• 한국식물병리학회지
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• 제10권2호
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• pp.83-91
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• 1994

Stem tissues of tomato plants (cv. Kwanyang) inoculated with Phytophthora capsici were examined by light and electron microscopy to compare early cytological differences between comaptible and incompatible interactions of tomatoes with the fungus. Twenty four hours after inoculation, the compatible isolate S 197 colonized severely the epidermis, cortex, and xylem vessels of stem tissue, whereas only few fungal cells colonized the stem tissues inoculated with the incompatible isolate CBS 178.26. Fragmented plasma membrane, distorted chloroplast, degraded cell wall, remnants of host cytoplasm were early ultrastructural features of the damaged host cell observed both in the compatible and incompatible interaction, a number of vesicles were distributed in the space between fungal cell walls and plasma membrane. The degradation of host cell walls by P. capsici was more pronounced in the compatible than the incompatible interactions. The incompatible interactions of tomato cells with P. capsici were characterized by formation of host cell wall apposition in the cortical parenchyma cells, indicating that the apposition of electron-dense material from the host cell walls may function as a plant defense reaction to the fungus. The fungal cells encased by wall appositions had abnormal cytoplasm and separated plasma membranes. The haustorium which formed from the fungal hyphae did not further penetrate through the host wall apposition and cytoplasmic aggregation, especially in the incompatible reactions. In contrast, the haustorium of the compatible isolate S 197 was not encased by wall appositions.

• Applied Microscopy
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• 제15권2호
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• pp.69-79
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• 1985

Ultrastructural and cytochemical studies of the root hair cell and the trichoblast were undertaken with light and electron microscopes to clarify the type of root hair, fine structure and the activities of acid phosphatase and ATPase. The root hair was differentiated from the middle portion of the cell, and perpendicularly to the long axis of the cell. Consequently, the type of root hair comes under the panicoid type. In the trichoblast, nucleus and cytoplasm are located in the vicinity of cortex. On the contrary, after the root hair is formed, they migrate to the apical region of the root hair, and the basal region of the root hair is filled with numerous vacuoles. Cell walls of actively growing root hairs are subdivided into two layers on the basis of the arrangement of cellulose microfibrils. New cell wall of the root hair is presumptively formed from Golgi complex-derived vesicles. Activity of acid phosphatase appeared on tonoplast, plasma membrane, and nuclear envelope, whereas ATPase activity appeared on the plasma membrane, heterochromatin, and mitochondrial cristae.

• 한국연초학회지
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• 제17권1호
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• pp.33-40
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• 1995

Structures of the adventitious root meristem induced from callus culture of tobaco (Nicotiana tabacum cv. NC 82) leaves were investigated by light and transmission electron microscopy. Structural differences between in vitro root and callus cells were also examined by the microscopy. The submicroscopic features of the in vitro root cells were as follows. Intercellular spaces were not developed and nuclei with two nucleoli were observed occasionally. Plasmodesmate were found in groups or sing1y on transverse and longitudinal walls. Amyloplast solely filled with starch grains, with one to five electron - dense bands, was surrounded by single membrane. in the callus cells, vacuolization of central part in the cytoplasm having mitochondria with swollen cristae and starch grains like those of in vitro root cells was a distinct feature. Vesicles which were found between cell wall and plasma membrane may be arisen by a process of protoplasmic invagination. By comparing of ultrastructures between the cells of callus and in vitro roots we found that the distinct differences lied on thickened cell walls and hypertrophed vacuoles in the former, and less thickened cell walls and several small vacuoles in the later.

• The Korean Journal of Physiology and Pharmacology
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• 제16권6호
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• pp.413-422
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• 2012

The purpose of this study is to investigated the mechanism of pharmacological action of local anesthetic and provide the basic information about the development of new effective local anesthetics. Fluorescent probe techniques were used to evaluate the effect of lidocaine HCl on the physical properties (transbilayer asymmetric lateral and rotational mobility, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex, and liposomes of total lipids (SPMVTL) and phospholipids (SPMVPL) extracted from the SPMV. An experimental procedure was used based on selective quenching of 1,3-di(1-pyrenyl)propane (Py-3-Py) and 1,6-diphenyl-1,3,5-hexatriene (DPH) by trinitrophenyl groups, and radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py. Lidocaine HCl increased the bulk lateral and rotational mobility of neuronal and model membrane lipid bilayes, and had a greater fluidizing effect on the inner monolayer than the outer monolayer. Lidocaine HCl increased annular lipid fluidity in SPMV lipid bilayers. It also caused membrane proteins to cluster. The most important finding of this study is that there is far greater increase in annular lipid fluidity than that in lateral and rotational mobilities by lidocaine HCl. Lidocaine HCl alters the stereo or dynamics of the proteins in the lipid bilayers by combining with lipids, especially with the annular lipids. In conclusion, the present data suggest that lidocaine, in addition to its direct interaction with proteins, concurrently interacts with membrane lipids, fluidizing the membrane, and thus inducing conformational changes of proteins known to be intimately associated with membrane lipid.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.41-46
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• 2002

