• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.863-870
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• 2010

We investigated geographical condition and soil characteristic of ginseng cultivation site. At all sites, crown density adjusted by 80%. and Air and soil temperature were also measured. The geographical condition vary ato all sites. and soil shows similar characteristics with typical forest soil of Korea. The results shows the Air temperature needs to be higher than $15^{\circ}C$ for seed budding at April When soil temperature reach at 8, leaf of foest ginseng starts to bud. A forest ginseng is influenced by forest type, planting type and budding rates. In the case of a seedling planting, an seeding emergence rate is high, but the rate is decreased rapidly after three years On the other hand, direct seeding shows lower seedling emergence rate, but survival rate is higher than seedling-planting.

• Journal of Microbiology
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• v.39 no.4
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• pp.286-292
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• 2001

During mitosis. the proper segregation of duplicated chromosomes is corrdinated by a spindle check-point. The bifurcated spindle checkpoint blocks cell cycle progression at metaphase by monitoring unattached kinetochores and inhibits mitotic exit in response to the misorientation of the mitotic spin- dle Ibd1p/Bfa1p is a spindle checkpoint regulator of budding yeast in the Bub2p checkpoint pathway for mitotic exit and its disruption abolishes mitotic arrest when proper organization of the mitotic spin-dls inhibited. Ibd1p/Bfa1p localizes to the spindle pole body, a microtublue-organizing center in yeast, and its overexpression arrests the cell cycle in 80% of cells with an enlarged budy at mitosis and in 20 % of cells with multiple buds. In this study, we found that the C-terminus of Ibd1p/Bfa1p phys-ically interacts with Skp1p, a key component of SCF (Skp1/cullin/F-box) complex for ubiquition-medi-ated proteolysis of cel cycle regulatores as well as an evolutionally conserved kinetochore protein for cell cycle progression. A putative F-box motif was found in the C-terminus of Ibd1p/Bfa1p and its function was investigated by making mutants of conserved residues in the motif. These Ibd1p/Bfa1p mutants of a putative F-box interacted with SKp1p in vitro by two-hybrid assays as wild type Ibd1p/Bfa1p. Also these Ibd1p/Bfa1p utants displayed the overexpression phenotypes of wild type Ibd1p, when over-expressed under inducible promoters . These results suggest that a putative F-box motif of Ibd1p/Bfa1p is not essential for the interaction with SKp1p and its function in mitotic exit and cytokinesis.

• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.260-268
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• 1985

An acephalic budding Cysticercus of 1.2 cm long was removed surgically at the abdominal wall of a Korean man. The worm revealed abnormal buds on the bladder wall and absence of suckers and hooklets in the scolex body. The buds were of two histologic types; branching bud covered with normal tegumentum and with subtegumental cells of normal density, and buds of proliferated subtegumental cells with lacunae formation. On the bases of the morphologic features, it was identified as a racemose cysticercus. This case confirms that its extracranial location is possible.

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.231-234
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• 2014

Six unrecorded yeasts, Cryptococcus festucosus 41-3, Cryptococcus heveanensis 56-4, Debaryomyces nepalensis 95-4, Issatchenkia occidentalis 142-1, Dioszegia zsoltii 39-1, and Kwoniella europala 47-2 were screened from 108 yeasts isolated from flowers and fruits in orchards of Yesan-gun, Chungcheongnam-do, Korea. The morphological and cultural characteristics of these unrecorded yeasts were investigated. They had various shapes, including ellipsoidal, globose, and oval, and also had budding mode in vegetable reproduction, except I. occidentalis 142-1 (fission mode). K. europaea 47-2 only formed pseudomycelium. D. zsoliti 39-1 did not grow in yeast extract-malt extract medium, potato dextrose medium, and vitamin-free medium. C. festucosus 41-3 grew well in 5% NaCl-containing yeast extract-peptone-dextrose medium and had a growth pH range of 7.0~10.0. Three unrecorded yeasts Ogataea polymorpha HB45-1, Rhodotonula hinnulla HB62-2, and Cryptococcus rajasthanensis HB80-4 were screened from 51 yeasts isolated from flowers in Hanbat arboretum in Daejeon city, Korea. They were globose in shape and did not form pseudomycelium. In addition, O. polymorpha HB45-1 and C. rajasthanensis HB80-4 had budding mode in vegetable reproduction. All of them grew well in vitamin-free medium and C. rajasthanesis HB80-4 also grew in 50% glucose and 5% NaCl-containing YPD medium.

