• Journal of Plant Biology
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• v.31 no.2
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• pp.91-100
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• 1988

The effect of Ca2+ and polyamines on the activity $\beta$-glucan synthetase II(GSII) related to cell wall synthesis was studied in carrot suspension cultured cells. The activity of GS II is four times higher than that of $\beta$-glucan synthetase I in carrot suspension cultured cells and in vitro expreiment, the activity of GSII was increased in response to increase in concentration of Ca2+ and polyamines. When carrot suspension cultured cells were incubated together with Ca2+ and polyamines, the GSII activity was high at 0.1mM of Ca2+ and 1mM of putrescine. Also, polycationic poly-L-lysine and poly-L-ornithine increased about 50% the GSII activity than that of the control, respectively. These results may imply that Ca2+ and polyamines were related to the enzyme activity as a polycationic nature. In addition, verapamil as the calcium channel blocker and flunarizine as an antagonist of calcium mechanism in cytoplasm decreased GSII activity ramarkably, Ca2+ and calmodulin stimulated GSII activity as Ca2+ of free ion rather than Ca2+ calmodulin complex. The effect of 2,4-D on the GSII activity in culture medium is shown to be low at 0.1mg per liter and GSII activity increased about 30% more than that of the 0.1mg/l at the range of 0.3-1.0mg per litere. Cummulative results suggest that Ca2+ and polyfamines stimulate the cell wall synthesis by means of the enhancement of GSII activity responsible for synthesizing the cell wall components.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.274-278
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• 1996

토마토 과실의 연화현상의 주 원인으로 판단되는 세포벽의 형태적 변화를 조사하기 위하여 성숙 단계별로 취하여 과실의 경도, 세포벽 구성 성분의 변화 및 세포벽의 변화를 조사하였다. 과육의 경도는 적숙기 이후부터 급셕한 감소를 나타내었다. 세포벽 함량은 성숙 중에 감소하였고 가용성 펙틴의 증가와 불용성 펙틴의 감소는 적숙기와 식용 적기 사이에서 가장 현저했으며, 총 펙텐의 함량은 다소 감소하는 경향을 나타내었다. 성숙에 따른 토마토 과육의 세포 및 세포벽의 형태적 변화를 현미경으로 관찰한 결과, 수확기까지의 토마토에서는 middle lamella와 세포내 기관들이 잘 관찰되었으나, 연화가 진행됨에 따라 식용 적기의 토마토에는 middle lamella를 관찰할 수 없었으며 과숙기 에서는 middle lamella의 가용화와 함께 세포벽의 부분적인 분해와 세포분리현상이 관찰되었다.

• Applied Microscopy
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• v.13 no.1
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• pp.31-40
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• 1983

Ultrathin sections of intact mycelia, released protoplast and fused protoplast of Micromonospora rosaria were observed by electron microscopy Intact mycelia showed a typical gram-positive bacterial cell wall structure and mesosomes. Released protoplasts had no cell wall components and fibrous nuclear region was distinguished from cytoplsmic region clearly. Protoplasts which treated with sucrose supplemented buffer were stable. But those treated with buffer without sucrose were extensively damaged, forming mom braneous vesicles. It was surmised that those vesicles originated from the damaged cytoplasmic membrane. High frequency of fusion was achieved by 50%(w/v). polyethylene-glycol 1,000 Fusion bodies in different stage of fusion were observed. Cell membrane barrier was stepwise relieved.

• Journal of Life Science
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• v.16 no.5
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• pp.834-839
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• 2006

This study was carried out to investigate changes in cell wall components and solubilization and depolymerization of pectin and neutral sugar polymers during softening of 'Tsugaru' apples. Pectic polysaccharides were solubilized in different solvents, distilled-water, 0.05 M CDTA, 0.05 M $Na_2CO_3$, and 8 M KOH, from cell wall materials during fruit softening. The uronic acid contents in distilled-water fraction rapidly increased along with fruit softening at 4 weeks after ambient storage. In the change of non-cellulosic neutral sugars in the cell wall of ‘Tsugaru’ fruits, the major sugar was galactose and arabinose in distilled-water, 0.05 M CDTA and 0.05 M $Na_2CO_3$ soluble fractions, and it was glucose, galactose and xylose in 8 M KOH fraction. Especially the change of galactose contents in distilled-water fraction was increased greatly along with fruit softening. When uronic acid polymers (UAP) and carbohydrate polymers (CP) in distilled-water fraction were filtered and separated using Sepharose CL-2B column, the high molecular UAP and CP were degraded to the low molecular ones from at harvest to softening fruit. Thus, the amount of high molecular polymers were greatly decreased along with fruit softening.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.55-60
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• 2004

Changes of cell wall components and softening enzyme during the preparation of persimmon pickles with soy sauce and soy paste were investigated. The contents of alcohol insoluble substance and cell wall extracted from persimmon pickles in soy sauce and soy paste were gradually decreased to the 20th day of storage and then decreased rapidly, but the contents of water soluble material extracted from persimmon pickles in soy sauce and soy paste was increased during the storage time $(0{\sim}50\;days)$. The contents of lignin, pectin and acid-soluble hemicellulose of persimmon pickles in soy sauce and soy paste were decreased during the storage, but contents of alkali-soluble hemicellulose was increased. The contents of cellulose almost did not change during storage of pickles. The hardness of persimmon pickles in soy sauce and soy paste was gradually increased up to the 30th day of storage and then decreased. The activities of polygalacturonase and pectinesterase as softening enzyme in persimmon pickles with soy sauce and soy paste increased during storage. And ${\beta}-galactosidase$ activity was slightly increased to the 30th day of storage and after increased rapidly.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.226-232
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• 2014

