• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.3998-4002
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• 2012

With continuing progress of nanotechnologies and various applications of nanoparticles, one needs to develop a quick and fairly standard assessment tool to evaluate cytotoxicity of nanoparticles. However, much cytotoxicity studies on the interpretation of the interaction between nanoparticles and cells are non-mechanistic and time-consuming. Here, we propose a simple screening method for the analysis of the interaction between several AgNPs (5.3 to 64 nm) and fluorescence-dye containing vesicles ($12{\mu}m$) acting as a biomimetic cell-membrane. Fluorescence-dye containing vesicle was prepared using a fluorescence probe (1,6-diphenyl-1,3,5-hexatryene), which was intercalated into the lipid bilayer due to their hydrophobicity. Zeta potential of all materials except for bare-AgNPs (+32.8 mV) was negative (-26 to -54 mV). The morphological change (i.e., rupture and fusion of vesicle, and release of dye) after mixing of the vesicle and AgNPs was observed by fluorescence microscopy, and fluorescence image were different with coating materials and surface charge of x-AgNPs. In the results, we found that the surface charge of nanoparticles is the key factor for vesicle rupture and fusion. This proposed method might be useful for analyzing the cytotoxicity of nanoparticles with cell-membranes instead of in vitro or in vivo cytotoxicity tests.

• 한국동물학회지
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• 제36권2호
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• pp.277-284
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• 1993

A possible involvement of maturation promoting factor (nfPF) in the two-cell block phenomenon was studied by fusion experiments. Germinal vesicle (GlF) ooeyte was fused with a blastomore from late or blocked 2-cell mouse embryos. and germinal vesicle breakdoum (GVBD) of fused GV oocvtes in the presence of dbcAMP (100$\mu$g/ml) was scored as an index of MPF aniviD. GnD was induced approximately 30% by fusion of a blastomere derived from late 2-cell embryos, but not from blocked 2-cell embryos. The rate of GVBD was changed when GV oocyte was fused with a blastomere from late 2-cell embryos which were treated with u-amanitin, puromvcin or colcemid before and after hsion: Treatment of late 2-cell embryos with puromycin (50 Is/mll but not with u-amanitin (100 Is/ml) clearly inhibited GVBD, indicating that do novo protein synthesis maw be required for the appearance of MPF activity in late 2-cell embryos. Treatment of late 2-cell embryos w기h colcemid (0.1 Is/mll doubled GVBD, presumably due to the maintenance of metaphase or mitotic phase. SDS-PAGE and twoiimensional electrophoresis revealed that there was no difference in protein synthetic pattern in late and blocked 2-cell embryos, but three phosphoproteins with 27, 35 and 46 M)a, presumsblv M-phase components were phosphorylated in late 2-cell embryos but not in blocked 2-cell embryos. It seems then that MPF activity is closely related to phosphorylstion of M-phase components in late 2-cell embryos.

• Molecules and Cells
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• 제26권6호
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• pp.517-529
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• 2008

Porosomes are supramolecular, lipoprotein structures at the cell plasma membrane, where membrane-bound secretory vesicles transiently dock and fuse to release inravesicular contents to the outside during cell secretion. The mouth of the porosome opening to the outside, range in size from 150 nm in diameter in acinar cells of the exocrine pancreas, to 12 nm in neurons, which dilates during cell secretion, returning to its resting size following completion of the process. In the past decade, the composition of the porosome, its structure and dynamics at nm resolution and in real time, and its functional reconstitution into artificial lipid membrane, have all been elucidated. In this mini review, the discovery of the porosome, its structure, function, isolation, chemistry, and reconstitution into lipid membrane, the molecular mechanism of secretory vesicle swelling and fusion at the base of porosomes, and how this new information provides a paradigm shift in our understanding of cell secretion, is discussed.

• 대한수의학회지
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• 제22권2호
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• pp.187-195
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• 1982

This paper dealt with the light microscopical and electron microscopical findings on the morphological changes of the liver of Korean native goat injected with toxin (culture filtrate) of Clostridium perfringens which was isolated from Korean native cattle died of acute Clostridium perfringens enterotoxemia. The results observed are summarized as follows. In the microscopical findings, hyperemia and minute hemorrhage of the liver parenchyma, dilatation of hepatic central vein and centrilobular necrosis of liver, cloudy swelling and hydropic degeneration of hepatic cells, and appearance of light eosinophilic granular bodies in the vacuoles were recognized. In the electron microscopical findings, appearance of pinocytotic vesicle (coated vesicle), fusion of these vesicles, formation of vacuole and accumulation of minute granular proteinous materials in the vacuole were observed in the hepatic cells. Decreased number of glycogen granules, swelling and destruction of mitochondria, proliferation of smooth-surfaced endoplasmic reticulum, enlargement of rough-surfaced endoplasmic reticulum, dispersal of thready agranular membranous structure and appearance of secondary lysosome were recognized in the hepatic cell cytoplasm.