• Molecules and Cells
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• v.21 no.2
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• pp.251-260
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• 2006

During mitosis, genomic integrity is maintained by the proper coordination of anaphase entry and mitotic exit via mitotic checkpoints. In budding yeast, mitotic exit is controlled by a regulatory cascade called the mitotic exit network (MEN). The MEN is regulated by a small GTPase, Tem1p, which in turn is controlled by a two-component GAP, Bfa1p-Bub2p. Recent results suggested that phosphorylation of Bfa1p by the polorelated kinase Cdc5p is also required for triggering mitotic exit, since it decreases the GAP activity of Bfa1p-Bub2p. However, the dispensability of GEF Lte1p for mitotic exit has raised questions about regulation of the MEN by the GTPase activity of Tem1p. We isolated a Bfa1p mutant, $Bfa1p^{E438K}$, whose overexpression only partially induced anaphase arrest. The molecular and biochemical functions of $Bfa1p^{E438K}$ are similar to those of wild type Bfa1p, except for decreased GAP activity. Interestingly, in $BFA1^{E438K}$ cells, the MEN could be regulated with nearly wild type kinetics at physiological temperature, as well as in response to various checkpoint-activating signals, but the cells were more sensitive to spindle damage than wild type. These results suggest that the GAP activity of Bfa1p-Bub2p is responsible for the mitotic arrest caused by spindle damage and Bfa1p overproduction. In addition, the viability of cdc5-2 ${\Delta}bfa1 $ cells was not reduced by $BFA1^{E438K}$, suggesting that Cdc5p also regulates Bfa1p to activate mitotic exit by other mechanism(s), besides phosphorylation.

• Genomics & Informatics
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• v.7 no.4
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• pp.203-207
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• 2009

The target of rapamycin (TOR) signaling pathway conserved from yeast to human plays critical roles in regulation of eukaryotic cell growth. It has been shown that TOR pathway is involved in several cellular processes, including ribosome biogenesis, nutrient response, autophagy and aging. However, due to the functional diversity of TOR pathway, we do not know yet some key effectors of the pathway. To find unknown effectors of TOR signaling pathway, we took advantage of a green fluorescent protein (GFP)-tagged collection of budding yeast Saccharomyces cerevisiae. We analyzed protein abundance changes by measuring the GFP fluorescence intensity of 4156 GFP-tagged yeast strains under inhibition of TOR pathway. Our proteomic analysis argues that 83 proteins are decreased whereas 32 proteins are increased by treatment of rapamycin, a specific inhibitor of TOR complex 1 (TORC1). We found that, among the 115 proteins that show significant changes in protein abundance under rapamycin treatment, 37 proteins also show expression changes in the mRNA levels by more than 2-fold under the same condition. We suggest that the 115 proteins indentified in this study may be directly or indirectly involved in TOR signaling and can serve as candidates for further investigation of the effectors of TOR pathway.

• Applied Microscopy
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• v.23 no.2
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• pp.97-106
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• 1993

This study was done to elucidate the electron microscopic characteristics of certain pathogenic fungi. Four Candida species, (C. albicans, C. tropicalis, C. parapsilosis and C. glabrate) and Cryptococcus neoformans were cultured for 3 days at $30^{\circ}C$ in the Sabouraud dextrose medium. After incubation, they were stored at $4^{\circ}C$ for 24hours. Fine structures were analyzed by morphometry, and Tukey's HSD test was used for statistics. On scanning electron microscopy C. albicans and C. neoformans were similar in size but different in shape, showing sphero-shape or ovalo-shape in C. neoformans. Surface of C. neoformans was coarse and spiny, but Candida species examined were uniformly smooth. In size, C. glabrata was the smallest among them. Budding scar as seen on the surface of Candida species by the number ranging from 1 to 7. Cryptococcus neoformans showed one or two budding scar. On transmission electron microscopy the cytoplasm of most yeast cells showed plentiful glycogen particles, mitochondria, peroxisomes and vacuoles. However, cell walls were different among four Candida species and Cryptococcus neoformans. The cell wall of Candida species consisted of fibrous layer, that was electron dense layer and transparent layer, in contrast to Cryptococcus neoformans consisted of electron dense layer with lamellar structure. This layer was two times thicker than that of Candida species. The outer layer of cell wall was of radiating pattern.

