• Title/Summary/Keyword: ERF

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Computation of the ERF from the OTF (OTF계산값을 이용한 ERF계산)

  • 심상현
    • Korean Journal of Optics and Photonics
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    • v.4 no.2
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    • pp.140-144
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    • 1993
  • A computer program for computing the edge response function(ERF) from the optical transfer function( 0TF) was developed. The ERFs of un-aberrated optical system and aberrated optical system were studied by the use of that program. We calculated the ERFs of the optical systems with a single aberration and with a combined aberration. In sagittal case, the ERE of the optical system with defocus or spherical aberration was worse than that with coma. In tagential case, the ERF of the optical system with coma was worse than that with defocusing or spherical aberraion. Both the shape and the position of ERF were varied with coma, but only the position of ERF was varied with distortion, in tangential case.

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Expression of Hr-Erf Gene during Ascidian Embryogenesis

  • Kim, Jung Eun;Lee, Won Young;Kim, Gil Jung
    • Development and Reproduction
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    • v.17 no.4
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    • pp.389-397
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    • 2013
  • FGF9/16/20 signaling pathway specify the developmental fates of notochord, mesenchyme, and neural cells in ascidian embryos. Although a conserved Ras/MEK/Erk/Ets pathway is known to be involved in this signaling, the detailed mechanisms of regulation of FGF signaling pathway have remained largely elusive. In this study, we have isolated Hr-Erf, an ascidian orthologue of vertebrate Erf, to elucidate interactions of transcription factors involved in FGF signaling of the ascidian embryo. The Hr-Erf cDNA encompassed 3110 nucleotides including sequence encoded a predicted polypeptide of 760 amino acids. The polypeptide had the Ets DNA-binding domain in its N-terminal region. In adult animals, Hr-Erf mRNA was predominantly detected in muscle, and at lower levels in ganglion, gills, gonad, hepatopancreas, and stomach by quantitative real-time PCR (QPCR) method. During embryogenesis, Hr-Erf mRNA was detected from eggs to early developmental stage embryos, whereas the transcript levels were decreased after neurula stage. Similar to the QPCR results, maternal transcripts of Hr-Erf was detected in the fertilized eggs by whole-mount in situ hybridization. Maternal mRNA of Hr-Erf was gradually lost from the neurula stage. Zygotic expression of Hr-Erf started in most blastomeres at the 8-cell stage. At gastrula stage, Hr-Erf was specifically expressed in the precursor cells of brain and mesenchyme. When MEK inhibitor was treated, embryos resulted in loss of Hr-Erf expression in mesenchyme cells, and in excess of Hr-Erf in a-line neural cells. These results suggest that zygotic Hr-Erf products are involved in specification of mesenchyme and neural cells.

Anti-nociceptive Properties of Ribes fasciculatum

  • Kim, Jin Kyu;Im, Jun Sang;Kim, Bong Seok;Cha, Dong Seok;Kwon, Jin;Oh, Chan Ho;Ma, Sang Yong;Yu, Ju Hee;Nam, Jung Il;Jeon, Hoon
    • Natural Product Sciences
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    • v.19 no.4
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    • pp.311-315
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    • 2013
  • Ribes fasciculatum (Saxifragaceae) has been widely used as a traditional medicine for the treatment of cough, antidote, cold, lacquer poison, and sore throat. In the present study, we evaluated the anti-nociceptive effects of ethyl acetate fraction of Ribes fasciculatum (ERF) in mice. Test results of tail-immersion test and hot plate test revealed that the ERF had strong anti-nociceptive activities on thermal nociception in a dose dependent manner, indicating ERF's anti-nociception on the central pain. Moreover, the acetic acid-induced chemical nociception was also significantly reduced by ERF treatment. This result shows that ERF may also work on the peripheral pain. We further performed formalin test to confirm ERF's anti-nociceptive properties and found that pain responses were significantly decreased by ERF treatment. Interestingly, in the combination test with naloxone, the analgesic activity of ERF was not changed, indicating that the opioid receptor was not involved in the ERF-mediated anti-nociception. These results indicate that ERF might be possibly used as a painkiller for the treatment of nociceptive pains.

AtERF73/HRE1, an Arabidopsis AP2/ERF Transcription Factor Gene, Contains Hypoxia-responsive Cis-acting Elements in Its Promote (애기장대의 AP2/ERF 전사인자인 AtERF73/HRE1의 프로모터에 있어서 저산소 반응 cis-조절 요소의 분석)

