• 제목/요약/키워드: Transcriptional Activity

검색결과 637건 처리시간 0.132초

Flavonoids inhibit the AU-rich element binding of HuC

  • Kwak, Ho-Joong;Jeong, Kyung-Chae;Chae, Min-Ju;Kim, Soo-Youl;Park, Woong-Yang
    • BMB Reports
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    • 제42권1호
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    • pp.41-46
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    • 2009
  • Post-transcriptional regulation of mRNA stability by Hu proteins is an important mechanism for tumorigenesis. We focused on the molecular interactions between the HuC protein and AU-rich elements (AREs) to find chemical inhibitors of RNA-protein interactions using RNA electrophoretic mobility shift assay with non-radioactive probes. Screening of 52 natural compounds identified 14 candidate compounds that displayed potent inhibitory activity. Six (quercetin, myricetin, (-)-epigallocatechin gallate, ellagic acid, (-)-epicatechin gallate, and rhamnetin) were categorized as phytochemicals, and their $IC_{50}$ values were low ($0.2-1.8\;{\mu}M$).

HDAC3 acts as a negative regulator of angiogenesis

  • Park, Deokbum;Park, Hyunmi;Kim, Youngmi;Kim, Hyuna;Jeoung, Dooil
    • BMB Reports
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    • 제47권4호
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    • pp.227-232
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    • 2014
  • Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis.

STUDY OF RESVERATROL AND ITS DERIVATIVES ON THE REGULATION OG GENE EXPRESSION IN MCF-7 CELLS TRANSFECTED WITH EITHER pERE-LUC OR phCYP1A1-LUC

  • Joung, Ki-Eun;Kim, Yeo-Woon;Sheen, Yhun-Yhong
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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    • pp.111-111
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    • 2001
  • Resveratrol (trans-3,4',5-trihydroxystilbene), which is a polyphenolic compound found in a variety of plants such as grapes and wine, has been reported to have a variety of anti-inflammatory, anti-platelet, and anti-carcinogenic effects. Recently resveratrol of was reported to serve as an estrogen agonist in MCF-7 cells Based on its structural similarity to diethylstilbestrol, a synthetic estrogen, we examined whether resveratrol and its derivatives might be estrogenic using stable MCF-7-ERE cells. Resveratrol functioned as a superagonist at high concentrations (i.e., produced a greater maximal transcriptional response than estradiol) Among the resveratrol derivatives, 10 compounds showed significant estrogenic activity.

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Repression of Transcriptional Activity of Estrogen Receptor α by a Cullin3/SPOP Ubiquitin E3 Ligase Complex

  • Byun, Boohyeong;Jung, Yunhwa
    • Molecules and Cells
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    • 제25권2호
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    • pp.289-293
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    • 2008
  • The role of SPOP in the ubiquitination of $ER{\alpha}$ by the Cullin3-based E3 ubiquitin ligase complex was investigated. We showed that the N-terminal region of SPOP containing the MATH domain interacts with the AF-2 domain of $ER{\alpha}$ in cultured human embryonic 293 cells. SPOP was required for coimmunoprecipitation of $ER{\alpha}$ with Cullin3. This is the first report of the essential role of SPOP in $ER{\alpha}$ ubiquitination by the Cullin3-based E3 ubiquitin ligase complex. We also demonstrated repression of the transactivation capability of $ER{\alpha}$ in cultured mammalian cells.

New Insights into the Protein Turnover Regulation in Ethylene Biosynthesis

  • Yoon, Gyeong Mee
    • Molecules and Cells
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    • 제38권7호
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    • pp.597-603
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    • 2015
  • Biosynthesis of the phytohormone ethylene is under tight regulation to satisfy the need for appropriate levels of ethylene in plants in response to exogenous and endogenous stimuli. The enzyme 1-aminocyclopropane-1-carboxylic acid synthase (ACS), which catalyzes the rate-limiting step of ethylene biosynthesis, plays a central role to regulate ethylene production through changes in ACS gene expression levels and the activity of the enzyme. Together with molecular genetic studies suggesting the roles of post-translational modification of the ACS, newly emerging evidence strongly suggests that the regulation of ACS protein stability is an alternative mechanism that controls ethylene production, in addition to the transcriptional regulation of ACS genes. In this review, recent new insight into the regulation of ACS protein turnover is highlighted, with a special focus on the roles of phosphorylation, ubiquitination, and novel components that regulate the turnover of ACS proteins. The prospect of cross-talk between ethylene biosynthesis and other signaling pathways to control turnover of the ACS protein is also considered.

