compounds, we described the identification of two small molecules (9 and 18) able to significantly reduce the S. cerevisiae cell growth, thus miming the effect of GCN5 deletion mutant. Tested on a GCN5-dependent gene transcription assay, compounds 9 and 18 gave a high reduction of the reporter activity. In S. cerevisiae histone H3 terminal ...

PubMed

80
Paradoxical enhancement of fear extinction memory and synaptic plasticity by inhibition of the histone acetyltransferase p300.
2011-05-18

It is well established that the coordinated regulation of activity-dependent gene expression by the histone acetyltransferase (HAT) family of transcriptional coactivators is crucial for the formation of contextual fear and spatial memory, and for hippocampal synaptic plasticity. However, no studies have examined the role of this epigenetic mechanism within ...

PubMed

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81
Loss of histone acetyltransferase cofactor transformation/transcription domain-associated protein impairs liver regeneration after toxic injury.
2011-02-11

Organ regeneration after toxin challenge or physical injury requires a prompt and balanced cell-proliferative response; a well-orchestrated cascade of gene expression is needed to regulate transcription factors and proteins involved in cell cycle progression and cell proliferation. After liver injury, cell cycle entry and progression of hepatocytes are believed to require concerted efforts of ...

PubMed

82
Histone dynamics and roles of histone acetyltransferases during cold-induced gene regulation in Arabidopsis.
2010-07-27

In Arabidopsis, CBF transcription factors bind to and activate certain cold-regulated (COR) gene promoters during cold acclimation. Consistent with the prevailing model that histone acetylation and nucleosomal depletion correspond with transcriptionally active genes, we now report that H3 acetylation increases and nucleosome occupancy decreases at COR gene promoters upon cold acclimation. ...

PubMed

83
Histone Acetyltransferase Activity of p300 Is Required for Transcriptional Repression by the Promyelocytic Leukemia Zinc Finger Protein
2005-07-01

Histone acetyltransferase (HAT) activities of proteins such as p300, CBP, and P/CAF play important roles in activation of gene expression. We now show that the HAT activity of p300 can also be required for down-regulation of transcription by a DNA binding repressor protein. Promyelocytic leukemia zinc finger (PLZF), originally ...

PubMed Central

84
Grape seed extract regulates androgen receptor-mediated transcription in prostate cancer cells through potent anti-histone acetyltransferase activity.

Histone acetylation, which is regulated by histone acetyltransferases (HATs) and deacetylases, is an epigenetic mechanism that influences eukaryotic transcription. Significant changes in histone acetylation are associated with cancer; therefore, manipulating the acetylation status of key gene targets is likely crucial for effective cancer therapy. Grape ...

PubMed

85
Inhibition of the Acetyltransferases p300 and CBP Reveals a Targetable Function for p300 in the Survival and Invasion Pathways of Prostate Cancer Cell Lines.
2011-06-27

Inhibitors of histone deacetylases have been approved for clinical application in cancer treatment. On the other hand, histone acetyltransferase (HAT) inhibitors have been less extensively investigated for their potential use in cancer therapy. In prostate cancer, the HATs and coactivators p300 and CBP are upregulated and may induce ...

PubMed

86
What Color Hat am I Wearing?
2007-12-12

Three students close their eyes, and the teacher puts a hat on each of their heads (hiding the other two hats)...

NSDL National Science Digital Library

87
ENGINEERING TEST OF JUNGLE HAT WITH HEADNET
1968-06-01

... Title : ENGINEERING TEST OF JUNGLE HAT WITH HEADNET. ... It was concluded that the Jungle Hat with Headnet is suitable for Service Testing. ...

DTIC Science & Technology

88
Black Hats and White Hats: The Effect of Organizational ...
2006-12-01

... Title : Black Hats and White Hats: The Effect of Organizational Culture and Institutional Identity on the Twenty-third Air Force. ...

DTIC Science & Technology

89
p300 mediates androgen-independent transactivation of the androgen receptor by interleukin 6.
2002-10-15

Prostate cancer (PCa) begins as an androgen-dependent tumor that will eventually progress to an androgen-independent stage after androgen ablation. Although little is understood about this transition to androgen independence, the androgen receptor (AR) appears to be involved. The coactivator p300 has been shown to interact with the AR during its androgen-dependent transactivation. We show that ...

PubMed

90
The therapeutic uses of chromatin-modifying agents.
2007-06-01

In contrast to genetic aberrations, epigenetic aberrations can be reversed by the use of histone acetyltransferase (HAT), histone deacetylase (HDAC), SIRT, or histone methyltransferase (HMT) inhibitors. A well-known HDACi, suberoylanilide hydroxamic acid, has been recently approved for the treatment of cutaneous T cell lymphoma, and a number of HDACi are ...

