• Korean Journal of Microbiology
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• v.38 no.4
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• pp.218-218
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• 2002

Using two drugs, tunicamycin and brefeldin A, which affect protein processing, we investigated the intracellular processing mechanism of secreted aspartyl proteinase 1 (SAPl) of Candide albicans. Three intracellular forms of SAPI were detected by immunoblotting using menoclonal antibody (MAb) CAPl. Their molecular weights were approximately 40, 41 and 45 kDa, respectively. The 41 kDa protein is a glycoprotein and may be the same as the extracellular form judging by its molecular mass. The 40 kDa protein was the unglycosylated form and its molecular mass coincided with deglycosylated SAPl and the 45 kDa protein was also the unglycosylated form. Neither the 40 and 45 kDa proteins were detected in the culture supernatant of C. albicans. These suggested that the 40 and 45 kDa proteins might be intracellular precursor forms of SAPI. These results show that SAPI is translated as a 45 kDa precusor form in the endoplasmic reticulum and the 45 kDa precursor farm undergoes proteolytic cleavage after translocation into the Golgi apparatus, generating the 40 kDa precursor form. This 40 kDa precursor is converted into a 41 kDa mature form through glycosylation in the Golgi apparatus. The mature form of the 41 kDa protein is sorted into secretary vesicles and finally released into the extracellular space through membrane fusion. When the glycan region of SAPl was digested with N-glycosidase F, both stability and activity of the enzyme decreased. These results indicate that the glycan attached to the enzyme may, at least in parti be related to enzyme stability and activity.

• Applied Microscopy
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• v.27 no.2
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• pp.131-144
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• 1997

The present study was carried out to investigate the processes of the ultrastructural differentiation and the acetylcholinesterase (AChE) activities of the developing rat retina. The results are as follows. The retina of fetal rat on the 13th day of gestation showed the early stage of differentiation. Briefly, there appeared dividing chromosomes, the plentiful free ribosomes, and the high ratio of nucleus to cytoplasm. The reaction products by AChE were localized at the membrane of endoplasmic reticulum and on the outer membrane of nucleus. Ultrastructures and AChE activities in the retina of the fetal rats on the 18th day of gestation were similar to those of the prior stages, except the appearence of rough endoplasmic reticulum and Golgi apparatus. According to the ultrastructural observations, the rat retina was still in immature state at birth, but the pigment epithelial cells were fully differentiated, e. g. the increase of melanin granules, the development of mitochondria and Golgi apparatus. The AChE activity was weekly detected. The differentiated retinal layers and the outer segment of photoreceptor cells were observed on the 7th postnatal day. And the pigment epithelium appeared to be fully differentiated. On the 14th postnatal day, rat retina were completely differentiated. In other words, the rat retina was characterized by the prominent outer segments, phagocytosed residues in the pigment epithelium, and the localization of reaction products by AChE in the synapses. In conclusion, the differentiation of rat retina is charaterized by the changes of cell shape, the increase of retinal layers, and the alterations of AChE activities. It seems that rat retina is to be functional from 2 weeks of birth onward, coinciding with the eye opening of the juvenile rats.

• Applied Microscopy
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• v.13 no.1
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• pp.71-84
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• 1983

This study was made to investigate the ultrastructural changes of the hepatocyte of the maternal liver, and fetal liver by Actinomycin D in Wistar rats at the stage of pregnancy. Peritoneal injection of Actinomycin D to rats carried out gestation day 7 to 9 at the level of $15{\mu}g(11.5{\mu}g/100g$ body wt.), $20{\mu}g(15.8{\mu}g/100g$ body wt.) on each day. Treated animals with saline only were used for controls. Animals were sacrificed on day 15 of gestation. On electron microscopic examination, the hepatocytes of maternal liver given Actinomycin D $15{\mu}g$/ml had evidence of serious cellular damage, for example, hypertrophy of rough endoplasmic reticulum, loss in nucleolar osmiophilia, swelling of Golgi apparatus and change of mitochondrial structure. Maternal liver given Actinomycin D $20{\mu}g/ml$ shown similar changes to that of the $15{\mu}g/ml$ treated animals. But mitochondria of this group were not changed than that of $15{\mu}g/ml$ treated group. In the hepatocytes of fetal liver, changes were more pronounced. The drug produced alteration in nuclei and cytoplasm. The rough endoplasmic reticulum was swollen and there were ribosomes detachement. In addition, damages of mitochondria, Golgi apparatus were detected.

