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Journal articles on the topic 'HAT activity'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Yang, Hongmei, Wei Wei, Michael Menconi, and Per-Olof Hasselgren. "Dexamethasone-induced protein degradation in cultured myotubes is p300/HAT dependent." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 292, no. 1 (January 2007): R337—R334. http://dx.doi.org/10.1152/ajpregu.00230.2006.

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Muscle proteolysis during sepsis and other catabolic conditions is, at least in part, regulated by glucocorticoids. Dexamethasone-treated myotubes are a commonly used in vitro model of muscle wasting. We reported recently that treatment of cultured L6 myotubes with dexamethasone resulted in increased gene and protein expression of the nuclear cofactor p300 but it is not known whether glucocorticoids upregulate p300 histone acetyl transferase (HAT) activity in muscle and whether p300/HAT activity regulates glucocorticoid-induced muscle proteolysis. Here, we found that treatment of cultured L6 myotubes with dexamethasone resulted in increased nuclear p300/HAT activity. Treatment of myotubes with p300 siRNA or transfection of muscle cells with a plasmid expressing p300 that was mutated in its HAT activity domain blocked the dexamethasone-induced increase in protein degradation, supporting a role of p300/HAT in glucocortiocoid-induced muscle proteolysis. In addition to increased HAT activity, treatment of the myotubes with dexamethasone resulted in reduced nuclear expression and activity of histone deacetylases (HDACs) 3 and 6. When myotubes were treated with the HDAC inhibitor trichostatin A, protein degradation increased to the same degree as in dexamethasone-treated myotubes. The results suggest that glucocorticoids increase HAT and decrease HDAC activities in muscle, changes that both favor hyperacetylation. The results also provide evidence that dexamethasone-induced protein degradation in cultured myotubes is, at least in part, regulated by p300/HAT activity.

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2

Smith, Aaron T., Meredith R. Livingston, Antonello Mai, Patrizia Filetici, Sherry F. Queener, and William J. Sullivan. "Quinoline Derivative MC1626, a Putative GCN5 Histone Acetyltransferase (HAT) Inhibitor, Exhibits HAT-Independent Activity against Toxoplasma gondii." Antimicrobial Agents and Chemotherapy 51, no. 3 (December 18, 2006): 1109–11. http://dx.doi.org/10.1128/aac.01256-06.

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ABSTRACT 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 plastid organelle called the apicoplast.

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3

Hansson, Magnus L., Anita E. Popko-Ścibor, Mariana Saint Just Ribeiro, Beverley M. Dancy, Mikael J. Lindberg, Philip A. Cole, and Annika E. Wallberg. "The transcriptional coactivator MAML1 regulates p300 autoacetylation and HAT activity." Nucleic Acids Research 37, no. 9 (March 20, 2009): 2996–3006. http://dx.doi.org/10.1093/nar/gkp163.

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4

Hsu, Chih-Hung, Margaret D. T. Chang, Kang-Yu Tai, Yu-Ting Yang, Pei-Shan Wang, Chi-Ju Chen, Yan-Hsiung Wang, Sheng-Chung Lee, Cheng-Wen Wu, and Li-Jung Juan. "HCMV IE2-mediated inhibition of HAT activity downregulates p53 function." EMBO Journal 23, no. 11 (May 13, 2004): 2269–80. http://dx.doi.org/10.1038/sj.emboj.7600239.

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5

Menzel, Gerhard, Tony Heitkam, Kathrin M. Seibt, Faisal Nouroz, Manuela Müller-Stoermer, John S. Heslop-Harrison, and Thomas Schmidt. "The diversification and activity of hAT transposons in Musa genomes." Chromosome Research 22, no. 4 (November 7, 2014): 559–71. http://dx.doi.org/10.1007/s10577-014-9445-5.

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6

Morris, Brett M., Suzanne L. Hawley, and Leslie Hebb. "Large Starspot Groups on HAT-P-11 in Activity Cycle 1." Research Notes of the AAS 2, no. 1 (February 6, 2018): 26. http://dx.doi.org/10.3847/2515-5172/aaac2e.

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7

Apak, Reşat, Mustafa Özyürek, Kubilay Güçlü, and Esra Çapanoğlu. "Antioxidant Activity/Capacity Measurement. 2. Hydrogen Atom Transfer (HAT)-Based, Mixed-Mode (Electron Transfer (ET)/HAT), and Lipid Peroxidation Assays." Journal of Agricultural and Food Chemistry 64, no. 5 (February 2016): 1028–45. http://dx.doi.org/10.1021/acs.jafc.5b04743.

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8

Wright, Diana, Torsten Wurm, Nicholas Polakowski, Jean-Michel Mesnard, and Isabelle Lemasson. "HBZ inhibits the HAT activity of the cellular coactivators p300 and CBP." Retrovirology 8, Suppl 1 (2011): A150. http://dx.doi.org/10.1186/1742-4690-8-s1-a150.

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9

Sarthi, Jessica, and Felice Elefant. "dTip60 HAT Activity Controls Synaptic Bouton Expansion at the Drosophila Neuromuscular Junction." PLoS ONE 6, no. 10 (October 27, 2011): e26202. http://dx.doi.org/10.1371/journal.pone.0026202.

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10

Yin, Bo-Kun, and Zhao-Qi Wang. "Beyond HAT Adaptor: TRRAP Liaisons with Sp1-Mediated Transcription." International Journal of Molecular Sciences 22, no. 22 (November 18, 2021): 12445. http://dx.doi.org/10.3390/ijms222212445.

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The members of the phosphatidylinositol 3-kinase-related kinase (PIKK) family play vital roles in multiple biological processes, including DNA damage response, metabolism, cell growth, mRNA decay, and transcription. TRRAP, as the only member lacking the enzymatic activity in this family, is an adaptor protein for several histone acetyltransferase (HAT) complexes and a scaffold protein for multiple transcription factors. TRRAP has been demonstrated to regulate various cellular functions in cell cycle progression, cell stemness maintenance and differentiation, as well as neural homeostasis. TRRAP is known to be an important orchestrator of many molecular machineries in gene transcription by modulating the activity of some key transcription factors, including E2F1, c-Myc, p53, and recently, Sp1. This review summarizes the biological and biochemical studies on the action mode of TRRAP together with the transcription factors, focusing on how TRRAP-HAT mediates the transactivation of Sp1-governing biological processes, including neurodegeneration.

