103 results on '"Sang-Kyu Lee"'
Search Results
2. Antibody responses after vaccination against equine influenza virus in the Republic of Korea in 2019
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Soo dong Cho, Bang-Hun Hyun, Seo Young Moon, Min-Ji Kim, Sang Kyu Lee, Suyeong Yun, Choi-Kyu Park, Hyoung seok Yang, In-Ohk Ouh, Hyeonhae Choi, and Yoon-Hee Lee
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Vaccination ,Antibody response ,Equine influenza virus ,Horse ,Biology ,Virology - Published
- 2020
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3. New records of two spider crabs (Decapoda, Brachyura, Majidae) from Korea
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Sang-kyu Lee, Jung Nyun Kim, Won Kim, and Sang-Hui Lee
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Carcinology ,Spider ,Geography ,biology ,Decapoda ,Majidae ,Zoology ,Animal Science and Zoology ,Aquatic Science ,biology.organism_classification - Abstract
Two species of the family Majidae, Sakaija japonica (Rathbun, 1932) and Schizophroida simodaensis Sakai, 1933, are herein newly reported from Korean waters. These are also the first records of Sakaija Ng & Richer de Forges, 2015 and Schizophroida Griffin & Tranter, 1986 in Korea. There are currently 14 majoid species from nine genera in Korea. Herein, diagnoses of Sakaija japonica and Schizophroida simodaensis are provided together with illustrations.
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- 2020
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4. Molecular Prevalence of Equine Parvovirus-Hepatitis in the Sera of Clinically Healthy Horses in South Korea
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Dongsun Park, Sang-Kyu Lee, and Inhyung Lee
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Hepatitis ,Genetic diversity ,Veterinary medicine ,General Veterinary ,biology ,Phylogenetic tree ,Parvovirus ,Potential risk ,molecular prevalence ,EqPV-H ,phylogenetic analysis ,prevalence ,biology.organism_classification ,Serum samples ,medicine.disease ,Article ,law.invention ,law ,South Korea ,SF600-1100 ,medicine ,Polymerase chain reaction - Abstract
Equine parvovirus-hepatitis (EqPV-H) causes equine hepatitis. The prevalence of EqPV-H in healthy horses has been reported in the United States, China, Germany, and Austria. The present study determined the prevalence of EqPV-H in the sera of clinically healthy horses in South Korea to identify the potential factors for infection and examine the genetic diversity of EqPV-H DNA sequences through comparison with foreign strains. Serum samples collected from 321 horses were tested for EqPV-H using non-structural protein 1 (NS1)-specific polymerase chain reaction. The associations of EqPV-H infection with sex, age, aspartate aminotransferase and γ-glutamyl transferase levels, and race performance were analyzed. Fourteen samples tested positive for EqPV-H (4.4%, 14/321), and EqPV-H infection was associated with sex (p = 0.006) and performance (p = 0.049). In both EqPV-H-positive and control horses, liver-specific biochemical analytes were within the normal ranges. Phylogenetic analyses based on the partial sequences of EqPV-H NS1 revealed that the Korean EqPV-H isolates shared approximately 98.7–100% similarity. Of these, 11 Korean isolates shared high similarity with strains from the United States, Germany, and China, and the remaining three strains were distinct in phylogenetic analyses. The present study describes the current molecular prevalence, potential risk factors, and genetic diversity of Korean EqPV-H.
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- 2021
5. Rice β-glucosidase Os12BGlu38 is required for synthesis of intine cell wall and pollen fertility
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Guorun Qu, Chanhui Lee, Dabing Zhang, Jong-Seong Jeon, Yu-Jin Kim, Bancha Mahong, Manatchanok Kongdin, Su-Hyeon Shim, Sang-Kyu Lee, and James R. Ketudat Cairns
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Oryza sativa ,Physiology ,beta-Glucosidase ,Mutant ,Stamen ,Wild type ,food and beverages ,Oryza ,Plant Science ,Cutin ,Biology ,medicine.disease_cause ,Cell wall ,medicine.anatomical_structure ,Fertility ,Biochemistry ,Cell Wall ,Gene Expression Regulation, Plant ,Pollen ,medicine ,Gamete ,Plant Proteins - Abstract
Glycoside hydrolase family1 β-glucosidases play a variety of roles in plants, but their in planta functions are largely unknown in rice (Oryza sativa). In this study, the biological function of Os12BGlu38, a rice β-glucosidase, expressed in bicellular to mature pollen, was examined. Genotype analysis of progeny of the self-fertilized heterozygous Os12BGlu38 T-DNA mutant, os12bglu38-1, found no homozygotes and a 1:1 ratio of wild type to heterozygotes. Reciprocal cross analysis demonstrated that Os12BGlu38 deficiency cannot be inherited through the male gamete. In cytological analysis, the mature mutant pollen appeared shrunken and empty. Histochemical staining and TEM showed that mutant pollen lacked intine cell wall, which was rescued by introduction of wild-type Os12BGlu38 genomic DNA. Metabolite profiling analysis revealed that cutin monomers and waxes, the components of the pollen exine layer, were increased in anthers carrying pollen of os12bglu38-1 compared with wild type and complemented lines. Os12BGlu38 fused with green fluorescent protein was localized to the plasma membrane in rice and tobacco. Recombinant Os12BGlu38 exhibited β-glucosidase activity on the universal substrate p-nitrophenyl β-d-glucoside and some oligosaccharides and glycosides. These findings provide evidence that function of a plasma membrane-associated β-glucosidase is necessary for proper intine development.
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- 2021
6. Action of Multiple Rice β-Glucosidases on Abscisic Acid Glucose Ester
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James R. Ketudat Cairns, Su-Hyeon Shim, Manatchanok Kongdin, Sang-Kyu Lee, Bancha Mahong, and Jong-Seong Jeon
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0106 biological sciences ,0301 basic medicine ,Arabidopsis ,01 natural sciences ,Green fluorescent protein ,abscisic acid ,chemistry.chemical_compound ,Plant Growth Regulators ,Gene cluster ,Biology (General) ,Abscisic acid ,Spectroscopy ,Plant Proteins ,biology ,Chemistry ,Hydrolysis ,beta-Glucosidase ,food and beverages ,Esters ,General Medicine ,Plants, Genetically Modified ,phytohormone conjugates ,Apoplast ,Droughts ,Computer Science Applications ,Biochemistry ,Multigene Family ,Glucosidases ,glycosylation ,QH301-705.5 ,Transgene ,Oryza sativa ,Article ,Catalysis ,Inorganic Chemistry ,03 medical and health sciences ,Tobacco ,Extracellular ,Physical and Theoretical Chemistry ,QD1-999 ,Molecular Biology ,Organic Chemistry ,fungi ,Oryza ,biology.organism_classification ,Gibberellins ,β-Glucosidase ,Glucose ,030104 developmental biology ,biology.protein ,010606 plant biology & botany - Abstract
Conjugation of phytohormones with glucose is a means of modulating their activities, which can be rapidly reversed by the action of β-glucosidases. Evaluation of previously characterized recombinant rice β-glucosidases found that nearly all could hydrolyze abscisic acid glucose ester (ABA-GE). Os4BGlu12 and Os4BGlu13, which are known to act on other phytohormones, had the highest activity. We expressed Os4BGlu12, Os4BGlu13 and other members of a highly similar rice chromosome 4 gene cluster (Os4BGlu9, Os4BGlu10 and Os4BGlu11) in transgenic Arabidopsis. Extracts of transgenic lines expressing each of the five genes had higher β-glucosidase activities on ABA-GE and gibberellin A4 glucose ester (GA4-GE). The β-glucosidase expression lines exhibited longer root and shoot lengths than control plants in response to salt and drought stress. Fusions of each of these proteins with green fluorescent protein localized near the plasma membrane and in the apoplast in tobacco leaf epithelial cells. The action of these extracellular β-glucosidases on multiple phytohormones suggests they may modulate the interactions between these phytohormones.
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- 2021
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7. Study on spatial ecology of Asian Badger(Meles leucurus) by radio telemetry and camera trapping: focusing on home-range and hibernation sett use pattern
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Dong Gul Woo, Sang Kyu Lee, and Tae Young Choi
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Hibernation ,Geography ,Meles leucurus ,biology ,Badger ,Ecology ,Home range ,biology.animal ,Telemetry ,Spatial ecology ,biology.organism_classification ,Sett - Published
- 2019
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8. The Molecular Detection of Equine Herpesviruses 2 and 5 in Genital Swabs From Clinically Normal Thoroughbred Mares in South Korea
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Sang-Kyu Lee and Inhyung Lee
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Rhadinovirus ,Genetic diversity ,Equine ,Nucleic acid sequence ,Herpesviridae Infections ,Biology ,Virology ,DNA sequencing ,law.invention ,law ,Nasal Swab ,DNA, Viral ,Republic of Korea ,Animals ,Female ,Horse Diseases ,Sex organ ,Genitalia ,Horses ,Equine herpesvirus ,Gene ,Phylogeny ,Polymerase chain reaction - Abstract
Equine herpesvirus (EHV) 2 and equine herpesvirus 5 (EHV-5) have been getting attention as potential causative pathogens of reproductive disorders in horses. Equine herpesviruses 2 and 5 are widespread among horses and have been detected in various samples including nasal swabs, blood, and ocular swabs. However, the detection of these pathogens in genital swabs has not been determined. The aims of this study were to determine the positive rate of EHV-2 and EHV-5 DNA in genital swabs taken from clinically normal mares and to define the genetic diversity of these EHV-2 and EHV-5 DNA sequences by comparing them to previously reported EHV-2 and EHV-5 nucleotide sequences. Four hundred and thirty genital swabs from clinically normal mares were tested for EHV-2 and EHV-5 by glycoprotein B (gB)-specific polymerase chain reaction. From 430 genital swabs, 10 (2.3%) contained EHV-2 DNA, and 11 (2.6%) were positive for EHV-5. The sequences of the EHV-2 and EHV-5 gB gene were used in phylogenetic analyses and revealed that the Korean EHV-2 and EHV-5 strains have a marked genetic diversity, with a nucleotide sequence identity among the strains that ranged from 92.57% to 100% and from 98.07% to 100% for EHV-2 and EHV-5, respectively. The degree of similarity between Korean strains and those recovered from horses elsewhere ranged from 88.13% to 100% for EHV-2 and 95.96% to 100% for EHV-5. Further studies are now required to determine if the presence of EHV-2 and EHV-5 DNA is associated with reproductive disorders in clinically affected horses.
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- 2019
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9. First records of two squat lobsters (Decapoda, Galatheidae) from Korea
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Sang-Hui Lee, Sa Heung Kim, Won Kim, and Sang-kyu Lee
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Carcinology ,Fishery ,Galatheidae ,Decapoda ,Animal Science and Zoology ,Squat ,Aquatic Science ,Biology ,biology.organism_classification - Abstract
Two galatheids, Allogalathea elegans (Adams & White, 1848) and Phylladiorhynchus pusillus (Henderson, 1885), are newly reported from Korean waters in material from around Jeju Island. The two genera, Allogalathea Baba, 1969 and Phylladiorhynchus Baba, 1969 are also reported from Korea for the first time. Now, the known Korean galatheids consist of six species belonging to three genera. Illustrations and diagnostic descriptions of the two newly recorded species are given herein.
