• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1059-1070
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• 2007

Prion diseases, often called transmissible spongiform encephalopathies (TSEs), are infectious diseases that accompany neurological dysfunctions in many mammalian hosts. Prion diseases include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE, "mad cow disease") in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elks. The cause of these fatal diseases is a proteinaceous pathogen termed prion that lacks functional nucleic acids. As demonstrated in the BSE outbreak and its transmission to humans, the onset of disease is not limited to a certain species but can be transmissible from one host species to another. Such a striking nature of prions has generated huge concerns in public health and attracted serious attention in the scientific communities. To date, the potential transmission of prions to humans via foodborne infection and iatrogenic routes has not been alleviated. Rather, the possible transmission of human to human or cervids to human aggravates the terrifying situation across the globe. In this review, basic features about prion diseases including clinical and pathological characteristics, etiology, and transmission of diseases are described. Based on recently accumulated evidences, the molecular and biochemical aspects of prions, with an emphasis on the molecular interactions involved in prion conversion that is critical during prion replication and pathogenesis, are also addressed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.4
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• pp.341-346
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• 2014

Transmissible spongiform encephalopathies (TSEs), also termed prion diseases, are a threat to food safety and to human and animal health. Variant Creutzfeldt-Jakob disease (vCJD) in humans is caused by the consumption of meat contaminated with bovine spongiform encephalopathy (BSE, mad cow disease). The BSE epidemic in the United Kingdom was shown to be related with the extensive use of BSE-contaminated meat-and-bone meal (MBM) and bovine offal. Many countries worldwide use MBM, as well as meat from cows, for aquaculture feed. This raises concerns about the safety of farmed fish, a major protein source for humans. The present work reviews recent studies on fish prion protein and the transmissibility of mammalian prion agents to fish, providing insights into the future direction of fish prion research.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1657-1660
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• 2016

Prion diseases are incurable neurodegenerative disorders. Our previous study demonstrated that polylysine was effective in prolonging the incubation period in a rodent model and in alleviating the scrapie prion protein (PrP^Sc) burden in the brain at the terminal stage of the disease. Here, we report that intraperitoneal administration of polylysine suppresses the accumulation of prions in the spleen during the early stages of the disease. This study supports the congruence of PrP^Sc inhibition by polylysine in both the spleen and brain.

• BMB Reports
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• v.40 no.5
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• pp.662-669
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• 2007

Although the function of cellular prion protein (PrP$^C$) and the pathogenesis of prion diseases have been widely described, the mechanisms are not fully clarified. In this study, increases of the portion of non-glycosylated prion protein deposited in the hamster brains infected with scrapie strain 263K were described. To elucidate the pathological role of glycosylation profile of PrP, wild type human PrP (HuPrP) and two genetic engineering generated non-glycosylated PrP mutants (N181Q/N197Q and T183A/T199A) were transiently expressed in human astrocytoma cell line SF126. The results revealed that expressions of non-glycosylated PrP induced significantly more apoptosis cells than that of wild type PrP. It illustrated that Bcl-2 proteins might be involved in the apoptosis pathway of non-glycosylated PrPs. Our data highlights that removal of glycosylation of prion protein provokes cells apoptosis.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3553-3554
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• 2011

• BMB Reports
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• v.56 no.12
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• pp.645-650
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• 2023

Numerous studies have investigated the cellular prion protein (PrP^C) since its discovery. These investigations have explained that its structure is predominantly composed of alpha helices and short beta sheet segments, and when its abnormal scrapie isoform (PrPSc) is infected, PrPSc transforms the PrP^C, leading to prion diseases, including Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy in cattle. Given its ubiquitous distribution across a variety of cellular types, the PrP^C manifests a diverse range of biological functions, including cell-cell adhesion, neuroprotection, signalings, and oxidative stress response. PrP^C is also expressed in immune tissues, and its functions in these tissues include the activation of immune cells and the formation of secondary lymphoid tissues, such as the spleen and lymph nodes. Moreover, high expression of PrP^C in immune cells plays a crucial role in the pathogenesis of prion diseases. In addition, it affects inflammation and the development and progression of cancer via various mechanisms. In this review, we discuss the studies on the role of PrP^C from various immunological perspectives.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.628-631
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• 2009

Recent social interests on mad cow disease and Creutzfelt-Jacob disease lead researcher' focus onto pathogenic prion proteins causing those diseases. The purpose of this study is to introduce a novel method for micromolecular level quantification of PrP 106-126 peptide, which is a part of prion protein. Fluorescamine has been chosen due to its fluorescence emission characteristics upon reaction with primary amines and Alpha-imager is used to detect the intensity of fluorescence. We succeeded in setting optimal conditions for quantification of PrP 106-206, amyloidogenic prion peptide, at micromolecular level. This study will contribute to identify prion protein aggregation inhibitor and develop new prion protein drug.

• BMB Reports
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• v.42 no.7
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• pp.444-449
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• 2009

Different neurodegenerative disorders like prion disease, is caused by protein misfolding conformers. Reverse-transfected cytosolic prion protein (PrP) and PrP expressed in the cytosol have been shown to be neurotoxic. To investigate the possible mechanism of neurotoxicity due to accumulation of PrP in cytosol, a PrP mutant lacking the signal and GPI (CytoPrP) was introduced into the SH-SY5Y cell. MTT and trypan blue assays indicated that the viability of cells expressing CytoPrP was remarkably reduced after treatment of MG-132. Obvious apoptosis phenomena were detected in the cells accumulated with CytoPrP, including loss of mitochondrial transmembrane potential, increase of caspase-3 activity, more annexin V/PI-double positive-stained cells and reduced Bcl-2 level. Moreover, DNA fragmentation and TUNEL assays also revealed clear evidences of late apoptosis in the cells accumulated CytoPrP. These data suggest that the accumulation of CytoPrP in cytoplasm may trigger cell apoptosis, in which mitochondrial relative apoptosis pathway seems to play critical role.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.32-38
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• 2017

Prion is a group of the proteins known for its infection mechanisms of Creutzfeldt-Jakob disease (CJD) and other diseases. Solved structures and proven biological roles of fungal prions add tremendous potential to conducting computational simulations. Our research focuses on the binding dynamics of HET-s(218-289), one of the heterokaryon fungal prion originated from Podospora anserina, by calculating the binding free energy using umbrella sampling at 300 K. The binding free energy calculated was $-54.5kcal\;mol^{-1}$, relatively similar to the binding energy of other amyloid fibrils. The simulation result suggests the thermodynamic properties of ${\beta}$-solenoid of HET-s prion and its similarity in dissociation pathways compared to amyloids.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.91-96
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• 2015

Prions are proteinaceous infectious particles that cause neurodegenerative diseases, such as scrapie in sheep, bovine spongiform encephalopathy in cattle and Creutzfeldt-Jakob disease (CJD) in humans. Although the detailed process, regarding the abnormal conversion of prion proteins (PrP), remains to be fully elucidated, a number of environmental factors appear to affect the formation of misfolded PrP, termed PrP^Sc. Because oceanic algae contain mycosporine-like amino acids (MAAs), which exhibit cellular defensive activities under a variety of stress conditions, we investigated the level of PrP^Sc in prion-infected neuroblastoma cells using mycosporine-glycine, porphyra-334 and shinorine. When judged by the level of protease-resistant PrP^Sc in western blots, porphyra-334 and shinorine increased the level of PrP^Sc in cells, but mycosporine-glycine did not. The current results indicate that the MAAs tested in this study enhance the formation of PrP^Sc.