• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.131-136
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• 2004

This study was carried out to investigate effect of lipid metabolism in Viscum album lectin on rats. The lectin was purified by sepharose 4B affinity chromatography and gel filtration using sephadex G-150 with plant material from Viscum album collected in Mt. Duk Yui. After 72 h of $CCl_4$ injection (in olive oil, 1:1, 2 mg/kg) there was a significant increase in serum total cholesterol and triglycerige levels relative to the control group. However, treatment of both Viscum album and purified lectin were significantly decreased lipid parameters against the $CCl_4$-induced. Histological observation basically supported the result obtained from serum lipid assay. The livers of rats challenged with $CCl_4$ produced a marked increase of cytoplasmic vacuoles in number, while the number of necrotic cells and swollen hepatocytes did not change significnatly. Rats administered olive oil alone did not alter the normal hepatic architecture. Histological observation of the liver section in rats treated 72 h with either Viscum album purified lectin or $CCl_4$-induced liver lipogenesis showed decreased numbers of cytoplasmic vaculoes and necrotic cells. The normal hepatic architectural pattern was observed in Hematoxylin-eosin stain. These results suggest that Viscum album lectin has a possible protective effect of lipid metabolim in rats.

• Applied Microscopy
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• v.1 no.1
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• pp.11-17
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• 1969

Conidio spores of Aspergillus niger (strain No. NRRL 330) cultured on potato dextrose agar media were studied by electron microscopy, using the thin sectioning techniques. Conidio spores to be sectioned were fixed by triple methods with $K_2Cr_2O_7$, Glutaraldehyde and $OsO_4$. After dehydrated with alcohol, the specimens were embedded in metacrylate and epon resin media, and thinly sectioned by Porter-Blum MT-2. After sectioned these specimens were negative-stained with uranyl acetate and observed. by Hitachi HS-6 electron microscope. The results of this experiment were summarized as follows. 1. The structures of spore ,wall system seem to be formed 4 layers; exosporium, basal layer, spore coat and unit cell membrane. The protuberance of spore surface that was looked like hair appears to be protrusived from the basal layer. 2. The 3 layers of unit cell membrane was constituted outer layer membrane, inner layer membrane and inter-mediate light layer. 3. The structures of intra cytoplasmic membrane appear as spiral form which was consisted of 3 layers membrane system; outer membrane, inner membrane, and intermediate layer, which has pits. 4. The cement substance of spore coat and cortex may be changed quantitatively by physiological state in cell. 5. In some cases, we observed that the ribosome was transformed into poly ribosome group, and the storage materials and the protein crystals were changed variously. It. has been suggested that the morphological change of some cytoplasmic materials may be caused by some specialized function of the physiological stage.

• Molecules and Cells
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• v.22 no.2
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• pp.203-209
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• 2006

TBP (TATA-binding protein)-related factor 2 (TRF2) regulates transcription during a nuber of cellular processes. We previously demonstrated that it is localized in the cytoplasm and is translocated to the nucleus by DNA-damaging agents. However, the cytoplasmic localization of TRF2 is controversial. In this study, we reconfirmed its cytoplasmic localization in various ways and examined its nuclear migration. Stresses such as heat shock, redox agents, heavy metals, and osmotic shock did not affect localization whereas genotoxins such as methyl methanesulfonate (MMS), cisplatin, etoposide, and hydroxyurea caused it to migrate to the nucleus. Adriamycin, mitomycin C and ${\gamma}$-rays had no obvious effect. We determined optimal conditions for the nuclear migration. The proportions of cells with nuclei enriched for TRF2 were 25-60% and 5-10% for stressed cells and control cells, respectively. Nuclear translocation was observed after 1 h, 4 h and 12 h for cisplatin, etoposide and MMS and hydroxyurea, respectively. The association of TRF2 with the chromatin and promoter region of the proliferating cell nuclear antigen (PCNA) gene, a putative target of TRF2, was increased by MMS treatment. Thus TRF2 may be involved in genotoxin-induced transcriptional regulation.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.101-111
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• 1991

Amoeba sp. was cultured under the light and the dark conditions, and the activity of phosphatases was investigated. There was a linear correlation between the early reaction time and the activity of phosphatases when phosphatases were incubated at 30℃. Then the activity of acid phosphatase was about 2 times higher than that of alkaline phosphatase. The activity of phosphatase was optimal at pH 5.0 in acidic part and at pH 8.0 in alkaline part, respectively. The optimal temperature of phosphatases was near the 40℃. The isozyme patterns of cytoplasmic acid phosphatase were compared with those of membraneous one. Both the isozyme patterns were shown to bo polymorphic on the polyacyamide gel, but different band patterns were observed in the isozymes of the cytoplasmic and the membraneous acid phosphatases. The number of Amoeba sp. under the light stimulus for 48 hours decreased negative exponentially from the illumination. The activity of acid and alkaline phosphatases under the illumination of light incresed 1.7 and 1.5 times higher, respectively, than the activity of those under the dark condition. This result apperars to be related to the mechanism of the autophosphorylation.