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- 2019
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10. Valerian extract alters functional brain connectivity: A randomized double‐blind placebo‐controlled trial
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Sang-Kyu Lee, Kitack Shin, Do Hoon Kim, Daeyoung Roh, Chang Hyun Lee, Jae Hoon Jung, Lee Young Kang, and Kyung Hee Yoon
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Adult ,Male ,Valerian ,Sedation ,Placebo-controlled study ,Alpha (ethology) ,Electroencephalography ,Placebo ,03 medical and health sciences ,0302 clinical medicine ,Double-Blind Method ,Stress, Physiological ,medicine ,Humans ,Hypnotics and Sedatives ,Pharmacology ,0303 health sciences ,biology ,medicine.diagnostic_test ,Plant Extracts ,business.industry ,030302 biochemistry & molecular biology ,Therapeutic effect ,Brain ,Middle Aged ,biochemical phenomena, metabolism, and nutrition ,bacterial infections and mycoses ,biology.organism_classification ,Anti-Anxiety Agents ,030220 oncology & carcinogenesis ,Anesthesia ,Anxiety ,Female ,medicine.symptom ,business - Abstract
Valerian root is the most commonly used herbal supplement for sedation and anxiolysis, but it is unknown whether it may affect functional brain connectivity. Our goal was to use electroencephalography (EEG) to investigate whether valerian root extract (VRE) affects resting-state connectivity changes and whether such changes are associated with clinical symptoms. This 4-week, double-blinded, randomized, placebo-controlled clinical trial was conducted with 64 nonclinical volunteers suffering psychological stress. The participants received VRE (100 mg) or a placebo thrice daily. We examined VRE's therapeutic effects on anxiety and stress-related psychological constructs. Functional brain connectivity changes were measured as EEG coherence in the alpha and theta frequency bands. The VRE and placebo groups both exhibited significant postintervention improvements on all clinical scales, but no significant between-group differences in these changes were noted. Compared with the placebo group, the VRE group exhibited significantly greater increases in frontal brain region alpha coherence across four electrode pairs, and these changes were significantly correlated with anxiolysis. The VRE group also exhibited significantly greater decreases in theta coherence across another four electrodes pairs. Our findings indicate that VRE alters functional brain connectivity in relation to anxiety. Further EEG studies are needed to confirm VRE's neurophysiological effects.
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- 2019
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11. WDR76 is a RAS binding protein that functions as a tumor suppressor via RAS degradation
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Young Nyun Park, Jong Chan Park, Eun Ji Ro, Kang Yell Choi, Woo Shin Kim, Do Sik Min, Woo Jeong Jeong, Sang Kyu Lee, and Soung Hoo Jeon
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0301 basic medicine ,Male ,Proteomics ,Carcinogenesis ,Chromosomal Proteins, Non-Histone ,General Physics and Astronomy ,Cell Cycle Proteins ,02 engineering and technology ,Plasma protein binding ,medicine.disease_cause ,law.invention ,Gene Knockout Techniques ,Mice ,Liver Neoplasms, Experimental ,Ubiquitin ,law ,Diethylnitrosamine ,lcsh:Science ,Mice, Knockout ,Multidisciplinary ,biology ,Chemistry ,Liver Neoplasms ,021001 nanoscience & nanotechnology ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,Liver ,0210 nano-technology ,Protein Binding ,Carcinoma, Hepatocellular ,Science ,Primary Cell Culture ,DNA-binding protein ,General Biochemistry, Genetics and Molecular Biology ,Article ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,Cell Line, Tumor ,medicine ,Animals ,Humans ,HRAS ,Binding protein ,Tumor Suppressor Proteins ,HEK 293 cells ,Ubiquitination ,General Chemistry ,Fibroblasts ,Mice, Inbred C57BL ,030104 developmental biology ,HEK293 Cells ,Proteolysis ,Cancer research ,biology.protein ,ras Proteins ,Suppressor ,lcsh:Q ,Carrier Proteins - Abstract
Stability regulation of RAS that can affect its activity, in addition to the oncogenic mutations, occurs in human cancer. However, the mechanisms for stability regulation of RAS involved in their activity and its roles in tumorigenesis are poorly explored. Here, we identify WD40-repeat protein 76 (WDR76) as one of the HRAS binding proteins using proteomic analyses of hepatocellular carcinomas (HCC) tissue. WDR76 plays a role as an E3 linker protein and mediates the polyubiquitination-dependent degradation of RAS. WDR76-mediated RAS destabilization results in the inhibition of proliferation, transformation, and invasion of liver cancer cells. WDR76−/− mice are more susceptible to diethylnitrosamine-induced liver carcinogenesis. Liver-specific WDR76 induction destabilizes Ras and markedly reduces tumorigenesis in HRasG12V mouse livers. The clinical relevance of RAS regulation by WDR76 is indicated by the inverse correlation of their expressions in HCC tissues. Our study demonstrates that WDR76 functions as a tumor suppressor via RAS degradation., Overexpression of RAS proteins is frequently observed in patients with hepatocellular carcinoma. Here, the authors identify an HRAS binding protein, the E3 ubiquitin ligase WDR76, which promotes HRAS degradation, thus functioning as a tumour suppressor in liver cancer
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- 2019
12. A New Species of Xouthous Thomson (Copepoda: Harpacticoida: Pseudotachidiidae), Widely Distributed in the Korean Waters
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Sung Joon Song, Jung-Suk Lee, Jong Seong Khim, and Sang-kyu Lee
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0106 biological sciences ,geography ,geography.geographical_feature_category ,biology ,Meiobenthos ,010607 zoology ,Biodiversity ,Zoology ,Seta ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Sensu ,Genus ,Peninsula ,Taxonomy (biology) ,Harpacticoida ,Ecology, Evolution, Behavior and Systematics - Abstract
A new species of the genus Xouthous Thomson, 1883, previously known as Idomene, obtained from the 1995–2015 collections, from the coasts of the Korean Peninsula, is described and illustrated. To date 16 valid species of the genus including X. yeonghoonisp. nov. presented herein, have been reported from the Antarctic, Atlantic, Indian, and Pacific oceans. The new species can be easily distinguished from its congeners by the combination of the following characters: 7-segmented female antennule; antenna with 2 exopodal segments; mandibular exopod with 2 lateral strong spines and 4 distal plumose setae; exp-3 of P2–P4 with 2 strong pectinate spines; and P5 baseoendopod with truncate margin, and spatulate and parallel-sided setae. In addition to the description of the new species from Korea, comparisons to 5 closely related congeners (“palisade group”) from the Indian Ocean are also included. Finally, a mini-review on the global distribution of the genus, with a taxonomic revisit to X. laticaudatus sensu Kim (2014), is provided. The new species described herein is the first record of Xouthous from East Asia.
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- 2020
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13. Deficiency of rice hexokinase HXK5 impairs synthesis and utilization of starch in pollen grains and causes male sterility
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Jung-Il Cho, Emmanuel Guiderdoni, Jeong Eun Park, Ki-Hong Jung, Hye Rang Park, Cong Danh Nguyen, Sunok Moon, Jin Hoe Huh, Jong-Seong Jeon, Sang-Kyu Lee, Hyun-Bi Kim, Kyung Hee University (KHU), Seoul National University [Seoul] (SNU), Amélioration génétique et adaptation des plantes méditerranéennes et tropicales (UMR AGAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Département Systèmes Biologiques (Cirad-BIOS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Next Generation BioGreen 21 Program of the Rural Development Administration of Korea (PJ013172012019), and Mid-Career Researcher Program of the National Research Foundation of Korea (NRF-2017R1A2B4009687)
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0106 biological sciences ,Infertilité mâle ,the mutant pollen was unable to compete successfully against wild-type pollen. Expression of the catalytically inactive OsHXK5-G113D did not rescue the hxk5 male-sterile phenotype ,Physiology ,Starch ,Stamen ,Plant Science ,medicine.disease_cause ,01 natural sciences ,chemistry.chemical_compound ,Hexokinase ,produced via anther culture ,and additional homozygous hxk5-2 ,Tube du pollen ,Pollen maturation ,Plant Proteins ,0303 health sciences ,F63 - Physiologie végétale - Reproduction ,food and beverages ,Cell biology ,Germination ,Pollen ,Pollen tube ,Amidon ,Sterility ,There is little known about the function of rice hexokinases (HXKs) in planta. We characterized hxk5-1 ,F60 - Physiologie et biochimie végétale ,Oryza sativa ,Biology ,rather than its role in sugar sensing and signaling. Our results demonstrate that OsHXK5 contributes to a large portion of the hexokinase activity necessary for the starch utilization pathway during pollen germination and tube growth ,Germination du pollen ,03 medical and health sciences ,a Tos17 mutant of OsHXK5 that is up-regulated in maturing pollen ,medicine ,otorhinolaryngologic diseases ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,indicating that its catalytic function was responsible for pollen fertility ,although they were sufficient to produce some viable seed. However ,030304 developmental biology ,a stage when starch accumulates. Progeny analysis of self-pollinated heterozygotes of hxk5-1 and reciprocal crosses between the wild-type and heterozygotes revealed that loss of HXK5 causes male sterility. Homozygous hxk5-1 ,Base Sequence ,hxk5-3 and hxk5-4 lines created by CRISPR/Cas9 confirmed the male-sterile phenotype. In vitro pollen germination ability and in vivo pollen tube growth rate were significantly reduced in the hxk5 mutant pollen. Biochemical analysis of anthers with the mutant pollen revealed significantly reduced hexokinase activity and starch content ,Oryza ,Fertility ,chemistry ,as well as for starch biosynthesis during pollen maturation ,010606 plant biology & botany - Abstract
International audience; There is little known about the function of rice hexokinases (HXKs) in planta. We characterized hxk5-1, a Tos17 mutant of OsHXK5 that is up-regulated in maturing pollen, a stage when starch accumulates. Progeny analysis of self-pollinated heterozygotes of hxk5-1 and reciprocal crosses between the wild-type and heterozygotes revealed that loss of HXK5 causes male sterility. Homozygous hxk5-1, produced via anther culture, and additional homozygous hxk5-2, hxk5-3 and hxk5-4 lines created by CRISPR/Cas9 confirmed the male-sterile phenotype. In vitro pollen germination ability and in vivo pollen tube growth rate were significantly reduced in the hxk5 mutant pollen. Biochemical analysis of anthers with the mutant pollen revealed significantly reduced hexokinase activity and starch content, although they were sufficient to produce some viable seed. However, the mutant pollen was unable to compete successfully against wild-type pollen. Expression of the catalytically inactive OsHXK5-G113D did not rescue the hxk5 male-sterile phenotype, indicating that its catalytic function was responsible for pollen fertility, rather than its role in sugar sensing and signaling. Our results demonstrate that OsHXK5 contributes to a large portion of the hexokinase activity necessary for the starch utilization pathway during pollen germination and tube growth, as well as for starch biosynthesis during pollen maturation.
