• Molecules and Cells
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• v.28 no.1
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• pp.57-65
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• 2009

CDC48 is a member of the AAA ATPase superfamily. Yeast CDC48 and its mammalian homolog p97 are implicated in diverse cellular processes, including mitosis, membrane fusion, and ubiquitin-dependent protein degradation. However, the cellular functions of plant CDC48 proteins are largely unknown. In the present study, we performed virus-induced gene silencing (VIGS) screening and found that silencing of a gene encoding a tobacco CDC48 homolog, NgCDC48, resulted in severe abnormalities in leaf and shoot development in tobacco. Furthermore, transgenic tobacco plants (35S:anti-NgCDC48), in which the NgCDC48 gene was suppressed using the antisense RNA method, exhibited severely aberrant development of both vegetative and reproductive organs, resulting in arrested shoot and leaf growth and sterile flowers. Approximately 57-83% of 35S:anti-NgCDC48 plants failed to develop mature organs and died at early stage of development. Scanning electron microscopy showed that both adaxial and abaxial epidermal pavement cells in antisense transgenic leaves were significantly smaller and more numerous than those in wild type leaves. These results indicate that NgCDC48 is critically involved in cell growth and development of tobacco plants. An in vivo targeting experiment revealed that NgCDC48 resides in the endoplasmic reticulum (ER) in tobacco protoplasts. We consider the tantalizing possibility that CDC48-mediated degradation of an as-yet unidentified protein(s) in the ER might be a critical step for cell growth and expansion in tobacco leaves.

• Journal of fish pathology
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• v.22 no.3
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• pp.239-251
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• 2009

The effects of microbiological properties and pathogenicity of Photobacterium damselae subsp. damselae were investigated under different culture conditions, temperature, pH, NaCl and iron concentration on culture media. Favorable conditions for bacterial growth were between 15-30${^{\circ}C}$, pH 5-9, 0-4% NaCl concentration and iron contents of over 10 mM, whereas the bacterial growth was inhibited under iron chelator existence. When P. damselae was cultured in iron-limited tryptic soy broth, total protein concentration of extracellular products, cytotoxic ability of ECPs on cell line, bacterial viability in flounder serum, phospholipase and siderophore activities of ECPs were significantly increased. On the other hand, the activities of P. damselae cultured under iron-added conditions were decreased. In this study, the iron-limited conditions were similar to the host in which iron concentration is low. During infection caused by P. damselae, the conditions could be related to the pathogenesis of the pathogen.

• Natural Product Sciences
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• v.22 no.3
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• pp.147-153
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• 2016

Inflammation plays an important role in host defense against external stimuli such as infection by pathogen, endotoxin or chemical exposure by the production of the inflammatory mediators that produced by macrophage. Anti-inflammatory factor is important to treat the dangers of chronic inflammation associated with chronic disease. This research aims to analyze the anti-inflammatory effects of Garcinia mangostana L. peel extract (GMPE), ${\alpha}$-mangostin, and ${\gamma}$-mangostin in LPS-induced murine macrophage cell line (RAW 264.7) by inhibiting the production of inflammatory mediators. The cytotoxic assay of G. mangostana L. extract, ${\alpha}$-mangostin, and ${\gamma}$-mangostin were performed by MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) to determine the safe and non-toxic concentration in RAW 264.7 for the further assay. The concentration of inflammatory mediators (COX-2, IL-6, and IL-$1{\beta}$) were measured by the ELISA-based assay and NO by the nitrate/nitrite colorimetric assay in treated LPS-induced RAW 264.7 cells. The inhibitory activity was determined by the reducing concentration of inflammatory mediators in treated LPS-induced RAW 264.7 over the untreated cells. This research revealed that GMPE, ${\alpha}$-mangostin, and ${\gamma}$-mangostin possess the anti-inflammatory effect by reducing COX-2, IL-6, IL-$1{\beta}$, and NO production in LPS-induces RAW 264.7 cells.