  • Hye-Yeon Seok;Huong Thi Tran;Sun-Young Lee;Yong-Hwan Moon
    • Journal of Life Science
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    • v.33 no.1
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    • pp.34-42
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    • 2023
  • In a signal transduction network, from the perception of stress signals to stress-responsive gene ex- pression, binding of various transcription factors to cis-acting elements in stress-responsive promoters coordinate the adaptation of plants to abiotic stresses. Among the AP2/ERF transcription factor family genes, group VII ERF genes, such as RAP2.12, RAP2.2, RAP2.3, AtERF73/HRE1, and AtERF71/ HRE2, are known to be involved in the response to hypoxia stress in Arabidopsis. In this study, we dissected the HRE1 promoter to identify hypoxia-responsive region(s). The 1,000 bp upstream promoter region of HRE1 showed increased promoter activity in Arabidopsis protoplasts and transgenic plants under hypoxia conditions. Analysis of the promoter deletion series of HRE1, including 1,000 bp, 800 bp, 600 bp, 400 bp, 200 bp, 100 bp, and 50 bp upstream promoter regions, using firefly luciferase and GUS as reporter genes indicated that the -200 to -100 region of the HRE1 promoter is responsible for the transcriptional activation of HRE1 in response to hypoxia. In addition, we identified two putative hypoxia-responsive cis-acting elements, the ERF-binding site and DOF-binding site, in the -200 to -100 region of the HRE1 promoter, suggesting that the expression of HRE1 might be regulated via the ERF transcription factor(s) and/or DOF transcription factor(s). Collectively, our results suggest that HRE1 contains hypoxia-responsive cis-acting elements in the -200 to -100 region of its promoter.

The Study on Pharmacological Activation as Cosmetic Material of Rosa rugosa Thunb. Flowers Extract (해당화꽃 추출물의 화장품소재로서 약리활성에 관한 연구)

  • Yu, Hye-Soo;Choi, Ji-Eun;Woo, Won-Hong;Mun, Yeun-Ja
    • Korean Journal of Acupuncture
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    • v.31 no.4
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    • pp.188-194
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    • 2014
  • Objectives : In this study, we investigated the effect of ethanol extract from Rosa rugosa Thunb. flowers(ERF) on the activities of antioxidant, antiwrinkle and whitening. Methods : We measured antioxidant efficacy of ERF by using 1,1-diphenyl-2-picrylhydrazyl(DPPH) assay. Also we confirmed the inhibitory effect of ERF on collagenase activity and melanin synthesis by using collagenase assay kit and dihydroxiphenylalanine staining, respectively. To evaluate the anti-inflammatory effects of ERF, we examined the inflammatory mediator IL-6. Results : ERF showed highly efficacy in DPPH radical scavenging activity. ERF dose-dependently suppressed collagenase activity. Ultraviolet-induced production of IL-6 decreased by ERF treatment. In B16F10 cell, ERF significantly reduced tyrosinase activity and melanin synthesis. Conclusions : From the above results, it was indicated that ERF could be utilized as anti-aging and whitening cosmetic ingredients.

Analysis of Putative Downstream Genes of Arabidopsis AtERF71/HRE2 Transcription Factor using a Microarray (마이크로어레이를 이용한 애기장대 AtERF71/HRE2 전사인자의 하위 유전자 분석)

  • Seok, Hye-Yeon;Lee, Sun-Young;Woo, Dong-Hyuk;Park, Hee-Yeon;Moon, Yong-Hwan
    • Journal of Life Science
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    • v.22 no.10
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    • pp.1359-1370
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    • 2012
  • Arabidopsis AtERF71/HRE2, a transcription activator, is located in the nucleus and is involved in the signal transduction of low oxygen and osmotic stresses. In this study, microarray analysis using AtERF71/HRE2-overexpressing transgenic plants was performed to identify genes downstream of AtERF71/HRE2. A total of 161 different genes as well as AtERF71/HRE2 showed more than a twofold higher expression in AtERF71/HRE2-overexpressing transgenic plants compared with wild-type plants. Among the 161 genes, 24 genes were transcriptional regulators, such as transcription factors and DNA-binding proteins, based on gene ontology annotations, suggesting that AtERF71/HRE2 is an upstream transcription factor that regulates the activities of various downstream genes via these transcription regulators. RT-PCR analysis of 15 genes selected out of the 161 genes showed higher expression in AtERF71/HRE2-overexpressing transgenic plants, validating the microarray data. On the basis of Genevestigator database analysis, 51 genes among the 161 genes were highly expressed under low oxygen and/or osmotic stresses. RT-PCR analysis showed that the expression levels of three genes among the selected 15 genes increased under low oxygen stress and another three genes increased under high salt stress, suggesting that these genes might be downstream genes of AtERF71/HRE2 in low oxygen or high salt stress signal transduction. Microarray analysis results indicated that AtERF71/HRE2 might also be involved in the responses to other abiotic stresses and also in the regulation of plant developmental processes.

