Ago2 and GW182 expression in mouse preimplantation embryos: a link between microRNA biogenesis and GW182 protein synthesis

Shen, Xing-Hui,Han, Young-Joon,Cui, Xiang-Shun,Kim, Nam-Hyung CSIRO Publishing 2010 Reproduction, fertility, and development Vol.22 No.4

<P> MicroRNA-mediated RNA interference appears to play a role in early development and differentiation processes in preimplantation embryos. However, the expression of its key effectors, including Ago2, a key component of the RNA-induced silencing complex, and GW182, a critical component of GW bodies (GWBs), has not been assessed in preimplantation embryos. To characterise the roles of Ago2 and GW182 in early embryo development, we determined their transcription and protein synthesis in mouse embryos. Transcript levels of Ago2 and GW182 increased steadily from the one-cell stage through to the blastocyst stage when data were not normalised against an internal reference. However, when normalised against the internal standard, transcript levels for both genes were highest in four-cell stage embryos and decreased steadily through to the blastocyst stage. Indirect immunocytochemistry showed that both AGO2 and GW182 proteins were expressed in each stage in the early embryo and were observed to colocalise in the morula and blastocyst stages. Specific silencing of mRNA expression by short interference (si) RNA against Ago2 or Dicer1 decreased the expression of selected apoptosis- and development-related microRNAs, but did not inhibit development up to the blastocyst stage. However, transcription levels of Oct3/4, Nanog and Sox2 were decreased in both Ago2- and Dicer1-knockdown embryos at the blastocyst stage. Furthermore, although knockdown of these genes did not change transcript levels of GW182, GW182 protein synthesis was decreased in blastocyst stage embryos. These results suggest that Ago2 and Dicer1 regulate GW182 protein expression in mouse embryos, which is linked to microRNA biogenesis and likely to be important for differentiation in the blastocyst stage. </P>

Characterization of Antibiotic Substance Produced by Serratia plymuthica A21-4 and the Biological Control Activity against Pepper Phytophthora Blight

Shun-Shan Shen,Feng-Zhi Piao,Byong-Won Lee,박창석 한국식물병리학회 2007 Plant Pathology Journal Vol.23 No.3

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical compound was isolated and purified by antifungal activityguided fractionation. The chemical structure was identified as a chlorinated macrolide (C23H31O8Cl) by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than 0.0625 μg/ml. The effective concentrations of the macrocyclic lactone A21- 4 for ED50 of mycelial growth inhibition were 0.25 μg/ ml, 0.25 μg/ml, 0.30 μg/ml and 0.75 μg/ml against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

Serratia plymuthica Strain A2l-4: A Potential Biocontrol Agent Against Phytophthora Blight of Pepper

Shen, Shun-Shan,Kim, Jin-Woo,Park, Chang-Seuk The Korean Society of Plant Pathology 2002 Plant Pathology Journal Vol.18 No.3

A promising biocontrol agent, A2l-4, against Phytophthora blight of pepper was selected from 351 bacterial isolates collected from rhizosphere soils and roots of onion (Allium fistulosum L.). The isolate A21-4 was identified as Serratia plymuthica based on its 16S rRNA sequence and key characteristics as compared with that of an authentic culture of S. plymuthica (ATCC No. 6109D01). The isolate readily colonized on roots of various crops including pepper when inoculated on seed and not. Strain A2l-4 showed narrow spectrum of antibiotic activity, as revealed in its strong inhibitory activity to the genera Pythium and Phytophthora, but not to Fuasrium and Rhizoctonia. In pot experiments, none of the pepper seedlings treated with A2l-4 were infected by Phytophthora capsici, while 86% of the control plants were killed by the pathogen.

Low-dose diethylhexyl phthalate exposure does not impair the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in mouse mammary glands

Shun-Feng Cheng,Ling Li,Bo Li,Jing-Cai Liu,Fang-Nong Lai,Yong Zhao,Xi-Feng Zhang,Wei Shen,Lan Li 대한독성 유전단백체 학회 2018 Molecular & cellular toxicology Vol.14 No.2

Backgrounds: Di-(2-ethylhexyl) phthalate (DEHP), as an endocrine-disrupting chemical (EDC), is widely used in plasticizer and other productions. Ubiquitous human exposure to DEHP has been proposed to be a potential risk to public health. Developmental exposure to DEHP could alter epigenetic programming and result in adult-onset disease. Methods: In this study, we investigated whether DEHP exposure to pregnant mice affected epigenetic changes as a result of increase in breast cancer incidence. Results: Our results showed that the expression of total 143 epigenetics-related genes in mammary gland cells, have no significantly altered after short time and low-dose treated with DEHP from 0.5 days post-coitum (dpc) to 3.5 dpc of pregnant mice. DNA methylation status of some neoplastic development genes, such as EGFr, Esr1, Pgr, Fos and Rassf5 also had no obvious change. Conclusion: These finding showed no impact of DEHP on the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in pregnant mouse mammary gland cells.

