• Molecules and Cells
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• v.42 no.11
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• pp.739-746
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• 2019

Significant knowledge about the pathophysiology of Alzheimer's disease (AD) has been gained in the last century; however, the understanding of its causes of onset remains limited. Late-onset AD is observed in about 95% of patients, and APOE4-encoding apolipoprotein E4 (ApoE4) is strongly associated with these cases. As an apolipoprotein, the function of ApoE in brain cholesterol transport has been extensively studied and widely appreciated. Development of new technologies such as human-induced pluripotent stem cells (hiPSCs) and CRISPR-Cas9 genome editing tools have enabled us to develop human brain model systems in vitro and readily manipulate genomic information. In the context of these advances, recent studies provide strong evidence that abnormal cholesterol metabolism by ApoE4 could be linked to AD-associated pathology. In this review, we discuss novel discoveries in brain cholesterol dysregulation by ApoE4. We further elaborate cell type-specific roles in cholesterol regulation of four major brain cell types, neurons, astrocytes, microglia, and oligodendrocytes, and how its dysregulation can be linked to AD pathology.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1305-1310
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• 2021

Shikimate is a key high-demand metabolite for synthesizing valuable antiviral drugs, such as the anti-influenza drug, oseltamivir (Tamiflu). Microbial-based strategies for shikimate production have been developed to overcome the unstable and expensive supply of shikimate derived from traditional plant extraction processes. In this study, a microbial cell factory using Corynebacterium glutamicum was designed to overproduce shikimate in a fed-batch culture system. First, the shikimate kinase gene (aroK) responsible for converting shikimate to the next step was disrupted to facilitate the accumulation of shikimate. Several genes encoding the shikimate bypass route, such as dehydroshikimate dehydratase (QsuB), pyruvate kinase (Pyk1), and quinate/shikimate dehydrogenase (QsuD), were disrupted sequentially. An artificial operon containing several shikimate pathway genes, including aroE, aroB, aroF, and aroG were overexpressed to maximize the glucose uptake and intermediate flux. The rationally designed shikimate-overproducing C. glutamicum strain grown in an optimized medium produced approximately 37.3 g/l of shikimate in 7-L fed-batch fermentation. Overall, rational cell factory design and culture process optimization for the microbial-based production of shikimate will play a key role in complementing traditional plant-derived shikimate production processes.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.278-286
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• 2021

Efficient in vitro regeneration system is essential for the successful crop breeding of soybean (Glycine max (L.) Merr.) using the new biotechnology. The genotype of donor plants strongly influences the establishment of tissue culture system. Therefore, the screening of genotypes with excellent tissue culture ability is very important for soybean genetic improvement. In this study, we report the tissue culture efficiency of 21 soybean cultivars belong to Korean soybean core-collection and two foreign cultivars (Jack and Maverick). The Kwangan, Anpyeong and Seonam are share close genetic relationship in 21 cultivars and these three cultivars were observed the high frequency of germination and regeneration. Furthermore, the high tissue culture abilities were also observed in the Williams 82 used in reference genome sequencing and the two foreign cultivars. The transformation of pBAtc:tRNA with bar gene was performed by Agrobacterium tumefaciens in the cultivars with high tissue culture ability. Transformation of the bar gene was identified by PCR analysis in Kwangan, Pungwon, Seonam, and Maverick. Our results provide useful information for the breeding of various soybean cultivars by plant biotechnology such as, genome editing.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.394-401
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• 2016

Recently, the clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (CRISPR/Cas9) system, a genome editing technology, was shown to be versatile in treating several antibiotic-resistant bacteria. In the present study, we applied the CRISPR/Cas9 technology to kill extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. ESBL bacteria are mostly multidrug resistant (MDR), and have plasmid-mediated antibiotic resistance genes that can be easily transferred to other members of the bacterial community by horizontal gene transfer. To restore sensitivity to antibiotics in these bacteria, we searched for a CRISPR/Cas9 target sequence that was conserved among >1,000 ESBL mutants. There was only one target sequence for each TEM- and SHV-type ESBL, with each of these sequences found in ~200 ESBL strains of each type. Furthermore, we showed that these target sequences can be exploited to re-sensitize MDR cells in which resistance is mediated by genes that are not the target of the CRISPR/Cas9 system, but by genes that are present on the same plasmid as target genes. We believe our Re-Sensitization to Antibiotics from Resistance (ReSAFR) technology, which enhances the practical value of the CRISPR/Cas9 system, will be an effective method of treatment against plasmid-carrying MDR bacteria.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.220-239
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• 2021