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- 2020
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14. Gene Expression Analysis and Polymorphism Discovery to Investigate Drought Responsive System in Tropical Maize
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Kitae Song, Sang-Kyu Lee, Byung-Moo Lee, Jun-Cheol Moon, Kyung-Hee Kim, Jae Yoon Kim, and Hyo Chul Kim
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0106 biological sciences ,0301 basic medicine ,Gene expression profiling ,Genetics ,03 medical and health sciences ,030104 developmental biology ,Polymorphism (computer science) ,Gene expression ,Plant Science ,Biology ,01 natural sciences ,010606 plant biology & botany ,Biotechnology - Published
- 2018
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15. A small molecule approach to degrade RAS with EGFR repression is a potential therapy for KRAS mutation-driven colorectal cancer resistance to cetuximab
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Sang Kyu Lee, Tae Il Kim, Hyuntae Kim, Do Sik Min, Woo Jeong Jeong, Pu Hyeon Cha, Yong Hee Cho, Eun Ji Ro, Gyoonhee Han, Jeong Soo Yoon, Kang Yell Choi, and Ji Eun Park
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0301 basic medicine ,Colorectal cancer ,Adenomatous polyposis coli ,Clinical Biochemistry ,lcsh:Medicine ,Cetuximab ,Antineoplastic Agents ,medicine.disease_cause ,Biochemistry ,Article ,lcsh:Biochemistry ,Proto-Oncogene Proteins p21(ras) ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Panitumumab ,lcsh:QD415-436 ,Epidermal growth factor receptor ,Wnt Signaling Pathway ,neoplasms ,Molecular Biology ,beta Catenin ,Glycogen Synthase Kinase 3 beta ,biology ,business.industry ,lcsh:R ,Cancer ,medicine.disease ,digestive system diseases ,ErbB Receptors ,Mice, Inbred C57BL ,030104 developmental biology ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,Mutation ,Proteolysis ,Cancer research ,biology.protein ,Molecular Medicine ,KRAS ,Colorectal Neoplasms ,business ,Carcinogenesis ,medicine.drug - Abstract
Drugs targeting the epidermal growth factor receptor (EGFR), such as cetuximab and panitumumab, have been prescribed for metastatic colorectal cancer (CRC), but patients harboring KRAS mutations are insensitive to them and do not have an alternative drug to overcome the problem. The levels of β-catenin, EGFR, and RAS, especially mutant KRAS, are increased in CRC patient tissues due to mutations of adenomatous polyposis coli (APC), which occur in 90% of human CRCs. The increases in these proteins by APC loss synergistically promote tumorigenesis. Therefore, we tested KYA1797K, a recently identified small molecule that degrades both β-catenin and Ras via GSK3β activation, and its capability to suppress the cetuximab resistance of KRAS-mutated CRC cells. KYA1797K suppressed the growth of tumor xenografts induced by CRC cells as well as tumor organoids derived from CRC patients having both APC and KRAS mutations. Lowering the levels of both β-catenin and RAS as well as EGFR via targeting the Wnt/β-catenin pathway is a therapeutic strategy for controlling CRC and other types of cancer with aberrantly activated the Wnt/β-catenin and EGFR-RAS pathways, including those with resistance to EGFR-targeting drugs attributed to KRAS mutations., Colorectal cancer: Potential treatment for drug-resistant cases A recently identified small molecule shows promise for tackling resistance to a leading colorectal cancer drug. Three proteins that are over-expressed in colorectal cancer are epidermal growth factor receptor (EGFR), RAS and β-catenin. These proteins and their interconnected signaling pathways are therefore important therapeutic targets. EGFR is the target of the drug cetuximab, but many patients are resistant to this drug attributed to mutations in a gene that influences the signaling pathways of the three key proteins. Kang-Yell Choi at Yonsei University in Seoul, South Korea, and co-workers trialed a novel molecular drug on human colorectal cancer tissues and on mice. They confirmed that the new drug leads to reduced EGFR levels by degrading RAS and β-catenin and therefore suppresses the growth of colorectal cancer cells in samples with or without the resistant mutations.
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- 2018
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16. Status of Taylorella equigenitalis Infection in Thoroughbred Horses in the Republic of Korea and the Molecular Characterization of the Korean Taylorella equigenitalis Isolates
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Hyun-Jeong Kim, Hyoung-Seok Yang, Hae-Eun Kang, Soo-Kyoung Lee, Sung-Hee Kim, Changnam Park, Jun-Gu Choi, Sun-Joo Yang, Sang Kyu Lee, Jin A Ko, Hye-Young Jeoung, and Jee-Yong Park
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0301 basic medicine ,medicine.medical_specialty ,education.field_of_study ,Veterinary medicine ,040301 veterinary sciences ,Equine ,Population ,Outbreak ,04 agricultural and veterinary sciences ,Biology ,biology.organism_classification ,law.invention ,0403 veterinary science ,03 medical and health sciences ,030104 developmental biology ,law ,Quarantine ,Taylorella equigenitalis ,Epidemiology ,medicine ,Multilocus sequence typing ,education ,Contagious equine metritis ,Polymerase chain reaction - Abstract
Contagious equine metritis is a highly transmissible venereal disease of horses caused by the bacterium, Taylorella equigenitalis. After the first identification of T. equigenitalis in Korea in 2015, targeted surveillance of Thoroughbreds was conducted using real-time polymerase chain reaction. Initially, the prevalence of T. equigenitalis in the Thoroughbred population tested was 13.5% (71/526). All positive animals were placed under quarantine and treated according to previously described protocols (Jeoung et al., J Equine Vet Sci, 2016; 47:42–6). After the initial outbreak identification, annual national surveillance for T. equigenitalis was conducted from 2015 to 2017, and by 2017, prevalence was reduced to 1.0% (22/2,171). Most positive cases were located in Jeju province, the major horse-rearing region in Korea. A total of 12 T. equigenitalis strains were isolated during the surveillance period, and multilocus sequence typing (MLST) and eBURST analysis were applied to determine epidemiological characteristics. All Korean strains showed a unique MLST allelic profile (1-2-1-2-2-2-1; gltA-gyrB-fh-shmt-tyrB-adk in order) and were classified as sequence type 55. In addition, they showed little relationship with T. equigenitalis strains isolated from other countries. Considering the unique biological and genetic characteristics of the Korean isolates, effective quarantine measures and continued surveillance will be required to eradicate the disease and prevent incursions of additional T. equigenitalis strains into Korea.
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- 2018
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17. Interaction of the Wnt/β-catenin and RAS-ERK pathways involving co-stabilization of both β-catenin and RAS plays important roles in the colorectal tumorigenesis
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Kang Yell Choi, Jeong Ha Hwang, and Sang Kyu Lee
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0301 basic medicine ,MAPK/ERK pathway ,Cancer Research ,Colorectal cancer ,Adenomatous polyposis coli ,Biology ,medicine.disease_cause ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,Cancer stem cell ,Genetics ,medicine ,Animals ,Humans ,Wnt Signaling Pathway ,Molecular Biology ,beta Catenin ,Wnt signaling pathway ,medicine.disease ,Gene Expression Regulation, Neoplastic ,Cell Transformation, Neoplastic ,030104 developmental biology ,Catenin ,Cancer research ,biology.protein ,Molecular Medicine ,KRAS ,Colorectal Neoplasms ,Carcinogenesis - Abstract
Cancer development is usually driven by multiple genetic and molecular alterations rather than by a single defect. In the human colorectal cancer (CRC), series of mutations of genes are involved in the different stages of tumorigenesis. For example, adenomatous polyposis coli (APC) and KRAS mutations have been known to play roles in the initiation and progression of the tumorigenesis, respectively. However, many studies indicate that mutations of these two genes, which play roles in the Wnt/β-catenin and RAS-extra-cellular signal regulated kinase (ERK) pathways, respectively, cooperatively interact in the tumorigenesis in several different cancer types including CRC. Both Apc and Kras mutations critically increase number and growth rate of tumors although single mutation of these genes does not significantly enhance the small intestinal tumorigenesis of mice. Both APC and KRAS mutations even result in the liver metastasis with inductions of the cancer stem cells (CSCs) markers in a mice xenograft model. In this review, we are going to describe the history for interaction between the Wnt/β-catenin and RAS/ERK pathways especially related with CRC, and provide the mechanical basis for the cross-talk between the two pathways. The highlight of the crosstalk involving the stability regulation of RAS protein via the Wnt/β-catenin signaling which is directly related with the cellular proliferation and transformation will be discussed. Activation status of GSK3β, a key enzyme involving both β-catenin and RAS degradations, is regulated by the status of the Wnt/β-catenin signaling dependent upon extracellular stimuli or intracellular abnormalities of the signaling components. The levels of both β-catenin and RAS proteins are co-regulated by the Wnt/β-catenin signaling, and these proteins are overexpressed with a positive correlation in the tumor tissues of CRC patients. These results indicate that the elevation of both β-catenin and RAS proteins is pathologically significant in CRC. In this review, we also will discuss further involvement of the increments of both β-catenin and RAS especially mutant KRAS in the activation of CSCs and metastasis. Overall, the increments of β-catenin and RAS especially mutant KRAS by APC loss play important roles in the cooperative tumorigenesis of CRC.
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- 2018
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18. Engineering rice with lower grain arsenic
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Jong-Seong Jeon, Jian Feng Ma, Sang Kyu Lee, Youngsook Lee, Won Yong Song, Fenglin Deng, Naoki Yamaji, and Enrico Martinoia
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0106 biological sciences ,0301 basic medicine ,Saccharomyces cerevisiae Proteins ,Glutamate-Cysteine Ligase ,Chromosomal translocation ,Plant Science ,Biology ,01 natural sciences ,03 medical and health sciences ,Food chain ,Promoter Regions, Genetic ,Research Articles ,vacuolar sequestration ,Oryza sativa ,rice ,arsenic ,food and beverages ,Staple food ,Oryza ,Plants, Genetically Modified ,Genetically modified rice ,030104 developmental biology ,Agronomy ,Genes, Bacterial ,Toxicity ,Brown rice ,ATP-Binding Cassette Transporters ,Phloem ,ABC transporter ,Edible Grain ,Genetic Engineering ,Agronomy and Crop Science ,010606 plant biology & botany ,Biotechnology ,Research Article - Abstract
Summary Arsenic (As) is a poisonous element that causes severe skin lesions and cancer in humans. Rice (Oryza sativa L.) is a major dietary source of As in humans who consume this cereal as a staple food. We hypothesized that increasing As vacuolar sequestration would inhibit its translocation into the grain and reduce the amount of As entering the food chain. We developed transgenic rice plants expressing two different vacuolar As sequestration genes, ScYCF1 and OsABCC1, under the control of the RCc3 promoter in the root cortical and internode phloem cells, along with a bacterial γ‐glutamylcysteine synthetase driven by the maize UBI promoter. The transgenic rice plants exhibited reduced root‐to‐shoot and internode‐to‐grain As translocation, resulting in a 70% reduction in As accumulation in the brown rice without jeopardizing agronomic traits. This technology could be used to reduce As intake, particularly in populations of South East Asia suffering from As toxicity and thereby improve human health.
- Published
- 2018
19. Application of ZFN for Site Directed Mutagenesis of Rice SSIVa Gene
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Yu Jin Jung, Sang-Kyu Lee, Kwon-Kyoo Kang, Yong-Gu Cho, and Franz Marielle Nogoy
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0106 biological sciences ,0301 basic medicine ,Genetics ,Gene isoform ,Zinc finger ,biology ,fungi ,Biomedical Engineering ,food and beverages ,Bioengineering ,Locus (genetics) ,01 natural sciences ,Applied Microbiology and Biotechnology ,Zinc finger nuclease ,03 medical and health sciences ,030104 developmental biology ,Genome editing ,biology.protein ,Site-directed mutagenesis ,Starch synthase ,Gene ,010606 plant biology & botany ,Biotechnology - Abstract
Many successful studies on genome editing in plants have been reported and one of the popular genome editing technology used in plants is Zinc Finger Nucleases (ZFN), which are chimeric proteins composed of synthetic zinc finger-based DNA binding domain and a DNA cleavage domain. The objective of this research was to utilize ZFNs to induce a double-stranded break in SSIVa, a soluble starch synthase involved in starch biosynthesis pathway, leading to the regulation of the SSIVa expression. The isoform SSIVa is not yet well studied, thus, by modifying the endogenous loci in SSIVa, we can explore on the specific roles of this gene in starch biosynthesis and other possible functions it might play. In this study, we used ZFN-mediated targeted gene disruption in the coding sequence of the SSIVa rice gene in an effort to elucidate the functional role of the gene. Generation of transgenic plants carrying premature stop codons and substitution events, revealed no SSIVa mRNA expression, low starch contents and dwarf phenotypes. Remarkably, based on our analysis SSIVa gene disruption had no effect on other starch synthesis related genes as their expression remained at wild type levels. Therefore, the engineered ZFNs can efficiently cleave and stimulate mutations at SSIVa locus in rice to
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- 2018
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20. First comprehensive ecological checklist of Brachyura in Korea: 1879–2020
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Sung Joon Song, Jong Seong Khim, Changkeun Lee, Junsung Noh, and Sang-kyu Lee
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geography.geographical_feature_category ,biology ,Brachyura ,Ecology ,Hemigrapsus sanguineus ,Baseline (sea) ,Biodiversity ,Aquatic Science ,Oceanography ,biology.organism_classification ,Pollution ,Checklist ,Biodiversity hotspot ,Geography ,Habitat ,Republic of Korea ,Archipelago ,Animals ,Cosmopolitan distribution ,Ecosystem - Abstract
The increasing concerns and management needs on marine biodiversity have escalated the requirement for timely documentation of the marine taxa. We first established a comprehensive ecological checklist of Korean Brachyura through a meta-analysis of 74 documents (since the 1870s). A total of 247 species inhabiting the Korean coastal waters are listed with some key ecological information; habitat, substrate, distribution, and delta +. The crabs predominated on Jejudo Island, at the southernmost point of Korea, followed by the South Sea, West Sea, and East Sea. Portunus trituberculatus and Hemigrapsus sanguineus were cosmopolitan species widely distributed across the three seas. Dynamic oceanographic settings of the South Sea, such as archipelago, Rias coast, varied habitats, and (in)direct influence of Kuroshio warm current, seemed to support high crab diversity. The rocky and subtidal habitats represented biodiversity hotspots. The present study would be a useful baseline for gathering further ecological information of globally important marine taxa in Korea and elsewhere.