RNAi-mediated reduction of xanthine dehydrogenase results in increased biomass of Arabidopsis seedlings

  • Nakagawa, Ayami;Sakamoto, Atsushi;Takahashi, Misa;Morikawa, Hiromichi
    • 한국식물생명공학회:학술대회논문집
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    • 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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    • pp.356-360
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    • 2005
  • Xanthine dehydrogenase (XDH), a classic enzyme involved in purine catabolism, can catalyze the formation of redox-signaling reactive oxygen and nitrogen species such as superoxide and nitric oxide. We generated transgenic plants of Arabidopsis in which XDH was knocked out by introduction of hairpin RNA-expression vector. Expression analysis by reverse transcription-PCR and in-gel staining of XDH activity revealed that transgenic lines efficiently suppressedXDH expression at the transcriptional level, demonstrating that RNA interference was successfully induced. XDH-suppressed transgenic lines exhibitedincreased biomass production during the growth of seedlings.

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Role of heavy metals in human health and particularly in respect to diabetic patients

  • Asif, Mohammad
    • 셀메드
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    • 제7권1호
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    • pp.1.1-1.10
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    • 2017
  • Minerals are individual of the components of foods and are not produced in the body but essential for best possible health. Several essential metals are vital for the appropriate performance of various enzymes, transcriptional factors and proteins that are essential in various biochemical paths. Metals like zinc (Zn), magnesium (Mg), and manganese (Mn) are cofactors of hundreds of enzymes. Zn is involved in the synthesis and secretion of insulin from the pancreatic ${\beta}-cells$. Chromium (Cr) increases the insulin receptors activity on target tissues, mainly in muscle cells. Insulin hormone is required to maintain the blood glucose amount in normal range. Continual increase of blood serum glucose level leads to marked chronic hyperglycemia or diabetes mellitus. Deficiency of insulin or its resistance, blood glucose level exceeds the upper limit of the common range of 126 mg/dl. Poor glucose control and diabetes changes the levels of essential trace elements such as Zn, Mg, Mn, Cr, iron etc. by rising urinary excretion and their related decrease in the blood. The aim of this article to discusses the important roles of essential trace elements in particular perspective of type 2 diabetes.

Identification of Amino Acid Residues in the Carboxyl Terminus Required for Malonate-Responsive Transcriptional Regulation of MatR in Rhizobium leguminosarum bv. trifolii

  • Lee, Hwan-Young;Kim, Yu-Sam
    • BMB Reports
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    • 제34권4호
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    • pp.305-309
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    • 2001
  • MatR in Rhizobium trifolii is a malonate-responsive transcription factor that regulates the expression of genes, matABC, enabling decarboxylation of malonyl-CoA into acetyl-CoA, synthesis of malonyl-CoA from malonate and CoA, and malonate transport. According to an analysis of the amino acid sequence homology, MatR belongs to the GntR family The proteins of this family have two-domain folds, the N-terminal helix-turn-helix DNA-binding domain and the C-terminal ligand-binding domain. In order to End the malonate binding site and amino acid residues that interact with RNA polymerase, a site-directed mutagenesis was performed. Analysis of the mutant MatR suggests that Arg-160 might be involved in malonate binding, whereas Arg-102 and Arg-174 are critical for the repression activity by interacting with RNA polymerase.

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Mollugin-mediated Inhibition of Proinflammatory Biomarkers in Lipopolysaccharide-stimulated RAW264.7 Cells

  • Kim, Jin-Kyung;Park, Geun-Mook;Jun, Jong-Gab
    • 대한의생명과학회지
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    • 제18권4호
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    • pp.338-344
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    • 2012
  • Mollugin is the active compound of Rubia cordifolia, a well known herb widely used in alternative medicines for the treatment of various inflammatory diseases including arthritis and uteritis. In the present study, we investigated the anti-inflammatory effects of mollugin in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophage cells. Treatment with mollugin significantly inhibited LPS-induced release of nitric oxide, prostaglandin $E_2$, and inflammatory cytokines, such as tumor necrosis factor-${\alpha}$ and interleukin-6. In addition, mollugin suppressed LPS-induced nuclear factor-kappa B (NF-${\kappa}B$) transcriptional activity. These results suggest that mollugin inhibits LPS-induced expression of inflammatory molecules via NF-${\kappa}B$, at least in part, and indicate the potential value of mollugin as a valuable new drug candidate for the treatment of various inflammatory diseases.

Selection of Putative Iron-responsive Elements by Iron Regulatory Protein-2

  • Kim, Hae-Yeong
    • Journal of Applied Biological Chemistry
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    • 제42권2호
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    • pp.62-65
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    • 1999
  • Iron regulatory proteins (IRPs) 1 and 2 bind with equally high affinity to specific RNA stem-loop sequences known as iron-responsive elements (IRE) which mediate the post-transcriptional regulation of many genes of iron metabolism. To study putative IRE-like sequences in RNA transcripts using the IRP-IRE interaction, Eight known genes from database were selected and the RNA binding activity of IRE-like sequences were compared to IRP-2. Among them, the IRE-like sequence in 3'-untranslational region (UTR) of divalent ration transporter-1 (DCT-1) shows a significant RNA binding affinity. This finding predicts that IRE consensus sequence present within 3'-UTR of DCT-1 might confer the regulation by IRP-2.

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