• 한국균학회지
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• 제49권1호
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• pp.1-10
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• 2021

A survey of fungal diversity in Gyeongsang Province, Korea, revealed two previously unreported Aspergillus isolates, named KMG411 and KMG412. The phylogeny of the isolates was analyzed based on β-tubulin (BenA) and calmodulin (CaM) sequencing. Morphological analyses further identified the KMG411 and KMG412 as A. insuetus and A. nomius, respectively. Here we provide detailed morphological descriptions of the previously unrecorded Aspergillus species.

• Animal cells and systems
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• 제3권2호
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• pp.207-213
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• 1999

During the differentiation of Naegleria gruberi amoebas into flagellates, the amoebas undergo sequential changes in cell shape and form new cellular organelles. To understand the nature of the signal which initiates this differentiation and the signal transduction pathway, we treated cells with four agents, PMA, retinoic acid (RA), okadaic acid, and cAMP. Retinoic acid and cAMP had specific effects on the differentiation of N. gruberi depending on the time of the drug treatment. Addition of (100$\mu$M) retinoic acid at the initiation of differentiation inhibited differentiation by blockinq the transcription of differentiation specific genes (e.g., $\beta$-tubulin). This inhibition of differentiation by retinoic acid was overcome by co-treatment with cAMP (or dbcAMP, 20 $\mu$M). Addition of retinoic acid at later stages (30 and 70 min) had no effect on the transcriptional regulation of the $\beta$-tubulin gene, however the differentiation was inhibited by different degrees. Co-treatment of cAMP at these stages did not overcome the inhibitory effect of retinoic acid. These results suggest that the role of retinoic acid as a transcriptional regulator might be conserved throughout the evolution of eukaryotes.

• 한국균학회지
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• 제43권1호
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• pp.58-63
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• 2015

진균에 의한 오염은 재배사에서 톱밥 배지를 이용한 표고 재배에 중대한 영향을 미치기 때문에 표고 재배사 실내 공기에 존재하는 진균에 대한 모니터링을 수행하던 중 여러 진균을 분리하였다. 분리된 진균 중에는 국내 미기록인 Aspergillus pulverulentus와 Cosmospora butyri 등 2종을 비롯하여 기록은 있으나 균학적 확증이 부족한 Lecanicillium psalliotae와 L. antillanum 등 2종이 존재하였다. 본 논문에서는 이들 균류에 대한 형태적 특성과 더불어 internal transcribed spacer (ITS) rDNA region 또는 ${\beta}$-tubulin 유전자 염기서열에 기반한 계통학적 분석 결과를 기술하였다.

• 한국균학회지
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• 제43권1호
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• pp.71-76
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• 2015

수생식물 샘플은 낙동강과 금호강이 만나는 달성습지에서 자라풀을 채집하였다. 자라풀의 뿌리에서 내생균류를 분리하고 형태가 다른 균주를 관찰하여 최종적으로 16개 균주를 선발하였다. 내생균류의 배양여과액은 식물생장촉진활성 검정을 위하여 난장이벼에 처리하여 스크리닝하였으며, HD1008 균주가 식물생장촉진활성이 가장 높은 것으로 확인되었다. HD1008 균주의 배양여과액을 HPLC와 GC/MS-SIM을 이용하여 분석하였고, HD1008 균주가 식물호르몬인 지베렐린 $GA_1$ (1.2 ng/100 mL)과 $GA_4$ (5 ng/100 mL) 를 생산하는 것을 정량분석을 통하여 확인하였다. 또한, HD1008균주의 beta-tubulin 유전자 염기서열을 이용하여 동정에 이용하였으며, 분자적인 방법과 형태적인 방법으로 관찰하였을 때, 지베렐린을 생산하는 새로운 P. trzebinskii로 동정되었다.

• Mycobiology
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• 제46권2호
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• pp.101-113
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• 2018

Lichen genus Stereocaulon (Schreb.) Hoffm is distributed throughout the world. Although 15 Stereocaulon species have been recorded in Korea, no detailed taxonomic or revisionary research has been conducted for nearly two decades. In this study, we collected 260 putative Stereocaulon spp. samples and identified the species based on morphological, chemical, and molecular characteristics. From the collected samples, 10 species of Stereocaulon were identified, nine of which had already been reported, although this was the first report for the tenth, S. octomerellum Hue, in Korea. General characteristics of Stereocaulon spp. include coralloid phyllocladia and tubercular cephalodia; however, the specimen first collected in Korea was a rare species with tomentum on the pseudopodetia. The specimen of S. octomerellum is characterized by the presence of a primary thallus, granule to short coralloid phyllocladia, and pseudopodetia up to 1 cm in size, with tubercular cephalodia. To determine the phylogeny of the specimens, we compared the ITS sequences of ribosomal DNA and the b-tubulin gene sequences. Phylogenetic analysis showed that the Korean Stereocaulon species were monophyletic and placed in the previous phylogenetic classification. Species of S. intermedium and S. exutum, however, were polyphyletic, and are morphologically variable and widespread species. Overall, we present here detailed morphological and chemical descriptions of each species identified and a revised key of all known Stereocaulon species in South Korea.

