• Journal of Korean Neurosurgical Society
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• 제41권5호
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• pp.306-313
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• 2007

Objective : In permanent distal middle cerebral artery occlusion [pdMCAO] model of rats, the temporal order of subcellular translocation is not fully understood yet. We studied translocation sequence of cytochrome c and apoptosis inducing factor [AIF] after pdMCAO and patterns of expression. Methods : Twenty-one male rats - with ten minutes, 1, 4, 8, 24 and 48 hours of pdMCAO groups - were enrolled. At core and penumbra area of each cerebral cortex, Western blotting of cytochrome c and AIF were performed using cytosolic fractions and then compared with sham specimens. With 48 hours group, the expression of cytochrome c and AIF was examined with immunofluorescent staining. Results : Compared to sham, the cytosolic translocation of cytochrome c significantly increased at all time points [p<0.05]. As early as 10 min after onset of ischemia, it was increased significantly [p<0.01]. The cytosolic translocation of AIF showed gradual increase with the passage of time and significantly increased 8 hours after [p<0.05]. As late as 24 hours and 48 hours after onset of ischemia, there were increased most significantly [p<0.01]. At penumbra, both proteins failed to show significant increase at all time points. At 48 hours after ischemia, colocalization of cytochrome c and AIF were confirmed. Conclusion : Cytosolic translocation of cytochrome c peaks much earlier than that of AIF in pdMCAO model of rat. Caspase dependent apoptosis activates soon after ischemia and later, it can be reinforced by gradually increasing AIF in ischemic core.

• 한국수정란이식학회지
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• 제26권3호
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• pp.171-180
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• 2011

In this study I report that in vitro development rates of bovine nuclear transfer embryos activated either with boar sperm cytosolic factor (SCF) or with ionomycin followed by cycloheximide (CHX) and subsequent in vivo developmental rates after embryo transfer are related to blastocyst quality as evaluated by apoptosis analysis. SCF was extracted from porcine semen then purified for post-activation injection after nuclear transfer. The optimal timing for SCF injection was determined to be at least 22 h post-IVM for parthenogenetic activation of bovine oocyies. A total of 364 oocytes were successfully enucleated and 268 (73.6%) fused and were injected with SCF. The survival rate of fused and injected embryos was 109/113 (96.5%) after 2 h. The cleavage rates of nuclear transfer embryos after 3 d of culture in the ionomycin/CHX treated group were significantly higher than those of the SCF-activated group (93.3% vs 81.7%, p<0.01, respectively). However, at 7 d and 9 d there was no significant difference between the total developmental rates to blastocyst for either treatment group. Total blastocyst cell numbers were also not significantly different between the two activation treatments (ionomycin/CHX: 149.5${\pm}$7.7 vs. SCF: 139.3${\pm}$4.4 cells). In contrast, the apoptotic levels in the SCF blastocysts were higher than those produced after the chemical treatment (28.2${\pm}$5.1% vs. 8.8${\pm}$0.6%, respectively). A total of 18 expanded or hatching blastocysts was transferred to nine synchronized recipients in each activation group; 5/9 (55.5%) and 2/9 (22.2%) were pregnant at 40 d in the ionomycin/CHX treatment and SCF activated group, respectively. However, only one went to term in the ionomycin/CHX treatment while none of the pregnancies from the SCF group were maintained by 90 d. In conclusion, these results suggest that SCF derived from different species is a limited activator to be used for activation after bovine nuclear transfer in lieu of a chemical activation protocol.

• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.333-339
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• 2003

It has been demonstrated that an unidentified cytosolic factor(s) reduces $K_{ACh}$ channel function. Therefore, this study attempted to elucidate the cytosolic factor. Fresh cytosol isolated from normal heart (FC) depressed the $K_{ACh}$ channel activity, but cytosol isolated from the ischemic hearts (IC) did not modulate the channel function. Electrophorectic analysis revealed that a protein of ${\sim}80 kDa was markedly reduced or even lost in IC. By using peptide sequencing analysis and Western blot, this 80 kDa protein was identified as transferrin (receptor-mediated $Fe^{3+}$ transporter, 76 kDa). Direct application of transferrin (100 nM) to the cytoplasmic side of inside-out patches decreased the open probability ($P_o$, 12.7${\pm}6.4%, n=4) without change in mean open time (${\tau}_o$, $98.5{\pm}1.3$%, n=4). However, the equimolar apotransferrin, which is free of $Fe^{3+}$, had no effect on the channel activity (N*$P_o$, $129.1{\pm}13.5$%, n=3). Directly applied $Fe^{3+}$ (100 nM) showed results similar to those of transferrin (N*$P_o$: $21.1{\pm}3.9$%, n=5). However $Fe^{2+}$ failed to reduce the channel function (N*$P_o$, $106.3{\pm}26.8$%, n=5). Interestingly, trivalent cation La3+ inhibited N*$P_o$ of the channel ($6.1{\pm}3.0$%, n=3). Taken together, these results suggest that $Fe^{3+}$ bound to transferrin can modulate the $K_{ACh}$ channel function by its electrical property as a polyvalent cation.

• BMB Reports
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• 제33권6호
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• pp.525-530
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• 2000

The nerve growth factor (NGF) induces neuronal differentiation and neurite outgrowth of PC12 cells, whereas epidermal growth factors (EGF) stimulate growth and proliferation of the cells. In spite of this difference, NGF-or EGF-treated PC12 cells share various properties in cellular-signaling pathways. These include the activation of the phosphoinositide (PI)-3 kinase, 70 kDa S6 kinase, and in the mitogen-activated protein (MAP) kinase pathway, following the binding of these growth factors to intrinsic receptor tyrosine kinases (RTKs). Therefore, many studies have been attempted to access the critical signaling events in determining the differentiation and proliferation of PC12 cells. In this study, we investigated the cytosolic phospholipase $A_2$ ($cPLA_2$) in neurite behavior in order to identify the differences of signaling pathways between the NGF-induced differentiation and the EGF-induced proliferation of PC12 cells. We have showed here that the $cPLA_2$ was translocated from cytosol to membrane only in NGF-treated cells. We also demonstrated that this translocation is associated with NGF-induced activation of phospholipase $C-{\gamma}(PLC-{\gamma})$, which elevates intracellular $Ca^{2+}$ concentration. These results reveal that the translocation of $cPLA_2$ may be a requisite event in the neuronal differentiation of PC12 cells. Various phospholipase inhibitors were used to confirm the importance of these enzymes in the differentiation of PC12 cells. Neomycin B, a PLC inhibitor, dramatically inhibited the neurite outgrowth, and two distinct $PLA_2$ inhibitors, 4-bromophenacyl bromide (BPB) and arachidonyltrifluoro-methyl ketone ($AACOCF_3$) also suppressed the neurite outgrowth of the cells, as well Taken together, these data indicated that $cPLA_2$ is involved in NGF-induced neuronal differentiation and neurite outgrowth of PC12 cells.

• BMB Reports
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• 제29권6호
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• pp.507-512
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• 1996

The NADPH oxidase of phagocytes catalyzes the reduction of oxygen to $O_{2}^{-}$ at the expense of NADPH The enzyme is dormant in resting neutrophils and hecomes activated on stimulation. During activation. $p47^{phox}$ (phagocyte oxidase factor), a cytosolic oxidase subunit, becomes extensively phosphorylated on a number of serines located between S303-S379. Although the biochemical role of phosphorylation is speculative, it has been suggested that phosphorylation could neutralize the strongly cationic C-terminal which may result in the change of conformation of $p47^{phox}$ and subsequent translocation of this protein and other cytosolic components to the membrane. In order to mimic the effect of phosphorylation in terms of neutralizing the positive charges, recombinant $p47^{phox}$ was treated with phenylglyoxal, which removes positive charges of arginine residues. Modification of recombinant $p47^{phox}$ resulted in the activation of oxidase in a cell-free translocation system as well as a conformational change in recombinant $p47^{phox}$ which may be responsible for the activation of the enzyme.