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- 2021
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21. Development and Application of a Multiplex Real-Time Polymerase Chain Reaction Assay for the Simultaneous Detection of Bacterial Aetiologic Agents Associated With Equine Venereal Diseases
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Sun-Joo Yang, Jong-Soo Lee, Hyun Jeong Kim, Jun-Gu Choi, Taemok Park, Soo-Koung Lee, Hae-Eun Kang, Hye-Young Jeoung, Jee-Yong Park, Sung Hee Kim, Ji-Hye Lee, Sang Kyu Lee, and YongJoo Kim
- Subjects
Equine ,Klebsiella pneumoniae ,Biology ,Real-Time Polymerase Chain Reaction ,medicine.disease ,biology.organism_classification ,law.invention ,Microbiology ,law ,Taylorella equigenitalis ,Streptococcus zooepidemicus ,medicine ,Taylorella asinigenitalis ,Animals ,Taylorella ,Multiplex ,Horses ,Klebsiella pneumonia ,Gram-Negative Bacterial Infections ,Contagious equine metritis ,Polymerase chain reaction - Abstract
Venereal diseases caused by bacteria are important to the equine industry due to economic losses caused by decline of conception rate in breeding horses. Therefore, identification of infected animals as well as the implementation of appropriate managerial procedures based on accurate diagnosis is critical. In this study, two types of multiplex real-time polymerase chain reaction with high sensitivity and specificity were developed for the simultaneous detection and differentiation of five commonly associated bacterial pathogens of venereal diseases in horses, consisting of Taylorella equigenitalis, Taylorella asinigenitalis, Pseudomonas aeruginosa, Klebsiella pneumoniae and Streptococcus zooepidemicus. The assay was applied to samples collected as part of the surveillance of T.equigenitalis infection in South Korea. Swab samples collected from horses in 2015 were tested. T. equigenitalis and K. pneumoniae was detected in 21 (21.0%) and two (2.0%) samples, respectively. No samples were positive for T. asinigenitalis, P. aeruginosa, and S. zooepidemicus. Application of this assay to an existing surveillance program has allowed for an enhanced surveillance for a wider range of venereal diseases of equine to be implemented in South Korea.
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- 2021
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22. Stabilization of Sur8 via PKCα/δ degradation promotes transformation and migration of colorectal cancer cells
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Pu Hyeon Cha, Do Sik Min, Woo Jeong Jeong, Kang Yell Choi, Kug Hwa Lee, and Sang Kyu Lee
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0301 basic medicine ,MAPK/ERK pathway ,Scaffold protein ,Cell signaling ,biology ,Chemistry ,Regulator ,Sur8 ,colorectal cancer ,protein kinase C α/δ ,Fibroblast growth factor ,Cell biology ,03 medical and health sciences ,fibroblast growth factor-2 ,030104 developmental biology ,0302 clinical medicine ,Oncology ,030220 oncology & carcinogenesis ,Mitogen-activated protein kinase ,biology.protein ,Phosphorylation ,Protein kinase A ,Research Paper ,Ras signaling - Abstract
Scaffold proteins of the mitogen activated protein kinase (MAPK) pathway recruit protein kinase cascades to confer context-specificity to cellular signaling. Varying concentrations of scaffold proteins determine different aspects of signaling outputs. However, regulatory mechanisms of scaffold proteins are poorly understood. Sur8, a scaffold protein in the Ras-MAPK pathway, is known to be involved in cell transformation and migration, and is increased in human colorectal cancer (CRC) patient tissue. Here we determine that regulation of Sur8 stability mediates transformation and migration of CRC cells. Fibroblast growth factor 2 (FGF2) is identified as an external regulator that stabilizes Sur8. Protein kinase C-alpha and -delta (PKCα/δ) are also identified as specific mediators of FGF2 regulation of Sur8 stability. PKCα/δ phosphorylate Sur8 at Thr-71 and Ser-297, respectively. This phosphorylation is essential for polyubiquitin-dependent degradation of Sur8. Sur8 mutations, which mimic phosphorylation by PKCα/δ and destabilized Sur8, suppress the FGF2-induced transformation and migration of CRC cells. The clinical relevance of Sur8 regulation by PKCα/δ is indicated by the inverse relationship between PKCα/δ and Sur8 expression in human CRC patient tissues. Overall, our findings demonstrate for the first time a regulatory mechanism of Sur8 stability involving cellular transformation and migration in CRC.
- Published
- 2017
23. LIKE SEX4 1 Acts as a β-Amylase-Binding Scaffold on Starch Granules during Starch Degradation
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Alexander Graf, Oliver Kötting, Wei-Ling Lue, Martin Umhang, Dylan M. Silver, Samuel C. Zeeman, Steven P. Briggs, Jychian Chen, Simona Eicke, Tina B. Schreier, Sylvain Bischof, Sang Kyu Lee, Zhouxin Shen, Greg B. G. Moorhead, Martha Stadler-Waibel, Antonia Müller, and David Seung
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0106 biological sciences ,0301 basic medicine ,Starch ,Phosphatase ,Arabidopsis ,beta-Amylase ,Plant Science ,Protein Serine-Threonine Kinases ,01 natural sciences ,Dephosphorylation ,03 medical and health sciences ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,Dual-specificity phosphatase ,Tobacco ,Protein Interaction Domains and Motifs ,Amylase ,Cloning, Molecular ,Phosphorylation ,Glucans ,Research Articles ,Glucan ,chemistry.chemical_classification ,biology ,Arabidopsis Proteins ,food and beverages ,Cell Biology ,Maltose ,Plants, Genetically Modified ,Recombinant Proteins ,Plant Leaves ,030104 developmental biology ,chemistry ,Biochemistry ,biology.protein ,Carbohydrate Metabolism ,Dual-Specificity Phosphatases ,Carbohydrate-binding module ,Carrier Proteins ,Sequence Alignment ,010606 plant biology & botany - Abstract
In Arabidopsis (Arabidopsis thaliana) leaves, starch is synthesized during the day and degraded at night to fuel growth and metabolism. Starch is degraded primarily by β-amylases, liberating maltose, but this activity is preceded by glucan phosphorylation and is accompanied by dephosphorylation. A glucan phosphatase family member, LIKE SEX4 1 (LSF1), binds starch and is required for normal starch degradation, but its exact role is unclear. Here, we show that LSF1 does not dephosphorylate glucans. The recombinant dual specificity phosphatase (DSP) domain of LSF1 had no detectable phosphatase activity. Furthermore, a variant of LSF1 mutated in the catalytic cysteine of the DSP domain complemented the starch-excess phenotype of the lsf1 mutant. By contrast, a variant of LSF1 with mutations in the carbohydrate binding module did not complement lsf1. Thus, glucan binding, but not phosphatase activity, is required for the function of LSF1 in starch degradation. LSF1 interacts with the β-amylases BAM1 and BAM3, and the BAM1-LSF1 complex shows amylolytic but not glucan phosphatase activity. Nighttime maltose levels are reduced in lsf1, and genetic analysis indicated that the starch-excess phenotype of lsf1 is dependent on bam1 and bam3. We propose that LSF1 binds β-amylases at the starch granule surface, thereby promoting starch degradation.
- Published
- 2019
24. Sex difference in IgE sensitization associated with alcohol consumption in the general population
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Daeyoung Roh, Dong-Hee Lee, Sung Won Kim, Ji-Hyeon Shin, Jin Hee Cho, Byung Guk Kim, Soo Whan Kim, and Sang-Kyu Lee
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Disease prevention ,Alcohol Drinking ,National Health and Nutrition Examination Survey ,Epidemiology ,Cross-sectional study ,Population ,lcsh:Medicine ,Immunoglobulin E ,Article ,Young Adult ,03 medical and health sciences ,Sex Factors ,0302 clinical medicine ,Internal medicine ,Hypersensitivity ,medicine ,Humans ,Young adult ,lcsh:Science ,education ,Sensitization ,Aged ,education.field_of_study ,Multidisciplinary ,biology ,business.industry ,lcsh:R ,gamma-Glutamyltransferase ,Odds ratio ,Middle Aged ,Confidence interval ,Cross-Sectional Studies ,030104 developmental biology ,medicine.anatomical_structure ,Socioeconomic Factors ,Risk factors ,biology.protein ,lcsh:Q ,Female ,Self Report ,business ,Alcohol-Related Disorders ,030217 neurology & neurosurgery - Abstract
The association of alcohol consumption and immunoglobulin E (IgE) sensitization is debated. Few population-based studies have investigated whether such associations differ by sex. We explored the association of alcohol consumption with IgE sensitization in the general population, stratified by sex. We analyzed data for 1,723 adults from the 2010 Korean National Health and Nutrition Examination Survey. We divided subjects into three groups according to their self-reported alcohol consumption or serum level of gamma-glutamyltransferase (GGT), an objective marker of alcohol consumption. After adjustments, the odds ratios (ORs) of male high-risk drinkers were 2.09 (95% confidence interval [CI], 1.34–3.28) for total IgE and 1.71 (95% CI, 1.03–2.83) for Dermatophagoides farinae (DF)-specific IgE compared with male low-risk drinkers. In females, the dog-specific IgE level was associated with high-risk drinking (OR, 11.74; 95% CI, 2.04–67.24). The ORs of males in the high-serum-GGT group were 2.73 (95% CI, 1.72–4.33) for total IgE and 2.17 (95% CI, 1.35–3.47) for DF-specific IgE compared with those in the low-serum-GGT group. This study suggests a possible link between alcohol consumption and IgE sensitization, moreover, the risk of IgE sensitization was significantly higher in male high-risk drinkers. Therefore, clinicians should consider the risk of IgE sensitization possibly afflicting male high-risk drinkers.
