• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.84.1-84
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• 2003

Magnaporthe grisea, the casual agent of rice blast, forms an appressorium to penetrate its host. Much has been learned about environmental cues and signal transduction pathways, especially those involving CAMP and MAP kinases, on appressorium formation during the last decade. More recently, pharmacological data suggest that calcium/calmodulin-dependent signaling system is involved in its appressorium formation. To determine the role of phosphoinositide-specific phospholipase C (PI-PLC) on appressorium formation, a gene (WPLCl) encoding PI-PLC was cloned and characterized from M. grisea strain 70-15. Sequence analysis showed that MPLCl has alt five conserved domains present in other phospholipase C genes from several filamentous fungi and mammals. Null mutants (mplcl) generated by targeted gene disruption exhibited pleiotropic effects on conidial morphology, appressorium formation, fertility and pathogenicity. mplcl mutants developed nonfunctional appressoria and are also defective in infectious growth in host tissues. Defects in appressorium formation and pathogenicity in mplcl mutants were complemented by a mouse PLCdelta-1 cDNA under the control of the MPLCl promoter. These results suggest that cellular signaling mediated by MPLCl plays crucial and diverse roles in development and pathogenicity of M. grisea, and functional conservation between fungal and mammalian Pl-PLCs.

• 한국식물병리학회지
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• 제14권6호
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• pp.571-577
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• 1998

Variability in virulence of Calonectria ilicicola isolates form different hosts and geographic origin provides important information for breeding cultivars resistant to red crown rot. A wide range in virulence for 25 isolates of C. ilicicola from soybean and peanut was observed on six soybean cultivars. Soybean isolates were pathogenic on soybean although some were less virulent. Virulence of isolates was not affected greatly by cultivar and relatively consistent regardless of virulence level. Soybean isolates were more virulent on soybean than were peanut isolates. When virulence of two soybean and tow peanut isolates was compared between laboratory and greenhouse tests, it was stable across a range of cultivars. Mycelial growth of isolates from either soybean or peanut was reduced significantly on potato dextrose chlorate showed significant reduction of fungal growth than isolates from peanut did although their growth on potato dextrose agar was not significantly different. Evidence for physiologic specialization was not recognized in this system. However, the findings that soybean isolates of C. ilicicola were more virulent on soybean and reduction of fungal growth on potato dextrose chlorate than were peanut isolates suggest that host specialization may exist in this fugus.

• Mycobiology
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• 제35권3호
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• pp.159-161
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• 2007

Pine tree death caused by pine wood nematode(PWN) involves phoretic relationships between PWN and its vector Japanese pine sawyer beetle(JPS). In an effort to understand the diversity of fungi involved in PWN life cycle, a total of 176 fungal isolates were collected from PWNs, adults and larvae of JPS, PWN-diseased Japanese black pine that was cut down in 2005 at Jinju, Korea. Based on microscopic observation and colony morphology, and sequence analysis of the ITS rDNA, the fungal isolates were identified at the level of genus. Three genera including Mucor, Ophiostoma, and Penicillium were identified from PWN. Two genera of Ophiostoma and Penicillium were discovered from JPS larvae. Frpm JPS adult beetles, nine genera of Aspergillus, Gibberalla, Hypocrea, Irpex, Leptosphaeria, Ophiostoma, Penicillium, and Plectosphaerella and unknown basidio-mycetes were found. Ten genera from PWN-infected weed were confirmed as Bionectria, Botrytis, Camarops, Fusarium, Hypocrea, Nectria, Mucor, Ophiostoma, Penicillium, and Trichoderma. Penicillium and Ophiostoma were commonly distributed on PWN and its vector and host. This is first report of the fungi associated with PWN and its vector and host in Korea.

• 한국균학회지
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• 제46권4호
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• pp.427-435
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• 2018

본 연구에서는 충남, 제주, 경남, 충북 등에서 새우난초(Calanthe discolor)와 은대난초(Cephalanthera longibracteata)의 뿌리를 채취하여 표면살균한 후 내생균을 순수분리 하였다. 분리된 내생균의 형태학 특징을 관찰하고 internaltranscribed spacer (ITS) rDNA영역의 염기서열을 ITS1F와 ITS4프라이머를 이용하여 분석하였다. 서로 다른 지역에서 채집한 새우난초와 은대난초이지만, 공통적으로 Leptodontidium orchidcola가 높은 상대수도와 빈도를 나타냈으며, 내생균류의 군집차이를 분석할 결과, 지역적 차이보다는 숙주에 의한 차이가 더 큰 영향을 미치는 것으로 나타났다.