Grasses (Poaceae) belong to the biggest plant family among angiosperms and it cover around 20% of the earth's surface. The members of this family are mostly utilized as food resources by humans and animals but they are also valuable in terms of evolution and ecology. The member of the subfamily Pooideae represents, temperate grasses, and includes a number of economically important crops and belongs to the clade BOP (including the subfamilies Bambooideae, Oryzeae, and Pooideae). This subfamily is the largest among all grass families. The special features of this subfamily are cold acclimation and vernalization. The members of Pooideae subfamily with the aforementioned special features are thought to have evolved in the Cenozoic era when the temperature on earth started to cool down, which triggered the diversification of this subfamily through adaptation to cold weather. The agricultural origin of wheat, barley, oat, and rye is attributed to fertile crescent and thereafter they were domesticated through Neolithic evolution. The history of domestication of each Pooideae crop is distinct and is based on their purpose. Recently, breeding of these crops is performed differently due to the development of new technologies such as genomics and genome editing. This review article summarizes the evolutionary history of the members of the subfamily Pooideae and use of pre-existing information for future breeding efforts.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.210-216
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• 2021

This study aimed to enhance ethanol productivity of Saccharomyces cerevisiae through genome editing using CRISPR/CAS9. To increase ethanol productivity, ACC1, ELO1, and OLE1 were overexpressed in S. cerevisiae using the CRISPR/CAS9 system. The strains overexpressing ACC1, ELO1, and OLE1 survived up to 24 h in YPD medium supplemented with 18% ethanol. Moreover, the ethanol yields in strains overexpressing ACC1 (428.18 mg ethanol/g glucose), ELO1 (416.15 mg ethanol/g glucose), and OLE1 (430.55 mg ethanol/g glucose) were higher than those in the control strains (400.26 mg ethanol/g glucose). In conclusion, the overexpression of these genes increased the viability of S. cerevisiae at high ethanol concentrations and the ethanol productivity without suppressing glucose consumption.

• Nutrition Research and Practice
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• v.13 no.5
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• pp.425-433
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• 2019

BACKGROUND/OBJECTIVES: The International Agency for Research on Cancer defined alcohol beverages and acetaldehyde derived from alcoholic beverages as a Group 1 carcinogen to humans. However, the association between alcohol consumption and gastric cancer risk has been controversial in Korean. We assessed the relationship between alcohol consumption and gastric cancer risk in Korea through a case-control study. SUBJECTS/METHODS: From 2 hospitals, a total of 316 cases with gastric cancer (208 men, 108 women) were selected and matched to 316 controls by sex and age (${\pm}5years$) during the same duration. The current status, frequency, and amount of alcohol consumption for a year three years ago were assessed by trained interviewers. RESULTS: Alcohol consumption status and frequency did not show any significant association with gastric cancer risk. However, high alcohol consumption (${\geq}20g/day$ for women or ${\geq}40g/day$ for men) significantly increased the risk of gastric cancer (odds ratio (OR) 1.73; 95% confidence interval (CI) 1.05-2.85). Gastric cancer risk was strongly positively associated with alcohol consumption of ${\geq}20g/day$, especially in women (OR 5.62; 95% CI 1.32-23.81). CONCLUSION: The results from this study suggest that excessive alcohol consumption rather than the current status or frequency of alcohol consumption contributes to the increased risk of gastric cancer, especially in women.