• Applied Biological Chemistry
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• 제42권1호
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• pp.12-19
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• 1999

Biopolymer를 생산하는 Bacillus subtilis K-1과 유당 이용능이 있는 Bacillus coagulans를 융합시켜 획득된 융합주에 의해 생산된 biopolymer의 특성 변화, 생산성 향상의 연구의 일환으로 두균주의 융합을 시도하였고 융합주의 특성을 조사하였다. 원형질체 융합은 33% PEG(Mw. 6,000), 1% PVP, 10 mM $CaCl_2$이 함유된 fusion fluid(FF)에서 5분간 반응하였고, 항생제가 함유된 선별배지에 중층 후, 3일간 배양했을 때 Bacillus subtillus coagulans 변이주 들간의 융합빈도는 $4.6{\times}10^{-5}{\sim}1.8{\times}10^{-7}$이었다. 융합주의 세포특성 검토에서 분리된 모든 융합주의 segregation 비는 $1{\sim}6%$로 나타나 유전적으로 안정하였고, 각 균주가 요구하는 영양 요구성 marker와 항생제의 함유배지에서 생육이 확인되었다. 주요 융합주의 DNA함량은 모균주보다 $1.6{\sim}2.7$배 높게 나타났다. 융합주의 전자현미경 관찰에서두 모균주는 간상체로서 두꺼운 세포벽과 이중막을 확인할 수 있었고 원형질체 형성과정에서 팽융된 세포에서 구형의 원형질체 방출이 이루어지고, 원형질체 융합과정 및 형성된 융합체에서 융합체내 전형적인 vesicle이 확인되었으며 모균주보다는 큰 형태의 세포를 확인할 수 있었다.

• 한국발생생물학회지:발생과생식
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• 제15권3호
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• pp.239-247
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• 2011

Spermatogenesis and taxonomic values of mature sperm morphology of in male Septifer (Mytilisepta) virgatus were investigated by transmission electron microscope observations. The morphologies of the sperm nucleus and the acrosome of this species are the cylinder shape and cone shape, respectively. Spermatozoa are approximately 45-50 ${\mu}m$ in length including a sperm nucleus (about 1.26 ${\mu}m$ long), an acrosome (about 0.99 ${\mu}m$ long), and tail flagellum (about 45-47 ${\mu}m$). Several electron-dense proacrosomal vesicles become later the definitive acrosomal vesicle by the fusion of several Golgi-derived vesicles. The acrosome of this species has two regions of differing electron density: there is a thin, outer electron-dense opaque region (part) at the anterior end, behind which is a thicker, more electron-lucent region (part). In genus Septifer in Mytilidae, an axial rod does not find and also a mid-central line hole does not appear in the sperm nucleus. However, in genus Mytilus in Mytilidae, in subclass Pteriomorphia, an axial rod and a mid-central line hole appeared in the sperm nucleus. These morphological differences of the acrosome and sperm nucleus between the genuses Septifer and Mytilus can be used for phylogenetic and taxonomic analyses as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as seen in subclass Pteriomorphia.

• Molecules and Cells
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• 제38권10호
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• pp.866-875
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• 2015

COPI vesicles are essential to the retrograde transport of proteins in the early secretory pathway. The COPI coatomer complex consists of seven subunits, termed ${\alpha}-$, ${\beta}-$, ${\beta}^{\prime}-$, ${\gamma}-$, ${\delta}-$, ${\varepsilon}-$, and ${\zeta}$-COP, in yeast and mammals. Plant genomes have homologs of these subunits, but the essentiality of their cellular functions has hampered the functional characterization of the subunit genes in plants. Here we have employed virus-induced gene silencing (VIGS) and dexamethasone (DEX)-inducible RNAi of the COPI subunit genes to study the in vivo functions of the COPI coatomer complex in plants. The ${\beta}^{\prime}-$, ${\gamma}-$, and ${\delta}$-COP subunits localized to the Golgi as GFP-fusion proteins and interacted with each other in the Golgi. Silencing of ${\beta}^{\prime}-$, ${\gamma}-$, and ${\delta}$-COP by VIGS resulted in growth arrest and acute plant death in Nicotiana benthamiana, with the affected leaf cells exhibiting morphological markers of programmed cell death. Depletion of the COPI subunits resulted in disruption of the Golgi structure and accumulation of autolysosome-like structures in earlier stages of gene silencing. In tobacco BY-2 cells, DEX-inducible RNAi of ${\beta}^{\prime}$-COP caused aberrant cell plate formation during cytokinesis. Collectively, these results suggest that COPI vesicles are essential to plant growth and survival by maintaining the Golgi apparatus and modulating cell plate formation.