Effect of cadmium (Cd) intoxication on renal acid-base regulation was studied in adult male Sprague-Dawley rats. Cd intoxication was induced by subcutaneous injections of $CdCl_2$ at a dose of 2 mg Cd/kg/day for $3{\sim}4$ weeks. In Cd-intoxicated animals, arterial pH, $PCO_2$ and plasma bicarbonate concentration decreased, showing a metabolic acidosis. Urine pH and urinary bicarbonate excretion increased and titratable acid excretion decreased with no change in ammonium excretion. In renal cortical brush-border membrane vesicles derived from Cd-exposed animals, the $Na^+/H^+$ antiporter activity was significantly attenuated. These results indicate that chronic exposures to Cd impair the proximal tubular mechanism for $H^+$ secretion (i.e., $Na^+/H^+$ antiport), leading to a metabolic acidosis.

• BMB Reports
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• 제34권2호
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• pp.118-122
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• 2001

The translocation of ribose-binding protein (RBP) into the inverted membrane vesicles (IMV) of Escherichia coli and eukaryotic microsomes was studied using the in vitro translation/translocation system. It was found that RBP was translocated into heterologous eukaryotic microsomes co-translationally, as well as post-translationally However, RBP was translocated only past-translationally into IMV. Degradation fragments of RBP with the molar mass of 14 and 16 kDa were produced during the translocation into IMV However, the amount of the degradation products decreased and the mature form of RBP appeared in the presence of phenylmethylsulfonyl fluoride (PMSF). PMSF and GTP accelerated the translocation of RBF It was also found that SecB enhanced the post-translational translocation of RBP It appears that RBP is translocated via at least two targeting paths.

• 한국동물학회지
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• 제33권4호
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• pp.428-434
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• 1990

꿀벌부채명나방의 난소가 지방체에서 합성한 난황전구물질(vitellogenin)을 흡수,저장하는 과정을 추적하기 위하여$^3$H-leucine을 이용하여 방사능으로 표지된 난황전구물질을 지방체세포에서 합성,분리한후 성숙중인 난소와 함께 배양함으로써 난황전구물질의 이동경로를 조사하였다. 표지된 난황전구물질은 여포세포를 통과하거나 여포세포간극을 통하여 난모세포에 접근하였고 원형질막을 투과하여 난황과립에 도달하였다. 배양시간이 오래 경과된 난모세포일수록 표지 된 난황과립을 많이 포함하였다.

• Macromolecular Research
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• 제17권12호
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• pp.956-962
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• 2009

We investigated the effect of two nonlamellar-prone lipids, phosphatidylethanolamine (PE) and dioleoylglycerol (DOG), on the efficiency of protein encapsulation in liposomes. When the phosphatidylcholine (PC) matrix was replaced with PE or DOG during liposome formulation, the amounts of glutathione S-transferase and bovine serum albumin entrapped in the vesicles increased with increasing PE or DOG concentration. The presence of PE and DOG synergistically affected protein entrapment. These results suggest that protein encapsulation can be enhanced by the presence of nonlamellar lipids and/or lipid-induced membrane properties.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.743-748
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• 2013

The temperature dependence of the partition coefficients of a neuropeptide, substance P (SP), in isotropic acidic bicelles was investigated by using a pulsed field gradient nuclear magnetic resonance diffusion technique. The addition of negatively charged dimyristoylphosphatidylserine to the neutral bicelle changed the SP partitioning a little, which implies that the hydrophobic interaction between the hydrophobic residues of SP and the acyl chains of lipid molecules is the major interaction while the electrostatic interaction is minor in SP binding in a lipid membrane. From the temperature dependence of the partition coefficients, thermodynamic functions were calculated. The partitioning of SP into the acidic bicelles is enthalpy-driven, as it is for small unilamellar vesicles and dodecylphosphocholine micelles, while peptide partitioning into a large unilamellar vesicle is entropy-driven. This may mean that the size of lipid membranes is a more important factor for peptide binding than the surface curvature and surface charge density.

• Archives of Pharmacal Research
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• 제15권4호
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• pp.298-303
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• 1992

Synaptosomal plasma membrane vesicles (SPMV) were isolated from fresh bovine cerebral cortex. The effects of barbiturates on the rotational relaxation time of 1.6-diphenyl-1, 3, 5-hexatriene (DPH) in intact SPMV and model membranes of total lipids (SPMVTL) and phosphlipids (SPMVPL) extracted from SPMV were examined. Barbiturates decreased the rotational relaxation time of DPH in intact SPMV in a dose-dependent manner. In contrast, they did not affect the rotational relaxation time of DPH in SPMVTL and even dose-dependently increased the rotational relaxation time of DPH in SPMVPL.