• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.78.1-78
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• 2003

An osmotin-like protein (CAOSMl) gene was isolated from pepper leaves infected with the avirulent strain Bv5-4a of Xmthomonas campestris pv. vesicatoria. The cDNA encodes a polypeptide of 250 amino acids with a molecular mass of 27, 361 Da. Its amino acid sequence is highly homologous to various osmotin-like proteins from other plant species. The CAOSMl gene expression was organ- and tissue-specifically regulated In pepper plants. The CAOSMl mRNA was intensely localized in the endodermis area of root tissue and in the phloem cells of vascular bundles of red fruit tissue, but not in leaf, stem, and green fruit tissues of healthy pepper plants. Infection by X. c. pv vesintoria, Colletotrichum coccodes, or Phytopkhora capsici iinduced CAOSMl transcription in the leaf or stem tissues. Expression of the CAOSMl gene was somewhat higher in the incompatible than the compatible interactions of pathogens with pepper. The CAOSMl mRNA was prevalently localized in the phloem cells of the vascular bundle of leaf tissues infected by C. coccodes. The CAOSMl gene was activated in leaf tissues by treatment with ethylene, methyl jasmonate, high salinity, cold acclimation and mechanical wounding, but not by abscisic acid (ABA) and drought. These results indicate that the pepper CAOSMl protein functions in response to Pathogens and some abiotic stresses in pepper plants

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.292-299
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• 1993

Agrobacterium tumefaciens KU12 isolated from Korea is able to induce tumors on various plants and catabolize octopine as a sole carbon and nitrogen source. A, tumefaciens KU12 contains three plasmids. Their sizes are 45.5 kb. 240 kb. and > 240 kb. respectively. For the purpose of identification of octopine type Ti plasmid, avirulent A, tumefacients A136 is transformed with plasmids isolated from KU12 by direct transformation. Transformants containing Ti plasmid were grown on AB medium containing octopine as a sole nitrogen source. The isolated strain, named KU911, contains only 240 kb plasmid. As a result of induction of crown gall and Southern hybridization with other octopine Ti plasmid pTiAch5, 240 kb plasmid named pTiKU12 was Ti plasmid.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.237-246
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• 2005

Background: Little information is available on the identification and characterization of the upstream regulators of the signal transduction cascades for Mycobacterium tuberculosis (M. tbc)-induced ERK 1/2 activation and chemokine expression. We investigated the signaling mechanisms involved in expression of CCL3 /MIP-1 and CCL4/MIP-1 in human primary monocytes infected with M. tbc. Methods: MAP kinase phosphorylation was determined using western blot analysis with specific primary antibodies (ERK 1/2, and phospho-ERK1/2), and the upstream signaling pathways were further investigated using specific inhibitors. Results: An avirulent strain, M. tbc H37Ra, induced greater and more sustained ERK 1/2 phosphorylation, and higher CCL3 and CCL4 production, than did M. tbc H37Rv. Specific inhibitors for mitogen-activated protein kinase (MAPK) kinase (MEK; U0126 and PD98059) significantly inhibited the expression of CCL3 and CCL4 in human monocytes. Mycobactetia-mediated expression of CCL3 and CCL4 was not inhibited by the Ras inhibitor manumycin A or the Raf-1 inhibitor GW 5074. On the other hand, phospholipase C (PLC) inhibitor (U73122) and protein kinase C (PKC)specific inhibitors ($G\ddot{o}6976$ and Ro31-8220) significantly reduced M. tbc-induced activation of ERK 1/2 and chemokine synthesis. Conclusion: These results are the first to demonstrate that the PLC-PKC-MEK-ERK, not the Ras-Raf-MEK-ERK, pathway is the major signaling pathway inducing M. tbc-mediated CCL3 and CCL4 expression in human primary monocytes.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.729-741
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• 1997

Background : We have recently reported that airway epithelial cells can produce RANTES and IL-8 in response to the stimulation of tubercle bacilli suggesting a certain role of airway epithelial cells in the pathogenesis of pulmonary tuberculosis. The pathogenesis of tuberculosis is determined by several factors including phagocytosis, immunological response of host, and virulence of tubercle bacilli. Interestingly, there have been reports suggesting that difference in immunological response of host according to the virulence of tubercle bacilli may be related with the pathogenesis of tuberculosis. We, therefore, studied the expressions and productions of RANTES and IL-8 in airway epithelial cells in response to tubercle bacilli(H37Rv, virulent strain and H37Ra, avirulent strain), in order to elucidate the possible pathophysiology of pulmonary tuberculosis. Methods : Peripheral blood monocytes were isolated from normal volunteers. Peripheral blood monocytes (PBM) were stimulated with LPS($10{\mu}g/ml$), H37Rv, or H37Ra($5{\times}10^5$ bacilli/well) along with normal control for 24 hours. A549 cells were stimulated with supernatants of cultured PBM for 24 hours. ELISA kit was used for the measurement of $TNF{\alpha}$ and IL-$1{\beta}$ production in supernatants of cultured PBM and for the measurement of RANTES and IL-8 in supernatants of cultured A549 cells. Northern blot analysis was used for the measurement of RANTES and IL-8 mRNA expression in cultured A549 cells. Results : $TNF{\alpha}$ and IL-$1{\beta}$ productions were increased in cultured PBM stimulated with LPS or tubercle bacilli(H37Rv or H37Ra) compared with the control. There was, however, no difference in $TNF{\alpha}$ and IL-$1{\beta}$ production between cultured PBM stimulated with H37Rv and H37Ra. RANTES and IL-8 expressions and productions were also increased in cultured A549 cells stimulated with LPS or tubercle bacilli compared with the control. RANTES and IL-8 mRNA expressions were significantly increased in cultured A549 cells stimulated with H37Ra-conditioned media(CM) compared with A549 cells stimulated with H37Rv-CM (p<0.05). However, there was no difference in RANTES and IL-8 productions between A549 cells stimulated with H37Rv-CM and H37Ra-CM. Conclusion : Airway epithelial cells can produce the potent chemokines such as RANTES and IL-8, in response to the stimulation of tubercle bacilli. These results suggest that airway epithelial cells may play a certain role in the pathogenesis of pulmonary tuberculosis. However, the role of airway epithelial cells in the pathogenesis of tuberculosis according to the virulence of tubercle bacilli was not clear in this study.