PubMed

91
The RSC Complex Exploits Histone Acetylation to Abrogate the Nucleosomal Barrier to RNA Polymerase II Elongation
2006-11-03

SummaryThe coordinated action of histone acetyltransferases (HATs) and ATP-dependent chromatin remodeling enzymes in promoter-dependent transcription initiation represents a paradigm for how epigenetic information regulates gene expression. However, little is known about how such enzymes function during transcription elongation. Here we investigated the ...

PubMed Central

92
Structural basis for MOF and MSL3 recruitment into the dosage compensation complex by MSL1.
2011-01-09

The male-specific lethal (MSL) complex is required for dosage compensation in Drosophila melanogaster, and analogous complexes exist in mammals. We report structures of binary complexes of mammalian MSL3 and the histone acetyltransferase (HAT) MOF with consecutive segments of MSL1. MSL1 interacts with MSL3 as an extended chain forming an extensive ...

PubMed

93
Protein acetylation sites mediated by Schistosoma mansoni GCN5
2008-05-23

The transcriptional co-activator GCN5, a histone acetyltransferase (HAT), is part of large multimeric complexes that are required for chromatin remodeling and transcription activation. As in other eukaryotes, the DNA from the parasite Schistosome mansoni is organized into nucleosomes and the genome encodes components of chromatin-remodeling complexes. ...

Energy Citations Database

94
Histone/protein deacetylases control Foxp3 expression and the heat shock response of T-regulatory cells.
2011-07-26

Lysine ?-acetylation is a post-translational modification that alters the biochemical properties of many proteins. The reaction is catalyzed by histone/protein acetyltransferases (HATs), and is reversed by histone/protein deacetylases (HDACs). As a result, HATs and HDACs constitute an important, though little recognized, set of ...

PubMed

95
HDACs link the DNA damage response, processing of double-strand breaks and autophagy.
2011-03-01

Protein acetylation is mediated by histone acetyltransferases (HATs) and deacetylases (HDACs), which influence chromatin dynamics, protein turnover and the DNA damage response. ATM and ATR mediate DNA damage checkpoints by sensing double-strand breaks and single-strand-DNA-RFA nucleofilaments, respectively. However, it is unclear how acetylation modulates ...

PubMed

96
Chromatin-related properties of CBP fused to MLL generate a myelodysplastic-like syndrome that evolves into myeloid leukemia
2000-09-01

As a result of the recurring translocation t(11;16) (q23;p13.3), MLL (mixed-lineage leukemia) is fused in frame to CBP (CREB binding protein). This translocation has been documented almost exclusively in cases of acute leukemia or myelodysplasia secondary to therapy with drugs that target DNA topo isomerase�II. The minimal chimeric protein that is produced fuses MLL to the bromodomain, histone ...

PubMed Central

97
Chemogenomic profiling of the cellular effects associated with histone H3 acetylation impairment by a quinoline-derived compound.
2010-08-21

We report the results of a chemogenomic profiling aimed to explore the mode of action of a quinolic analogue of the p300 histone acetyltransferase (HAT) inhibitor anacardic acid, named MC1626. This compound reduced histone H3 acetylation in a dose-dependent manner and the HATs Gcn5 and Rtt109, which specifically target H3 lysines, were ...

PubMed

98
Bromodomains as therapeutic targets.
2011-09-13

Acetylation of lysine residues is a post-translational modification with broad relevance to cellular signalling and disease biology. Enzymes that 'write' (histone acetyltransferases, HATs) and 'erase' (histone deacetylases, HDACs) acetylation sites are an area of extensive research in current drug development, but very few potent inhibitors that modulate ...

PubMed

99
Bromodomains as therapeutic targets
2011-09-01

Acetylation of lysine residues is a post-translational modification with broad relevance to cellular signalling and disease biology. Enzymes that �write� (histone acetyltransferases, HATs) and �erase� (histone deacetylases, HDACs) acetylation sites are an area of extensive research in current drug development, ...

PubMed Central

100
Transgenic Mice Expressing an Inhibitory Truncated Form of p300 Exhibit Long-Term Memory Deficits
2007-09-01

The formation of many forms of long-term memory requires several molecular mechanisms including regulation of gene expression. The mechanisms directing transcription require not only activation of individual transcription factors but also recruitment of transcriptional coactivators. CBP and p300 are transcriptional coactivators that interact with a large number of transcription factors and ...