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11

Senf, Sarah M., Pooja B. Sandesara, Sarah A. Reed, and Andrew R. Judge. "p300 Acetyltransferase activity differentially regulates the localization and activity of the FOXO homologues in skeletal muscle." American Journal of Physiology-Cell Physiology 300, no. 6 (June 2011): C1490—C1501. http://dx.doi.org/10.1152/ajpcell.00255.2010.

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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 of p300/CREB-binding protein (CBP). Transfection of rat soleus muscle with a dominant-negative p300, which lacks HAT activity and inhibits endogenous p300 HAT activity, increased FOXO reporter activity and induced transcription from the promoter of a bona fide FOXO target gene, atrogin-1. Conversely, increased HAT activity via transfection of either wild-type (WT) p300 or WT CBP repressed FOXO activation in vivo in response to muscle disuse, and in C2C12 cells in response to dexamethasone and acute starvation. Importantly, manipulation of HAT activity differentially regulated the expression of various FOXO target genes. Cotransfection of FOXO1, FOXO3a, or FOXO4 with the p300 constructs further identified p300 HAT activity to also differentially regulate the activity of the FOXO homologues. Markedly, decreased HAT activity strongly increased FOXO3a transcriptional activity, while increased HAT activity repressed FOXO3a activity and prevented its nuclear localization in response to nutrient deprivation. In contrast, p300 increased FOXO1 nuclear localization. In summary, this study provides the first evidence to support the acetyltransferase activities of p300/CBP in regulating FOXO signaling in skeletal muscle and suggests that acetylation may be an important mechanism to differentially regulate the FOXO homologues and dictate which FOXO target genes are activated in response to varying atrophic stimuli.

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12

Morris, Brett M., Suzanne L. Hawley, Leslie Hebb, Charli Sakari, James R. A. Davenport, Howard Isaacson, Andrew W. Howard, Benjamin T. Montet, and Eric Agol. "Chromospheric Activity of HAT-P-11: An Unusually Active Planet-hosting K Star." Astrophysical Journal 848, no. 1 (October 12, 2017): 58. http://dx.doi.org/10.3847/1538-4357/aa8cca.

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13

Sunagawa, Yoichi, Kiyotaka Shimizu, Ayumi Katayama, Masafumi Funamoto, Kana Shimizu, Sari Nurmila, Satoshi Shimizu, et al. "Metformin suppresses phenylephrine-induced hypertrophic responses by inhibiting p300-HAT activity in cardiomyocytes." Journal of Pharmacological Sciences 147, no. 2 (October 2021): 169–75. http://dx.doi.org/10.1016/j.jphs.2021.07.001.

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14

Shimizu, Kana, Yoichi Sunagawa, Masafumi Funamoto, Yasufumi Katanasaka, Hiroyuki Shibata, Hiromichi Wada, Akira Shimatsu, Koji Hasegawa, and Tatsuya Morimoto. "Curcumin Analogue Y-030 Effectively Suppressed Cardiomyocyte Hypertrophy by Inhibiting p300-HAT Activity." Journal of Cardiac Failure 22, no. 9 (September 2016): S207. http://dx.doi.org/10.1016/j.cardfail.2016.07.288.

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15

Deng, Longwen, Dai Wang, Cynthia de la Fuente, Lai Wang, Hong Li, Chee Gun Lee, Robert Donnelly, John D. Wade, Paul Lambert, and Fatah Kashanchi. "Enhancement of the p300 HAT Activity by HIV-1 Tat on Chromatin DNA." Virology 289, no. 2 (October 2001): 312–26. http://dx.doi.org/10.1006/viro.2001.1129.

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16

Husin, Syarief Nur, Primasatria Edastama, and Amirsyah Tambunan. "Digital Marketing Strategy using White Hat SEO Techniques." International Journal of Cyber and IT Service Management 2, no. 2 (September 23, 2022): 171–79. http://dx.doi.org/10.34306/ijcitsm.v2i2.118.

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A journal service system's forum for a publisher platform, or journal publication, that disseminates data about scientific activity, is known as OJS (Open Journal System). By utilizing SEO, websites that already exist may also have their search engine rankings improved. Making it simpler for consumers to locate addresses for scientific journal websites is one technique to use White Hat SEO. This study tries to boost website traffic on sites that host scholarly journals. The White Hat SEO (Search Engine Optimization) strategy was employed in this study. This study was done on a website that had not yet implemented SEO strategies, then used White Hat SEO techniques such optimizing keywords in title tags, content, meta keywords, meta descriptions, and social media sharing. The outcomes of the examination of SEO implementation might make it easier to find websites for scientific journals.

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17

Chen, Chi-Ju, Zhong Deng, Alex Y. Kim, Gerd A. Blobel, and Paul M. Lieberman. "Stimulation of CREB Binding Protein Nucleosomal Histone Acetyltransferase Activity by a Class of Transcriptional Activators." Molecular and Cellular Biology 21, no. 2 (January 15, 2001): 476–87. http://dx.doi.org/10.1128/mcb.21.2.476-487.2001.

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ABSTRACT The transcriptional coactivator CREB binding protein (CBP) possesses intrinsic histone acetyltransferase (HAT) activity that is important for gene regulation. CBP binds to and cooperates with numerous nuclear factors to stimulate transcription, but it is unclear if these factors modulate CBP HAT activity. Our previous work showed that CBP interacts with the Epstein-Barr virus-encoded basic region zipper (b-zip) protein, Zta, and augments its transcriptional activity. Here we report that Zta strongly enhances CBP-mediated acetylation of nucleosomal histones. Zta stimulated the HAT activity of CBP that had been partially purified or immunoprecipitated from mammalian cells as well as from affinity-purified, baculovirus expressed CBP. Stimulation of nucleosome acetylation required the CBP HAT domain, the Zta DNA binding and transcription activation domain, and nucleosomal DNA. In addition to Zta, we found that two other b-zip proteins, NF-E2 and C/EBPα, strongly stimulated nucleosomal HAT activity. In contrast, several CBP-binding proteins, including phospho-CREB, JUN/FOS, GATA-1, Pit-1, and EKLF, failed to stimulate HAT activity. These results demonstrate that a subset of transcriptional activators enhance the nucleosome-directed HAT activity of CBP and suggest that nuclear factors may regulate transcription by altering substrate recognition and/or the enzymatic activity of chromatin modifying coactivators.

