• The Plant Pathology Journal
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• v.21 no.2
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• pp.158-163
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• 2005

Virus-induced gene silencing (VIGS) is a recently developed gene transcript suppression technique for characterizing the function of plant genes. However, efficient VIGS has only been studied in a few plant species. In order to extend the application of VIGS, we examined whether a VIGS vector based on TRV would produce recognizable phenotypes in soybean. Here, we report that VIGS using the Tobacco rattle virus (TRV) viral vector can be used in several soybean cultivars employing various agro-inoculation methods including leaf infiltration, spray inoculation, and agrodrench. cDNA fragments of the soybean phytoene desaturase(PDS) was inserted into TRV RNA-2 vector. By agrodrench, we successfully silenced the expression of PDS encoding gene in soybean. The silenced phenotype of PDS was invariably obvious 3 weeks after inoculation with the TRV-based vector. Real-time RT-PCR analyses showed that the endogenous level of GmPDS transcripts was dramatically reduced in the silenced leaf tissues. These observations confirm that the silenced phenotype is closely correlated with the pattern of tissue expression. The TRV-based VIGS using agrodrench can be applied to functional genomics in a soybean plants to study genes involved in a wide range of biological processes. To our knowledge, this is the first high frequency VIGS method in soybean plants.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.165-174
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• 2018

Glioblastoma multiforme is the most lethal malignant brain tumor. Despite many intensive studies, the prognosis of glioblastoma multiforme is currently very poor, with a median overall survival duration of 14 months and 2-year survival rates of less than 10%. Although viral infections have been emphasized as potential cofactors, their influences on pathways that support glioblastoma progression are not known. Some previous studies indicated that human Kaposi's sarcoma-associated herpesvirus (KSHV) was detected in healthy brains, and its microRNA was also detected in glioblastoma patients' plasma. However, a direct link between KSHV infection and glioblastoma is currently not known. In this study, we infected glioblastoma cells and glioma stem-like cells (GSCs) with KSHV to establish an in vitro cell model for KSHV-infected glioblastoma cells and glioma stem-like cells in order to identify virologic outcomes that overlap with markers of aggressive disease. Latently KSHV-infected glioblastoma cells and GSCs were successfully established. Additionally, using these cell models, we found that KSHV infection modulates the proliferation of glioma stem-like cells.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.122-123
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• 2003

Apple stem grooving virus (ASGV) belongs to Capillovirus and infects pome fruits. Transmission mode of ASGV is known by grafting and mechanical inoculation into susceptible hosts, not by any other natural vectors. But we have observed the spread of ASGV in the field without mechanical inoculation or grafting. Transmission seems to be occurred from tree-to-tree and tree-to-susceptible herbaceous plants along but not across ditches in the field. In order to ascertain this possibility, various fungi were isolated and cultured from ASGV-infected plants and 69 isolates were characterized. By means of RNA dot-blot hybridization and PCR analysis, 3 isolates were sorted out for further studies. The isolates were identified to Tataromyces sp. and belonged to Phenicillium by morphological characteristics and molecular markers. As an experimental host, 10 kidney beans (Phaseolus vulgaris) were screened and Kyunggi-5 was selected for virus amplification and symptom development. Kyunggj-5 infected by fungi which seemed to carry ASGV showed the typical disease symptoms and viral coat protein genes were detected from all tested plants. To confirm the Koch's rule, fungi cultured from inoculation origins of kidney bean were grown on PDA media and re-inoculated to hosts. The fungi isolated from inoculation origins induced the typical disease symptoms on hosts. However virus free fungi did not induce any symptom on the experimental hosts. This bioassay showed that these typical symptoms were caused by virus, not fungi.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.81.2-82
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• 2003

Plants have evolved along with pathogens, and they have developed sophisticated defense systems against specific microorganisms to survive. G-protons are considered one of the upstream signaling components working as a key for the defense signal transduction pathway. For activation and inactivation of G-protein, GTP-biding proteins are involved. GTP -binding proteins are found in all organisms. Small GTP-binding proteins, having masses of 21 to 30kD, belong to a superfamily, often named the Ras supefamily because the founding members are encoded by human Ras genes initially discovered as cellular homologs of the viral ras oncogene. Members of this supefamily share several common structural features, including several guanine nucleotide binding domains and an effector binding domain. However, exhibiting a remarkable diversity in both structure and function. They are important molecular switches that cycle between the GDP-bound inactive form into the GTP-bound active form through GDP/GTP replacement. In addition, most GTP-binding proteins cycle between membrane-bound and cytosolic forms. such as the RAC family are cytosolic signal transduction proteins that often are involved in processing of extracellular stimuli. Plant RAC proteins are implicated in regulation of plant cell architecture secondary wall formation, meristem signaling, and defense against pathogens. But their molecular mechanisms and functions are not well known. We isolated a RacB homolog from rice to study its role of defense against pathogens. We introduced the constitutively active and the dominant negative forms of the GTP-hinging protein OsRacB into the wild type rice. The dominant negative foms are using two forms (full-sequence and specific RNA interference with RacB). Employing southern, and protein analysis, we examine to different things between the wild type and the transformed plant. And analyzing biolistic bombardment of onion epidermal cell with GFP-RacB fusion protein revealed association with the nucle.

