• Title/Summary/Keyword: Regulators

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Functional Implications of the Conserved Action of Regulators of Ribonuclease Activity

  • Yeom, Ji-Hyun;Shin, Eun-Kyoung;Go, Ha-Young;Sim, Se-Hoon;Seong, Maeng-Je;Lee, Kang-Seok
    • Journal of Microbiology and Biotechnology
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    • v.18 no.8
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    • pp.1353-1356
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    • 2008
  • RNase E (Rne) plays a major role in the decay and processing of numerous RNAs in E. coli, and protein inhibitors of RNase E, RraA and RraB, have recently been discovered. Here, we report that coexpression of RraA or RraB reduces the ribonucleolytic activity in rne-deleted E. coli cells overproducing RNase ES, a Streptomyces coelicolor functional ortholog of RNase E, and consequently rescues these cells from growth arrest. These findings suggest that the regulators of ribonuclease activity have a conserved intrinsic property that effectively acts on an RNase E-like enzyme found in a distantly related bacterial species.

Distribution of root density in Pinus thunbergii Parlatore (해송(海松)의 근계밀도(根系密度)의 분포(分布)에 관(關)한 연구(硏究))

  • Joo, Sung Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.9
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    • pp.109-114
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    • 1991
  • The depth and spread of root systems and the density of root branching affect the success and survival of plants subjected to drought. The type and size of root systems are controlled by heredity and soil conditions. There are also important interaction between roots and shoots; roots are dependent on shoots for carbohydrates, growth regulators, and certain vitamins, and shoots are dependent on roots for water, minerals, and certain growth regulators. Pinus thunbergii Parlatore had most of roots in the top 20cm of soil, and had little short of roots in the less than 80cm of soil. Average of root density was $270cm/cm^3$ in the upper soil(0~20cm). Root density of Pinus thunbergii Parlatore was similar to that of Cryptomeria japonica. There is no saying that Pinus thunbergii Parlatore has an advantage over Cryptomeria japonica in the drought. This data will be used to the root density values in the simulation model of black pine stands.

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Studies on Aseptic Culture of Seed in Dendrobium Monile I. Effects of Basal Media and Growth Regulators on Germination of Seeds and Growth of Plantlet (한약자원식물인 Dendrobium monile 종자의 무균배양에 관한 연구 I. 기본배지 및 생장조절 생질이 종자의 발아와 유묘 생육에 미치는 영향 ( Studies on Aseptic Culture of Seed in Dendrobium Monile I. Effect of Basal Media and Growth Regulators on Germination of Se)

  • 최성규
    • Korean Journal of Plant Resources
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    • v.1 no.1
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    • pp.88-92
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    • 1988
  • The study was conducted to determine the optimal basal media and the concentration of plant growth regulator for germination of seeds and growth of plantlet from Dendrobium monile. The results obtained were summarized as follows. Germination was similar in light and dark condition, but the growth of plantlet after germination was better under dark than under light condition in several media. Germination was best in Hyponex and Kyoto solution medium among the 9 media tested. The number of roots/shoot was most in the Hyponex medium containing 0,1ppm NAA and 1.Oppm BA.

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Positive and negative regulation of the Drosophila immune response

  • Aggarwal, Kamna;Silverman, Neal
    • BMB Reports
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    • v.41 no.4
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    • pp.267-277
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    • 2008
  • Insects mount a robust innate immune response against a wide array of microbial pathogens. The hallmark of the Drosophila humoral immune response is the rapid production of anti-microbial peptides in the fat body and their release into the circulation. Two recognition and signaling cascades regulate expression of these antimicrobial peptide genes. The Toll pathway is activated by fungal and many Gram-positive bacterial infections, whereas the immune deficiency (IMD) pathway responds to Gram-negative bacteria. Recent work has shown that the intensity and duration of the Drosophila immune response is tightly regulated. As in mammals, hyperactivated immune responses are detrimental, and the proper down-modulation of immunity is critical for protective immunity and health. In order to keep the immune response properly modulated, the Toll and IMD pathways are controlled at multiple levels by a series of negative regulators. In this review, we focus on recent advances identifying and characterizing the negative regulators of these pathways.

MicroRNAs as critical regulators of the endothelial to mesenchymal transition in vascular biology

  • Kim, Jongmin
    • BMB Reports
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    • v.51 no.2
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    • pp.65-72
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    • 2018
  • The endothelial to mesenchymal transition (EndMT) is a newly recognized, fundamental biological process involved in development and tissue regeneration, as well as pathological processes such as the complications of diabetes, fibrosis and pulmonary arterial hypertension. The EndMT process is tightly controlled by diverse signaling networks, similar to the epithelial to mesenchymal transition. Accumulating evidence suggests that microRNAs (miRNAs) are key regulators of this network, with the capacity to target multiple messenger RNAs involved in the EndMT process as well as in the regulation of disease progression. Thus, it is highly important to understand the molecular basis of miRNA control of EndMT. This review highlights the current fund of knowledge regarding the known links between miRNAs and the EndMT process, with a focus on the mechanism that regulates associated signaling pathways and discusses the potential for the EndMT as a therapeutic target to treat many diseases.