• Mycobiology
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• v.39 no.2
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• pp.79-84
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• 2011

Nuclear distribution within the extra-radical fungal structures and during spore production in the arbuscular mycorrhizae fungus Glomus intraradices was examined using an in vitro monoxenic culture system. A di-compartmental monoxenic culture system was modified using a nitrocellulose membrane and a coverglass slip for detailed observations. Nuclear distribution was observed using the fluorescent DNA binding probes SYBR Green I and DAPI. Both septate and non-septate mycelial regions were observed, but cytoplasmic contents were only found within non-septate mycelia. Nuclear fluorescent staining revealed that the non-septate hyphal region contained nuclei only with cytoplasm, and that nuclear distribution was limited by septa. Swollen hyphal bodies were often associated with septate and empty-looking hyphae. Cytoplasmic contents filled the swollen hyphal body from the non-septate hyphal region following removal of the septa. As a consequence, the swollen body developed into a new spore. These observations provide understanding about the distribution of AM fungal nuclei within extra-radical mycelia and during spore formation. The results suggest a mechanism by which the development of a cytoplasm-containing mycelium is controlled by the formation or removal of septa to efficiently maintain and proliferate essential contents. This mechanism may provide a survival strategy to the fungus.

• Journal of Life Science
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• v.19 no.8
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• pp.1016-1022
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• 2009

Tapetum is the tissue in which nutrients are supplied to the developing microspore in angiosperm anther. At tetrad stage of microspore, the tapetal cells show maximum development, but they began to be degenerated by apoptotic programmed cell death (PCD) after sporopollenin accumulation in the pollen wall. The initial step of PCD was observed as vacuolar fusion. After that, cytoplasmic condensation and nuclear fragmentation followed. Lipid droplets are degenerated at a relatively late stage of PCD, and orbicular bodies are the last remains in tapetal cells. The cell wall was relatively resistant against vacuolar enzymes in tapetal cells; it was considered the last structure remaining during programmed cell death of tapetum in ginseng anther.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.5
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• pp.183-188
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• 2007

Using BHK cells with stable expression of cardiac $Na^+/Ca^{2+}$ exchanger(BHK-NCX1), reverse mode(i.e. $Ca^{2+}$ influx mode) of NCX1 current was recorded by whole-cell patch clamp. Repeated stimulation of reverse NCX1 produced a cytosolic $Ca^{2+}$-dependent long-term inactivation of the exchanger activity. The degrees of inactivation correlated with NCX1 densities of the cells and were attenuated by reduced $Ca^{2+}$ influx via the reverse exchanger. The inactivation of NCX1 was attenuated by(i) inhibition of $Ca^{2+}$ influx with reduced extracellular $Ca^{2+}$, (ii) treatment with NCX1 blocker($Na^{2+}$), and (iii) increase of cytoplasmic $Ca^{2+}$ buffer(EGTA). In BHK-NCX1 cells transiently expressing TRPV1 channels, $Ca^{2+}$ influx elicited by capsaicin produced a marked inactivation of NCX1. We suggest that cytoplasmic $Ca^{2+}$ has a dual effect on NCX1 activities, and that allosteric $Ca^{2+}$ activation of NCX1 can be opposed by the $Ca^{2+}$-dependent long-term inactivation in intact cells.

• BMB Reports
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• v.50 no.7
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• pp.373-378
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• 2017

The Jun activation-domain binding protein 1 (Jab1) induces p53 nuclear export and cytoplasmic degradation, but the underlying mechanism is poorly understood. Here, we show that phosphorylation at the threonine 155 residue is essential for Jab1-mediated p53 nuclear export. Jab1 stimulated phosphorylation of p53 at T155 was inhibited by curcumin, an inhibitor of COP9 signalosome (CSN)-associated kinases. The T155E mutant, which mimics phosphorylated p53, exhibited spontaneous cytoplasmic localization in the absence of Jab1. This process was prevented by leptinomycin B (LMB), but not by curcumin. The substitution of threonine 155 for valine (T155V) abrogated Jab1-mediated p53 nuclear export, indicating that phosphorylation at this site is essential for Jab1-mediated regulation of p53. Although T155E can be localized in the cytoplasm in the absence of Mdm2, the translocation of T155E was significantly enhanced by ectopic Hdm2 expression. Our data suggests that Jab1-mediated phosphorylation of p53 at Thr155 residue mediates nuclear export of p53.

• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.81-86
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• 2009

The spermiogenesis and mature spermatozoa of Pseudobagrus fulvidraco were described by means of scanning and transmission electron microscopy. Spermiogenesis is characterized by lateral development of the flagellum, nuclear rotation, deep nuclear fossa formation and compaction into thick granules. The spermatozoa exhibit a round head containing a nucleus that lacks an acrosome, and having a midpiece and a flagellum. The midpiece is small and has a short cytoplasm including several mitochondria separated from the tail by the cytoplasmic canal. The flagellum contains the 9+2 classical axoneme structure and has two axonemal fins. The presence of axonemal fins in the flagellum is a common character in Bagridae. The interrelationships among the Bagridae as well as other teleosts are herein discussed.

• Applied Microscopy
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• v.5 no.1
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• pp.1-8
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• 1975

These studies were carried out the observation of polymorphonuclear leukocyte phagocytosis of Candida albicans in vitro and also detected to the cytoplasmic changes of polymorphonuclear leukocyte during phagocytosis by the method of electron microscopy. The results were summarized as follows: 1. In normal polymorphonuclear leukocyte, nuclear lobes showed a preponderance of dense, granular chromatin located peripherally. The cytoplasm of polymorphonuclear leukocyte was not extensive; the cytoplasmic matrix was moderate dense and of a granular appearance. Golgi complex and rough endoplasmic reticulum system was poorly developed. But a various type of granules were seen abundantly. 2. After 30 minutes of incubation, Candida albicans was completely engulfed. These had come to lie in the vacuole which was limited by the membrane. 3. After 90 minutes of incubation, the phagocytic vacuoles were larger, and many granules devoid of membranes were seen within them. Though the granules has lost their membrane after entering the vacuoles. 4. After 2 hours of incubation, the cytoplamsic components of polymorphonuclear leuko cytes were changed their original morphology.