Root Colonizing and Biocontrol Competency of Serratia plymuthica A21-4 against Phytophthora Blight of Pepper

Shen, Shun-Shan,Choi, Ok-Hee,Park, Sin-Hyo,Kim, Chang-Guk,Park, Chang-Seuk The Korean Society of Plant Pathology 2005 Plant Pathology Journal Vol.21 No.1

The biocontrol agent Serratia plymuthica A21-4 readily colonized on the root of pepper plant and the bacterium moves to newly emerging roots continuously. The colonization of A21-4 on the pepper root was influenced by the presence ofPhytophthora capsici in the soil. When P. capsici was introduced in advance, the population density of A21-4 on the root of pepper plant was sustained more than $10^6$ cfu/g root until 3 weeks after transplanting. On the other hand, in the absence of P. capsici, the population density of A21-4 was reduced continuously and less than $10^5$ cfu/g root at 21 days after transplanting. S. plymuthica A21-4 inhibited successfully the P. capsici population in pepper root and rhizosphere soil. In the rhizosphere soil, the population density of P. capsici was not increased more than original inoculum density when A21-4 was treated, but it increased rapidly in non-treated control. Similarly, the population density of P. capsici sharply increased in the non-treated control, however the population of P. capsici in A21-4 treated plant was not increased in pepper roots. The incidence of Phytophthora blight on pepper treated with A21-4 was 12.6%, while that of non-treated pepper was 74.5% in GSNU experimental farm experiment. And in farmer's vinyl house experiment, the incidence of the disease treated with the fungicide was 27.3%, but treatment of A21-4 resulted in only 4.7% of the disease incidence, showing above 80% disease control efficacy.

Enhancement of Biocontrol Efficacy of Serratia plymuthica A21-4 Against Phytophthora Blight of Pepper by Improvement of Inoculation Buffer Solution

Shen, Shun-Shan,Park, Sin-Hyo,Park, Chang-Seuk The Korean Society of Plant Pathology 2005 Plant Pathology Journal Vol.21 No.1

The production of antibiotic substances by Serratia plymuthica A21-4 was greatly enhanced by modifying components of a growth medium. When the minimal medium containing $K_2HPO_4$ 0.7%, $KH_2PO_4$ 0.2%, $(NH_4)_2SO_4$ 0.1%, $MgSO_4$ 0.01% was used as basal medium, the best carbon source for antibiotic production was glycerol and the most favorable nitrogen source was ammonium sulfate. The modified medium for antibiotic production also increased colonization ability of A21-4 on pepper root and in the rhizosphere soil. When the cells of A21-4 were suspended in modified medium, the population density of A21-4 on pepper root was 10-100 times higher than that suspended in 0.1 M $MgSO_4$. The population density of A21-4 on root did not decrease under $10^6$ cfu/groot up to 21 days after treatment although the inoculum of A21-4 was reduced to $10^7$ cell/ml. Similar tendency was also observed in the rhizosphere soil. Consequently, Phytophthora blight of pepper was successfully controlled by A21-4 with $10^7$ cell/ml suspended in the modified buffer solution instead of $10^9$ cfu/ml suspended in 0.1 M $MgSO_4$.

Memory-dependent derivatives theory of thermo-viscoelasticity involving two-temperature

Shun-Fa Hwang,Min-Chien Shen,Bin-Bin Hsu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.10

A new model of two-temperature generalized thermo-viscoelasticity theory based on memory-dependent derivative is constructed. Theequations of the new model are applied to one-dimensional problem of a half-space. The bounding surface is taken to be traction free andsubjected to a time dependent thermal shock. Laplace transforms technique is used. A direct approach is applied to obtain the exact formulasof heat flux, temperature, stresses, displacement and strain in the Laplace transform domain. Application is employed to our problemto get the solution in the complete form. The considered variables are presented graphically and discussions are made.

Characterization of Antibiotic Substance Produced by Serratia plymuthica A21-4 and the Biological Control Activity against Pepper Phytophthora Blight

Shen, Shun-Shan,Piao, Feng-Zhi,Lee, Byong-Won,Park, Chang-Seuk The Korean Society of Plant Pathology 2007 Plant Pathology Journal Vol.23 No.3

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

Strain measurement of polymer materials by digital image correlation combined with finite-element analysis

Shun-Fa Hwang,Min-Chien Shen,Bin-Bin Hsu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.10

Digital image correlation (DIC) can provide deformation information of a specimen by processing its two digital images captured beforeand after the deformation. In this study, a DIC method based on a modified coarse–fine iterative method is combined with finiteelementanalysis to obtain the strain and displacement data. This method is first verified with the use of an aluminum specimen underuniaxial testing. For polymer materials, polypropylene specimens with and without short glass fibers and polydimethylesiloxane specimenswith and without dyes are tested. Results indicate that the present method can capture the strains of these specimens even underhigh elongation and without artificial speckle pattern on their surfaces. Thus, the mechanical behavior of polymer materials can be characterizedand the effects of additional ingredients added to the materials can be assessed through the developed DIC method.

Enhancement of Biocontrol Efficacy of Serratia plymuthica A21-4 Against Phytophthora Blight of Pepper by Improvement of Inoculation Buffer Solution

Shun-Shan Shen,박창석,Sin-Hyo Park 한국식물병리학회 2005 Plant Pathology Journal Vol.21 No.1

The production of antibiotic substances by Serratia plymuthica A21-4 was greatly enhanced by modifying components of a growth medium. When the minimal medium containing K2HPO4 0.7%, KH2PO4 0.2%,(NH4)2SO4 0.1%, MgSO4 0.01% was used as basal medium, the best carbon source for antibiotic production was glycerol and the most favorable nitrogen source was ammonium sulfate. The modified medium for antibiotic production also increased colonization ability of A21-4 on pepper root and in the rhizosphere soil. When the cells of A21-4 were suspended in modified medium, the population density of A21-4 on pepper root was 10-100 times higher than that suspended in 0.1 M MgSO4. The population density of A21-4 on root did not decrease under 106 cfu/groot up to 21 days after treatment although the inoculum of A21-4 was reduced to 107 cell/ml. Similar tendency was also observed in the rhizosphere soil. Consequently, Phytophthora blight of pepper was successfully controlled by A21-4 with 107 cell/ml suspended in the modified buffer solution instead of 109 cfu/ml suspended in 0.1 M MgSO