The Effects of Various Dehiscence Materials, Growth Regulators and Fungicides on the of Ginseng Seed ( Panax ginseng C A. Meyer ) (개갑처리재료, 생장조절제 및 살충제가 고려인삼종자의 개갑에 미치는 영향)

  • 양덕조;천성기
    • Journal of Ginseng Research
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    • v.6 no.1
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    • pp.56-66
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    • 1982
  • The effects of various dehiscent application such as dehiscent materials (big chaffs, vermiculite etc.), growth regulators and agricultural chemicals (plant protector.) on stimulation of dehiscence and shortening of dehiscent period were investigated Results obtained were as follows : 1. The moisture content of endosperm and seed coat at 10 day after dehiscent application amounts between 40% and 50%. 2. Endosperm diameter was increased with time of stratification, and the embryo growth showed in linear function, 3. Non-dehiscent seed showed also normally development of embryo, and the property of dehiscence dependent from physico-chemical nature of ginseng seed coat. 4. The best dehiscent materials were big chaffs and followed vermiculite, sand and sand with big chaffs. 5. The effect of dehiscence of ginseng seed showed higher activity in fungi than in bacteria in general. 6. Agricultural chemicals ( plant Protector) reduced the dehiscent rate of ginseng seed 7. The best timing of dehiscent treatment was between August 1 and August 10 but the smaller amount of dehiscent rate after August 10 dehiscent appllication indicated that big chaffs and growth regulator treatment may be controlled shortening of dehiscent period of ginseng seed.

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Analysis of Flow and Performance of Regulator for Clean Gas Supply System (가스 조절용 레귤레이터의 유동 및 성능해석)

  • Kim, M.K.;Lee, Y.S.;Choi, W.J.;Kwon, O.B.;Park, J.
    • Journal of Power System Engineering
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    • v.13 no.1
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    • pp.13-18
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    • 2009
  • In this study, flow characteristics at the regulators, which is very important for clean gas supply systems for semiconductors and LCD industries, are investigated. Numerical simulations are carried out to visualize flows at regulators for several flow rates and to investigate pressure losses at some parts in the regulator. Velocity field at the regulator along with the detailed velocity field near the spring and near the valve is shown. New regulator models are proposed in this paper, and numerical simulations are also carried out to visualize flows at regulator for several flow rates, and to investigate pressure losses at the parts in new models. Pressure drops a lot across the valve seat. Pressure drop increases as mass flow rate increases. Especially for small opening, pressure drop increases rapidly as mass flow rate becomes large.

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Robust Stability Bounds for Discrete-Time Regulators with Computation Delays (연산지연을 가진 이산시간 레규레이터에 대한 강인한 안정성 유계)

  • 배종일
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.2
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    • pp.174-180
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    • 1998
  • Robust stability of discrete-time regulators which utilize state predictors to compensate computation delays is considered. Novel expressions for the return difference matrices and the complementary sensitivity matrices at the input and the output of the regulator are found to obtain simple bounds for unstructured perturbations. Robust stability for pertubations of the system matrix and /or the gain matrix is also considered. under certain restriction on the nominal system simple bounds for the pertubations are obtained directly from the characteristic equation. It is shown that as far as the effect of the computation delays concerns these bounds have explicit relation to those for the unstructured pertubations.

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Establishment of Regeneration System and Antibiotic Sensitivity Test for Transformation of Various Vegetable Crops (채소작물의 형질전환을 위한 재분화체계 확립 및 항생제 검정)

  • 박영두;구자정
    • Journal of Life Science
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    • v.9 no.5
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    • pp.564-569
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    • 1999
  • This study was conducted to determine the concentrations of plant growth regulators required for regeneration and the concentrations of antibiotics for the selection of transformed regenerants from lettuce, musk melon and tomato. The optimal concentrations of plant growth regulators for shoot formation were NAA 0.1 mg/$\ell$ +BA 0.1 mg/$\ell$ for lettuce, NAA 0.01 mg/$\ell$ +BA 2.0 mg/$\ell$ for melon and NAA 0.1 mg/$\ell$ +BA 0.5 mg/$\ell$for musk melon. Shoot induction from tomato, lettuce and melon was completely inhibited by 30 mg/$\ell$ or higher concentrations of kanamycin. Shoot formation from mu나 melon was not affected by kanamycin up to 40 mg/$\ell$, but was reduced in the presence of 50 mg/$\ell$ and completely inhibited by 100 mg/$\ell$. Shoot formation of all four crops was completely inhibited by higromycin at 10 mg/$\ell$. Both carbenicillin and cefatoxinme did not show any negative effects on shoot formation.

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오갈피 나무속(Acanthopanax spry.) 식물의 번식에 관한 연구 -제1보 삽목시 생장조절성질이 발근에 미치는 영향-

  • 안상득;최은옥
    • Journal of Ginseng Research
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    • v.16 no.2
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    • pp.138-145
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    • 1992
  • Rooting test of 5 species plants in Acanthopanax genus was carried out to see the comparative effect of growth regulators NAA IBA and IAA. And the results are summarized as in the following compendia; (1) When hard and soft-wood cutting from new shoot of 5 species were taken and dipping treated with growth regulators such as NAA IBA and IAA at varied concentration levels their roofings were mostly more superior to the control that untreated. And also treatment of NAA and IBA among treated substances were more effective than IAA. (2) The effects on the rooting number and rate made a great difference according to species of Acanthopanax genus even if the same regulator was treated. (3) Decreasing effects of rooting by high concentration obstacle (especially at 2,000 rpm) of NAA and IBA in other species except A. sieboldianum were mostly serious. On the other hand, that in case of IAA treatment was not risen in most species except A. sessiliflorus.

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