• 자연과학논문집
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• 제15권1호
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• pp.79-88
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• 2005

효모에는 여러 가지 종류의 thiol peroxid se 동위 효소들인 cytoplasmic TPx I, cTPx II, cTPx III, mitochodrial TPx (mTPx), 및 nuclear TPx (nTPx)가 존재하고 있다. 특히 cTPx II는 다른 효모TPx와 비교해 볼 때 매우 낮은 peroxidase 활성을 보이나, cTPx II를 제거한 cTPx II mutant균주는 심하게 성장이 저해되는 특징을 보인다. 본 연구에서는 효모에서의 cTPx II의 생리학적 기능을 밝히는 연구의 첫 과정으로 cTPx II와 상호 작용하는 단백질을 탐색하였다. Sacchromyces cerevisiae genomic DNA library에서 yeast two-hybrid system을 이용하여 cTPx II와 상호 결합하는 단백질을 탐색하여 그 단백질들의 기능을 연구하여, 궁극적으로 cTPx II의 생리기능을 밝히는데 이 연구의 목적을 두었다.

• Reproductive and Developmental Biology
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• 제35권4호
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• pp.407-414
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• 2011

The development of embryos reconstructed by somatic cell nuclear transfer (SCNT) is dependent upon numerous factors. Central to development is the quality and developmental competence of the recipient cytoplast and the type of the donor nucleus. Typically metaphase of the second meiotic division (MII) has become the cytoplast of choice. Production of a cytoplast requires removal of the recipient genetic material, however, it may remove proteins which are essential for development or reduce the levels of cytoplasmic proteins to influence subsequent reprogramming of the donor nucleus. In this study, enucleation at MII did not affect the activities of either MPF or MAPK kinases. Immunocytochemical staining showed that both Cyclin B1 (MPF) and Erk1/2 (MAPK) were associated with the meiotic spindle of AI/TI oocytes with little staining in the cytoplasm, however, at MII association of both proteins with the spindle had reduced and a greater degree of cytoplasmic distribution was observed. The analysis of oocyte proteins removed during enucleation is a difficult approach to the identification of factors which may be depleted in the cytoplast. This is primarily due to the large numbers of aspirated karyoplasts which would be required for the analysis.

• BMB Reports
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• 제50권7호
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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.

• 약학회지
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• 제33권5호
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• pp.300-307
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• 1989

Expression of transferrin gene in various organs of rat was studied using rat transferrin cDNA. The hybridization method of $[^{35}S]-labeled$ transferrin cDNA with transferrin mRNA in cytoplasmic preparations was used to measure the level of transferrin mRNA. The rat from 15-day old fetus to 21-day old postnatal were employed as an animal model. In the liver, the level of transferrin mRNA increased with increasing age. However, the level of transferrin mRNA in brain was significantly lower than that in liver and the level did not increase with age.

• 미생물학회지
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• 제24권3호
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• pp.270-275
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• 1986

Pseudomonas carboxydovorans와 Acinetobacter sp.l에 존재하는 일산화탄소 산화효소의 세포내 분포양상을 조사 하기 위 하여 엘 산 화탄소를 이 용하여 성장한 세균을 초음파로 파괴하거나 세균의 spheroplast을 만들어 삼투 충격으로 파괴한 후 soluble fraction과 particulate fraction에서의 일산화탄소 산화효소의 환성분포를 조사허여 비교하였다. 세균을 초음파로 파괴하였을 때는 crude cell extract에 존재하면 효소환성의 대부분이 soluble fracttion에서 검출되었다. 그러나 sphe roplas를 삼투충격으로 파괴하였을 때는 효소활성 이 세포막부분에서만 나타났다. 이와 같은 결과는 이 세균들의 일산화탄소 산화효소가 세포막에 느슨하게 붙이 있음을 시사하고 있다.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.258-265
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• 1997

The effects of medium pH and culture temperature on the expression and secretion of inulinase and invertase were investigated with recombinant Saccharomyces cerevisiae cells. These cells were obtained by transformation of 2$\mu$-based plasmids pYI10 and pYS10 which contain Kluyveromyces marxianus inulinase gene (INU1A) and S. cerevisiae invertase gene (SUC2), respectively, in the downstream of GAL1 promoter. The expression level and localization of inulinase and invertase were not affected significantly by the initial medium pH: secretion efficiencies of inulinase and invertase into the medium were about 90% and 60%, respectively, in the pH ranges of 4.0 to 6.5. However, the expression and secretion of both enzymes were strongly dependent on the culture temperature. The highest expression (7.7 units/mL) and secretion (6.7 units/mL) of inulinase were observed at 28$\circ$C and 30$\circ$C. As a consequence of decreased localization of inulinase in the periplasmic space, the secretion efficiency increased from 68% at 20$\circ$C, to 95% at 35$\circ$C,. The total expression level and secretion efficiency of invertase increased from 19 units/mL and 55% at 20$\circ$C to 25 units/mL and 68% at 35$\circ$C, respectively. Irrespective of the culture temperature, the invertase activity in the cellular fraction (periplasmic space and cytoplasmic fractions) was kept constant at around 33-45%.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3627-3630
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• 2012