- Published
- 2019
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25. Loss of Function of Rice Plastidic Glycolate/Glycerate Translocator 1 Impairs Photorespiration and Plant Growth
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Jong-Seong Jeon, Guangxi Wu, Sooyeon Ko, Dae-Woo Lee, Andreas P.M. Weber, Dominik Brilhaus, Choon-Hwan Lee, Sang-Kyu Lee, and Su-Hyeon Shim
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0106 biological sciences ,0301 basic medicine ,photorespiration ,Plant Science ,lcsh:Plant culture ,Photosynthesis ,Photosystem I ,01 natural sciences ,OsPLGG1 ,03 medical and health sciences ,Arabidopsis ,lcsh:SB1-1110 ,Original Research ,photosynthesis ,biology ,Chemistry ,rice ,food and beverages ,Peroxisome ,biology.organism_classification ,Transmembrane protein ,Chloroplast ,Transmembrane domain ,030104 developmental biology ,Biochemistry ,plastidic glycolate/glycerate translocator ,Photorespiration ,010606 plant biology & botany - Abstract
Ribulose-1,5-bisphosphate carboxylase/oxygenase, the key enzyme of photosynthetic carbon fixation, is able to accept both O2 and CO2 as substrates. When it fixes O2, it produces 2-phosphoglycolate, which is detoxified by photorespiration and recycled to the Calvin-Benson-Bassham cycle. To complete photorespiration, metabolite transport across three organelles, chloroplasts, peroxisomes, and mitochondria, is necessary through transmembrane transporters. In rice (Oryza sativa) little is known about photorespiratory transmembrane transporters. Here, we identified the rice plastidic glycolate/glycerate translocator 1 (OsPLGG1), a homolog of Arabidopsis PLGG1. OsPLGG1 mutant lines, osplgg1-1, osplgg1-2, and osplgg1-3, showed a growth retardation phenotype, such as pale green leaf, reduced tiller number, and reduced seed grain weight as well as reduced photosynthetic carbon reduction rate due to low activities of photosystem I and II. The plant growth retardation in osplgg1 mutants was rescued under high CO2 condition. Subcellular localization of OsPLGG1-GFP fusion protein, along with its predicted N-terminal transmembrane domain, confirmed that OsPLGG1 is a chloroplast transmembrane protein. Metabolite analysis indicated significant accumulation of photorespiratory metabolites, especially glycolate and glycerate, which have been shown to be transported by the Arabidopsis PLGG1, and changes for a number of metabolites which are not intermediates of photorespiration in the mutants. These results suggest that OsPLGG1 is the functional plastidic glycolate/glycerate transporter, which is necessary for photorespiration and growth in rice.
- Published
- 2019
26. A Ras destabilizer KYA1797K overcomes the resistance of EGFR tyrosine kinase inhibitor in KRAS-mutated non-small cell lung cancer
- Author
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Pu Hyeon Cha, Yong Hee Cho, Tae-Hyung Kim, Jaebeom Cho, Gyoonhee Han, Ho-Young Lee, Ji Eun Park, Wook Jin Shin, Jae Heon Lee, Sang Kyu Lee, Jee Sun Yang, Do Sik Min, and Kang Yell Choi
- Subjects
0301 basic medicine ,Lung Neoplasms ,Colorectal cancer ,medicine.medical_treatment ,lcsh:Medicine ,medicine.disease_cause ,Targeted therapy ,Mice ,0302 clinical medicine ,Carcinoma, Non-Small-Cell Lung ,Epidermal growth factor receptor ,lcsh:Science ,beta Catenin ,Multidisciplinary ,biology ,Protein Stability ,Wnt signaling pathway ,ErbB Receptors ,Gene Expression Regulation, Neoplastic ,Thiazolidines ,Erlotinib ,KRAS ,medicine.drug ,MAP Kinase Signaling System ,Article ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,Erlotinib Hydrochloride ,Gefitinib ,Cell Line, Tumor ,medicine ,Animals ,Humans ,neoplasms ,Protein Kinase Inhibitors ,Cell Proliferation ,business.industry ,lcsh:R ,medicine.disease ,digestive system diseases ,respiratory tract diseases ,030104 developmental biology ,HEK293 Cells ,Drug Resistance, Neoplasm ,Cancer research ,biology.protein ,ras Proteins ,lcsh:Q ,Carcinogenesis ,business ,030217 neurology & neurosurgery - Abstract
The epidermal growth factor receptor (EGFR) inhibitors such as erlotinib and gefitinib are widely used for treatment of non-small cell lung cancer (NSCLC), but they have shown limited efficacy in an unselected population of patients. The KRAS mutations, which are identified in approximately 20% of NSCLC patients, have shown to be associated with the resistance to the EGFR tyrosine kinase inhibitors (TKIs). Currently, there is no clinically available targeted therapy which can effectively inhibit NSCLC tumors harboring KRAS mutations. This study aims to show the effectiveness of KYA1797K, a small molecule which revealed anti-cancer effect in colorectal cancer by destabilizing Ras via inhibiting the Wnt/β-catenin pathway, for the treatment of KRAS-mutated NSCLC. While erlotinib fail to have anti-transforming effect in NSCLC cell lines harboring KRAS mutations, KYA1797K effectively inhibited the Ras-ERK pathway in KRAS-mutant NSCLC cell lines. As a result, KYA1797K treatment suppressed the growth and transformation of KRAS mutant NSCLC cells and also induced apoptosis. Furthermore, KYA1797K effectively inhibited Kras-driven tumorigenesis in the KrasLA2 mouse model by suppressing the Ras-ERK pathway. The destabilization of Ras via inhibition of the Wnt/β-catenin pathway is a potential therapeutic strategy for KRAS-mutated NSCLC that is resistant to EGFR TKI.
- Published
- 2019
27. Molecular and serological surveillance of equine piroplasmosis in the Republic of Korea between 2016 and 2017
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Ji-Yeon Lim, Keun-Ho Kim, Soon-Seek Yoon, Mi-Sun Yoo, Hyun-Ji Seo, Sun-Joo Yang, Subin Min, Suk-Chan Jung, Sang Kyu Lee, and Yun Sang Cho
- Subjects
Tick-borne disease ,Theileria equi ,medicine ,Biology ,medicine.disease ,Virology ,Equine piroplasmosis ,18S ribosomal RNA ,Antineoplastic Protocols ,Serology - Published
- 2021
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28. First Isolation of Taylorella equigenitalis From Thoroughbred Horses in South Korea
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Ki-Eun Lee, Ji-Hye Lee, Sun-Joo Yang, Hye-Young Jeoung, Sang Kyu Lee, Sung-Hee Kim, Byounghan Kim, Taemok Park, Yong Joo Kim, and Jee-Yong Park
- Subjects
0301 basic medicine ,Veterinary medicine ,biology ,040301 veterinary sciences ,Equine ,04 agricultural and veterinary sciences ,biology.organism_classification ,16S ribosomal RNA ,Molecular taxonomy ,0403 veterinary science ,03 medical and health sciences ,030104 developmental biology ,Streptomycin ,Taylorella equigenitalis ,medicine ,Ribosomal DNA ,Contagious equine metritis ,medicine.drug - Abstract
Contagious equine metritis (CEM) is a highly contagious venereal disease of the equid species caused by the bacterium Taylorella equigenitalis . CEM has been reported from at least 30 countries across the world but in Asia, Japan has been the only country that had previously reported CEM, which was successfully eradicated in 2010. Since then, there had been no reports of CEM in Asia, but during the course of this study to test Thoroughbred horses in South Korea for the possible presence of CEM, a total of five strains of T. equigenitalis were isolated from four stallions and one mare which had shown no clinical signs indicative of the disease. The isolated bacteria were coccoid rod-shaped, gram negative, and were positive for oxidase, catalase and phosphatase tests. Sequencing of the 16S rDNA gene and phylogenetic analysis confirmed that the five isolates were T. equigenitalis , which showed high-sequence identity (99%–100%) with other T. equigenitalis strains. All Korean isolates were sensitive to streptomycin. This study describes the first isolation and characterization of T. equigenitalis in Thoroughbred horses raised in South Korea, representing the reintroduction of CEM into Asia.
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- 2016
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29. New record of commensal scale worms, Arctonoe vittata (Grube, 1855) and Hyperhalosydna striata (Kinberg, 1856) (Polychaeta: Polynoidae) from Korean waters
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Taeseo Park, Sang-kyu Lee, and Won Kim
- Subjects
0106 biological sciences ,Scale (ratio) ,Arctonoe vittata ,Ecology ,010604 marine biology & hydrobiology ,Arctonoe ,Biology ,Polynoidae ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences - Published
- 2016
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30. Isolation of isoprene degrading bacteria from soils, development ofisoAgene probes and identification of the active isoprene-degrading soil community using DNA-stable isotope probing
- Author
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Gregg M. Whited, Dmitrii V. Vavlline, Jacob A. Latone, Andrew T. Crombie, Sang-Kyu Lee, Yuliya A. Primak, Joseph C. McAuliffe, Myriam El Khawand, Antonia Johnston, J. Colin Murrell, and Terry J. McGenity
- Subjects
0301 basic medicine ,030106 microbiology ,Stable-isotope probing ,Biogeochemistry ,Biodegradation ,Biology ,biology.organism_classification ,Microbiology ,Carbon cycle ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Botany ,Soil microbiology ,Rhodococcus ,Ecology, Evolution, Behavior and Systematics ,Isoprene ,Bacteria - Abstract
Emissions of biogenic volatile organic compounds (bVOCs), are an important element in the global carbon cycle, accounting for a significant proportion of fixed carbon. They contribute directly and indirectly to global warming and climate change and have a major effect on atmospheric chemistry. Plants emit isoprene to the atmosphere in similar quantities to emissions of methane from all sources and each accounts for approximately one third of total VOCs. Although methanotrophs, capable of growth on methane, have been intensively studied, we know little of isoprene biodegradation. Here, we report the isolation of two isoprene-degrading strains from the terrestrial environment and describe the design and testing of polymerase chain reaction (PCR) primers targeting isoA, the gene encoding the active-site component of the conserved isoprene monooxygenase, which are capable of retrieving isoA sequences from isoprene-enriched environmental samples. Stable isotope probing experiments, using biosynthesized (13) C-labelled isoprene, identified the active isoprene-degrading bacteria in soil. This study identifies novel isoprene-degrading strains using both culture-dependent and, for the first time, culture-independent methods and provides the tools and foundations for continued investigation of the biogeography and molecular ecology of isoprene-degrading bacteria.
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- 2016
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31. Genetic complementation analysis of rice sucrose transporter genes in Arabidopsis SUC2 mutant atsuc2
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Jong-Seong Jeon, Joon-Seob Eom, Cong Danh Nguyen, Sang-Kyu Lee, and Dae-Woo Lee
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0106 biological sciences ,0301 basic medicine ,Oryza sativa ,biology ,Transgene ,fungi ,Mutant ,Wild type ,food and beverages ,Plant Science ,biology.organism_classification ,01 natural sciences ,Cell biology ,Complementation ,03 medical and health sciences ,030104 developmental biology ,Arabidopsis ,Botany ,Cauliflower mosaic virus ,Phloem ,010606 plant biology & botany - Abstract
Sucrose transporters (SUTs) play a critical role on the phloem plasma membrane in loading sucrose into the phloem of source leaves for long-distance transport to sink organs. Rice has a small gene family of five SUTs, Oryza sativa SUT1 (OsSUT1) to OsSUT5. To identify rice SUTs that function as phloem loaders, we adopted a growth restoration assay of the severe growth retardation phenotype of atsuc2, a mutant of the best-characterized Arabidopsis phloem loader AtSUC2, by introducing OsSUTs. The rice SUT genes were expressed by two different promoters, the native phloem-specific promoter of AtSUC2 (pAtSUC2) and the constitutive Cauliflower Mosaic Virus 35S (pCaMV35S) promoter. Of all the transgenic atsuc2 plants, only pAtSUC2: OsSUT1 complemented the atsuc2 mutant phenotype in a comparable manner to wild type (WT), and consistent levels of soluble sugars and starch were recovered compared to those of WT. This suggests that OsSUT1 is a functional ortholog of the Arabidopsis AtSUC2 and functions as an apoplastic phloem loader. In addition, ossut1 mutants were produced via anther culture and their primary carbohydrate levels and growth phenotypes were indistinguishable from those of WT. This suggests that the rice phloem loader OsSUT1 function may not be essential for rice vegetative growth under normal conditions.