• The Plant Pathology Journal
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• 제33권2호
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• pp.140-147
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• 2017

Fusarium wilts of strawberry, caused by Fusarium oxysporum f. sp. fragariae, is a serious soil-borne disease. Fusarium wilt causes dramatic yield losses in commercial strawberry production and it is a very stubborn disease to control. Reliable chemical control of strawberry Fusarium wilt disease is not yet available. Moreover, other well-known F. oxysporum have different genetic information from F. oxysporum f. sp. fragariae. This analysis investigates the genetic diversity of strawberry Fusairum wilt pathogen. In total, 110 pathogens were isolated from three major strawberry production regions, namely Sukok, Hadong, Sancheong in Gyeongnam province in South Korea. The isolates were confirmed using F. oxysporum f. sp. fragariae species-specific primer sets. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses were executed using the internal transcribed spacer, intergenic spacer, translation elongation factor1-${\alpha}$, and ${\beta}$-tubulin genes of the pathogens and four restriction enzymes: AluI, HhaI, HinP1I and HpyCH4V. Regarding results, there were diverse patterns in the three gene regions except for the ${\beta}$-tubulin gene region. Correlation analysis of strawberry cultivation region, cultivation method, variety, and phenotype of isolated pathogen, confirmed that genetic diversity depended on the classification of the cultivated region.

• The Plant Pathology Journal
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• 제26권1호
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• pp.49-56
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• 2010

Thirty-six isolates of Colletotrichum spp. were obtained from infected grapes in two different locations of Korea; 18 isolates from Cheonahn, where carbendazim (MBC) and the mixture of MBC and diethofencarb (NPC) had been applied to control grape ripe rot, and 18 isolates from Cheongju, where no fungicides had been used. Sequences analysis of the internal transcribed spacer (ITS) and the $\beta$-tubulin gene identified 34 of the 36 isolates as Colletotrichum gloeosporioides. The remaining two isolates from Cheongju were identified as C. acutatum. Of the 18 isolates from Cheonahn, 12 were resistant to both MBC and the mixture (MBC+NPC), and six were sensitive to them. All C. gloeosporioides isolates from Cheongju, but not the two C. acutatum isolates, were sensitive to these fungicides. Sequence analysis of the $\beta$-tubulin gene in all isolates revealed that C. gloeosporioides resistant to MBC and MBC+NPC had a tyrosine instead of phenylalanine at the amino acid position 200. The appearance of resistance to MBC and the mixture in C. gloeosporioides correlated with the history of fungicide application in Korea.

• Journal of Applied Biological Chemistry
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• 제51권1호
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• pp.1-6
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• 2008

Estrogens, a group of steroid compounds functioning as the primary female sex hormone, play an important role in the development and progression of breast cancer. In this study, using a novel annealing control primer-based GeneFishing PCR technology, five differentially expressed genes (DEGs), expressed using 10nM mitogenic estrogens, $17{\beta}$-estradiol (E2) and $16{\alpha}$-hydroxyestrone ($16{\alpha}$-OHE1), were selected from the estrogen receptor (ER)-positive MCF-7 human breast cancer cells. The DEGs, MRPL42, TUBA1B, SSBP1, KNCT2, and RUVBL1, were identified by comparison with the known genes via direct sequencing and sequence homology search in BLAST. Quantitative real-time PCR data showed that two DEGs, tubulin ${\alpha}1b$ and kinetochore associated 2, were greater than 2-fold upregulated by E2 or $16{\alpha}$-OHE1. Both genes could be new biomarkers for the treatment and prognosis of cancers, and further study may provide insights into the molecular mechanisms underlying development and progression of breast cancer.

• Reproductive and Developmental Biology
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• 제33권1호
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• pp.7-11
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• 2009

This study was performed to confirm the microtubule assemblies and methylation patterns of porcine IVF and parthenogenetic embryos. Cumulus-oocyte complexes were collected and matured in vitro for 42 hr. Oocytes were fertilized by prepared fresh sperm or activated parthenogenetically by exposure to electric stimulation and 6-dimethylaminopurine. Porcine IVF and parthenogenetic embryos were cultured in vitro for 6 days. Embryos were stained by immunofluorescence staining method to observe the dynamic of nucleus and microtubules in the first mitotic phase and the methylation patterns in different developmental stages. After then, samples were confirmed and analyzed through a laser-scanning confocal microscope. IVF embryos had a centrosome originated from sperms, which was shown a $\gamma$-tubulin spot. However, $\gamma$-tubulin spot was not observed in parthenogenetic embryos. A lower methylation level was observed in IVF embryos compared to parthenogenetic ones at the morula and blastocyst stages. In conclusion, it is considered that microtubule assemblies and genetic regulation mechanism differ between parthenogenetic and IVF embryos.

• 한국균학회지
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• 제45권4호
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• pp.292-303
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• 2017

2016년 버섯 재배사 내 실내공기, 식물병반(동백나무의 잎, 줄딸기, 은방울꽃, 생강나무), 버섯 배양배지 재료, 오염된 가구 등에서 진균을 분리 동정하였다. 동정된 진균 중 18종이 국내 미기록임을 확인하였다. 동정된 진균은 버섯 재배사 내 실내공기에서 6종, 식물병반에서 6종, 버섯 배양배지 재료에서 5종, 오염된 가구에서 1종이 각각 분리되었다 이들 동정된 균주에 대한 형태학적 특성과 ITS rDNA, 18S rDNA, 28S rDNA, calmodulin gene, translation elongation factor gene, ${\beta}-tubulin$ gene 등의 염기서열에 기반한 분자계통학적 관계에 대하여 기술하였다.