• Molecules and Cells
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• v.26 no.2
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• pp.146-151
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• 2008

The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.

• BMB Reports
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• v.46 no.5
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• pp.282-287
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• 2013

Cecropin A and papiliocin are novel 37-residue cecropin-like antimicrobial peptides isolated from insect. We have confirmed that papiliocin possess high bacterial cell selectivity and has an ${\alpha}$-helical structure from $Lys^3$ to $Lys^{21}$ and from $Ala^{25}$ to $Val^{35}$, linked by a hinge region. In this study, we demonstrated that both peptides showed high antimicrobial activities against multi-drug resistant Gram negative bacteria as well as fungi. Interactions between these cecropin-like peptides and phospholipid membrane were studied using CD, dye leakage experiments, and NMR experiments, showing that both peptides have strong permeabilizing activities against bacterial cell membranes and fungal membranes as well as $Trp^2$ and $Phe^5$ at the N-terminal helix play an important role in attracting cecropin-like peptides to the negatively charged bacterial cell membrane. Cecropin-like peptides can be potent peptide antibiotics against multi-drug resistant Gram negative bacteria and fungi.

• Journal of the Korean Wood Science and Technology
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• v.40 no.4
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• pp.229-236
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• 2012

This study was conducted to investigate the effect of gamma radiation on cell wall degradation, cellulose crystallinity, and flexural strength of Pinus densiflrora, Zelkova serrenata, and Paulownia tomentosa. By the gamma radiation at the dose up to 100 kGy, the cell wall degradation was not detected with scanning electron microscope (SEM) observation from all samples, and the flexural strength was not significantly changed. Cellulose crystallinity was neither changed by the gamma radiation. This high stability of wood against gamma radiation means that the radiation technology can be used for eradicating fungal and insect infestation of wood without the changes in wood properties.

• The Korean Journal of Zoology
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• v.11 no.4
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• pp.103-117
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• 1968

Insect hemocytes during metamorphosis were studies by histchemical and autoradiographic methods is Pieris rapae (Lepidoptera). The hemocytes were classified into six types, prohemocytes, plasmatocytes, podocytes, granular hemocytes, spherule cells and oenocytoids on the basis of the transitions in shapes and inclnsions of cytoplasms. Proteins, nucleic acids, polysaccharides and lipids in the hemocytes were detected histochemically from larval to pupal stages to learn the rise and fall of them during growth and metamorphosis. Most of the granules consisted of glycogen, neutral mucopolysaccharides and mucoprotein in addition to some granules of neutral fats and phospholipids were found in the granular hemocytes and spherule cells. Mitotic figures and DNA synthetic activities were observed in every type of hemocytes from 2nd to 5th instars, suggesting the all types of hemocytes originated from the prohemocytes. The cytoplasmic filaments of plasmatocytes and pdocytes extended very long in prepupa and pupa and the vermiform cells were the transformed plasmatocytes due to their further differentiation.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.40-45
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• 2006

The baculovirus-insect Drosophila melanogaster S2 cell system combines advantages of conventional baculovirus system and non-lytic S2 cell system because baculoviruses can infect non-permissive cells such as mammalian and Drosophila S2 cells but cannot replicate themselves inside the cells. In the present work, we investigated effects of infection conditions on production of green fluorescent protein (GFP) as a target protein using this baculovirus-S2 cell system. Even though higher MOI and longer baculovirus contact time showed better GFP expression yield during the shorter period, overall protein yield could be lower during the longer period due to the relatively higher cell detachment and lysis (lower cell viability). In addition, maintaining high MOI will be not practical for large-scale cell culture. Therefore, instead of maintaining high MOI, we found that high initial cell number and concentrated (10X) baculovirus volume can confer comparable protein expression even under the moderate MOI condition. Also, we found that the post-infection time that is connected to state of cells after infection was an important factor for production yield.