• Applied Microscopy
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• v.25 no.1
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• pp.75-85
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• 1995

The goal of the present study is to investigate the precise variation of tubulin substances in the cytoplasm of oviductal ciliated cells and the morphological changes in cytoplasmic organelles of ciliated cells for ciliogenesis by estrous cycles. The animals used in this study were female rat (Sprague Dawley strain), weighing approximately 200 gm. The ampulla oviducts of these animals (at each of estrous cycle) were rapidly excised. At each stage of estrous cycle, the tissues were used for immunocytochemical study and other were used for electron microscopical study. All specimens were observed by the light and electron microscope. The results obtained are as follows: 1. In the ciliated cells at proestrus, Golgi complex showed $5{\sim}7$ stacked cisternae with numerous saccules and vacuoles. Large amount of fibrous granules were located near the Golgi complex. But at metestrus and diestrus, few fibrous granules were seen. 2. A moderate number of rough endoplasmic reticulum and polyribosomes were scattered in the cytoplasm of ciliated cells at proestrus, but were decrease in number at metestrus and diestrus. 3. At proestrus and estrus, there were a large amount of vesicles in the apical cytoplasm of ciliated cells. 4. Numerous mitochondria were located in the apical cytoplasm at proestrus and estrus, but only a few at metestrus and diestrus. 5. At proestrus and estrus, tubulin substances showed strong reactions in the cytoplasm but weak reactions at metestrus and diestrus. It is suggested consequently that the ciliated cells of the rat oviducts showed no morphological changes of cilia but the ultrastructural organelles of the cells were changed in its shape and location during the entire estrous cycle.

• Applied Microscopy
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• v.22 no.2
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• pp.118-126
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• 1992

The pathway and time course of fucose-containing glycoprotein synthesis and intracellular translocation in osteoclasts of the mice maxillary alveolar bone were investigated by electron microscopic radioautography. Male Balb-C mice weighing 17gm were anesthetized with Nembutal and injected via the external jugular vein with 2.5 mCi of $L-[6-^{3}H]-fucose$ (specific activity 16.8 mCi/mmol) in 0.1 ml of sterile saline solution. At 5, 10, 20, 35 minutes and 8 hours after administration of the $^{3}H-fucose$, animals were killed by intracardiac perfusion of 30ml of 2% glutaraldehyde in a modified Tyroid solution, pH 7.4. The maxillae were then removed and further fixed in Karnovsky fixative for an additional 3-4 hours. After rinsing in 0.1M cacodylate buffer for 10 minutes, the maxillae were demineralized for 2 weeks at $4^{\circ}C$ in ethylene diamine tetra acetate containing 2% glutaraldehyde. The first interdental areas were mesiodistally sectioned into slices of 1mm thickness and postfixed in osmium tetroxide. Tissues were then dehydrated and embedded in Poly Bed. To prepare electron microscopic radioautography, the dipping method of Kopriwa (1973) was employed. Thin sections were coated with a crystalline monolayer of ILford $L_4$ photographic emulsion. After exposure for 4 months at $4^{\circ}C$, the sections were developed Kodak Microdol-X and Phenidon (for compact grains), fixed in 30% sodium thiosulfate, stained with uranyl acetate and lead citrate and examined in the electron microscope (JEOL 1200 EX). At 5, 10 and 20 minutes after injection, $^{3}H-fucose$ was concentrated in Golgi cisternae of the osteoblasts. By 35 minutes the labels were observed over small vesicles in the suprannclear area of osteoclasts. At 8 hours, numerous silver grains were located on the ruffled border and cell membrane of osteoclasts. These results indicate that fucose molecules are added in the Golgi apparatus and small vesicles appear to be responsible for translocation of the glycoproteins to the marginal portion of osteoblasts. The glycoproteins are distributed on the osteoclast cell surface and especially over the ruffled border.

• Applied Microscopy
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• v.2 no.1
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• pp.17-31
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• 1972

Light and electron microscopic studies were made to investigate the morphological changes in growing galls on the leaf of Lycium chinense MILL caused by Eriophyes kuko Kishda. The results are summarized as follows: 1. Light microscopy At the early stage of the invasion of E. kuko on the back side of the young leaf of L. chinense, the.epidermal cells become hypertrophic and develope a gall. As the gall grows, the cells of both palisade and spongy-layers become hypertrophic and these tissues are hard to be distinguished because of their irregular outgrowth. As the gall grows, the nuclei of the gall also become hypertrophic and larger than these of normal cells. 2. Electron microscopy Under electron microscopy the mitochondria, the golgi apparatus and the plastids of the advanced galls are degenerated and disintergrated and the cell walls become thicker than normal ones. The characteristic star bodies and the ring-form structures are found in the mature gall cells.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.330-339
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• 1995

In Helice tridens tridens, hylaine cells, small granulocytes, and large granulocytes were identified. Features of hyaline cells include a large nucleus in proportion to the cytoiplasm, and weak electron-dense granules of oval shape and vesicles, and endoplasmic reticulum (ER) in the cytoplasm. Small granulocytes have smaller nucleus than that of the hyaline cells, well-developed ER, Golgi complex, and small, round and electron-dense granules in the cytoplasm. Large granulocytes contain large and electron dense granules (ahout 1 $\mu$m) that fused small granules. Hemocytes of Helice tridens tridens differentiated from hyaline cell to large granulocyte granules of hyaline cells have lysosome and make small vesicles from nuclear envelopes. While these vesicles pass through the Golgi complex, they are filled with electron dense matetials, and then fused with the small granules. They eventually matured into large granules. All of hemocytes have the glycogen particles. In the large granulocytes heterogeneouse granules were supposed to occur by disappearance of granules.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.425-434
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• 1999