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18

Li, Fen, Jixian Ma, Yu Ma, Yanyan Hu, Shujuan Tian, Richard E. White, and Guichun Han. "hElp3 Directly Modulates the Expression of HSP70 Gene in HeLa Cells via HAT Activity." PLoS ONE 6, no. 12 (December 21, 2011): e29303. http://dx.doi.org/10.1371/journal.pone.0029303.

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19

Kawasaki, H., K. Taira, and K. Yokoyama. "Histone acetyltransferase (HAT) activity of ATF-2 is necessary for the CRE-dependent transcription." Nucleic Acids Symposium Series 44, no. 1 (October 1, 2000): 259–60. http://dx.doi.org/10.1093/nass/44.1.259.

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20

Victor, Martin, Yanxia Bei, Frédérique Gay, Dominica Calvo, Craig Mello, and Yang Shi. "HAT activity is essential for CBP‐1‐dependent transcription and differentiation in Caenorhabditis elegans." EMBO reports 3, no. 1 (January 2002): 50–55. http://dx.doi.org/10.1093/embo-reports/kvf006.

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21

Katagiri, Takahiro, Yoichi Sunagawa, Tatsuya Maekawa, Masafumi Funamoto, Satoshi Shimizu, Kana Shimizu, Yasufumi Katanasaka, et al. "Ecklonia stolonifera Okamura Extract Suppresses Myocardial Infarction-Induced Left Ventricular Systolic Dysfunction by Inhibiting p300-HAT Activity." Nutrients 14, no. 3 (January 28, 2022): 580. http://dx.doi.org/10.3390/nu14030580.

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Ecklonia stolonifera Okamura extract (ESE) has been reported to have various bioactive effects, but its effects on cardiovascular disease have not yet been investigated. First, primary neonatal rat cultured cardiomyocytes were treated with ESE and stimulated with phenylephrine (PE) for 48 h. ESE (1000 µg/mL) significantly suppressed PE-induced cardiomyocyte hypertrophy, hypertrophy-related gene transcription, and the acetylation of histone H3K9. An in vitro p300-HAT assay indicated that ESE directly inhibited p300-HAT activity. Next, one week after myocardial infarction (MI) surgery, rats (left ventricular fractional shortening (LVFS) < 40%) were randomly assigned to three groups: vehicle (saline, n = 9), ESE (0.3 g/kg, n = 10), or ESE (1 g/kg, n = 10). Daily oral administration was carried out for 8 weeks. After treatment, LVFS was significantly higher in the ESE (1 g/kg) group than in the vehicle group. The ESE treatments also significantly suppressed MI-induced increases in myocardial cell diameter, perivascular fibrosis, hypertrophy- and fibrosis-related gene transcription, and the acetylation of histone H3K9. These results suggest that ESE suppressed both hypertrophic responses in cardiomyocytes and the development of heart failure in rats by inhibiting p300-HAT activity. Thus, this dietary extract is a potential novel therapeutic strategy for heart failure in humans.

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22

Michael, Bindhu, Amrithraj M. Nair, Antara Datta, Hajime Hiraragi, Lee Ratner, and Michael D. Lairmore. "Histone acetyltransferase (HAT) activity of p300 modulates human T lymphotropic virus type 1 p30II-mediated repression of LTR transcriptional activity." Virology 354, no. 2 (October 2006): 225–39. http://dx.doi.org/10.1016/j.virol.2006.07.002.

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23

Peserico, Alessia, and Cristiano Simone. "Physical and Functional HAT/HDAC Interplay Regulates Protein Acetylation Balance." Journal of Biomedicine and Biotechnology 2011 (2011): 1–10. http://dx.doi.org/10.1155/2011/371832.

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The balance between protein acetylation and deacetylation controls several physiological and pathological cellular processes, and the enzymes involved in the maintenance of this equilibrium—acetyltransferases (HATs) and deacetylases (HDACs)—have been widely studied. Presently, the evidences obtained in this field suggest that the dynamic acetylation equilibrium is mostly maintained through the physical and functional interplay between HAT and HDAC activities. This model overcomes the classical vision in which the epigenetic marks of acetylation have only an activating function whereas deacetylation marks have a repressing activity. Given the existence of several players involved in the preservation of this equilibrium, the identification of these complex networks of interacting proteins will likely foster our understanding of how cells regulate intracellular processes and respond to the extracellular environment and will offer the rationale for new therapeutic approaches based on epigenetic drugs in human diseases.

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24

Shin, Sung Hwa. "Phosphorylation of Tip60 Tyrosine 327 by Abl Kinase Inhibits HAT Activity through Association with FE65." Open Biochemistry Journal 7, no. 1 (August 22, 2013): 66–72. http://dx.doi.org/10.2174/1874091x01307010066.

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25

Shin, Sung Hwa, and Sang Sun Kang. "Phosphorylation of Tip60 Tyrosine 327 by Abl Kinase Inhibits HAT Activity through Association with FE65." Open Biochemistry Journal 7 (August 22, 2013): 66–72. http://dx.doi.org/10.2174/1874091x20130621002.

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26

Hwa Shin, Sung, and Sang Sun Kang. "Phosphorylation of Tip60 Tyrosine 327 by Abl Kinase Inhibits HAT Activity through Association with FE65." Open Biochemistry Journal 7, no. 1 (August 22, 2013): 66–72. http://dx.doi.org/10.2174/1874091x20130622002.

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27

Ganai, Shabir Ahmad, Shahid Banday, Zeenat Farooq, and Mohammad Altaf. "Modulating epigenetic HAT activity for reinstating acetylation homeostasis: A promising therapeutic strategy for neurological disorders." Pharmacology & Therapeutics 166 (October 2016): 106–22. http://dx.doi.org/10.1016/j.pharmthera.2016.07.001.