• Molecules and Cells
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• 제21권3호
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• pp.381-388
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• 2006

Heat shock proteins (Hsp) 70 are a ubiquitous family of molecular chaperones involved in many cellular processes. A yeast strain, ssa1/2, with two functionally redundant cytosolic Hsp70s (SSA1 and SSA2) deleted shows thermotolerance comparable to mildly heatshocked wild type yeast, as well as increased protein synthesis and ubiquitin-proteasome protein degradation. Since mRNA abundance does not always correlate well with protein expression levels it is essential to study proteins directly. We used a gel-based approach to identify stress-responsive proteins in the ssa1/2 mutant and identified 43 differentially expressed spots. These were trypsin-digested and analyzed by nano electrospray ionization liquid chromatography tandem mass spectrometry (nESI-LC-MS/MS). A total of 22 non-redundant proteins were identified, 11 of which were confirmed by N-terminal sequencing. Nine proteins, most of which were up-regulated (2-fold or more) in the ssa1/2 mutant, proved to be stress-inducible proteins such as molecular chaperones and anti-oxidant proteins, or proteins related to carbohydrate metabolism. Interestingly, a translational factor Hyp2p up-regulated in the mutant was also found to be highly phosphorylated. These results indicate that the cytosolic Hsp70s, Ssa1p and Ssa2p, regulate an abundance of proteins mainly involved in stress responses and protein synthesis.

• 생명과학회지
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• 제19권12호
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• pp.1685-1689
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• 2009

파이토킬레이트(PC)는 PCS에 의해 생성되는 작은 폴리펩타이드로서 여러 생물에서 발견되고 있다. PC의 역할은 카드뮴과 같은 중금속을 세포질에서 결합하며 이는 액포막에 존재하는 HMT에 의해서 액포 안으로 이동된다. HMT1은 분열효모에서 처음으로 알려졌으며 이후 선충, 초파리 등에서도 발견되었으며 세포 내 역할은 카드뮴 같은 중금속 해독에 관여를 하고 있다. 하지만 액포가 존재하지 않고 PC를 생성하지 않는 초파리에서의 HMT1의 발견은 그 동안 알려진 HMT1의 역할을 재 조명하게 된다. 따라서 PC를 생성하지 못하는 출아효모에 PC를 생성하는 분열효모 유래 SpHMT1을 발현시켜 카드뮴에 대한 저항성을 분석하였다. SpHMT1을 발현하는 출아효모는 카드뮴에 대한 저항성이 현저하게 증가되었고 이는 SpHMT1이 PC가 존재하지 않는 조건에서도 카드뮴에 대한 해독작용을 하는 것을 암시한다. 또한 SpHMT1을 발현하는 출아효모는 GSH에 대한 저항성을 보였고 카드뮴에 대한 저항성도 GHS에 의해서 더 증가되는 결과를 보였다. 이러한 결과는 HMT1이 PC와 결합된 카드뮴을 액포안으로 이동시키는 가능성보다 GSH와 결합된 카드뮴을 액포 안으로 이동시켜 카드뮴에 대한 해독작용을 한다는 것을 암시한다.

• Journal of Acupuncture Research
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• 제21권5호
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• pp.179-190
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• 2004