Anti-inflammatory Effect of Ribes fasciculatum in IFN-${\gamma}$/LPS-stimulated Mouse Peritoneal Macrophage

  • Kim, Jin Kyu;Kim, Ha Na;Kang, Chung Sik;Seo, Je Han;Seo, Hyun Won;Im, Jun Sang;Kim, Bong Seok;Cha, Dong Seok;Kwon, Jin;Oh, Chan Ho;Ma, Sang Yong;Nam, Jung Il;Jeon, Hoon
    • Natural Product Sciences
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    • v.20 no.2
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    • pp.113-118
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    • 2014
  • Ribes fasciculatum which belongs to Saxifragaceae has been widely used as a traditional medicine for the treatment of symptoms associated with lacquer poison. However, pharmacological studies on the R. fasciculatum are extremely limited until now. Thus, in this study, we evaluated the possible anti-inflammatory effects of ethyl acetate fraction of R. fasciculatum (ERF) using IFN-${\gamma}$/LPS-stimulated peritoneal macrophage model. We investigated the change in nitrite level in the absence or presence of ERF after LPS stimulation, and we found that ERF effectively attenuates the NO production in a dose dependent manner without notable toxicity. To determine the mechanism of the inhibitory action of ERF on NO production, we performed iNOS enzyme activity assay and Western blotting. Here we showed that both of iNOS enzyme activities and iNOS expressions were significantly down-regulated by ERF, indicating that these dual activities of ERF are responsible for ERF-mediated NO suppression. In addition, ERF inhibitied the expression of cyclooxygenase-2 (COX-2), an another key enzyme in inflammation through suppression of NF-${\kappa}B$ activation. We also tested anti-inflammatory properties of ERF not only in vitro, but in vivo using trypsin-induced paw edema model in mice. Our results revealed that the increased paw volume in response to trypsin injection was recovered by ERF supplement dose dependently.

STUDY ON TORQUE CONVERTER USING ELECTRO-RHEOLOGICAL FLUID (존가점성 유체를 이용한 동력전달 장치에 관한 연구)

  • 이은준;박명관;주동우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.542-545
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    • 1995
  • This paper provides an investigation of torque converter system using ERF (Electro-Rheological Fluid). The torque converter system using ERP is a new concepting device because we can change an apparent viscosity of ERF by adapting an electric field. The device was designed by using the equations which were proposed by Carlson et al. The devices based on ERF generally assume one two possible forms. One is the parallel plate type in which the device elements are facing circular disks separated by a flat layer of ERF, The other is coaxial cylinder or Couette types in which the ERF file the annular apace between a pair of coaxial cylindrical electrode. The discussion on this study is specifically for coaxial cylinder gemetry and experiment results show that the measured torque was rapidly increased with the increase of the eletric field.

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Rheological Characteristics of ER Fluids at High Pressure-Driven Flow Mode (높은 압력차의 유동모드 하에서 ER유체의 유변특성)

  • 이호근;최승복;정재천;강윤수;서문석
    • The Korean Journal of Rheology
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    • v.11 no.1
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    • pp.1-8
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    • 1999
  • This paper experimentally investigates the steady shear behaviors of electro-rheological(ER) fluids under flow mode at high pressure level. As for the ER fluid to be tested, two types of ER fluids are employed; water-based ER fluids (ERF 1, ERF 2) and water-free ER fluid(ERF 3). The water-based ER fluids are composed inhousingly, and the concentrations of dispersed particles are 20 wt% and 30 wt% for ERF 1 and ERF 2, respectively. To generate the flow mode at high pressure, an experimental apparatus operated by two-way hydraulic cylinder is constructed and utilized. The pressure difference is measured by the pressure sensor, while the flow rate is calculated using the measured data of the displacement sensor(LVDT). Consequently, the shear stress and shear rate are distilled by incorporating the measured data; the pressure difference and the flow rate.

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AtERF11 is a positive regulator for disease resistance against a bacterial pathogen, Pseudomonas syringae, in Arabidopsis thaliana (애기장대 AtERF11 유전자에 의한 Pseudomonas syringae에 대한 병 저항성 유도)

  • Kwon, Tack-Min;Jung, Yun-Hui;Jeong, Soon-Jae;Yi, Young-Byung;Nam, Jae-Sung
    • Journal of Life Science
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    • v.17 no.2 s.82
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    • pp.235-240
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    • 2007
  • AvrRpt2 protein triggers hypersensitive response (HR) and strong disease resistance when it is translocated from a bacterial pathogen Pseudomonas sp. to host plant cells containing a cognate RPS2 resistance protein through Type III Secretion System (TTSS). However, AvrRpt2 protein can function as the effector that suppresses a basal defense and enhances the disease symptom when functional RPS2 resistance protein is absent in the infected plant cells. Using Affymetrix Arabidopsis DNA chip, we found that many genes were specifically regulated by AvrRpt2 protein in the rps2 Arabidopsis mutant. Here, we showed that expression of AtERF11 that is known as a member of B1a subcluster of AP2/ERF transcription factor family was down regulated specifically by AvrRpt2. To determine its function in plant resistance, we also generated the Arabidopsis thaliana transgenic plants constitutively overexpressing AtERF11 under CaMV 355 promoter, which conferred an enhanced resistance against a bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. Thus, these results collectively suggest that AtERF11 plays a role as a positive regulator for disease resistance against biotrophic bacterial pathogen in plant.