• BMB Reports
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• v.55 no.10
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• pp.488-493
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• 2022

The specific pair of heat shock protein 70 (Hsp70) and Hsp40 constitutes an essential molecular chaperone system involved in numerous cellular processes, including the proper folding/refolding and transport of proteins. Hsp40 family members are characterized by the presence of a conserved J-domain (JD) that functions as a co-chaperone of Hsp70. Tumorous imaginal disc 1 (Tid1) is a tumor suppressor protein belonging to the DNAJA3 subfamily of Hsp40 and functions as a co-chaperone of the mitochondrial Hsp70, mortalin. In this work, we performed nuclear magnetic resonance spectroscopy to determine the solution structure of JD and its interaction with the glycine/phenylalanine-rich region (GF-motif) of human Tid1. Notably, Tid1-JD, whose conformation was consistent with that of the DNAJB1 JD, appeared to stably interact with its subsequent GF-motif region. Collectively with our sequence analysis, the present results demonstrate that the functional and regulatory mode of Tid1 resembles that of the DNAJB1 subfamily members rather than DNAJA1 or DNAJA2 subfamily proteins. Therefore, it is suggested that an allosteric interaction between mortalin and Tid1 is involved in the mitochondrial Hsp70/Hsp40 chaperone system.

• Journal of Genetic Medicine
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• v.20 no.1
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• pp.6-14
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• 2023

Fabry disease (FD), a rare X-linked lysosomal storage disorder, is caused by mutations in the α-galactosidase A gene gene encoding α-galactosidase A (α-Gal A). The functional deficiency of α-Gal A results in progressive accumulation of neutral glycosphingolipids, causing multi-organ damages including cardiac, renal, cerebrovascular systems. The current treatment is comprised of enzyme replacement therapy (ERT), oral pharmacological chaperone therapy and adjunctive supportive therapy. ERT has been introduced 20 years ago, changing the outcome of FD patients with proven effectiveness. However, FD patients have many unmet needs. ERT needs a life-long intravenous therapy, inefficient bio-distribution, and generation of anti-drug antibodies. Migalastat, a pharmacological chaperone, augmenting α-Gal A enzyme activity only in patients with mutations amenable to the therapy, is now available for clinical practice. Furthermore, these therapies should be initiated before the organ damage becomes irreversible. Development of novel drugs aim at improving the clinical effectiveness and convenience of therapy. Clinical trial of next generation ERT is underway. Polyethylene glycolylated enzyme has a longer half-life and potentially reduced antigenicity, compared with standard preparations with longer dosing interval. Moss-derived enzyme has a higher affinity for mannose receptors, and seems to have more efficient access to podocytes of kidney which is relatively resistant to reach by conventional ERT. Substrate reduction therapy is currently under clinical trial. Gene therapy has now been started in several clinical trials using in vivo and ex vivo technologies. Early results are emerging. Other strategic approaches at preclinical research level are stem cell-based therapy with genome editing and systemic mRNA therapy.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.168-176
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• 2023

Silicon (Si) has the potential to improve plant growth and stress tolerance. The study aimed to explore Si-involving plant responses and molecular characterization of different Si-responsive genes in alfalfa. In this study, the exogenous supplementation of Si enhanced plant growth, and biomass yield. Si-acquisition in alfalfa root and shoot was higher in Si-supplemented compared to silicon deficient (-Si) plants, implying Si-acquisition has beneficial on alfalfa plants. As a consequence, the quantum efficiency of photosystem II (Fv/Fm) was significantly increased in silicon-sufficient (+Si) plants. The quantitative gene expression analysis exhibited a significant upregulation of the Lsi1, Lsi2, Lsi3, NIP5;1, and NIP6;1 genes in alfalfa roots, while BOR1, BOR4, NIP2, and NIP3 showed no significant variation in their expression. The MEME results further noticed the association of four motifs related to the major intrinsic protein (MIP). The interaction analysis revealed that NIP5;1 and Lsi1 showed a shared gene network with NIP2, BOR1, and BOR4, and Lsi2, Lsi3 and NIP3-1, respectively. These results suggest that members of the major intrinsic proteins (MIPs) family especially Lsi1, Lsi2, Lsi3, NIP5;1, and NIP6;1 genes helped to pass water and other neutral solutes through the cell membrane and those played significant roles in Si uptake and transport in plants. Together, these insights might be useful for alfalfa breeding and genome editing approaches for alfalfa improvement.