• Journal of Life Science
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• v.25 no.5
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• pp.607-614
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• 2015

Cancers are the largest cause of mortality and morbidity all over the world. Cordycepin, an adenosine analog, is a major functional component of the Cordyceps species, which has been widely used in traditional Oriental medicine. Over the last decade, this compound has been reported to possess many pharmacological properties, such as an ability to enhance immune function, as well as anti-inflammatory, antioxidant and anti-cancer effects. Recently, numerous studies have reported interesting properties of cordycepin as a chemopreventive agent as well. There is an accumulating body of experimental evidences suggesting that cordycepin impedes cancer progression by promoting apoptosis, inducing cell cycle arrest, modulating intracellular signaling pathways, and inhibiting invasion and metastasis of cancer cells. In many cancer cell lines, cordycepin inhibits growth and cell cycle progression by inducing arrest of the G2/M phase, resulting from the inhibition of retinoblastoma protein phosphorylation and induction of cyclin-dependent kinase inhibitors. To induce apoptosis, cordycepin activates the extrinsic and intrinsic pathways, which promotes reactive oxygen species generation and the downstream activation of kinase cascades. Cordycepin also can activate alternative pathways to cell death such autophagy. In addition, cordycepin can inhibit the pro-metastatic processes of cancer cell detachment, migration, and invasion through a variety of mechanisms, including the nuclear factor-kappa B and activated protein-1 signaling pathways. In this review, we summarized the variety of action mechanisms by which cordycepin may mediate chemopreventive effects on cancer and discussed the potential of this natural product as a promising therapeutic inhibitor of cancer development.

• Biomolecules & Therapeutics
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• v.7 no.4
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• pp.307-314
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• 1999

The human muscarinic acetylcholine receptor (mAChR) subtypes Hml, Hm2 and Hm3 have been expressed in insect cells (Spodoptera frugiperda, Sf9) using the baculovirus expression system. Expression of relevant DNA, transcript and receptor proteins was identified by PCR, Northern blotting and [$^{3}H$]QNB binding, respectively. As assessed by [$^{3}H$]QNB binding sites, yields of muscarinic receptors in membrane preparations in this study were as about 5-20 times high as those in mammalian cells reported in previous studies. The [$^{3}H$]QNB competition binding studies with well-known subtype-selective mAChR antagonists showed that the receptors expressed in Sf9 cells retain the pharmacological characteristics expected for the ml , m2 and m3 muscarinic receptors. The ml-selective antagonist, pirenzepine, displayed a considerably higher affinity for Hml by 110-fold and 35-fold than for Hm2 and Hm3, respectively, The m2-selective methoctramine displayed a significantly higher affinity for Hm2 than for Hml and Hm3 (10- and 26-fold, respectively). p-F-HHSiD exhibited high affinity for Hm3 that is not significantly different from those for Hml, but 66-fold higher than its affinity for Hm2. The functional coupling of the recombinant receptors to second messenger systems was also examined. While both Hml and Hm3 stimulated phosphoinositide hydrolysis upon activation by carba-chol, Hm2 produced no response. On the other hand, activation of mAChRs induced the inhibition of forsko-lin-stimulated cyclic AMP formation in Hm2-expressing cells, whereas the significant dose-dependent increase in or poor response on cyclic AMP formation were produced in Hml or Hm3-expressing cells, respectively. These results indicate the differential coupling of recombinant Hml, Hm2 and Hm3 receptors expressed in SF9 cells to intracellular signalling system.

