• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.429-433
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• 2000

Giardia lamblia, a human pathogen causing outbreaks of diarrhea, recently became a focus of great concerns in the fields of both medical and environmental microbioloty. To develop the experimental tools to study giardiasis, encystation, one of the major processes in its life cycle, was reconstituted by inducing an axenic culture of a flagellated form of G. lamblia into a cyst from under high concentration of bile and alkaline pH condition. The successful induction was confirmed by Northern analysis of resulting increased expression of the CWPl gene encoding the cyst wall protein 1. An examination of the encystation process with SEM (scanning electron microscopy) and TEM (transmission electron microscopy) revealed that the trophozoite, a flagellate with a bilateral symmetry, was transformed to a cyst form with an oval-shape and defined filamentous wall. The encystation was found to cause a disappearance of the flagella and an invagination of the adhesive disc. An extensive formation of rER (rough endoplasmic reticulum) was observed after 24h of induction, indication an active synthesis and export of proteins during this process. The vital staining of the invitro-induced systs showed that most cysts maintained their viability.

• BMB Reports
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• 제49권12호
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• pp.651-652
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• 2016

EphA2 has been implicated in amplifying ErbB2 tumorigenic signaling. One protein that interacts with EphA2 is the Anks1a PTB adaptor. However, the precise role of Anks1a in EphA2-mediated tumorigenesis is unclear. We demonstrated that Anks1a localizes to the ER upon phosphorylation and that the Ankyrin repeats and PTB of Anks1a bind to EphA2 and Sec23, respectively. Thus, Anks1a facilitates the selective packaging of EphA2 into COPII vesicles. Additionally, Anks1a knockout mice, a phenocopy of EphA2 knockout mice, exhibited markedly reduced ErbB2-induced breast tumorigenesis. Strikingly, ErbB2 did not localize to the cell surface following Anks1a knockdown in primary mammary tumor cells over-expressing ErbB2. Importantly, EphA2 was critical for stabilizing ErbB2 through complex formation, but its interaction with Anks1a also facilitated ErbB2 loading into COPII carriers. These findings suggest a novel role for Anks1a in the molecular pathogenesis of breast tumors and possibly other human diseases.

• BMB Reports
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• 제51권9호
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• pp.425-426
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• 2018

As highly conserved signaling cascades of multicellular organisms, Wnt and Hippo pathways control a wide range of cellular activities, including cell adhesion, fate determination, cell cycle, motility, polarity, and metabolism. Dysregulation of those pathways are implicated in many human diseases, including cancer. Similarly to ${\beta}-catenin$ in the Wnt pathway, the YAP transcription co-activator is a major player in Hippo. Although the intracellular dynamics of YAP are well-known to largely depend on phosphorylation by LATS and AMPK kinases, the molecular effector of YAP cytosolic translocation remains unidentified. Recently, we reported that the Dishevelled (DVL), a key scaffolding protein between canonical and non-canonical Wnt pathway, is responsible for nuclear export of phosphorylated YAP. The DVL is also required for YAP intracellular trafficking induced by E-cadherin, ${\alpha}-catenin$, or metabolic stress. Note that the p53/LATS2 and LKB1/AMPK tumor suppressor axes, commonly inactivated in human cancer, govern the reciprocal inhibition between DVL and YAP. Conversely, loss of the tumor suppressor allows co-activation of YAP and Wnt independent of epithelial polarity or contact inhibition in human cancer. These observations provide novel mechanistic insight into (1) a tight molecular connection merging the Wnt and Hippo pathways, and (2) the importance of tumor suppressor contexts with respect to controlled proliferation and epithelial polarity regulated by cell adhesion.

• The Korean Journal of Physiology and Pharmacology
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• 제22권2호
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• pp.155-162
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• 2018

3-(2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP), a competitive N-methyl-D-aspartate (NMDA) receptor antagonist, produces rapid antidepressant-like effects in animal models of depression. However, the molecular mechanisms underlying these behavioral actions remain unknown. Here, we demonstrate that CPP rapidly stimulates histone deacetylase (HDAC) 5 phosphorylation and nuclear export in rat hippocampal neurons. These effects are accompanied by calcium/calmodulin kinase II (CaMKII) and protein kinase D (PKD) phosphorylation. Behavioral experiments revealed that viral-mediated hippocampal knockdown of HDAC5 blocked the antidepressant effects of CPP in stressed animals. Taken together, our results imply that CPP acts via HDAC5 and suggest that HDAC5 is a common regulator contributing to the antidepressant actions of NMDA receptor antagonists such as CPP.