• 대한의생명과학회지
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• 제6권1호
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• pp.11-17
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• 2000

SNAP-25는 presynaptic plasma membrane에 위치하는 단백질로서 synaptic vesicle의 docking과 fusion에 있어서 매우 중요한 역할을 한다. 생쥐 SNAP-25$^{2)}$ 유전자와 99%의 높은 homology를 갖고 있는 Z2 cDNA를 probe로 사용하여 쥐의 뇌 cDNA library에서 SNAP-25유전자를 screening하였다. 그 결과 6개 의 양성 클론을 분리 해 냈으며, 이들 각각을 S1, S2, S3, S4, S5, S6으로 명명하였다. 이 중에서 생쥐 SNAP-25와 가장 높은 homology를 보여 주고 있는 S5 클론을 선택하여 염기서열을 분석하였다. 2,100 bp의 염기서열로 구성된 쥐 SNAP-25 cDNA는 206개의 아미노산을 coding하는 618 bp의 open reading frame을 가지고 있으며, ORF는 209~211 bp에 위치하는 AUG codon에서 시작하여 827~829 bp에 위치하는 stop codon TAA에서 끝난다. 3' untranslated region에서 는 28과 19개 의 CA 반복 염기서열을 보여주고 있었으며, SNAP-25 peptide sequence에서 4개의 cystein residues는 84~91에 위치하고 있었으며, amino terminus 부분에서 amphipathic $\alpha$-helix를 형성하고 있는 것을 볼 수 있었다. 사람과 쥐의 SNAP-25 유전자는 88%, 생쥐와 쥐의 경우는 97%의 homology를 보여 주고 있었다. 그리고 사람과 쥐의 ORF에서 염기서열은 94%,생쥐와 쥐의 ORF에서 염기서열은 100%의 homology를 보여주고 있었으며 사람, 생쥐, 그리고 쥐의 ORF에서 아미노산 서열은 100%의 homology를 보여주고 있었다.

• BMB Reports
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• 제40권3호
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• pp.302-314
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• 2007

N type calcium channels (CaV2.2) play a key role in the gating of transmitter release at presynaptic nerve terminals. These channels are generally regarded as parts of a multimolecular complex that can modulate their open probability and ensure their location near the vesicle docking and fusion sites. However, the proteins that comprise this component remain poorly characterized. We have carried out the first open screen of presynaptic CaV2.2 complex members by an antibody-mediated capture of the channel from purified rat brain synaptosome lysate followed by mass spectroscopy. 589 unique peptides resulted in a high confidence match of 104 total proteins and 40 synaptosome proteome proteins. This screen identified several known CaV2.2 interacting proteins including syntaxin 1, VAMP, protein phosphatase 2A, $G_{o\alpha}$, G$\beta$ and spectrin and also a number of novel proteins, including clathrin, adaptin, dynamin, dynein, NSF and actin. The unexpected proteins were classified within a number of functional classes that include exocytosis, endocytosis, cytoplasmic matrix, modulators, chaperones, and cell-signaling molecules and this list was contrasted to previous reports that catalogue the synaptosome proteome. The failure to detect any postsynaptic density proteins suggests that the channel itself does not exhibit stable trans-synaptic attachments. Our results suggest that the channel is anchored to a cytoplasmic matrix related to the previously described particle web.

• 한국어병학회지
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• 제23권3호
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• pp.399-407
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• 2010

10 개체의 붕어, Carassius auratus 아가미뚜껑의 한쪽면에 1-4개체의 거머리, Limnotrachelobdella sinensis들이 기생하고 있었다. 거머리들의 평균 길이는 약 41.0 mm 정도였고, 폭은 11 mm였다. 이들의몸체는 anterior sucker, neck, trunk, posterior sucker로 구성되어 있었고 각각의 평균 길이는 2.3 mm, 7.2 mm, 23.3 mm, 8.7 mm였다. 몸통의 양 옆에는 11쌍의 lateral vesicle이 존재하였다. Anterior sucker를 SEM으로 관찰한 결과 이들은 반구모양으로 중앙에는 proboscis가 나오는 입이 존재하고 있었다. Proboscis는 식도와 바로 연결되어 있었다. 거머리에 의해서 흡혈되어진 붕어의 아가미를 광학현미경으로 관찰하였을 때 새판융합, 새엽 및 새판 상피세포 과증식, 점액세포 증가 및 울혈이 관찰되었다. 하지만 몇몇 개체들에서 나타나는 새엽 상피세포의 괴사 및 수종변성과 식세포의 침투 등은 거머리의 흡혈 활동 이후 세균 혹은 바이러스에 의한 2차 감염이 원인인 것으로 생각되어진다.