The epithelial cell adhesion molecule (EpCAM) is a pan-epithelial differentiation antigen that is expressed on almost all carcinomas. However, a role in rat liver carcinogenesis has never been reported previously. Thus, its expression was investigated herein in rat liver tumors induced by diethylnitrosamine (DEN). Twenty male 5-week-old F344 rats were used in this experiment. Mini-osmotic pumps containing doses of 47.5 mg of DEN were inserted into the abdominal cavity of each animal to initiate liver carcinogenesis. All animals were sacrificed at 26 weeks after DEN treatment. At necropsy, hepatic masses were processed for histopathological examination, which revealed forty-four hepatocellular adenomas (HCAs) and twenty hepatocellular carcinomas (HCC). Tumors were immunohistochemically analyzed for EpCAM, proliferating cell nuclear antigen (PCNA) and co-localization of the two. EpCAM expression was mainly detected in hepatic tumor cells, showing a cytoplasmic staining pattern. However, expression was also slightly observed in normally-appearing surrounding hepatic cells. PCNA expression was highly detected in tumor cells, showing nuclear staining. Double staining of EpCAM and PCNA in tumors showed many cells with co-localization. Taken together, EpCAM and PCNA expression were increased in DEN-induced tumors and many tumor cells showed co-expression. It is suggested that EpCAM may increase during DEN-induced tumors, possibly associated with cell proliferation.

• Molecules and Cells
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• 제38권4호
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• pp.343-348
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• 2015

Fiber type-specific programs controlled by the transcription factor MEF2 dictate muscle functionality. Here, we show that HDAC4, a potent MEF2 inhibitor, is predominantly localized to the nuclei in fast/glycolytic fibers in contrast to the sarcoplasm in slow/oxidative fibers. The cytoplasmic localization is associated with HDAC4 hyper-phosphorylation in slow/oxidative-fibers. Genetic reprogramming of fast/glycolytic fibers to oxidative fibers by active CaMKII or calcineurin leads to increased HDAC4 phosphorylation, HDAC4 nuclear export, and an increase in markers associated with oxidative fibers. Indeed, HDAC4 represses the MEF2-dependent, PGC-$1{\alpha}$-mediated oxidative metabolic gene program. Thus differential phosphorylation and localization of HDAC4 contributes to establishing fiber type-specific transcriptional programs.

• The Plant Pathology Journal
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• 제35권1호
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• pp.19-31
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• 2019

Bud rot (BR) is the most devastating disease affecting oil palm (Elaeis guineensis) crops in Colombia. Its causal agent, Phytophthora palmivora, initiates the infection in immature oil palm leaflets producing necrotic lesions, followed by colonization of opportunistic necrotrophs, which increases disease damage. To improve the characterization of the disease, we transformed P. palmivora using Agrobacterium tumefaciens-mediated transformation (ATMT) to include the fluorescent proteins CFP-SKL (peroxisomal localization), eGFP and mRFP1 (cytoplasmic localization). The stability of some transformants was confirmed by Southern blot analysis and single zoospore cultures; additionally, virulence and in vitro growth were compared to the wild-type isolate to select transformants with the greatest resemblance to the WT isolate. GFP-tagged P. palmivora was useful to identify all of the infective structures that are commonly formed by hemibiotrophic oomycetes, including apoplastic colonization and haustorium formation. Finally, we detected cell death responses associated with immature oil palm tissues that showed reduced susceptibility to P. palmivora infection, indicating that these tissues could exhibit age-related resistance. The aim of this research is to improve the characterization of the initial disease stages and generate cell biology tools that may be useful for developing methodologies for early identification of oil palm materials resistant or susceptible to BR.

• Biomolecules & Therapeutics
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• 제30권1호
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• pp.64-71
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• 2022

Norovirus (NV) is the most common cause of viral gastroenteritis, with the potential to develop into a fatal disease in those who are immuno-compromised, and effective vaccines and treatments are still non-existent. In this study, we aimed to elucidate the molecular mechanism of the previously identified NV replication inhibitor utilizing a vinyl-stilbene backbone, AC-1858. First, we confirmed the inhibition of the NV RNA replication by a structural analog of AC-1858, AC-2288 with its exclusive cytoplasmic sub-cellular localization. We further validated the induction of one specific host factor, the phosphorylated form of heat shock factor (HSF)-1, and its increased nuclear localization by AC-1858 treatment. Finally, we verified the positive and negative impact of the siRNA-mediated downregulation and lentivirus-mediated overexpression of HSF-1 on NV RNA replication. In conclusion, these data suggest the restrictive role of the host factor HSF-1 in overall viral RNA genome replication during the NV life cycle.