• Journal of Chest Surgery
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• 제37권12호
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• pp.1022-1024
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• 2004

국균은 사람에서 발견되는 진균중 가장 흔한 것이기는 하나 낮은 병원성을 갖고 있다. 국균의 호흡기 감염은 국균종, 기관지폐 국균증,괴사성 및 침습형 폐 국균증의 유형으로 분류된다. 이중 괴사성 및 침습형 폐 국균증은 장기 이식 후 면역억제 치료를 받고 있거나, 항암요법을 받는 자, 혈액 이상자 또는 후천성 면역 결핍증 환자 같이 면역 저하자에서 주로 발생하며 정상적인 면역 능력이 있는 자에서는 발병률이 매우 낮다. 본원에서는 정상 면역 능력을 갖은 자에서 흉추에 침범한 침습형 페 국균증을 1예 치험하였기에 보고하는 바이다.

• The Plant Pathology Journal
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• 제36권1호
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• pp.98-105
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• 2020

Venturia nashicola is a fungal pathogen causing scab disease in Asian pears. It is particularly important in the Northeast Asia region where Asian pears are intensively grown. Venturia nashicola causes disease in Asian pear but not in European pear. Due to the highly restricted host range of Venturia nashicola, it is hypothesized that the small secreted proteins deployed by the pathogen are responsible for the host determination. Here we report the whole genome based phylogenetic analysis and predicted secretomes for V. nashicola isolates. We believe that our data will provide a valuable information for further validation and functional characterization of host determinants in V. nashicola.

• IMMUNE NETWORK
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• 제16권3호
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• pp.159-164
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• 2016

IL-33 is a multifunctional cytokine that is released in response to a variety of intrinsic and extrinsic stimuli. The role of IL-33 in Candida albicans infections is just beginning to be revealed. This cytokine has beneficial effects on host defense against systemic C. albicans infections, and it promotes resistance mechanisms by which the immune system eliminates the invading fungal pathogens; and it also elevates host tolerance by reducing the inflammatory response and thereby, potentially, tissue damage. Thus, IL-33 is classified as a cytokine that has evolved functionally to protect the host from damage by pathogens and immunopathology.

• ALGAE
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• 제20권4호
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• pp.363-368
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• 2005

The brown alga Ascophyllum nodosum and its mutualistic, ascomycete symbiont, Mycophycias ascophylli, form a complex ‘rganism’or symbiotum. Here we show the interaction of the symbiotum to the abundant brown algal epiphyte, Elachista fucicola. Microscopy of field-collected plants shows morphological responses of A. nodosum to the common epiphyte E. fucicola. When E. fucicola attaches to A. nodosum a bundle of several to dozens of rhizoids penetrates into the host. On the surface of the host, the cells proliferate to form a donut-shaped ring, 100-200 μm in height that surrounds the thallus of E. fucicola. A pit forms in advance of the rhizoids and the cells of A. nodosum break down. This leaves the network of fungal hyphae partially intact and intermingling with the epiphyte rhizoids and its lowermost cells. After the pit is formed, the cells of A. nodosum bordering the infection chamber redifferentiate an epidermal layer. Neither the host nor its mutualistic fungus, M. ascophylli appears to recognize E. fucicola as an invader and to prevent the attachment and growth of this epiphyte. Based on the physical damage to the host caused by invading rhizoids, we conclude that the relationship of E. fucicola to A. nodosum is that of a parasite and its host.