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- 2016
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32. Functional analysis of a cold-responsive rice WRKY gene, OsWRKY71
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Ju-Kon Kim, Su-Hyun Park, Manu Kumar, Cong Danh Nguyen, Dong-Hoon Jeong, Jong-Seong Jeon, Chi-Yeol Kim, Sung-Ryong Kim, Kieu Thi Xuan Vo, and Sang-Kyu Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,Microarray analysis techniques ,Transgene ,food and beverages ,RNA ,Plant Science ,Biology ,01 natural sciences ,Genetically modified rice ,Molecular biology ,WRKY protein domain ,Green fluorescent protein ,Blot ,03 medical and health sciences ,030104 developmental biology ,Gene ,010606 plant biology & botany ,Biotechnology - Abstract
Publicly available microarray data and RNA gel blot analysis identified a rice WRKY transcription factor, OsWRKY71, that is highly upregulated in response to cold stress. Experiments with OsWRKY71 promoter:GFP transgenic rice confirmed its cold-inducible expression. Transient expression of OsWRKY71-GFP in maize mesophyll protoplasts indicated that it is localized predominantly in the nucleus and to a lesser extent in the cytosol. Transcriptional activation assays revealed that OsWRKY71 suppresses luciferase reporter activity in maize protoplasts, suggesting that it functions as a transcriptional repressor in rice. To characterize the function of OsWRKY71 in rice, we generated transgenic rice plants carrying CaMV35S promoter:OsWRKY71. Upon cold (4 °C) treatment, two selected OsWRKY71 transgenic lines, OX12 and OX21, recovered much better with respect to survival rate, photosynthetic ability, fresh weight, and dry weight than the control lines. RT-PCR analysis of known cold-responsive genes found that expression of OsTGFR and WSI76 was increased in OsWRKY71 transgenic lines in response to cold stress. Our results suggest that OsWRKY71 has a positive function in cold tolerance by regulating downstream target genes.
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- 2016
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33. Review: Crucial role of inorganic pyrophosphate in integrating carbon metabolism from sucrose breakdown to starch synthesis in rice endosperm
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Jong-Seong Jeon and Sang-Kyu Lee
- Subjects
0106 biological sciences ,0301 basic medicine ,Sucrose ,Carbon metabolism ,Starch ,Mutant ,Plant Science ,Biology ,01 natural sciences ,Phosphates ,Endosperm ,03 medical and health sciences ,chemistry.chemical_compound ,Genetics ,chemistry.chemical_classification ,fungi ,digestive, oral, and skin physiology ,food and beverages ,Oryza ,General Medicine ,Carbon ,Cytosol ,Metabolic pathway ,030104 developmental biology ,Enzyme ,chemistry ,Biochemistry ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
The endosperm is a primary constituent of mature seeds in rice as well as in other cereal crops, serving as the major storage reserve of starch. Observations indicate that the central part of the endosperm is subject to hypoxic conditions, which require a switch of energy metabolism owing to limited mitochondrial respiration. Uniquely, this endosperm generates a large source of inorganic pyrophosphate (PPi) as a byproduct of the reaction of ADP glucose pyrophosphorylase in the cytosol. Recent results derived from examination of the mutants of cereal crops, especially rice, for PPi-utilizing enzymes clearly suggest an important role of PPi as an alternative energy currency for integrating carbon metabolism from sucrose breakdown to starch synthesis in the endosperm. Thus, the present review provides an outline of the interlaced PPi-dependent metabolic pathways, which are critical for starch synthesis in the endosperm in terms of energy metabolism, along with its application to enhance yield potential.
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- 2020
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34. Genotype-specific neutralizing antibody titers against Japanese encephalitis virus genotypes 1 and 3 in horses immunized with a genotype 3 vaccine
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Ha-Hyun Kim, Sang Kyu Lee, Miryeon Ji, Dong-Kun Yang, and Bang-Hun Hyun
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Genotype ,030231 tropical medicine ,Antibodies ,Virus ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Immunology and Allergy ,Horses ,030212 general & internal medicine ,Seroconversion ,Neutralizing antibody ,Pharmacology ,biology ,Public Health, Environmental and Occupational Health ,Japanese encephalitis ,medicine.disease ,Virology ,Titer ,Infectious Diseases ,Japanese ,biology.protein ,Encephalitis ,Original Article ,Blood sampling - Abstract
Purpose Japanese encephalitis is one of the most important mosquito-borne and zoonotic diseases in Asia and the Pacific region. Although the dominant Japanese encephalitis virus (JEV) genotype has shifted from G3 to G1 in Korea since 1990, a G3 strain (Anyang 300) has been used in vaccines for horses for almost 40 years. This study aimed to investigate the seroconversion rates and geometric mean titers (GMTs) of virus-neutralizing antibodies (VNAs) against JEV G1 and G3 in horses immunized with the G3 vaccine. Materials and methods Serum samples of 1,231 horses immunized with the Anyang 300 vaccine were collected in 2018. VNA titers against JEV KV1899 (G1) and Anyang 300 (G3) were measured in all serum samples using the virus neutralization test. Titers were analyzed according to blood sampling time (prior to and following annual revaccination), age, and region. Results Rates of VNA titer >10 were 45.1% and 77.8% for G1, and 49.1% and 82.9% for G3 in samples taken before and after revaccination, respectively. GMTs of genotype-specific VNAs against JEV G1 and G3 were 8.3 and 11.6 before revaccination and rose to 27.2 and 65.4 following revaccination. Overall sero-positivity did not significantly differ between genotypes, but GMTs significantly differed among genotypes and sampling times. No significant difference was found in GMTs among age groups or regions. Conclusion Genotype-specific neutralizing antibody titers against JEV G1 and G3 differed significantly in horses immunized with the G3 vaccine. Antigenic differences between genotypes could reduce the vaccine's efficacy, requiring the development of a new vaccine.
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- 2020
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35. Molecular Detection of Equus caballus Papillomavirus Type 2 in Genital Swabs From Healthy Horses in the Republic of Korea
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Inhyung Lee, Sang-Kyu Lee, and Jung Keun Lee
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Male ,Equine ,Papillomavirus Infections ,Horse ,Biology ,biology.organism_classification ,Equus ,Virology ,Virus ,United States ,law.invention ,law ,Republic of Korea ,Genital neoplasm ,Penile Intraepithelial Neoplasia ,Animals ,Sex organ ,Female ,Horse Diseases ,Genetic variability ,Horses ,Papillomaviridae ,Polymerase chain reaction ,Phylogeny - Abstract
Equus caballus papillomavirus type 2 (EcPV-2) is implicated in genital neoplasms in horses, including equine penile papillomas, penile intraepithelial neoplasia, and squamous cell carcinoma (SCC). This virus seldom regresses spontaneously and can result in the development of SCC, which may result in significant clinical damage and economic cost. However, the prevalence of this virus is unknown in clinically unaffected horses. The aim of this study was to determine the prevalence of EcPV-2 DNA in genital swabs from healthy horses in the Republic of Korea and to investigate genetic variability within EcPV-2. A total of 797 genital swab samples obtained from Thoroughbred horses (35 stallions and 762 mares) were tested for the presence of the EcPV-2 gene E1 using a polymerase chain reaction (PCR) assay. Positive results were confirmed by repeat PCR to detect the presence of E6 and amplicon sequencing. Equus caballus papillomavirus type 2 DNA was detected in 1% (8/762) of mare swabs but in none of stallion swabs (0/35). All EcPV-2-positive mares had been imported from the United States. Equus caballus papillomavirus type 2 E6 gene sequences were used for phylogenetic analysis and revealed three subdivisions related to the European strains, and three isolates were located on two separate branches. This study documents the molecular prevalence and phylogenetic analysis of EcPV-2 DNA in the Republic of Korea.
- Published
- 2018
36. OsWRKY67 Plays a Positive Role in Basal and XA21-Mediated Resistance in Rice
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Guo-Liang Wang, Kieu Thi Xuan Vo, Sang-Kyu Lee, Sang-Won Lee, Jong-Seong Jeon, Chi-Yeol Kim, Gautam Shirsekar, Young-Su Seo, and Trung Viet Hoang
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0106 biological sciences ,0301 basic medicine ,disease resistance ,Mutant ,Xanthomonas oryzae pv. oryzae ,Plant Science ,lcsh:Plant culture ,Plant disease resistance ,01 natural sciences ,03 medical and health sciences ,Xanthomonas oryzae ,RNA interference ,lcsh:SB1-1110 ,Gene ,Original Research ,OsWRKY67 ,biology ,rice ,food and beverages ,Magnaporthe oryzae ,biology.organism_classification ,WRKY protein domain ,Elicitor ,Cell biology ,030104 developmental biology ,010606 plant biology & botany - Abstract
WRKY proteins play important roles in transcriptional reprogramming in plants in response to various stresses including pathogen attack. In this study, we functionally characterized a rice WRKY gene, OsWRKY67, whose expression is upregulated against pathogen challenges. Activation of OsWRKY67 by T-DNA tagging significantly improved the resistance against two rice pathogens, Magnaporthe oryzae and Xanthomonas oryzae pv. oryzae (Xoo). Reactive oxygen species (ROS) rapidly accumulated in OsWRKY67 activation mutant lines in response to elicitor treatment, compared with the controls. Overexpression of OsWRKY67 in rice confirmed enhanced disease resistance, but led to a restriction of plant growth in transgenic lines with high levels of OsWRKY67 protein. OsWRKY67 RNAi lines significantly reduced resistance to M. oryzae and Xoo isolates tested, and abolished XA21-mediated resistance, implying the possibility of broad-spectrum resistance from OsWRKY67. Transcriptional activity and subcellular localization assays indicated that OsWRKY67 is present in the nucleus where it functions as a transcriptional activator. Quantitative PCR revealed that the pathogenesis-related genes, PR1a, PR1b, PR4, PR10a, and PR10b, are upregulated in OsWRKY67 overexpression lines. Therefore, these results suggest that OsWRKY67 positively regulates basal and XA21-mediated resistance, and is a promising candidate for genetic improvement of disease resistance in rice.