• 미생물학회지
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• 제26권4호
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• pp.291-297
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• 1988

신호배열 돌연변이인 rbsB 103는 전구체 리보스 결합단백질을 세포질내에 축적시키고, rbsB 106 복귀유전자는 이 전구체를 숙성 가능하게 하여 페리플라슴으로 수송되게 한다.(Iida el at., 1985, Park, el at., 1988). 본고에서는 rbsB 유전자의 세 allele, rbsB, rbsB 103와 rbsB 106를 이들이 코딩하는 단백질을 대량생산 하그l자 람다 P 프로모터 조절하에 클론하고 나아가서 다섯종의 단백질을 순수정제하였다.. 전구체 단백질의 pI는 8.0, 숙성단백질의 $P_{L}$는 7.5임을 밝혔다. 순수정제된 단백질의 아마노 말단의 아미노산 배열을 결정하여 DNA 염기서열로부터 밝혀진 아미노산 변화를 확인하였다.

• Animal cells and systems
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• 제16권3호
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• pp.173-182
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• 2012

The p53 protein plays a pivotal role in tumor suppression. The cellular level of p53 is normally kept low by proteasome-mediated degradation, allowing cell cycle progression and cell proliferation. Under stress conditions, such as DNA damage, p53 is stabilized and activated through various post-translational modifications of itself as well as of its regulatory proteins for induction of the downstream genes responsible for cell cycle arrest, DNA repair, and apoptosis. Therefore, the level of p53 should be tightly regulated for normal cell growth and for prevention of the accumulation of mutations in DNA under stress conditions, which otherwise would lead to tumorigenesis. Since the discovery of Mdm2, a critical ubiquitin E3 ligase that destabilizes p53 in mammalian cells, nearly 20 different E3 ligases have been identified and shown to function in the control of stability, nuclear export, translocation to chromatin or nuclear foci, and oligomerization of p53. So far, a large number of excellent reviews have been published on the control of p53 function in various aspects. Therefore, this review will focus only on mammalian ubiquitin E3 ligases that mediate proteasome-dependent degradation of p53.

• Journal of Animal Science and Technology
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• 제44권3호
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• pp.361-368
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• 2002

한국산 수출용 냉동 돈육의 품질 특성을 조사하기 위해 수출 육가공업체 3개소(Ⅰ . Ⅱ . Ⅲ)의 냉동 돈육 등심을 -20$^{\circ}C$에서 40일간 냉동 저장한 후 각 수출업체별 시료의 pH, 일반성분, 이화학적 특성, 관능적 특성, 선도 및 미생물 변화를 조사하였으며, 그 결과는 다음과 같다. 일반성분에서 조단백질은 Ⅱ업체 시료가 유의적(p<0.05)으로 높았고, 조회분은 Ⅰ업체 시료가 유의적으로 높았다. 육질 특성에서 pH와 보수성은 Ⅱ업체 시료가 유의적으로 높았으며, 전단력과 가열 감량은 Ⅱ업체 시료가 가장 낮았다. 총세균 수는 3.04${\sim}$3.75 log cfu/$cm^2$, 대장균군 수는 0.37${\sim}$1.32 log cfu/$cm^2$ 수준이었으며, TBARS 값은 평균 0.35${\sim}$0.38 mg malonaldehyde/kg sample 수준으로 비교적 낮았다. 척도묘사평가법을 이용한 관능검사 결과 세 업체 모두 평가 항목간에 유의적인 차이가 없는 것으로 나타났다.

• 생명과학회지
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• 제24권5호
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• pp.588-593
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• 2014