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28

LUNARDI, RAFAELA F., MARIANE WOHLENBERG, NIARA MEDEIROS, FABIANE AGOSTINI, CLÁUDIA FUNCHAL, and CAROLINE DANI. "In vitro antioxidant capacity of tea of Echinodorus grandiforus, “leather hat,” in Wistar rat liver." Anais da Academia Brasileira de Ciências 86, no. 3 (July 22, 2014): 1451–62. http://dx.doi.org/10.1590/0001-3765201420130507.

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Oxidative stress has been considered as one of the factors responsible for hepatic diseases, which sometimes require new ways of treatment. The present study aimed to evaluate the in vitro antioxidant capacity of the tea of Echinodorus grandiforus (“leather hat” plant) in rat liver. Different preparations of tea were evaluated for phenolic composition, antioxidant activity by DPPH assay and ability to inhibit lipid peroxidation induced by copper sulfate. The antioxidant activity was assessed in liver tissue treated with sodium azide in the presence or absence of tea by assays for lipid peroxidation (TBARS), protein oxidation (carbonyl) and the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). The results show that different preparations of tea are important sources of polyphenols and contain theobromine, catechin and vitexin. Furthermore, the results indicate that this tea exhibits an antioxidant activity by its ability to scavenge DPPH radical. Different preparations of tea prevented damage to lipids and proteins induced by sodium azide, as well as assisting in restoring CAT and SOD activities. Thus, it can be seen that E. grandiforus tea had antioxidant activity in serum and liver being able to prevent oxidative damages generated by sodium azide.

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29

Sharp, Paul, Joan L. Bottorff, John L. Oliffe, Kate Hunt, and Cristina M. Caperchione. "Process evaluation of HAT TRICK: feasibility, acceptability and opportunities for programme refinement." Health Education Research 35, no. 6 (October 25, 2020): 605–17. http://dx.doi.org/10.1093/her/cyaa029.

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Abstract Preventive lifestyle interventions are needed to address challenges in engaging men in conventional health programmes. This process evaluation examined the feasibility and acceptability of HAT TRICK, a gender-sensitized programme targeting physical activity, healthy eating and social connectedness. A mixed-methods approach was utilized to examine the effectiveness of recruitment and selection processes, facilitators’ experiences and challenges and participant experiences with the programme. Evaluation measures included participant flow data and baseline assessments, facilitator debriefs, a post-intervention process evaluation questionnaire and telephone interviews with a subsample of participants. Participants (n = 62) were overweight (body mass index [BMI] > 25 kg m−2) and inactive (<150 min of moderate to vigorous physical activity [MVPA] per week) men with a mean age 51 ± 10.1 years. Participants reported high levels of satisfaction, acceptability and engagement with the intervention programme, content and resources. Facilitators noted the importance of creating a friendly, non-judgemental environment and observed that intervention content was best received when delivered in an interactive and engaging manner. Future programme refinements should consider strategies for strengthening social support, as well as opportunities for leveraging participants’ interest in other health-related issues (e.g. mental health). Findings yield valuable information about the implementation of gender-sensitized interventions for men and demonstrate the importance of male-specific engagement strategies for reaching and engaging overweight, inactive men.

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30

Námesztovszki, Zsolt, Dorottya Balázs P., Cintia Kovács, Lenke Major, and Dijana Karuović. "Hogyan alakul (hat) a tanulói aktivitás egy MOOC során?" Információs Társadalom 16, no. 4 (May 11, 2017): 40. http://dx.doi.org/10.22503/inftars.xvi.2016.4.3.

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Manapság egyre több szó esik az időtől és helytől független tanulásról, amely elektronikus eszközök segítségével valósul meg. Ezen eszközök szervezett és összefogott megjelenítését biztosítják a MOOC (Massive Open Online Course) típusú kurzusok. Ezek a kurzusok egyre nagyobb népszerűségnek örvendenek az oktatók és a tanulók körében is, és egyre több ilyen struktúrájú képzés jelenik meg. Az utóbbi években magyar nyelvű képzések is egyre gyakrabban érhetők el, azonban ezek működése (az empirikus adatok tükrében) már kevésbé ismert. Ezt a kört bővíti ez a tanulmány, amely a tanulói aktivitás intenzitását vizsgálja a videómegtekintések, a fórumaktivitások és a tesztek kitöltésének ideje alapján három, saját készítésű MOOC felületén. --- Tracing learners' activity patterns in 3 MOOC trainings Nowadays, more and more researchers and teachers are talking about e-learning, which makes education independent of time and place. The MOOC (Massive Open Online Course) provides the organized and coordinated look of these e-learning tools. These courses are becoming more and more popular among instructors and students alike, and there are a number of these sorts of structured courses. In recent years there have also been a great number of courses available in Hungarian too, but their working process is less well-known (in light of empirical data). This study examines the intensity of the student activities during the video-material, the forum activities and the time of completion of the tests, on the basis of three self-made MOOCs.

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31

Funamoto, Masafumi, Yoichi Sunagawa, Mai Gempei, Kana Shimizu, Yasufumi Katanasaka, Satoshi Shimizu, Toshihide Hamabe-Horiike, et al. "Pyrazole-Curcumin Suppresses Cardiomyocyte Hypertrophy by Disrupting the CDK9/CyclinT1 Complex." Pharmaceutics 14, no. 6 (June 15, 2022): 1269. http://dx.doi.org/10.3390/pharmaceutics14061269.

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The intrinsic histone acetyltransferase (HAT), p300, has an important role in the development and progression of heart failure. Curcumin (CUR), a natural p300-specific HAT inhibitor, suppresses hypertrophic responses and prevents deterioration of left-ventricular systolic function in heart-failure models. However, few structure–activity relationship studies on cardiomyocyte hypertrophy using CUR have been conducted. To evaluate if prenylated pyrazolo curcumin (PPC) and curcumin pyrazole (PyrC) can suppress cardiomyocyte hypertrophy, cultured cardiomyocytes were treated with CUR, PPC, or PyrC and then stimulated with phenylephrine (PE). PE-induced cardiomyocyte hypertrophy was inhibited by PyrC but not PPC at a lower concentration than CUR. Western blotting showed that PyrC suppressed PE-induced histone acetylation. However, an in vitro HAT assay showed that PyrC did not directly inhibit p300-HAT activity. As Cdk9 phosphorylates both RNA polymerase II and p300 and increases p300-HAT activity, the effects of CUR and PyrC on the kinase activity of Cdk9 were examined. Phosphorylation of p300 by Cdk9 was suppressed by PyrC. Immunoprecipitation-WB showed that PyrC inhibits Cdk9 binding to CyclinT1 in cultured cardiomyocytes. PyrC may prevent cardiomyocyte hypertrophic responses by indirectly suppressing both p300-HAT activity and RNA polymerase II transcription elongation activity via inhibition of Cdk9 kinase activity.