To understand transition characteristics from wood to charcoal the dimensional changes of carbonized woods at low temperature from $300^{\circ}C$ to $350^{\circ}C$ at the intervals of $10^{\circ}C$ were investigated. Three species of hardwoods and two species of softwoods were used in this study. Measurements of dimensional changes of cells were observed by stereoscopic microscope and an image analyzer. The apparent volume of each specimen decreased greatly with increasing temperature. Severe cracks and collapse were observed frequently in hardwoods and hardly in softwoods. Vessel diameter and tracheid cell wall thickness of the wood samples were decreased with increasing carbonization temperature. Contraction of vessel diameter in tangential direction was greater than that in radial direction. Cell wall thickness of tracheids decreased with increasing carbonization temperature. Consequently, even though it was small range of carbonization temperature, dimensions of wood components were changed considerably.

• ALGAE
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• v.23 no.3
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• pp.163-175
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• 2008

Phenolic compounds play a major role in the interaction of plants with their environment. They are thought to have been a feature of higher plants since early colonization of the land. Phenolics are crucial for many important aspects of plant life. They can play structural roles in different supporting or protective tissues, for example in cell walls, they can be involved in defence strategies, and signalling properties particularly in the interactions between plants and their environment. In brown algae, phenolic compounds are contained within membrane bound vesicles known as physodes, and their roles in algae are thought to be similar to those of higher plant phenolics. They can be stained using various histochemical stains, however, none of these stains are phenolic specific so care must be taken during interpretation of such results. Many, but not all phenolics are also autofluorescent under UV or violet light. Physodes are involved in cell wall construction, both in primary and secondary walls in brown algae. They bind together with other wall components to make a tough wall. They have also been found to play a role at fertilization, in blocking polyspermy in some species. Sperm are very quickly rendered immobile after phenolic release from newly fertilized zygotes seconds after fertilization. Phenolic compounds are thought to be important herbivore deterrents in some species due to their astringent nature. Phenolic compounds also offer effective UV protection in the early life stages and also the adults of many algal species. In the future, this factor may also make them an important player in the pharmaceutical and skincare industries.

• Mycobiology
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• v.51 no.3
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• pp.178-185
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• 2023

The cell wall integrity (CWI) signaling pathway plays important roles in the dissemination and infection of several plant pathogenic fungi. However, its roles in the pepper fruit anthracnose fungus Colletotrichum scovillei remain uninvestigated. In this study, the major components of the CWI signaling pathway-CsMCK1 (MAPKKK), CsMKK1 (MAPKK), and CsMPS1 (MAPK)-were functionally characterized in C. scovillei via homology-dependent gene replacement. The ΔCsmck1, DCsmkk1, and ΔCsmps1 mutants showed impairments in fungal growth, conidiation, and tolerance to CWI and salt stresses. Moreover, ΔCsmck1, ΔCsmkk1, and ΔCsmps1 failed to develop anthracnose disease on pepper fruits due to defects in appressorium formation and invasive hyphae growth. These results suggest that CsMCK1, CsMKK1, and CsMPS1 play important roles in mycelial growth, conidiation, appressorium formation, plant infection, and stress adaption of C. scovillei. These findings will contribute to a better understanding of the roles of the CWI signaling pathway in the development of pepper fruit anthracnose disease.

• KIEAE Journal
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• v.4 no.3
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• pp.121-128
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• 2004

One of the most weak parts for energy loss through the whole building components are building envelopes. Lots of technbologies to increase the thermal performance of building envelopes have been introduced in recent years. Transparent insulation is a new technology for building insulation and has function both solar transmittance and thermal insulation. This study has been carried out to develope the transparent insulation panels and TI-wall system and to analyze the thermal performance of TI-wall system by experiments using test-cell and dynamic energy simulation program ESP-r 9.0. This system is regarded as a efficient building envelope system suitable for to reduce the heating and cooling load of the buildings in our country.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.405-410
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• 2016

Auxins are essential in plant growth and development. The auxin-stimulated elongation of plant cells has been explained by the "acid-growth theory", which was proposed forty years ago. According to this theory, the auxin activates plasma membrane $H^+-ATPase$ to induce proton extrusion into the apoplast, promoting cell expansion through the activation of cell wall-loosening proteins such as expansins. Even though accepted as the classical theory of auxin-induced cell growth for decades, the major signaling components comprising this model were unknown, until publication of recent reports. The major gap in the acid growth theory is the signaling mechanism by which auxin activates the plasma membrane $H^+-ATPase$. Recent genetic, molecular, and biochemical approaches reveal that several auxin-related molecules, such as TIR1/AFB AUX/IAA coreceptors and SMALL AUXIN UP RNA (SAUR), serve as important components of the acid-growth model, phosphorylating and subsequently activating the plasma membrane $H^+-ATPase$. These researches reestablish the four-decade-old theory by providing us the detailed signaling mechanism of auxininduced cell growth. In this review, we discuss the recent research progress in auxin-induced cell elongation, and a set of possible future works based on the reestablished acid-growth model.