Objectives : The purpose of this study was to investigate the effect of Bee Venom and Melittin acupuncture solution on the lipopolysaccharide and sodium nitroprusside- induced expression of cytosolic phospholipase $A_2$, tumor necrosis factor-${\alpha}$ and calcium concentration in RAW 264.7 cells, a murine macrophage cell line. Methods : The expression of cytosolic phospholipase $A_2$ and tumor necrosis factor-${\alpha}$ was determined by western blotting with corresponding antibodies, and the generation of intracellular calcium concentration was investigated by delta scan system in RAW 264.7 cells. Results : 1. Compared with control, expressions of lipopolysaccharide-induced cytosolic phospholipase $A_2$ were decreased significantly by $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution and decreased by 0.5, $1{\mu}g/mL$ of bee venom. 2. Compared with control, expressions of sodium nitroprusside-induced phospholipase $A_2$ were decreased significantly by 0.5, 1, $5{\mu}g/mL$ of bee venom and by 5, $10{\mu}g/mL$ of melittin acupuncture solution. 3. Compared with control, expressions of lipopolysaccharide-induced tumor necrosis factor-${\alpha}$ were decreased significantly by $10{\mu}g/mL$ of melittin acupuncture solution and were not changed significantly by 0.5, 1, $5{\mu}g/mL$ of bee venom and $5{\mu}g/mL$ of melittin acupuncture solution. 4. Compared with control, expressions of sodium nitroprusside-induced tumor necrosis factor-${\alpha}$ were decreased significantly by 1, $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution and decreased by $0.5{\mu}g/mL$ of bee venom 5. Compared with control, lipopolysaccharide-induced intracellular calcium concentrations were decreased by 0.5, 1, $5{\mu}g/mL$ of bee venom and $10{\mu}g/mL$ of melittin acupuncture solution and increased by $5{\mu}g/mL$ of melittin acupuncture solution. 6. Compared with control, sodium nitroprusside-induced intracellular calcium concentrations were decreased by 0.5, 1, $5{\mu}g/mL$ of bee venom and 5, $10{\mu}g/mL$ of melittin acupuncture solution.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.897-905
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• 2003

Phospholipase D (PLD) and ADP-ribosylation factor (ARF) were partially purified on a series of column chromatography, and their biochemical properties were characterized to understand the regulatory mechanism of PLD activation by ARF protein in the antigen-induced immune responses in guinea pigs. Heparin Sepharose and high-Q Sepharose column chromatographies were used for the purification of PLD, and Sephadex G-25, DEAE Sephacel, Source 15 PHE (HIC), Superdex-75, and Uno-Q column chromatographies were used for the purification of ARF. The purified PLD and ARF proteins were identified with anti-rabbit PLD- or ARF-specific antibodies, showing about 64 or 85 kDa for the molecular mass of PLD and 29 or 35 kDa for the sizes of ARF. Partial cDNA of ARF3 was cloned by RT-PCR in guinea pig lung tissue and its nucleotides and amino acids were sequenced. Guinea pig ARF3 showed 92% of nucleotides sequence identity and 100% of amino acid sequence homology with human ARF3. The ARF-regulated PLD activity was measured in the oleate or ARFs-containing mixed lipid vesicles. The purified and recombinant ARF (rARF) activities were assessed with the $GTP{\gamma}S$ binding assay. The PLD activity was induced by oleate in a dose-dependent manner. The purified ARF and recombinant ARF3 increased PLD activity in guinea pig lung tissues. These data show that the activity of membrane-bound PLD can be regulated by the cytosolic ARF proteins, suggesting that ARF proteins in guinea pig lung can act as a regulatory factor in controlling the PLD activity in allergic reaction.

• 생명과학회지
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• 제21권8호
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• pp.1100-1108
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• 2011

흰쥐에서 내독소로 유도된 급성 폐손상에서 moxifloxacin의 효과를 형태학적으로 호중구의 폐장 내 침윤 및 세포질형 포스포리파아제(cytosolic phospholipase A2) 발현과 관련하여 알아보았다. 내독소는 잘 알려진대로 흰쥐에서 급성 폐손상을 유발하였고 이때 폐장 내의 호중구의 침윤 및 폐장 및 호중구에서의 세포질형 포스포리파아제의 발현이 증가하였고, 또한 염증성 사이토카인의 일종인 종양괴사성인자(tumor necrosis factor)의 발현도 증가하였다. 전자현미경을 이용한 산소기 생성의 검사에서도 내독소에 의하여 산소기의 생성이 폐장 내에 증가한 사실을 확인하였고, 산화성 스트레스에 유발되는 제2형 폐포세포에서의 층상체의 변화도 관찰하였다. 면역변환효과가 있다고 알려진 moxifloxacin은 이러한 변화들을 억제하고 형태학적으로 내독소에 의한 급성 폐손상을 현저히 감소시켰다.