• The Plant Pathology Journal
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• v.32 no.6
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• pp.519-527
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• 2016

Purple blotch, caused by Alternaria porri (Ellis) Cifferi, is a serious disease incurring heavy yield losses in the bulb and seed crop of onion and garlic worldwide. There is an immediate need for identification of effective resistance sources for use in host resistance breeding. A total of 43 Allium genotypes were screened for purple blotch resistance under field conditions. Allium cepa accession 'CBT-Ac77' and cultivar 'Arka Kalyan' were observed to be highly resistant. In vitro inoculation of a selected set of genotypes with A. porri, revealed that 7 days after inoculation was suitable to observe the disease severity. In vitro screening of 43 genotypes for resistance to A. porri revealed two resistant lines. An additional 14 genotypes showed consistent moderate resistance in the field as well as in vitro evaluations. Among the related Allium species, A. schoenoprasum and A. roylei showed the least disease index and can be used for interspecific hybridization with cultivated onion. Differential reaction analysis of three A. porri isolates (Apo-Chiplima, Apn-Nasik, Apg-Guntur) in 43 genotypes revealed significant variation among the evaluated Allium species (P = 0.001). All together, the present study suggest that, the newly identified resistance sources can be used as potential donors for ongoing purple blotch resistance breeding program in India.

• Journal of fish pathology
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• v.29 no.1
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• pp.13-23
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• 2016

Lectins play significant roles in the innate immune responses through binding to pathogen-associated molecular patterns (PAMPs) on the surfaces of microorganisms. In the present study, tissue distribution and expression analysis of olive flounder lectins were performed after viral hemorrhagic septicemia virus (VHSV) challenge. Fish egg lectin and serum lectin were found to be predominantly expressed in the gills and liver, these results indicate that the transcript expression of olive flounder lectins is concentrated in immune-related tissues. Following a VHSV challenge, an overall increase in the transcript levels of the genes was observed and the expression patterns were distinctly divided into early and later responses during VHSV infection. In conclusion, olive flounder lectins are specifically expressed in immune-related organs and induced in both the immediate and long-lasting immune responses to VHSV in the olive flounder. These results indicate that lectins may be play important roles in the host defense mechanism and involved in the innate and adaptive immune response to viruses in fish.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.254-255
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• 2011

Stem rot symptoms of Euphorbia marginata were occurred in the herb exhibition field at Gyeongsangnam-do Agricultural Research and Extension Services in Korea. The typical symptom was started with watersoaking lesion on the stem then gradually rotted, wilted, and blighted, the severely infected plants were eventually died. The sclerotia of the pathogen were globoid in shape, 1~3mm in size and white to brown in color. The optimum temperature for mycelial growth and sclerotia formation on PDA was $30^{\circ}C$. The hyphal width was 4~9 ${\mu}m$, and the typical clamp connection structures were observed in the hyphae of the fungus grown on PDA. On the basis of mycological characteristics and pathogenicity to host plants, this fungus was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot on E. marginata caused by S. rolfsii in Korea.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.888-897
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• 2014

A bacterial community analysis of the gut of Tenebrio molitor larvae was performed using pyrosequencing of the 16S rRNA gene. A predominance of genus Spiroplasma species in phylum Tenericutes was observed in the gut samples, but there was variation found in the community composition between T. molitor individuals. The gut bacteria community structure was not significantly affected by the presence of antibiotics or by the exposure of T. molitor larvae to a highly diverse soil bacteria community. A negative relationship was identified between bacterial diversity and ampicillin concentration; however, no negative relationship was identified with the addition of kanamycin. Ampicillin treatment resulted in a reduction in the bacterial community size, estimated using the 16S rRNA gene copy number. A detailed phylogenetic analysis indicated that the Spiroplasma-associated sequences originating from the T. molitor larvae were distinct from previously identified Spiroplasma type species, implying the presence of novel Spiroplasma species. Some Spiroplasma species are known to be insect pathogens; however, the T. molitor larvae did not experience any harmful effects arising from the presence of Spiroplasma species, indicating that Spiroplasma in the gut of T. molitor larvae do not act as a pathogen to the host. A comparison with the bacterial communities found in other insects (Apis and Solenopsis) showed that the Spiroplasma species found in this study were specific to T. molitor.