- Published
- 2018
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37. Arabidopsis thaliana AMY3 Is a Unique Redox-regulated Chloroplastic α-Amylase
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Sang Kyu Lee, Emmanuelle Issakidis-Bourguet, Birte Svensson, Francesca Sparla, David Seung, Maher Abou Hachem, Diana Santelia, Matthias Thalmann, Samuel C. Zeeman, David Seung, Matthias Thalmann, Francesca Sparla, Maher Abou Hachem, Sang Kyu Lee, Emmanuelle Issakidis-Bourguet, Birte Svensson, Samuel C. Zeeman, Diana Santelia, and University of Zurich
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0106 biological sciences ,1303 Biochemistry ,REDOX REGULATION ,Chloroplasts ,Starch ,Arabidopsis ,Plant Biology ,580 Plants (Botany) ,01 natural sciences ,Biochemistry ,1307 Cell Biology ,Chloroplast Proteins ,03 medical and health sciences ,chemistry.chemical_compound ,10126 Department of Plant and Microbial Biology ,1312 Molecular Biology ,Amylase ,Molecular Biology ,030304 developmental biology ,Glucan ,chemistry.chemical_classification ,0303 health sciences ,biology ,Arabidopsis Proteins ,fungi ,food and beverages ,Hordeum ,Cell Biology ,Hydrogen-Ion Concentration ,biology.organism_classification ,Chloroplast ,Chloroplast stroma ,chemistry ,Amylopectin ,THIOREDOXIN ,Mutagenesis, Site-Directed ,biology.protein ,Dextrin ,alpha-Amylases ,010606 plant biology & botany - Abstract
Alfa-amylases are glucan hydrolases that cleave alfa-1,4-glucosidic bonds in starch. In vascular plants,alfa-amylases can be classified into three subfamilies. Arabidopsis has one member of each subfamily. Among them, only AtAMY3 is localized in the chloroplast. We expressed and purified AtAMY3 from Escherichia coli and carried out a biochemical characterization of the protein to find factors that regulate its activity. Recombinant AtAMY3 was active toward both insoluble starch granules and soluble substrates, with a strong preference for alfa-limit dextrin over amylopectin. Activity was shown to be dependent on a conserved aspartic acid residue (Asp666), identified as the catalytic nucleophile in other plant alfa-amylases such as the barley AMY1. AtAMY3 released small linear and branched glucans from Arabidopsis starch granules, and the proportion of branched glucans increased after the predigestion of starch with a beta-amylase. Optimal rates of starch digestion in vitro was achieved when both AtAMY3 and beta-amylase activities were present, suggesting that the two enzymes work synergistically at the granule surface. We also found that AtAMY3 has unique properties among other characterized plant -amylases, with a pH optimum of 7.5– 8, appropriate for activity in the chloroplast stroma. AtAMY3 is also redox-regulated, and the inactive oxidized form of AtAMY3 could be reactivated by reduced thioredoxins. Site-directed mutagenesis combined with mass spectrometry analysis showed that a disulfide bridge between Cys499 and Cys587 is central to this regulation. This work provides new insights into how alfa-amylase activity may be regulated in the chloroplast.
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- 2013
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38. Alanine aminotransferase 1 (OsAlaAT1) plays an essential role in the regulation of starch storage in rice endosperm
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Jong-Seong Jeon, Jungil Yang, Sang-Kyu Lee, Gynheung An, Sung-Ryul Kim, and Heebak Choi
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Alanine ,Oryza sativa ,Starch ,Amylopectin ,Mutant ,food and beverages ,Alanine Transaminase ,Oryza ,Plant Science ,General Medicine ,Biology ,Endosperm ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Gene Expression Regulation, Plant ,Amylose ,Genetics ,Agronomy and Crop Science ,Plant Proteins ,Alanine Aminotransferase 1 - Abstract
Alteration of storage substances, in particular the major storage form starch, leads to floury endosperm. Because floury mutants have physical attributes for milling processes, identification and characterization of those mutants are valuable. In this study we identified a floury endosperm mutant caused by a T-DNA insertion in Oryza sativa alanine-aminotransferase1 (OsAlaAT1). OsAlaAT1 is localized in the cytosol and has aminotransferase enzyme activity. The osalaat1 mutant has less amylose and its amylopectin is structurally altered. OsAlaAT1 is predominantly expressed in developing seeds during active starch synthesis. AlaAT catalyzes the interconversion of pyruvate to alanine, and this pathway is activated under low-oxygen conditions. Consistently, OsAlaAT1 is induced by such conditions. Expression of the starch synthesis genes AGPases, OsSSI, OsSSIIa, and OsPPDKB is decreased in the mutant. Thus, our observations suggest that OsAlaAT1 plays an essential role in starch synthesis in developing seeds that are exposed to low concentrations of oxygen.
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- 2015
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39. Proteomic analysis of the rice endosperm starch-deficient mutants osagps2 and osagpl2
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Bong-Kwan Phee, Jong-Seong Jeon, Sang-Kyu Lee, and Dae-Woo Lee
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Gel electrophoresis ,chemistry.chemical_classification ,Globulin ,Starch ,fungi ,digestive, oral, and skin physiology ,food and beverages ,Plant Science ,Biology ,Malate dehydrogenase ,Endosperm ,chemistry.chemical_compound ,chemistry ,Peptide mass fingerprinting ,Biochemistry ,biology.protein ,Storage protein ,Protein disulfide-isomerase - Abstract
ADP-glucose pyrophosphorylase (AGP) catalyzes the first committed step of starch biosynthesis in higher plants. We previously isolated two rice mutants, osagps2 and osagpl2, which have starch-deficient endosperms and lack the AGP small and large subunits, respectively. In this study, we used two-dimensional gel electrophoresis and peptide mass fingerprinting to identify differentially expressed proteins in the osagps2 and osagpl2 endosperms. We found that the osagps2 and osagpl2 endosperms exhibited reduced levels of glutelins and globulins (the major seed storage proteins), protein disulfide isomerases, and the dnaK-type endoplasmic reticulum chaperone BiP. Interestingly, the osagps2 and osagpl2 endosperms had much lower levels of malate dehydrogenase and alanine aminotransferase compared with wild type endosperm, which likely function in maintaining an adequate ATP supply for starch biosynthesis in seed endosperms that are exposed to low oxygen conditions. Furthermore, metabolomics analysis showed that the levels of free amino acids and soluble sugars were significantly increased in the osagps2 and osagpl2 endosperms. These results demonstrate that carbon and nitrogen metabolisms are tightly coordinated to ensure the proper development of rice seed endosperm.
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- 2015
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40. The identity ofCeratoplax villosaZehntner, 1894 (Crustacea: Decapoda: Pilumnidae), with description of a new species ofZehntnerianaTakeda & Ng, 2010, from Japan
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Peter K. L. Ng, Sang-Kyu Lee, and Won Kim
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biology ,Villosa ,Decapoda ,Holotype ,Pilumnidae ,Zoology ,Taxonomy (biology) ,Carapace ,Aquatic Science ,biology.organism_classification ,Crustacean - Abstract
Re-examination of the holotype male ofZehntneriana villosa(Zehntner, 1894) (from Ambon, Indonesia) shows that Japanese specimens previously referred to this species should be designated as a new species,Zehntneriana tadafumiisp. nov. The new species differs fromZ. villosain several characters, including the carapace, epistome, third maxilliped and thoracic sternum. Here, we redescribe and illustrateZ. villosas. str. and the new species. In addition, the taxonomy ofZehntnerianaNg & Takeda, 2010, is also discussed.
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- 2015
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41. Systematics of some calloporid and lacernid Cheilostomata (Bryozoa) from coastal South Korean waters, with the description of new taxa
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Dennis P. Gordon, Sang-kyu Lee, Ji Eun Seo, Andrei V. Grischenko, and Bum Sik Min
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0106 biological sciences ,Systematics ,Fauna ,Crassimarginatella ,010603 evolutionary biology ,01 natural sciences ,Bryozoa ,Lacernidae ,Peninsula ,Gymnolaemata ,Animals ,Animalia ,Calloporidae ,Ecology, Evolution, Behavior and Systematics ,Taxonomy ,Cheilostomatida ,geography ,Korea ,geography.geographical_feature_category ,biology ,Ecology ,010604 marine biology & hydrobiology ,Cheilostomata ,Biodiversity ,biology.organism_classification ,Taxon ,Animal Science and Zoology - Abstract
Six species in two families of Cheilostomata—Calloporidae and Lacernidae—are described from the southern coasts of the Korean Peninsula, resulting in a new distributional record and four new species to the Korean fauna. Further, Woosukia n. gen. is described, based on an existing species. Two species names ( Crassimarginatella crassimarginata and Arthropoma cecilii ) are deleted from the Korean faunal list owing to previous misidentification, with the net result that the Korean cheilostome fauna is increased to 125 species. The new additions to the fauna are: Crassimarginatella kumatae (Okada), Retevirgula asiana n. sp., Woosukia subhexagona (Ortmann), Arthropoma magniporosum n. sp., Arthropoma minus n. sp., and Phonicosia crena n. sp. The biogeographic relationships of some western Pacific taxa are discussed.
- Published
- 2017
42. Rice Transcription Factor OsDOF11 Modulates Sugar Transport by Promoting Expression of Sucrose Transporter and SWEET Genes
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Jinhuan Wei, Youngchul Yoo, Yunfei Wu, Suk-Yoon Kwon, Gynheung An, Sang-Kyu Lee, Sang-Won Lee, and Jong-Seong Jeon
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0106 biological sciences ,0301 basic medicine ,Sucrose ,Mutant ,Plant Science ,01 natural sciences ,Plant Roots ,03 medical and health sciences ,chemistry.chemical_compound ,Xanthomonas oryzae ,Gene Expression Regulation, Plant ,Sugar ,Molecular Biology ,Plant Proteins ,Oryza sativa ,biology ,Membrane transport protein ,food and beverages ,Membrane Transport Proteins ,Biological Transport ,Oryza ,Sucrose transport ,biology.organism_classification ,Cell biology ,Plant Leaves ,030104 developmental biology ,Phenotype ,chemistry ,biology.protein ,Phloem ,Sugars ,010606 plant biology & botany ,Transcription Factors - Abstract
Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long-distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 (OsDOF11), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdof11 mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhancement did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdof11 plants than in the WT. Expression of four Sucrose Transporter (SUT) genes-OsSUT1, OsSUT3, OsSUT4, and OsSUT5-as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEET11 and OsSWEET14, was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOF11 directly binds the promoter regions of SUT1, OsSWEET11, and OsSWEET14, indicating that the expression of these transporters responsible for sucrose transport via apoplastic loading is coordinately controlled by OsDOF11. We also observed that osdof11 mutant plants were less susceptible to infection by Xanthomonas oryzae pathovar oryzae, suggesting that OsDOF11 participates in sugar distribution during pathogenic invasion. Collectively, these results suggest that OsDOF11 modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice.
- Published
- 2017
43. Demonstration of monolignol β-glucosidase activity of rice Os4BGlu14, Os4BGlu16 and Os4BGlu18 in Arabidopsis thaliana bglu45 mutant
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Supaporn Baiya, Jong-Seong Jeon, Bancha Mahong, Sang-Kyu Lee, and James R. Ketudat Cairns
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0106 biological sciences ,0301 basic medicine ,Physiology ,Mutant ,Arabidopsis ,Plant Science ,01 natural sciences ,Syringin ,03 medical and health sciences ,chemistry.chemical_compound ,Glucoside ,Genetics ,Arabidopsis thaliana ,Plant Proteins ,Glycoside hydrolase family 1 ,biology ,fungi ,Oryza ,biology.organism_classification ,Plants, Genetically Modified ,Coniferin ,030104 developmental biology ,chemistry ,Biochemistry ,Mutation ,Monolignol ,Glucosidases ,010606 plant biology & botany - Abstract
The glycoside hydrolase family 1 members Os4BGlu14, Os4BGlu16, and Os4BGlu18 were proposed to be rice monolignol β-glucosidases. In vitro studies demonstrated that the Os4BGlu16 and Os4BGlu18 hydrolyze the monolignol glucosides coniferin and syringin with high efficiency compared to other substrates. The replacement of the conserved catalytic acid/base glutamate residue by a nonionizable glutamine residue in Os4BGlu14 suggested that it may be inactive as a β-glucosidase. Here, we investigated the activities of Os4BGlu14, Os4BGlu16, and Os4BGlu18 in planta by recombinant expression of their genes in the Arabidopsis bglu45-2 (monolignol β-glucosidase) mutant and analysis of monolignol glucosides by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MSMS). The bglu45-2 line exhibits elevated monolignol glucoside levels, but lower amounts of coniferin, syringin, and p-coumaryl alcohol glucoside were seen in Arabidopsis bglu45-2 rescued lines complemented by the Os4BGlu14, Os4BGlu16, and Os4BGlu18 genes. These data suggest that the bglu45-2 mutant has a broader effect on monolignols than previously reported and that the Os4BGlu14, Os4BGlu16 and Os4BGlu18 proteins act as monolignol β-glucosidases to complement the defect. An OsBGlu16-GFP fusion protein localized to the cell wall. This apoplastic localization and the effect of these enzymes on monolignol glucoside levels suggest monolignol glucosides from the vacuole may meet the monolignol β-glucosidases, despite their different localization.