ERIC Educational Resources Information Center

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101
Negative regulation of transcription coactivator p300 by orphan receptor TR3
2007-12-01

p300 regulates the transcriptional activity of a variety of transcription factors by forming an activation complex and/or promoting histone acetylation. Here, we show a unique characteristic of orphan receptor TR3 in negatively regulating the function of p300. TR3 was found to interact with p300 and inhibited the acetylation of transcription factors induced by p300, resulting in the repression of ...

PubMed Central

102
Histone deacetylase 9 is a negative regulator of adipogenic differentiation.
2011-06-16

Differentiation of preadipocytes into mature adipocytes capable of efficiently storing lipids is an important regulatory mechanism in obesity. Here, we examined the involvement of histone deacetylases (HDACs) and histone acetyltransferases (HATs) in the regulation of adipogenesis. We find that among the various members of the HDAC and ...

PubMed

103
Distinct roles of GCN5/PCAF-mediated H3K9ac and CBP/p300-mediated H3K18/27ac in nuclear receptor transactivation.
2010-12-03

Histone acetyltransferases (HATs) GCN5 and PCAF (GCN5/PCAF) and CBP and p300 (CBP/p300) are transcription co-activators. However, how these two distinct families of HATs regulate gene activation remains unclear. Here, we show deletion of GCN5/PCAF in cells specifically and dramatically reduces acetylation on histone H3K9 (H3K9ac) while ...

PubMed

104
Protein Acetylation Microarray Reveals NuA4 Controls Key Metabolic Target Regulating Gluconeogenesis
2009-03-20

SUMMARYHistone acetyltransferases (HATs) and histone deacetylases (HDACs) conduct many critical functions through nonhistone substrates in metazoans, but only chromatin-associated nonhistone substrates are known in Saccharomyces cerevisiae. Using yeast proteome microarrays, we identified and validated many nonchromatin substrates of the essential ...

PubMed Central

105
Pneumocystis carinii expresses an active Rtt109 histone acetyltransferase.
2010-07-23

Species in the genus Pneumocystis can cause severe pneumonia in immune-compromised hosts. The identification of specific targets present in Pneumocystis species, but lacking in mammalian hosts, is paramount to developing new means to treat this infection. One such potential protein is Rtt109, which is a type of histone acetyltransferase (HAT) required for ...

PubMed

106
Gcn5 and SAGA Regulate Shelterin Protein Turnover and Telomere Maintenance
2009-08-14

SUMMARYHistone acetyltransferases (HATs) play important roles in gene regulation and DNA repair by influencing the accessibility of chromatin to transcription factors and repair proteins. Here we show that deletion of Gcn5 leads to telomere dysfunction in mouse and human cells. Biochemical studies reveal that depletion of Gcn5 or ubiquitin specific ...

PubMed Central

107
Androgen receptor signalling in prostate cancer: the functional consequences of acetylation.
2010-12-28

The androgen receptor (AR) is a ligand activated transcription factor and member of the steroid hormone receptor (SHR) subfamily of nuclear receptors. In the early stages of prostate carcinogenesis, tumour growth is dependent on androgens, and AR directly mediates these effects by modulating gene expression. During transcriptional regulation, the AR recruits numerous cofactors with ...

PubMed

108
Androgen Receptor Signalling in Prostate Cancer: The Functional Consequences of Acetylation
2011-12-28

The androgen receptor (AR) is a ligand activated transcription factor and member of the steroid hormone receptor (SHR) subfamily of nuclear receptors. In the early stages of prostate carcinogenesis, tumour growth is dependent on androgens, and AR directly mediates these effects by modulating gene expression. During transcriptional regulation, the AR recruits numerous cofactors with ...

PubMed Central

109
An Emerging Role for Epigenetic Dysregulation in Arsenic Toxicity and Carcinogenesis
2010-01-01

Competing Interests Declaration: The authors declare they have no competing financial interests. Abbreviations: AHCY, S-adenosylhomocysteine hydrolase; APL, acute promyelocytic leukemias; As, inorganic arsenic; AS3MT, arsenic (+3 oxidation state) methyltransferase; ChIP-on-chip, chromatin immunoprecipitation-on-chip; ChIP-seq, chromatin immunoprecipitation-sequencing; DEFB1, defensin, beta 1; ...

E-print Network

110
The SANT Domain of p400 ATPase Represses Acetyltransferase Activity and Coactivator Function of TIP60 in Basal p21 Gene Expression?
2010-07-01

The TIP60 histone acetyltransferase plays diverse roles in DNA damage responses, DNA double-strand break repair, and transcriptional regulation. TIP60 resides within a multisubunit complex that has been shown to be targeted by transcription factors and to be involved in histone acetylation and transcriptional activation. p400, an SWI2/SNF2-related ATPase that serves as an ...

PubMed Central

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