• Applied Microscopy
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• 제18권2호
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• pp.141-152
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• 1988

The developmental processes of the protein body are studied on endosperm cells of Panax ginseng during seed maturation periods. The spherosome, mitochondria, rough endoplasmic reticulum, and ribosome are observed and then are gradually increased in early endosperm cells. Protein body developed from vesicles produced by the rough endoplasmic reticulum and was formed at the enlarged ends of rough endoplasmic reticulum. Also, vacuole-like protein body was observed in associated with rough endoplasmic reticulum. Golgi complex is observed in associated with vacuole and its vesicles containing proteinaceous granules moved and accumulated to the vacuole. Proteinaceous granules are deposited in the spherical or oval shaped vacuole and gradually, vacuole is surrounded by the multi-membranous structure. Rough endoplasmic reticulum, ribosome, Golgi complex, and vacuole are observed in associated with protein body formation.

• BMB Reports
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• 제33권6호
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• pp.448-453
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• 2000

In yeast the key gluconeogenic enzyme, fructose-1,6-bisphosphatase (FBPase), is selectively targeted from the cytosol to the lysosome (vacuole) for degradation when glucose starved cells are replenished with glucose. The pathway for glucose induced FBPase degradation is unknown. To identify the receptor-mediated degradation pathway of FBPase, we investigated the presence of the FBPase receptor on the vacuolar membrane by cell fractionation experiments and binding assay using vid mutant (vacuolar import and degradation), which is defective in the glucose-induced degradation of FBPase. FBPase sedimented in the pellets from vid24-1 mutant after centrifugation at $15,000{\times}g$ for 15 min, suggesting that FBPase is associated with subcellular structures. Cell fractionation experiments revealed that FBPase is preferentially associated with the vacuole, but not with other organelles in vid24-1. FBPase enriched fractions that cofractionated with the vacuole were sensitive to proteinase K digestion, indicating that FBPase is peripherally associated with the vacuole. We developed an assay for the binding of FBPase to the vacuole. The assay revealed that FBPase bound to the vacuole with a Kd of $2.3{\times}10^6M$. The binding was saturable and specific. These results suggest that a receptor for FBPase degradation exists on the vacuolar membrane. It implies the existence of the receptor-mediated degradation pathway of FBPase by the lysosome.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1835-1842
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• 2020

Ergosterol, an essential constituent of membrane lipids of yeast, is distributed in both the cell membrane and intracellular endomembrane components such as vacuoles. Honokiol, a major polyphenol isolated from Magnolia officinalis, has been shown to inhibit the growth of Candida albicans. Here, we assessed the effect of honokiol on ergosterol biosynthesis and vacuole function in C. albicans. Honokiol could decrease the ergosterol content and upregulate the expression of genes related with the ergosterol biosynthesis pathway. The exogenous supply of ergosterol attenuated the toxicity of honokiol against C. albicans. Honokiol treatment could induce cytosolic acidification by blocking the activity of the plasma membrane Pma1p H+-ATPase. Furthermore, honokiol caused abnormalities in vacuole morphology and function. Concomitant ergosterol feeding to some extent restored the vacuolar morphology and the function of acidification in cells treated by honokiol. Honokiol also disrupted the intracellular calcium homeostasis. Amiodarone attenuated the antifungal effects of honokiol against C. albicans, probably due to the activation of the calcineurin signaling pathway which is involved in honokiol tolerance. In conclusion, this study demonstrated that honokiol could inhibit ergosterol biosynthesis and decrease Pma 1p H+-ATPase activity, which resulted in the abnormal pH in vacuole and cytosol.

• Mycobiology
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• 제47권4호
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• pp.457-465
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• 2019

MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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• pp.69-73
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• 1999

In plants as well as in other multicellular organisms, programmed cell death plays essential roles in the abortion or formation of specific cells and tissues during development to organize the plant [11, 15, 18]. A typical example of developmentally programmed cell death in plants is the death during differentiation of tracheary elements which are components of vessels and tracheids, a water-conducting system. The programming of cell death during tracheary element differentiation has been revealed to be unique to plant cells by using the in vitro Zinnia mesophyll cell culture system. In particular, new biosynthesis of autolysis-related enzymes such as cysteine proteases and nucleases, their accumulation of the vacuole and the programmed collapse of the vacuole are essential to the death of tracheary elements and differ greatly from the process of the apoptotic cell death in animals.

• 한국수산과학회지
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• 제45권5호
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• pp.480-485
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• 2012

The hemocytes of the tunicate Halocynthia roretzi are classified into six types based on their size, cellular form, and fine structure of the cytoplasmic granules: hyalinocytes, granulocytes, phagocytes, nephrocytes, morula cells, and multi-vacuole cells. Based on cell size, they are ordered multi-vacuole cells ($7.5{\mu}m$)>nephrocytes ($7.1{\mu}m$)>phagocytes ($6.8{\mu}m$)>granulocytes ($6.1{\mu}m$)>morula cells ($5.7{\mu}m$)>hyalinocytes ($5.4{\mu}m$). The proportion of hemocytes is ranked in the order multi-vacuole cells (54.8%)>nephrocytes (16.9%)>granulocytes (9.9%)>morula cells (8.8%)>phagocytes (6.1%)>hyalinocytes (3.5%).