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32

Chen, Siyu, Yong Li, Yufang Hu, Yitao Han, Yan Huang, Zhou Nie, and Shouzhuo Yao. "Nucleic acid-mimicking coordination polymer for label-free fluorescent activity assay of histone acetyltransferases." Chemical Communications 51, no. 21 (2015): 4469–72. http://dx.doi.org/10.1039/c5cc00067j.

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A novel and label-free fluorescence assay for histone acetyltransferase (HAT) activity was established via in situ generation of a nucleic acid-mimicking CoA–Au(i) coordination polymer (CP). Moreover, the potency of this assay for HAT-targeted drug discovery was proved by screening HAT inhibitors.

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33

Keck, Kristin M., and Lucy F. Pemberton. "Interaction with the Histone Chaperone Vps75 Promotes Nuclear Localization and HAT Activity of Rtt109 In Vivo." Traffic 12, no. 7 (May 5, 2011): 826–39. http://dx.doi.org/10.1111/j.1600-0854.2011.01202.x.

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34

Sunagawa, Yoichi, Masafumi Funamoto, Shogo Sono, Kana Shimizu, Satoshi Shimizu, Mai Genpei, Yusuke Miyazaki, et al. "Curcumin and its demethoxy derivatives possess p300 HAT inhibitory activity and suppress hypertrophic responses in cardiomyocytes." Journal of Pharmacological Sciences 136, no. 4 (April 2018): 212–17. http://dx.doi.org/10.1016/j.jphs.2017.12.013.

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35

Jiang, Hua, Hanxin Lu, R. Louis Schiltz, Cynthia A. Pise-Masison, Vasily V. Ogryzko, Yoshihiro Nakatani, and John N. Brady. "PCAF Interacts with Tax and Stimulates Tax Transactivation in a Histone Acetyltransferase-Independent Manner." Molecular and Cellular Biology 19, no. 12 (December 1, 1999): 8136–45. http://dx.doi.org/10.1128/mcb.19.12.8136.

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ABSTRACT Recent studies have shown that the p300/CREB binding protein (CBP)-associated factor (PCAF) is involved in transcriptional activation. PCAF activity has been shown strongly associated with histone acetyltransferase (HAT) activity. In this report, we present evidence for a HAT-independent transcription function that is activated in the presence of the human T-cell leukemia virus type 1 (HTLV-1) Tax protein. In vitro and in vivo GST-Tax pull-down and coimmunoprecipitation experiments demonstrate that there is a direct interaction between Tax and PCAF, independent of p300/CBP. PCAF can be recruited to the HTLV-1 Tax responsive element in the presence of Tax, and PCAF cooperates with Tax in vivo to activate transcription from the HTLV-1 LTR over 10-fold. Point mutations at Tax amino acid 318 (TaxS318A) or 319 to 320 (Tax M47), which have decreased or no activity on the HTLV-1 promoter, are defective for PCAF binding. Strikingly, the ability of PCAF to stimulate Tax transactivation is not solely dependent on the PCAF HAT domain. Two independent PCAF HAT mutants, which knock out acetyltransferase enzyme activity, activate Tax transactivation to approximately the same level as wild-type PCAF. In contrast, p300 stimulation of Tax transactivation is HAT dependent. These studies provide experimental evidence that PCAF contains a coactivator transcription function independent of the HAT activity on the viral long terminal repeat.

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Hu, Yufang, Siyu Chen, Yitao Han, Hongjun Chen, Qin Wang, Zhou Nie, Yan Huang, and Shouzhuo Yao. "Unique electrocatalytic activity of a nucleic acid-mimicking coordination polymer for the sensitive detection of coenzyme A and histone acetyltransferase activity." Chemical Communications 51, no. 99 (2015): 17611–14. http://dx.doi.org/10.1039/c5cc06593c.

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Perez-Campo, Flor M., Julian Borrow, Valerie Kouskoff, and Georges Lacaud. "The histone acetyl transferase activity of monocytic leukemia zinc finger is critical for the proliferation of hematopoietic precursors." Blood 113, no. 20 (May 14, 2009): 4866–74. http://dx.doi.org/10.1182/blood-2008-04-152017.

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The monocytic leukemia zinc finger (MOZ) gene encodes a large multidomain protein that contains, besides other domains, 2 coactivation domains for the transcription factor Runx1/acute myeloid leukemia 1 and a histone acetyl transferase (HAT) catalytic domain. Recent studies have demonstrated the critical requirement for the complete MOZ protein in hematopoietic stem cell development and maintenance. However, the specific function of the HAT activity of MOZ remains unknown, as it has been shown that MOZ HAT activity is not required either for its role as Runx1 coactivator or for the leukemic transformation induced by MOZ transcriptional intermediary factor 2 (TIF2). To assess the specific requirement for this HAT activity during hematopoietic development, we have generated embryonic stem cells and mouse lines carrying a point mutation that renders the protein catalytically inactive. We report in this study that mice exclusively lacking the HAT activity of MOZ exhibit significant defects in the number of hematopoietic stem cells and hematopoietic committed precursors as well as a defect in B-cell development. Furthermore, we demonstrate that the failure to maintain a normal number of hematopoietic precursors is caused by the inability of HAT−/− cells to expand. These results indicate a specific role of MOZ-driven acetylation in controlling a desirable balance between proliferation and differentiation during hematopoiesis.

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Shen, Wei-fang, Keerthi Krishnan, H. J. Lawrence, and Corey Largman. "The HOX Homeodomain Proteins Block CBP Histone Acetyltransferase Activity." Molecular and Cellular Biology 21, no. 21 (November 1, 2001): 7509–22. http://dx.doi.org/10.1128/mcb.21.21.7509-7522.2001.