• Journal of Periodontal and Implant Science
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• v.43 no.4
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• pp.191-197
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• 2013

Purpose: Nitric oxide (NO) is a short-lived bioactive molecule that is known to play an important role in the pathogenesis of periodontal disease. In the current study, we investigated the effect of the flavonoid quercetin on the production of NO in murine macrophages activated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen related to inflammatory periodontal disease, and tried to elucidate the underlying mechanisms of action. Methods: LPS was isolated from P. intermedia ATCC 25611 cells by the standard hot phenol-water method. The concentration of NO in cell culture supernatants was determined by measuring the accumulation of nitrite. Inducible NO synthase (iNOS) and heme oxygenase-1 (HO-1) protein expression, phosphorylation of c-Jun N-terminal kinase (JNK) and p38, inhibitory ${\kappa}B$ $(I{\kappa}B)-{\alpha}$ degradation, and signal transducer and activator of transcription 1 (STAT1) phosphorylation were analyzed via immunoblotting. Results: Quercetin significantly attenuated iNOS-derived NO production in RAW246.7 cells activated by P. intermedia LPS. In addition, quercetin induced HO-1 protein expression in cells activated with P. intermedia LPS. Tin protoporphyrin IX (SnPP), a competitive inhibitor of HO-1, abolished the inhibitory effect of quercetin on LPS-induced NO production. Quercetin did not affect the phosphorylation of JNK and p38 induced by P. intermedia LPS. The degradation of $I{\kappa}B-{\alpha}$ induced by P. intermedia LPS was inhibited when the cells were treated with quercetin. Quercetin also inhibited LPS-induced STAT1 signaling. Conclusions: Quercetin significantly inhibits iNOS-derived NO production in murine macrophages activated by P. intermedia LPS via anti-inflammatory HO-1 induction and inhibition of the nuclear factor-${\kappa}B$ and STAT1 signaling pathways. Our study suggests that quercetin may contribute to the modulation of host-destructive responses mediated by NO and appears to have potential as a novel therapeutic agent for treating inflammatory periodontal disease.

• Genomics & Informatics
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• v.3 no.4
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• pp.142-148
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• 2005

The immune response-related genes have been suggested to be the most favorable genes for positive selection during evolution. Comparing the entire DNA sequence of chimpanzee chromosome 22 (PTR22) with human chromosome 21 (HSA21), we have identified 15 orthologs having indel in their coding sequences. Among them, interferon-${\alpha}$ receptor-1 gene (IFNAR1), an immuneresponse-related gene, is subjected to comparative genomic analysis. Chimpanzee IFNAR1 showed the same genomic structure as human IFNAR1 (11 exons and 10 introns) except the 3 bp insertion in exon 4. The sequence alignment of IFNAR1 coding sequence indicated that 'ISPP' amino acid sequence motif is highly conserved in chimpanzee and other animals including mouse and chicken. However, the human IFNAR1 shows that one proline residue is missing in the sequence motif. The homology modeling of the IFNAR1 structures suggests that the proline deletion in human IFNAR1 leads to the formation of the following ${\alpha}$-helix, whereas two sequential prolines in chimpanzee IFNAR1 inhibit it. As a result, human IFNAR1 may adopt a characteristic structure distinct from chimpanzee IFNAR1. This human specific trait could contribute to specific immune response in the most optimized manner for humans. Further molecular biological studies on the IFNAR1 will help us to gain insights into the molecular implication of species-specific host-pathogen interaction in primate evolution.

• Korean Journal of Agricultural Science
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• v.42 no.2
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• pp.99-103
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• 2015

Potato virus T (PVT) is a plant pathogen in the family Betaflexiviridae, group IV single-stranded positive sense RNA viruses. The major host of PVT is potato, and it has been reported in Ullucus tuberosus, Oxalis tuberosa and Tropaeolum tuberosum. This study aimed at developing reverse transcription (RT)-polymerase chain reaction (PCR) and nested PCR techniques for specific detection of PVT. Finally, Two RT-PCR primer sets were developed and verified. The RT-PCR products were amplified to 734 (PVT RT-PCR primer set 6) and 828 bp (PVT RT-PCR primer set 29) long to detect PVT. The nested PCR primer sets [PVT-N70/C20 ($734{\rightarrow}315bp$) and PVT-N75/C30 ($828{\rightarrow}529bp$)] were developed which are high sensitivity and verification for detection of PVT. Furthermore, a modified-positive control plasmid is use to verify contamination of laboratory in PVT detection. This study supported the diagnose PVT in potato or PVT related hosts.