• BMB Reports
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• v.42 no.10
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• pp.655-660
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• 2009

The potential anti-metastasis and anti-invasion activities of early growth response gene-1 (Egr-1) and claudin-3, a tight junction (TJ)-related protein, were evaluated using histone deacetylase (HDAC) inhibitors in human hepatocarcinoma cells. The results of wound healing and Transwell assays showed that HDAC inhibitors such as trichostatin A and sodium butyrate inhibited cell migration and invasion. HDAC inhibitors markedly induced Egr-1 expression during the early period, after which expression levels decreased. In addition, the down-regulation of snail and type 1 insulin-like growth factor receptor (IGF-1R) in HDAC inhibitor- treated cells induced the upregulation of thrombospondin-1 (TSP-1), E-cadherin and claudin-3. Cells transfected with Egr-1 and claudin-3 siRNA displayed significant blockage of HDAC inhibitor-induced anti-invasive activity. Collectively, these findings indicate that the up-regulation of Egr-1 and claudin-3 are crucial steps in HDAC inhibitor-induced anti-metastasis and anti-invasion.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.576-583
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• 2018

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.205-212
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• 2001

One of the important characteristics of biological systems os their ability to change im-portant properties in response to small environmental signals. The molecular mechanisms that biological molecules utilize to sense and respond provide interesting models for the development of "smart" polymeric biomaterials with biomimetic properties. An important example of this is the protein coat of viruses, which contains peptide units that facilitate the trafficking of the virus into the cell via endocytosis, then out of the endosome into the cytoplasm, and from there into the nucleus, We have designed a family of synthetic polymers whose compositions have been de-signed to mimic specific peptides on viral coats that facilitate endosomal escape. Our biomimetic polymers are responsive to the lowered pH whinin endosomes, leading to distruption of the en-dosomal membrane and release of important biomolecular druges such as DNA, RNA, peptides and proteins to the cytoplasm before they are trafficked to lysosomes and degraded by lysosomal en-zymes. In this article, we review our work on the design, synthesis and action of such smart, pH-sensitive polymers.

• BMB Reports
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• v.34 no.2
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• pp.176-181
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• 2001

Using a retrovirus, foreign genes can be introduced into mammalian cells. The purpose of this study is to produce a retrovirus that can make the infected cells express two genes; the human multidrug resistance gene (MDR1) and the HLA-B7 gene, which is one of the major human histocompatibility complex (MHC) class I genes. For the expression of these genes, the internal ribosome entry site (IRES) was used, which was derived from the encephalomyocarditis (EMC) virus. In order to produce retroviruses, a retroviral vector was transfected into a packaging cell line and the transfected cells were treated with vincristine, which is an anti-cancer drug and a substrate for the MDRI gene product. This study revealed that two genes were incorporated into chromosomes of selected cells and expressed in the same cells. The production of the retrovirus was confirmed by the reverse transcription (RT)-PCR of the viral RNA. The retrovirus that was produced infected mouse fibroblast cells as well as the human U937. This study showed that packaging cells produced the retroviruses, which can infect the target cells. Once the conditions for the high infectivity of retrovirus into human cells are optimized, thus virus will be used to infect hematopoietic stem cells to co-express MDRl and HLA-B7 genes, and develop the lymphocytes that can be used for the immnogene therapy.

• The Journal of Korean Medicine
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• v.25 no.2
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• pp.127-137
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• 2004

Objectives : The purpose of this investigation was to evaluate the effects of Sohaphyang-won (SH) on the alteration in gene expression in a hypoxia model using cultured rat cortical cells. Methods : E18 rat cortical cells were grown in neurobasal medium containing B27 supplement. On 12 DIV, SH was added ($20\mu\textrm{g}/ml$) to the culture media for 24 hrs. On 14 DIV, cells were given a hypoxic insult (2% O2/5% CO2, $37^{\circ}C$, 3 hrs), returned to normoxia and cultured for another 24 hrs. Total RNA was prepared from SH-untreated (control) and -treated cultures and alteration in gene expression was analyzed by microarray using rat 5K-TwinChips. Results : Effects on some of the genes whose functions are implicated in neural viability are as follows: 1) For most of the genes altered in expression, the global M values were between -05 to +0.5, Among these, 1517 genes were increased in their expression by more than global M +0.1, while 1480 genes were decreased by more than global M -0.1. 2) The expression of apoptosis-related genes such as Bad (global M =0.35), tumor protein p53 (T53) (global M =0.28) were increased, while v-akt murine thymoma viral oncogene homolog 1 (Akt1) was decreased. 3) The expression of hemoglobin alpha 1 (probably neuroglobin) was increased by about 3.2-fold (global M =1.7). 4) The expression of antioxidation-related catalase gene was increased (global M =0.26). 5) The expression of PKCzeta (prkcz), an upstream kinase of MAPK, was increased (global M =0.29). 6) The expression of retinoic acid receptor alpha (RAR), which may regulate transcription in hypoxic stress, was increased (global M =10.27). Conclusions : In summary, the microarray data suggest that SH doesn't increase the expression of oxygen capture-, anti-oxidation- and 'response to stress' -related genes but decreases some anti-apoptosis genes which would help protect the hypoxic cells from apoptosis.

• Research in Plant Disease
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• v.21 no.4
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• pp.321-325
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• 2015

A rapid and simple RT-PCR diagnosis method for detection of Rice stripe virus (RSV), one of major virus infecting rice, was developed using porous ceramic cubes in this study. The porous ceramic cube can rapidly absorb biological molecules such as small-sized proteins and nucleic acid fragments into its pores. We examined whether this ability of porous ceramic cubes could be applied for isolating viral nucleic acids or particles from the RSV- infected plant tissues. In this study, we found that the porous ceramic cube was capable of absorbing a detection level of viruses from the rice tissues infected with RSV and established RT-PCR-based RNA diagnosis method using porous ceramic cubes.