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ABSTRACT Despite the identification of PBC proteins as cofactors that provide DNA affinity and binding specificity for the HOX homeodomain proteins, HOX proteins do not demonstrate robust activity in transient-transcription assays and few authentic downstream targets have been identified for these putative transcription factors. During a search for additional cofactors, we established that each of the 14 HOX proteins tested, from 11 separate paralog groups, binds to CBP or p300. All six isolated homeodomain fragments tested bind to CBP, suggesting that the homeodomain is a common site of interaction. Surprisingly, CBP-p300 does not form DNA binding complexes with the HOX proteins but instead prevents their binding to DNA. The HOX proteins are not substrates for CBP histone acetyltransferase (HAT) but instead inhibit the activity of CBP in both in vitro and in vivo systems. These mutually inhibitory interactions are reflected by the inability of CBP to potentiate the low levels of gene activation induced by HOX proteins in a range of reporter assays. We propose two models for HOX protein function: (i) HOX proteins may function without CBP HAT to regulate transcription as cooperative DNA binding molecules with PBX, MEIS, or other cofactors, and (ii) the HOX proteins may inhibit CBP HAT activity and thus function as repressors of gene transcription.

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Genpei, Mai, Yoichi Sunagawa, Masafumi Funamoto, Kana Shimizu, Yusuke Miyazaki, Yasufumi Katanasaka, Nobuaki Takahashi, et al. "The Inhibitory Effects of Crucumin Glucuronide on p300-HAT Activity and Hypertrophic Phenylephrine- Induced Responses in Cardiomyocytes." European Cardiology Review 12, no. 2 (2017): 107. http://dx.doi.org/10.15420/ecr.2017:23:16.

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Clarke, Astrid S., Eva Samal, and Lorraine Pillus. "Distinct Roles for the Essential MYST Family HAT Esa1p in Transcriptional Silencing." Molecular Biology of the Cell 17, no. 4 (April 2006): 1744–57. http://dx.doi.org/10.1091/mbc.e05-07-0613.

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Among acetyltransferases, the MYST family enzyme Esa1p is distinguished for its essential function and contribution to transcriptional activation and DNA double-stranded break repair. Here we report that Esa1p also plays a key role in silencing RNA polymerase II (Pol II)-transcribed genes at telomeres and within the ribosomal DNA (rDNA) of the nucleolus. These effects are mediated through Esa1p's HAT activity and correlate with changes within the nucleolus. Esa1p is enriched within the rDNA, as is the NAD-dependent protein deacetylase Sir2p, and the acetylation levels of key Esa1p histone targets are reduced in the rDNA in esa1 mutants. Although mutants of both ESA1 and SIR2 have enhanced rates of rDNA recombination, esa1 effects are more modest yet result in distinct structural changes of rDNA chromatin. Surprisingly, increased expression of ESA1 can bypass the requirement for Sir2p in rDNA silencing, suggesting that these two enzymes with seemingly opposing activities both contribute to achieve optimal nucleolar chromatin structure and function.

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Li, Yan, Mi Zhou, Xiuying Lv, Lina Song, Di Zhang, Yan He, Mian Wang, et al. "Reduced Activity of HDAC3 and Increased Acetylation of Histones H3 in Peripheral Blood Mononuclear Cells of Patients with Rheumatoid Arthritis." Journal of Immunology Research 2018 (October 3, 2018): 1–10. http://dx.doi.org/10.1155/2018/7313515.

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Aberrant histone acetylation and deacetylation are increasingly thought to play important roles in the pathogenesis of rheumatoid arthritis (RA). However, limited data from studies about the activity of histone deacetylases (HDACs) and histone acetyltransferase (HAT) in RA are controversial. Those conflicting results may be caused by sample size, medication, and age- and sex-matched controls. The aim of this study is to investigate the expression and activity of class I HDACs (1–3.8) and their effects on histone acetylation in peripheral blood mononuclear cells (PBMCs) from RA patients. The expression of class I HDACs in PBMCs from RA patients was decreased in both mRNA and protein levels in comparison with HCs. The nuclear HAT activities were dramatically increased. Further, we found HDAC3 activity to be the most significantly reduced in overall reduction of HDACs in the RA group. The extent of total histone H3, but not H4, acetylation in PBMCs from RA patients was increased compared to that in healthy controls (HCs) (p<0.01). In RA PBMCs, the activity and expression of class I HDACs are decreased, which is accompanied with enhanced HAT activity. An altered balance between HDAC and HAT activity was found in RA PBMCs.

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Hoffmann, Anke, Thomas Barz, and Dietmar Spengler. "Multitasking C2H2 Zinc Fingers Link Zac DNA Binding to Coordinated Regulation of p300-Histone Acetyltransferase Activity." Molecular and Cellular Biology 26, no. 14 (July 15, 2006): 5544–57. http://dx.doi.org/10.1128/mcb.02270-05.

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ABSTRACT 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 transactivation in a strictly HAT-dependent manner. Whereas the classic recruitment model proposes that coactivation simply depends on the capacity of the activator to recruit the coactivator, we demonstrate that coordinated binding of Zac zinc fingers and C terminus to p300 regulates HAT function by increasing histone and acetyl coenzyme A affinities and catalytic activity. This concerted regulation of HAT function is mediated via the KIX and CH3 domains of p300 in an interdependent manner. Interestingly, Zac zinc fingers 6 and 7 simultaneously play key roles in DNA binding and p300 regulation. Our findings demonstrate, for the first time, that C2H2 zinc fingers can link DNA binding to HAT signaling and suggest a dynamic role for DNA-binding proteins in the enzymatic control of transcription.

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FARMANZADEH, DAVOOD, and MEYSAM NAJAFI. "ANTIOXIDANT ACTIVITY OF AMINOTHIAZOL HYDROXYCOUMARIN DERIVATIVES." Journal of Theoretical and Computational Chemistry 12, no. 06 (September 2013): 1350058. http://dx.doi.org/10.1142/s0219633613500582.