• Journal of Species Research
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• 제9권4호
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• pp.448-454
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• 2020

Nine free-living heterotrophic flagellates were cultured from marine intertidal sediments and freshwater sediments from Korea. These species are described with uninterpreted records based on light microscopy of living cells and reported taxonomically for the first time from Korea. Diagnostics of these species are as follows; Notosolenus hemicircularis: 9-11.8 ㎛ long with flagellar reservoir, ventrally flattened and dorsally convex with hyaline semicircular collar around short anterior neck, and 8 ridges on cell surface. Thecamonas tranhens: 4.5-7.1 ㎛ long, plastic with proboscis comprising an anterior flagellum surrounded by membranous sleeve. Bodomorpha minima: 4.5-7.0 ㎛ long, rigid with small rostrum in anterior end and active anterior flagellum. Cercomonas hiberna: 5.6-10.9 ㎛ long, very plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Cercomonas pellucida: 7.5-13 ㎛ long, plastic with pseudopodia, cytoplasmic strand and single contractile vacuole. With nucleus closely connected to basal bodies. Eocercomonas echina: 4.7-6.5 ㎛ long, plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas astra: 5.7-7.3 ㎛ long, moderately metabolic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas minima: 5-9 ㎛ long, metabolic with pseudopodia, cytoplasmic strand and single contractile vacuole. Paracercomonas producta: 6.1-9.9 ㎛ long, very metabolic with pseudopodia, long cytoplasmic strand and single contractile vacuole.

• Journal of Ginseng Research
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• 제15권2호
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• pp.131-138
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• 1991

This study was carried out to investigate the development of endoplasmic reticulum and the formation of Protein body in the endosperm cell during seed formation of Panax ginseng C. A. Meyer with electron microscope. In the endosperm cell of early developmental process after pollination, vesicles that contain storage materials produced in rough endoplasmic reticulum incorporated into central vacuole. The central vacuole is gradually subdivided into several small-sized vacuoles and increased in number. Amorphous proteinaceous materials of high electron density are produced in rough endoplasmic reticulum. Rough endoplasmic reticulum increase in number and surround the protein body and vesicles circularly. Spherical proteinaceous granules with limited membrane appeared from the amorphous granules at the peripheral region of the rough endoplasmic reticulum. Gradually, storage materials are accumulated within the vacuole surrounded by spherosomes. Protein bodies are formed by interfusing between vacuoles and vesicles derived from rough endoplasmic reticulum which contained the amorphous protein of high electron density.

• Journal of Species Research
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• 제11권4호
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• pp.278-286
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• 2022

During a field survey of Korean marine ciliates, we collected Pleuronema marinum from a brackish water sample. It is characterized by the presence of a contractile vacuole in mid-body, rather than the subterminal/ terminal contractile vacuole as in other congeners. The cells were examined in vivo and based on protargol and 'wet' silver nitrate impregnation. In addition, the nuclear 18S rRNA gene was sequenced using a single cell. The Korean population morphologically and molecularly resembles a Chinese population of P. marinum. Historical review of the species concludes that 1) two or more species have been assigned into P. marinum, 2) the position of contractile vacuole (e.g., in mid-body) is a valid character state, and 3) P. marinum is probably a rare species. Here we provide a monographic treatment of P. marinum to clarify the issue and for further studies of relevant species. Considering there are about 40 nominal species and complex nomenclatural acts in the genus Pleuronema, further studies should provide descriptions based on protargol and 'wet' silver impregnation with marker gene(s).

• Journal of Plant Biotechnology
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• 제36권1호
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• pp.59-63
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• 2009

작물 스트레스 내성 연구의 궁극적인 과제는 가진 형질을 극대화하여 생산량을 증대하고 외부의 환경적인 요소로부터 피해를 최소화하는 것이다. 따라서 작물의 다양한 외부 환경적 스트레스에 대응하기 위한 연구들이 진행되고 있다. 특히 세포 내 신호전달 과정의 이차매개체인 칼슘에 대한 다양한 연구들이 진행되고 있지만 아직까지 많은 부분이 밝혀져 있지 않다. 본 연구는 모델식물인 애기장대를 이용하여 세포 내 칼슘의 주요 저장소인 액포로 칼슘을 수송하는 역할을 수행하는 $Ca^{2+}$-ATPase의 형질전환 식물을 이용하여 세포 내 칼슘의 신호전달과 식물 생물학적 기능을 알아보았다. ACA11-GFP 유전자가 형질전환된 식물에서 흥미롭게도 ACA11 유전자가 발현 침묵됨으로써 세포 내 칼슘농도 항상성 조절과 신호전달 과정에 문제가 발생하고 세포질 내 활성산소가 증가되어 결국 형질전환체의 잎에서 HR과 같은 세포사멸을 유발한다는 것을 제시하였다.