본 논문은 RLIP76 단백질이 암, 종양 혈관 신생 및 그 치료에 미치는 중요성을 보고함에 있다. 암의 연구에 있어서, 종양의 혈관 신생을 억제시키는 인자와 영향을 끼치는 인자를 밝혀내는 것은 암의 억제와 치료를 위한 분자 생물학적 기전에 중대한 영향을 미친다. 최근 연구에서, RLIP76 단백질이 혈관 신생에 영향을 끼치는 역할을 발견하였다. RLIP76 제거 마우스의 종양은 일반 종양과 비교하여 혈관의 크기가 작으며, 가늘고, 그 혈관의 수가 적고 길이가 짧은 것으로 보고되고 있다. 게다가, Matrigel plugs을 이용한 혈관 신생 실험에서, RLIP76이 제거된 마우스에서는 혈관 생성이 억제 되었으나, 일반 마우스에서는 혈관이 생성되었다. 또한, 혈관세포를 이용한 in vitro 실험에 있어서, proliferation, migration 및 cord formation 모두가 RLIP76에 의해서 조절되었다. 일반적으로 RLIP76은 대부분의 인간 조직과 종양에서 발현되며, 약의 저항 기전 연구에 이용되고 있기도 한다. 또한, 이RLIP76은 small GTPase R-Ras와 상호작용을 통하여 세포 spreading 및 migration에 관여하고 있다. 이러한 결과는 RLIP76와 암 연구의 중요성을 보고하고 있으며, 혈관 세포의 기능의 기전 및 종양의 혈관 신생을 위한 RLIP76 단백질의 중요성을 알리고 있고, RLIP76의 추가적인 연구를 통하여 종양의 혈관 신생의 기전을 밝히는 것이 필요함을 제안하는 바이다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1612-1612
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• 2001

The production of grain for export and domestic use is one of Australia's most important agricultural industries, and the NIR technique has been used extensively over many years for the routine monitoring of grain quality, particularly moisture and protein content. Because most Australian grain is intended for human food production, the determinants of grain quality for livestock feed, apart from protein, have been largely ignored. However the increasing use of grain for feeding to pigs, poultry, beef cattle and dairy cows has led to an important national research project entitled “Premium Grains for Livestock”. Two of the objectives of this project are to determine the compositional and functional characteristics of grains which influence their nutritional quality for the various classes of livestock, and to adopt rapid and objective analytical tests for these quality criteria. NIR has been used in this project firstly to identify a set of grain samples from a large population of breeders' lines which showed a wide spectral variation, and hence a potentially wide variation in nutritional value. The selected samples were not only subjected to an extensive array of chemical, physical and in vitro analyses, but also were grown out to produce sufficient quantities of grain to feed to animals in vivo studies. Additional grains were also strategically selected from farms in order to include the effect of weather damage, such as rain, drought and frost. In this study to date, NIR calibrations have been derived or attempted, on both ground and whole grains, for in vivo dry matter digestibility (DMD), pepsin-cellulase dry matter disappearance, protein, fat, acid detergent fibre, neutral detergent fibre, starch, in sacco DMD and in vitro assays to simulate starch digestion in the lumen and small intestine. Results so far indicate high calibration accuracy for chemical components (SECV 0.3 to 2.6%) and very promising statistics for in vivo DMD (SECV 1.8, $R^2$ 0.93, SD 7.0, range 61.9 to 92.3, n=60). There appears to be some potential for NIR to estimate some in vitro properties, depending upon the accuracy of reference methods and appropriate sample populations. Current work is in progress to extend the range of grains with in vivo DMD values (a very laborious and expensive process) and to increase the robustness of the various NIR calibrations, with the aim of implementing uniform testing procedures for nutritional value of grains throughout Australia.

• Asian-Australasian Journal of Animal Sciences
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• 제31권7호
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• pp.927-932
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• 2018

The demand for beef as a protein source is increasing worldwide, although in most countries beef accounts for considerably less than half of total meat consumption. Beef also provides a highly desirable eating experience in developed countries and, increasingly, in developing countries. The sustainability of beef production has different meanings in the various geographical and socio-economic regions of the world. Natural resources including land mass and uses, rainfall and access to livestock feed, and the robustness of the economy are major determinants of the perception of beef sustainability. In this overview of the 2016 International Symposium on "Future Beef in Asia" and this subsequent Special Edition of the Asian-Australasian Journal of Animal Sciences on "Current Situation and Future Prospects for Global Beef Production", the contributions have been grouped into the following categories: Countries in Southeast Asia; Europe; and Countries producing highly marbled beef for export and/or domestic consumption. They also include reference to Special Topics including marbled beef production, and use of "omics" technologies to enhance beef quality assurance. Among these broad categories, notable differences exist across countries in the production and marketing of beef. These reflect differences in factors including natural resource availability and climate, population size, traditional culture and degree of economic development including industrial and technological developments. We trust that the International Symposium and this Special Edition on Current Situation and Future Prospects for Global Beef Production, the contents of which that are briefly summarized in this paper, will serve as a valuable resource for the livestock industries, researchers and students with an interest in enhancing the prospects for sustainable, efficient beef production that satisfies the growing size and complexity of consumer demands and markets for beef.