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In this work, the antioxidant properties of the series of 10 aminothiazol hydroxyl coumarin derivatives have been investigated with DFT/B3LYP method. For these antioxidants all reaction enthalpies related to HAT, SPLET, SET-PT mechanisms were calculated in the gas phase and polar solvents. Based on calculated reaction enthalpies (BDE, IP and PA values) the derivations 2, 3 and 4 have the highest antioxidant activity among the studied compounds. Calculated results show that derivations 7, 5 and 6 have the lowest antioxidant activity. The observed theoretical trends for antioxidant activities of studied compounds were similar to trends of previous experimental studies that OH50, TAC50, IC50, CE50 values have been used as a benchmark for measuring the antioxidant properties of these compounds. These results can be useful in synthesis of novel aminothiazol hydroxycoumarin derivatives with high antioxidant activity. Calculated results show that BDE, PA and IP values of studied derivations have linear dependence with structure parameters such as R( O – H ), q( O ) and E HOMO . These observed linear dependences can be useful in synthesis of novel aminothiazol hydroxyl coumarin derivatives with high antioxidant activity. For studied compounds, results indicated that the SPLET and HAT mechanisms represent the thermodynamically preferred mechanism both, in solvent and the gas phase.

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Moon, Phil-Dong, Hyun-Na Koo, Hyun-Ja Jeong, Ho-Jeong Na, Su-Jin Kim, Gab-Soo Hwang, Na-Ra Han, Seung-Heon Hong, Hyung-Min Kim, and Jae-Young Um. "Haeamtang Induces Apoptosis of Colon Cancer HT-29 Cells through Activation of Caspase-3." American Journal of Chinese Medicine 35, no. 05 (January 2007): 897–909. http://dx.doi.org/10.1142/s0192415x07005363.

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The effect of Haeamtang (HAT) on the colon cancer HT-29 cells was investigated in this study. A water extract of HAT significantly decreased the number of HT-29 cells in a dose-and time-dependent manner as determined by a MTT assay. Flow cytometry results revealed a dose- and time-dependent increase of dead cells in HT-29 cells treated with HAT extract. The anticancer activity of the H AT extract is attributed to apoptosis induced in HT-29 cells, which was demonstrated by increased caspase-3 activity and poly-ADP-ribose polymerase fragmentation. A selective caspase inhibitor, z-VAD-fmk, inhibited the HAT-induced cell death. Taken together, these results demonstrate that HAT extract induces apoptosis in HT-29 cells.

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Ohba, Reiko, David J. Steger, James E. Brownell, Craig A. Mizzen, Richard G. Cook, Jacques Côté, Jerry L. Workman, and C. David Allis. "A Novel H2A/H4 Nucleosomal Histone Acetyltransferase in Tetrahymena thermophila." Molecular and Cellular Biology 19, no. 3 (March 1, 1999): 2061–68. http://dx.doi.org/10.1128/mcb.19.3.2061.

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ABSTRACT Recently, we reported the identification of a 55-kDa polypeptide (p55) from Tetrahymena macronuclei as a catalytic subunit of a transcription-associated histone acetyltransferase (HAT A). Extensive homology between p55 and Gcn5p, a component of the SAGA and ADA transcriptional coactivator complexes in budding yeast, suggests an immediate link between the regulation of chromatin structure and transcriptional output. Here we report the characterization of a second transcription-associated HAT activity from Tetrahymenamacronuclei. This novel activity is distinct from complexes containing p55 and putative ciliate SAGA and ADA components and shares several characteristics with NuA4 (for nucleosomal H2A/H4), a 1.8-MDa, Gcn5p-independent HAT complex recently described in yeast. A key feature of both the NuA4 and Tetrahymena activities is their acetylation site specificity for lysines 5, 8, 12, and 16 of H4 and lysines 5 and 9 of H2A in nucleosomal substrates, patterns that are distinct from those of known Gcn5p family members. Moreover, like NuA4, the Tetrahymena activity is capable of activating transcription from nucleosomal templates in vitro in an acetyl coenzyme A-dependent fashion. Unlike NuA4, however, sucrose gradient analyses of the ciliate enzyme, following sequential denaturation and renaturation, estimate the molecular size of the catalytically active subunit to be ∼80 kDa, consistent with the notion that a single polypeptide or a stable subcomplex is sufficient for this H2A/H4 nucleosomal HAT activity. Together, these data document the importance of this novel HAT activity for transcriptional activation from chromatin templates and suggest that a second catalytic HAT subunit, in addition to p55/Gcn5p, is conserved between yeast and Tetrahymena.

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Park, Sangho, Robyn L. Stanfield, Maria A. Martinez-Yamout, H. Jane Dyson, Ian A. Wilson, and Peter E. Wright. "Role of the CBP catalytic core in intramolecular SUMOylation and control of histone H3 acetylation." Proceedings of the National Academy of Sciences 114, no. 27 (June 19, 2017): E5335—E5342. http://dx.doi.org/10.1073/pnas.1703105114.

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The histone acetyl transferases CREB-binding protein (CBP) and its paralog p300 play a critical role in numerous cellular processes. Dysregulation of their catalytic activity is associated with several human diseases. Previous work has elucidated the regulatory mechanisms of p300 acetyltransferase activity, but it is not known whether CBP activity is controlled similarly. Here, we present the crystal structure of the CBP catalytic core encompassing the bromodomain (BRD), CH2 (comprising PHD and RING), HAT, and ZZ domains at 2.4-Å resolution. The BRD, PHD, and HAT domains form an integral structural unit to which the RING and ZZ domains are flexibly attached. The structure of the apo-CBP HAT domain is similar to that of acyl-CoA–bound p300 HAT complexes and shows that the acetyl-CoA binding site is stably formed in the absence of cofactor. The BRD, PHD, and ZZ domains interact with small ubiquitin-like modifier 1 (SUMO-1) and Ubc9, and function as an intramolecular E3 ligase for SUMOylation of the cell cycle regulatory domain 1 (CRD1) of CBP, which is located adjacent to the BRD. In vitro HAT assays suggest that the RING domain, the autoregulatory loop (AL) within the HAT domain, and the ZZ domain do not directly influence catalytic activity, whereas the BRD is essential for histone H3 acetylation in nucleosomal substrates. Several lysine residues in the intrinsically disordered AL are autoacetylated by the HAT domain. Upon autoacetylation, acetyl-K1596 (Ac-K1596) binds intramolecularly to the BRD, competing with histones for binding to the BRD and acting as a negative regulator that inhibits histone H3 acetylation.