• Korean Journal of Microbiology
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• v.3 no.1
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• pp.1-6
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• 1965

Over a period of 1962-64, a transmission-experiment of witchess' broom of jujube tree by stem-grafting was conducted. When stem-grafting of sound scions upon diseased roots or diseased scions upon sound roots were carried out, disease transmission of high rate was witnessed; 99% in the former and, in the latter, 62% of the stocks which saw union by callussing and had new shoots. Even when the diseased scions by stem-grafting or the diseased buds by budding upon sound stock died away, the transmission rate was 21% in stem-grafting and 14% in budding which seems to show that, when tissues of diseased plants and stocks are kept contacted over a certain period, the disease transmission occurs. And when the recovered scions taken from once diseased tree were grafted upon diseased roots, the transmission rate was 100 % and therefore it is presumed that the immunity could not be acquired even under the assumption of complete recovery from the disease. In stem-grafting of the diseased scions upon sound roots, 98% of the scions which were stored in the cellar, overwintered and grafted in spring was diseased, whereas the disease rate of the scions which were cut and grafted in spring was only 33%. It was particularly noteworthy that 90% of the scions in the former case and only 3% in the latter case were diseased as of June 18th approximately 2 months after the actual grafting and then the latter advanced to 33% with the passage of time. It appears that the pathogen in branches and shoots of the diseased trees standing outdoors become inactivated or diminished during winter. Through its symptom, pathological change in tissue, and easy transmission of the disease via stem-grafting, it seems certain that the pathogen of the witches broom disease in jujube tree is a virus.

• Molecules and Cells
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• v.39 no.7
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• pp.550-556
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• 2016

During meiosis, exchange of DNA segments occurs between paired homologous chromosomes in order to produce recombinant chromosomes, helping to increase genetic diversity within a species. This genetic exchange process is tightly controlled by the eukaryotic RecA homologs Rad51 and Dmc1, which are involved in strand exchange of meiotic recombination, with Rad51 participating specifically in mitotic recombination. Meiotic recombination requires an interaction between homologous chromosomes to repair programmed double-strand breaks (DSBs). In this study, we investigated the budding yeast meiosis-specific proteins Hop2 and Sae3, which function in the Dmc1-dependent pathway. This pathway mediates the homology searching and strand invasion processes. Mek1 kinase participates in switching meiotic recombination from sister bias to homolog bias after DSB formation. In the absence of Hop2 and Sae3, DSBs were produced normally, but showed defects in the DSB-to-single-end invasion transition mediated by Dmc1 and auxiliary factors, and mutant strains failed to complete proper chromosome segregation. However, in the absence of Mek1 kinase activity, Rad51-dependent recombination progressed via sister bias in the $hop2{\Delta}$ or $sae3{\Delta}$ mutants, even in the presence of Dmc1. Thus, Hop2 and Sae3 actively modulate Dmc1-dependent recombination, effectively progressing homolog bias, a process requiring Mek1 kinase activation.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.141-150
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• 2019

The spatial landmark protein Bud8 plays a crucial role in bipolar budding in the budding yeast Saccharomyces cerevisiae. The unconventional yeast Yarrowia lipolytica can also bud in a bipolar pattern, but is evolutionarily distant from S. cerevisiae. It encodes the protein YALI0F12738p, which shares the highest amino acid sequence homology with S. cerevisiae Bud8, sharing a conserved transmembrane domain at the C-terminus. Therefore, we named it YlBud8. Deletion of YlBud8 in Y. lipolytica causes cellular separation defects, resulting in budded cells remaining linked with one another as cell chains or multiple buds from a single cell, which suggests that YlBud8 may play an important role in cell separation, which is distinct from the function of Bud8 in S. cerevisiae. We also show that the YlBud8-GFP fusion protein is located at the cell membrane and enriched in the bud cortex, which would be consistent with a role in the regulation of cell separation. The coiled-coil domain at the N-terminus of YlBud8 is important to the correct localization and function of YlBud8, as truncated proteins that do not contain the coiled-coil domain cannot rescue the defects observed in $Ylbud8{\Delta}$. This finding suggests that a new signaling pathway controlled by YlBud8 via regulation of cell separation may exist in Y. lipolytica.