• Journal of Haehwa Medicine
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• v.25 no.1
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• pp.71-86
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• 2016

Objective : Hongyi (Formica yessensis) is the dried insect of fomicidae. In previous studies, it appeared possibilities on anti-thrombosis, preventing atherosclerosis, treating rheumatoid disease, and inhibiting hela cell. In this study, we investigated anti-inflammatory effects and mechanism of Hongyi. Methods : Hongyi A was extracted by water and made dried powder. Hongyi B was extracted by ethanol and made dried powder. We measured Nitric Oxide (NO) production on the mouse macrophages (RAW 264.7), mouse vascular endothelial cell (MOVAS) and human vascular endothelial cell (HUVEC) for anti-inflammatory effect. In addition, we conducted reverse transcription reaction (RT-PCR) for investigating the mechanism. Results : In RAW 264.7 macrophages stimulated by LPS, Hongyi A ($100{\mu}g/m{\ell}$) decreased NO production compared with LPS $2{\mu}g/ml$ control group with statistical significance (p<0.05). Hongyi A (50, $100{\mu}g/m{\ell}$) also decreased NO production compared with LPS $4{\mu}g/ml$ control group with statistical significance (p<0.01). Hongyi B (50, $100{\mu}g/m{\ell}$) decreased NO production compared with LPS $2{\mu}g/ml$ control group with statistical significance (p<0.01). Hongyi B (10, 50, $100{\mu}g/m{\ell}$) also decreased NO production compared with LPS $4{\mu}g/ml$ control group with statistical significance (p<0.01, p<0.001, p<0.001). In the MOVAS, Hongyi A and B increased NO production compared with control group. In the HUVEC, Hongyi B increased NO production compared with control group. The expression of NF-${\kappa}B$ in 12-hours MOVAS culture was decreased by Hongyi A and B (10, $50{\mu}g/ml$) compared with control group, but expression of $I{\kappa}B$ was increased. In the 24-hours MOVAS culture, expression of $I{\kappa}B$ was significantly increased. The expression of NF-${\kappa}B$ in 12-hours HUVEC culture was decreased by Hongyi A and B compared with control group, but expression of $I{\kappa}B$ was increased. Hongyi B also increased eNOS mRNA gene expression. Conclusions : Hongyi A and B showed anti-inflammatory effect in mouse macrophages with the activation of vascular endothelial cell through NO production in MOVAS and HUVEC repectively. Honyi B showed superior effect than Hongyi A, but additonal mechanism study should be conducted.

• Mycobiology
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• v.46 no.2
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• pp.114-121
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• 2018

Mon1 is a guanine nucleotide exchange factor subunit that activates the Ypt7 Rab GTPase and is essential for vacuole trafficking and autophagy in eukaryotic organisms. Here, we identified and characterized the function of Mon1, an ortholog of Saccharomyces cerevisiae Mon1, in a human fungal pathogen, Cryptococcus neoformans. Mutation in mon1 resulted in hypersensitivity to thermal stress. The mon1 deletion mutant exhibited increased sensitivity to cell wall and endoplasmic reticulum stress. However, the mon1 deletion mutant showed more resistance to the antifungal agent fluconazole. In vivo studies demonstrated that compared to the wild-type strain, the mon1 deletion mutant attenuated virulence in the Galleria mellonella insect model. Moreover, the mon1 deletion mutant was avirulent in the murine inhalation model. These results demonstrate that Mon1 plays a crucial role in stress survival and pathogenicity in C. neoformans.

• YAKHAK HOEJI
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• v.42 no.3
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• pp.248-256
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• 1998

We had already reported that we purified N-${\beta}$-alanyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine (5-S-GAD), a novel antibacterial substance from the immunized adult Sarcoph aga peregrina (Flesh fly). We found that the antibacterial activity of synthetic 5-S-GAD is equal to that of authentic 5-S-GAD without a specificity of antibacterial activity against Gram positive and Gram negative. Significant synergism was detected between 5-S-GAD and streptomycin against streptomycin resistant strain E.coli K12 594. It has an antitumor activity against several tumor cell lines at a concentration of $100{\mu}M$. However, no cytotoxic activity against murine macrophage was detected at a concentration of $500{\mu}M$. Furthermore, haemolytic activity against sheep erythrocytes was not detected at the same concentration. We suggest that the S-conjugation of glutathion with dihydroxyphenylalanine might be important to increase antibacterial activity of dihydroxyphenylalanme.