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Churangsarit, Saowaphan, and Virasakdi Chongsuvivatwong. "Spatial and Social Factors Associated With Transportation and Recreational Physical Activity Among Adults in Hat Yai City, Songkhla, Thailand." Journal of Physical Activity and Health 8, no. 6 (August 2011): 758–65. http://dx.doi.org/10.1123/jpah.8.6.758.

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Background:Transportation physical activity (TPA) and recreational physical activity (RPA) in an urban area can be sources of physical activity (PA) in addition to working. This study was conducted in Hat Yai City Municipality, the fourth most populous city in Thailand, to describe the magnitude of these physical activities and identify their associated factors.Methods:369 adults were selected from a random sampling of registered households. Based on the Global Physical Activity Questionnaire (GPAQ), subjects were interviewed on their modes of TPA and RPA during the past week. Hurdle regression was used to examine predictors for having PA separately from predictor of intensity of PA among the active. Metabolic equivalent (MET) of TPA and RPA were computed.Results:Prevalence of not having TPA and RPA were 71.3% and 45.8%, respectively. TPA and RPA contributed 1.5% and 9.2% of total PA. Active commuters were more common in females 40 or more years old, less sedentary persons, and those living near shopping places. Persons having RPA were more likely to be less sedentary, whereas the intensity of RPA was higher among single persons and males.Conclusion:TPA and RPA in this study area were uncommon. Further strategies are needed to improve the situation, especially among sedentary persons.

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Bu, Ping, Yvonne A. Evrard, Guillermina Lozano, and Sharon Y. R. Dent. "Loss of Gcn5 Acetyltransferase Activity Leads to Neural Tube Closure Defects and Exencephaly in Mouse Embryos." Molecular and Cellular Biology 27, no. 9 (February 26, 2007): 3405–16. http://dx.doi.org/10.1128/mcb.00066-07.

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ABSTRACT Gcn5 was the first transcription-related histone acetyltransferase (HAT) to be identified. However, the functions of this enzyme in mammalian cells remain poorly defined. Deletion of Gcn5 in mice leads to early embryonic lethality with increased apoptosis in mesodermal lineages. Here we show that deletion of p53 allows Gcn5 −/− embryos to survive longer, but Gcn5 −/− p53 −/− embryos still die in midgestation. Interestingly, embryos homozygous for point mutations in the Gcn5 catalytic domain survive significantly longer than Gcn5 −/− or Gcn5 −/− p53 −/− mice. In contrast to Gcn5 −/− embryos, Gcn5 hat/hat embryos do not exhibit increased apoptosis but do exhibit severe cranial neural tube closure defects and exencephaly. Together, our results indicate that Gcn5 has important, HAT-independent functions in early development and that Gcn5 acetyltransferase activity is required for cranial neural tube closure in the mouse.

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Cui, Long, Jun Miao, Tetsuya Furuya, Qi Fan, Xinyi Li, Pradipsinh K. Rathod, Xin-zhuan Su, and Liwang Cui. "Histone Acetyltransferase Inhibitor Anacardic Acid Causes Changes in Global Gene Expression during In Vitro Plasmodium falciparum Development." Eukaryotic Cell 7, no. 7 (May 16, 2008): 1200–1210. http://dx.doi.org/10.1128/ec.00063-08.

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ABSTRACT 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 activity in parasite nuclear extracts but did not affect histone deacetylase activity. AA blocked the growth of both chloroquine-sensitive and -resistant strains, with a 50% inhibitory concentration of ∼30 μM. Treatment of the parasites with 20 μM of AA for 12 h had no obvious effect on parasite growth or gross morphology but induced hypoacetylation of histone H3 at K9 and K14, but not H4 at K5, K8, K12, and K16, suggesting inhibition of the PfGCN5 HAT. Microarray analysis showed that this AA treatment resulted in twofold or greater change in the expression of 271 (∼5%) parasite genes in late trophozoites, among which 207 genes were downregulated. Cluster analysis of gene expression indicated that AA mostly downregulated active genes, and this gene pool significantly overlapped with that enriched for H3K9 acetylation. We further demonstrated by chromatin immunoprecipitation and real-time PCR that AA treatment reduced acetylation near the putative promoters of a set of downregulated genes. This study suggests that the parasiticidal effect of AA is at least partially associated with its inhibition of PfGCN5 HAT, resulting in the disturbance of the transcription program in the parasites.

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Jiang, C., G. Chen, E. Pallé, F. Murgas, H. Parviainen, F. Yan, and Y. Ma. "Evidence for stellar contamination in the transmission spectra of HAT-P-12b." Astronomy & Astrophysics 656 (December 2021): A114. http://dx.doi.org/10.1051/0004-6361/202141824.

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Context. Transmission spectroscopy characterizes the wavelength dependence of transit depth, revealing atmospheric absorption features in planetary terminator regions. In this context, different optical transmission spectra of HAT-P-12b reported in previous studies exhibited discrepant atmospheric features (e.g., Rayleigh scattering and alkali absorption). Aims. We aim to understand the atmosphere of HAT-P-12b using two transit spectroscopic observations by the Gran Telescopio Canarias (GTC) and to search for evidence of stellar activity contaminating the transmission spectra, which might be the reason behind the discrepancies. Methods. We used Gaussian processes to account for systematic noise in the transit light curves and used nested sampling for Bayesian inferences. We performed joint atmospheric retrievals using the two transmission spectra obtained by GTC OSIRIS, as well as previously published results, coupled with stellar contamination corrections for different observations. Results. The retrieved atmospheric model exhibits no alkali absorption signatures, but shows tentative molecular absorption features including H2O, CH4, and NH3. The joint retrieval of the combined additional public data analysis retrieves similar results, but with a higher metallicity. Conclusions. Based on Bayesian model comparison, the discrepancies of the transmission spectra of HAT-P-12b can be explained by the effect of different levels of unocculted stellar spots and faculae. In addition, we did not find strong evidence for a cloudy or hazy atmosphere from the joint analysis, which is inconsistent with prior studies based on the observations of the Hubble Space Telescope.

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