• The Plant Pathology Journal
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• 제35권2호
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• pp.91-99
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• 2019

Mitogen-activated protein kinase (MAPK) cascades in fungi are ubiquitously conserved signaling pathways that regulate stress responses, vegetative growth, pathogenicity, and many other developmental processes. Previously, we reported that the AbSte7 gene, which encodes a mitogen-activated protein kinase kinase (MAPKK) in Alternaria brassicicola, plays a central role in pathogenicity against host cabbage plants. In this research, we further characterized the role of AbSte7 in the pathogenicity of this fungus using ${\Delta}AbSte7$ mutants. Disruption of the AbSte7 gene of A. brassicicola reduced accumulation of metabolites toxic to the host plant in liquid culture media. The ${\Delta}AbSte7$ mutants could not efficiently detoxify cruciferous phytoalexin brassinin, possibly due to reduced expression of the brassinin hydrolase gene involved in detoxifying brassinin. Disruption of the AbSte7 gene also severely impaired fungal detoxification of reactive oxygen species. AbSte7 gene disruption reduced the enzymatic activity of cell walldegrading enzymes, including cellulase, ${\beta}$-glucosidase, pectin methylesterase, polymethyl-galacturonase, and polygalacturonic acid transeliminase, during host plant infection. Altogether, the data strongly suggest the MAPKK gene AbSte7 plays a pivotal role in A. brassicicola during host infection by regulating multiple steps, and thus increasing pathogenicity and inhibiting host defenses.

• 한국균학회지
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• 제15권1호
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• pp.48-69
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• 1987

외생균근(外生菌根)버섯의 기주범위(寄主範圍)와 기주선택성(寄主選擇注)을 구명(究明)하고 주요(主要) 조림수종(造林樹種)의 균근균(菌根菌) 선택성(選擇性)을 상호비교(相互比較)하기 위하여 1981년(年)부터 1986년(年)까지 전국(全國)의 여러 곳에서 12개수종(個樹種)의 순림(純林)(소나무, 리기다소나무, 잣나무, 종비나무, 일본잎갈나무, 젓나무, 현사시, 밤나무, 갈참나무, 상수리나무, 신갈나무, 자작나무)를 대상(對象)으로 균근(菌根)버섯을 채집(採集)하여 분석(分析)을 비교(比較)하였다. 6년(年)동안 총(總) 48리(履) 196종(種) 8 품종(品種)의 균근(菌根) 버섯을 동정(同定)하였으며 그 중 Russla가 31종(種) 1 품종(品種), Amanita가 22종(種) 5 품종(品種), Lactarius가 18종(種) 1 품종(品種)이었다. 기주범위(寄主範圍)가 넓은 종(種)은 Russula, Amanita, Lactarius, Laccaria, Cantharellus 속(屬)에 속(屬)해 있있다. Laccaria Laccata는 12개조사수종중(個調査樹種中)에서 12개수종전분의 임분(林分)에서, Amanita vaginata group은 11개수종(個樹種)에서, Labtarius gerardii와 Russula sororia는 9 개수종(個樹種)에 서, Amanita agglutinata, Cantharellus cibarius, Russula bella, Russula bella, Russula virescens는 8개수종(個樹種)의 침개엽수임분(針開葉樹林分)에서 채집(採集)되어 기주(寄主)의 범위(範圍)가 넓은 버섯으로 분류(分類)되었다. Amanita citrina, Boletus bicolor, Boletus erythropus, Lactarius piperatus, L. subzonarius, Russula pseudodelica는 침개활수(針葉闊樹)의 $4{\sim}5$개수종(個樹種)에서 채집(採集)되어 기주(寄主)의 범위(範圍)가 중간(中間)정도(程度)인 버섯으로 분류(分類)되었으며 특히 Suillus grevillei는 잎갈나무에서서만 채집(採集)되어 기주(寄主)의 범위(範圍)가 가장 좁은 버섯으로 판명(判明)되었다. 12개수종(個樹種)의 임분중(林分中)에서 균근(菌根)버섯의 종류(種類)가 가장 많은 젓나무림(林)으로써 83종(重)의 균근(菌根)버섯을 채집(採集)했으며, 소나무(赤松)림(林)에서 66종(重)을, 리기다소나무림(林)에서 50종(種)을, 잣나무림(林)에서 49종(重)을, 갈참나무림(林)에서 46종(種)을 채집(採集)했다. 일본잎갈나무림(林)에서는 23종(種)의 균근(菌根)버섯을 채집(採集)했는데 다른 임분(林分)과 달리 Amanita, Lactarius, Russula 는 적고 대신 Laccaria 가 많이 관찰(觀察)되었다. 본(本) 실험(實驗)에서 조사(調査)된 12개수종(個樹種)의 대부분(大部分)은 다양(多樣)한 균근(菌根)버섯과 공생(共生)하는 듯하며 균선택성(菌選擇性)이 적은 것으로 사료(思料)된다.