The morphological studies on the cecal development in the 60-, 90-, and 120-day-old fetuses and the newborns of Korean native goats were investigated by scanning and transmission electron microscopy. The results were summarized as follows ; Scanning electron microscopic studies : 1. In the 60-day-old fetuses, fold-like shapes protrusion on the cecal mucosa surface appeared. In the 90-day-old fetuses, the cecal villi appeared to be columnar shapes. In the 120-day-old fetuses, the cecal villi showed various tongue-like or columnar shapes. In the newborns, only the rudimental trace of the villi and the intestinal glands were observed. Transmission electron microscopic studies : 2. In the 60-day-old fetuses, the cecal epithelia were simple columnar in some areas and stratified columnar in others, and the epithelial cells contained nuclei, nucleoli, ER, mitochondria, Golgi complexes, zonula occludens, desmosomes, digitiform intercellular junctions, and large masses of the glycogen granules. 3. In the 90-day-old fetuses, the cecal epithelia were simple columnar in some area and stratified columnar in other. The microvilli of the cecal epithelia became much larger and longer than those in the 60-day-old fetuses, and intercellular junctions were developed, and increased numbers of ER, mitochondria, Golgi complexes were observed and the goblet cells contained a lot of the secretory granules. 4. In the 120-day-old fetuses, the cecal epithelia were only simple columnar in all areas. Microvilli and cytoplasmic organelles were well developed and the irregular annular nuclei were observed. 5. In the newborns, the cecal epithelia were covered with extensive microvilli, and the goblet cells with secretory granules were protruded into the lumen. And some goblet cells secreted the secretory granules into the lumen.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.25-39
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• 1997

The morphology of the ductuli efferentes of the Korean native pheasants were observed in order to obtain a basic data for further studying reproductive physiology and other male genital organs. The mature (14-16 months after hatching) male pheasants were used in this study. The specimens from pheasants were collected on a monthly basis. The general morphological changes of the ductuli efferentes were observed with hematoxylineosin stain, and semithin section by light microscope. The ultrastructural changes of the ductuli efferentes were investigated with ultrathin section by transmission electron microscope. The results obtained are summarized as follows : 1. During the breeding season, the average height of ductuli efferentes epithelium was $23.45{\pm}2.34{\mu}m$ and was largely decreased by $17.85{\pm}2.01{\mu}m$ during the non-breeding season. The thickeness of interstitial tissue was comparatively increased during the non-breeding season. 2. During the breeding season, the epithelial cells of ductuli efferentes were well developed. During the non-breeding season, epithelial layer and lumen of ductuli efferentes, were markedley reduced compared with those of breeding season. 3. Morphological changes of the ductuli efferentes underwent periodic changes paralleling to the spermatogenic cycle. 4. At least two different cell types were identified in the epithelium of ductuli efferentes, namely non-ciliated and ciliated cells. 5. The ciliated cells possess many vesicles, slightly smaller than those of the non-ciliated cells. 6. The ciliated cells contained numerous mitochondria, smooth and rough endoplasmic reticulum, Golgi complex, lysosome, and oval nuclei. The non-ciliated cells had a irregular nuclei and a cytoplasm containing few organelles. 7. During the breeding season, a number of vesicles, rough and smooth endoplasmic reticulum, Golgi complex, and mitochondria were distinctively showed in the epithelial cells but in the non-breeding season only a few observed.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.5
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• pp.1231-1243
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• 2016

The ultrastructural study on oocyt development and the process of vitellogensis in the oocytes during oogenesis in female Pampus echinogaster were investigated by electron microscope observations. In the previtellogenic phase, in particular, several intermitochondrial cements appear in the cytoplasms of the chromatin nucleleolus oocyte and perinuclear oocyte. The number of intermitochondrial cements are associated with the multiplication of the number of mitochondria in the early developmental stage. In the early vitellogenic phase, the Golgi complex in the cytoplasm of the yolk vesicle oocyte is involved in the formation of yolk vesicles containing carbohydrate yolks. At this time, many pinocytotic vesicles containing yolk precursors (exogenous substances) by pinocytosis are observed in the cytoplasm near the region of initial formation of the zona pellucida. In the late vitellogenic phase, two morphological different bodies, which formed by the modified mitochondria, appeared remarkably in the yolked oocytes. The one is the multivesicular bodies and another is yolk precursors. The multivesicular bodies were transformed into the primary yolk globules, while yolk precursors were connected with exogeneous pinocytotic vesicles near the zona pellucida. After the pinocytotic vesicles were taken into yolk precursors, the yolk precursors were transformed into the primary yolk globules. Thereafter, primary yolk globules mixed with each other, eventually, they developed into secondary and tertiary yolk globules. In this study, vitellogenesis of this species occurred by way of endogenous autosynthesis and exogenous heteogenesis. Vitellogenesis occurred through the processes of endogeneous autosynthesis, involving the combined activity of the Golgi complex, mitochondria and multivesicular bodies formed by modified mitochondria. However, the process of heterosynthesis involved pinocytotic incorporation of extraovarian precursors (such as vitellogenin in the liver) into the zona pellucida (by way of granulosa cells and thecal cells) of vitellogenic oocytes.