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- 2017
44. Crosstalk between diurnal rhythm and water stress reveals an alteredprimary carbon flux into soluble sugars in drought-treated rice leaves
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Sang-Kyu Lee, Jong-Seong Jeon, Hee-Jeong Jeong, Ki-Hong Jung, Seo-Woo Kim, and Gynheung An
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0106 biological sciences ,0301 basic medicine ,Science ,Biology ,Photosynthesis ,Genes, Plant ,01 natural sciences ,Article ,Carbon Cycle ,Transcriptome ,03 medical and health sciences ,Diurnal cycle ,Gene Expression Regulation, Plant ,Stress, Physiological ,Botany ,Gene Regulatory Networks ,Chlorophyll fluorescence ,Multidisciplinary ,Oryza sativa ,Abiotic stress ,Gene Expression Profiling ,fungi ,Computational Biology ,food and beverages ,Molecular Sequence Annotation ,Oryza ,Circadian Rhythm ,Droughts ,Gene expression profiling ,Plant Leaves ,Metabolic pathway ,030104 developmental biology ,Gene Ontology ,Medicine ,Sugars ,Genome, Plant ,Metabolic Networks and Pathways ,010606 plant biology & botany ,Signal Transduction - Abstract
Plants retain rhythmic physiological responses when adapting to environmental challenges. However, possible integrations between drought conditions and those responses have not received much focus, especially regarding crop plants, and the relationship between abiotic stress and the diurnal cycle is generally not considered. Therefore, we conducted a genome-wide analysis to identify genes showing both diurnal regulation and water-deficiency response in rice (Oryza sativa). Among the 712 drought-responsive genes primary identified, 56.6% are diurnally expressed while 47.6% of the 761 that are down-regulated by drought are also diurnal. Using the β-glucuronidase reporter system and qRT-PCR analyses, we validated expression patterns of two candidate genes, thereby supporting the reliability of our transcriptome data. MapMan analysis indicated that diurnal genes up-regulated by drought are closely associated with the starch-sucrose pathway while those that are down-regulated are involved in photosynthesis. We then confirmed that starch-sucrose contents and chlorophyll fluorescence are altered in a diurnal manner under drought stress, suggesting these metabolic diurnal alterations as a novel indicator to evaluate the drought response in rice leaves. We constructed a functional gene network associated with the starch-sucrose KEGG metabolic pathway for further functional studies, and also developed a regulatory pathway model that includes OsbZIP23 transcription factor.
- Published
- 2017
45. Ginsenosides Inhibit HMGB1-induced Inflammatory Responses in HUVECs and in Murine Polymicrobial Sepsis
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Jong-Sup Bae, Tae Cheon Jeong, Wonhwa Lee, Sang Kyu Lee, and Sae-Kwang Ku
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Sepsis ,biology ,business.industry ,Vascular inflammation ,Immunology ,biology.protein ,medicine ,General Chemistry ,Polymicrobial sepsis ,HMGB1 ,medicine.disease ,business - Published
- 2014
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46. Hyperforin attenuates microglia activation and inhibits p65-Ser276 NFκB phosphorylation in the rat piriform cortex following status epilepticus
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Sang-Kyu Lee, Min-Ju Kim, Ji-Eun Kim, Yeon-Joo Kim, and Tae-Cheon Kang
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Male ,Fluorescent Antibody Technique ,Piriform Cortex ,Status epilepticus ,Phloroglucinol ,Pharmacology ,CREB ,TRPC6 ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Status Epilepticus ,Piriform cortex ,medicine ,Animals ,Phosphorylation ,Neuroinflammation ,biology ,Microglia ,Terpenes ,General Neuroscience ,Transcription Factor RelA ,Electroencephalography ,General Medicine ,Rats ,Hyperforin ,medicine.anatomical_structure ,chemistry ,biology.protein ,NMDA receptor ,medicine.symptom ,Neuroscience - Abstract
Hyperforin, a lipophilic constituent of medicinal herb St. John's Wort, has neurobiological effects including antidepressant activity, antibiotic potency, anti-inflammatory activity and anti-tumoral properties. Furthermore, hyperforin activates transient receptor potential conical channel-6 (TRPC6), a nonselective cation channel. To elucidate the roles of hyperforin and TRPC6 in neuroinflammation in vivo, we investigated the effect of hyperforin on neuroinflammatory responses and its related events in the rat piriform cortex (PC) following status epilepticus (SE). Hyperforin attenuated microglial activation, p65-serine 276 NFκB phosphorylation, and suppressed TNF-α expression in the PC following SE. Hyperforin also effectively alleviated SE-induced vasogenic edema formation, neuronal damage, microglial TRPC6 induction and blood-derived monocyte infiltration. Our findings suggest that hyperforin may effectively attenuate microglia-mediated neuroinflammation in the TRPC6-independent manner.
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- 2014
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47. OsWRKY42 Represses OsMT1d and Induces Reactive Oxygen Species and Leaf Senescence in Rice
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Muho Han, Junok Lee, Jong-Seong Jeon, Chi-Yeol Kim, and Sang-Kyu Lee
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Chlorophyll ,Senescence ,Chromatin Immunoprecipitation ,Biology ,Article ,Gene Expression Regulation, Plant ,Promoter Regions, Genetic ,Molecular Biology ,Gene ,Cells, Cultured ,Cellular Senescence ,Plant Proteins ,chemistry.chemical_classification ,Reactive oxygen species ,Oryza sativa ,fungi ,food and beverages ,Oryza ,Free Radical Scavengers ,Cell Biology ,General Medicine ,Plants, Genetically Modified ,Phenotype ,Genetically modified rice ,Molecular biology ,WRKY protein domain ,Plant Leaves ,Repressor Proteins ,chemistry ,Metallothionein ,Reactive Oxygen Species ,Chromatin immunoprecipitation ,Protein Binding - Abstract
We isolated a rice (Oryza sativa L.) WRKY gene which is highly upregulated in senescent leaves, denoted OsWRKY42. Analysis of OsWRKY42-GFP expression and its effects on transcriptional activation in maize protoplasts suggested that the OsWRKY42 protein functions as a nuclear transcriptional repressor. OsWRKY42-overexpressing (OsWR KY42OX) transgenic rice plants exhibited an early leaf senescence phenotype with accumulation of the reactive oxygen species (ROS) hydrogen peroxide and a reduced chlorophyll content. Expression analysis of ROS producing and scavenging genes revealed that the metallothionein genes clustered on chromosome 12, especially OsMT1d, were strongly repressed in OsWRKY42OX plants. An OsMT1d promoter:LUC construct was found to be repressed by OsWRKY42 overexpression in rice protoplasts. Finally, chromatin immunoprecipitation analysis demonstrated that OsWRKY42 binds to the W-box of the OsMT1d promoter. Our results thus suggest that OsWRKY42 represses OsMT1d-mediated ROS scavenging and thereby promotes leaf senescence in rice.
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- 2014
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48. Prevalence of Methicillin-resistant Staphylococci Isolates from Horses and Horse-related Personnel in Korea
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Ki-Jeong Na, Jae-Ik Han, Hyun-Gu Kang, Sang-Kyu Lee, and Ill-Hwa Kim
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Veterinary medicine ,education.field_of_study ,food.ingredient ,General Veterinary ,SCCmec ,Population ,Horse ,Biology ,medicine.disease_cause ,16S ribosomal RNA ,law.invention ,Microbiology ,food ,law ,medicine ,Agar ,Sheep blood ,education ,Staphylococcus ,Polymerase chain reaction - Abstract
Methicillin-resistant staphylococci (MRS) are emerging as important pathogens in humans and animals worldwide. The aim of this study was to investigate the prevalence of MRS in the racehorse population and in horserelated personnel in Korea. A total of 195 horses and 18 humans (eight veterinarians, three veterinary hospital staff, and seven horse-handlers) from racehorse farms in Korea were included in the study. The samples were collected from nasal cavities using bacterial transport medium and were cultivated on tryptic soy agar with 5% sheep blood for 3 days at 37oC to confirm the presence of Staphylococcus spp. Presumptive Staphylococcus spp. isolates were identified by 16S ribosomal RNA gene analysis. The coagulase test and oxacillin susceptibility tests were performed using the tube dilution and disk diffusion methods, respectively. The presence of the mecA gene was determined using a polymerase chain reaction assay. Of the 195 horses, 29 (15.6%) yielded 29 MRS isolates. Twelve (66.7%) of the 18 horse-related personnel yielded 12 MRS isolates. All of the MRS isolates from horses or horse-related personnel were identified as methicillin-resistant coagulase-negative staphylococci (MRCNS). The result of this study suggest that the prevalence of MRS increased with the duration of antibiotic use (p = 0.002). This study also provides evidence for the zoonotic transmission of MRCNS between horses and humans, although further investigations are needed.
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- 2014
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49. New Report of Majoid Crab, Pugettia intermedia (Crustacea: Decapoda: Majoidea) from Korea
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Won Kim, Sang-kyu Lee, Tae Seo Park, and Dongsung Kim
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biology ,Pugettia ,Ecology ,Decapoda ,Fauna ,General Engineering ,Energy Engineering and Power Technology ,biology.organism_classification ,Crustacean ,Majoidea ,lcsh:Biology (General) ,new report ,lcsh:Zoology ,lcsh:QL1-991 ,Korean fauna ,Intermedia ,lcsh:QH301-705.5 ,Pugettia intermedia - Abstract
As a result of continuous taxonomic investigations of Korean crabs, Pugettia intermedia Sakai, 1938 is newly reported from Korean waters. Pugettia intermedia had previously been reported in Korean fauna, but the previous reports of P. intermedia were resulted in misidentification of P. quadridens (De Haan, 1839). Pugettia intermedia differs from P. quadridens in having two subequal medial lobes of the first pleopod in male. In P. quadridens, one of the two medial lobes is about half-length of the other. Pugettia intermedia occurs on the southern coast of the Korean peninsula. The descriptions and illustrations of this species are provided herein.
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- 2014
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50. A Therapeutic Strategy for Chemotherapy-Resistant Gastric Cancer via Destabilization of Both β-Catenin and RAS
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Yong Hee Cho, Kang Yell Choi, Jeong Ha Hwang, Sangwoo Kim, Won Ji Ryu, Sang Kyu Lee, Soonmyung Paik, Jae Eun Lee, Mi kyoung Seo, Do Sik Min, Sung Hoon Noh, Jae Ho Cheong, and Gunho Lee
- Subjects
0301 basic medicine ,chemotherapy resistance ,Cancer Research ,Colorectal cancer ,lcsh:RC254-282 ,Article ,degradation of both β-catenin and RAS ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,FOLFOX ,Cancer stem cell ,medicine ,biology ,business.industry ,gastric cancer ,CD44 ,Cancer ,gastric cancer patient-derived xenograft ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,digestive system diseases ,Oxaliplatin ,030104 developmental biology ,Oncology ,Paclitaxel ,chemistry ,030220 oncology & carcinogenesis ,Catenin ,Cancer research ,biology.protein ,business ,medicine.drug - Abstract
Treatment of advanced gastric cancer patients with current standard chemotherapeutic agents frequently results in resistance, leading to poor overall survival. However, there has been no success in developing strategies to overcome it. We showed the expression levels of both &beta, catenin and RAS were significantly increased and correlated in tissues of 756 gastric cancer (GC) patients and tissues of primary- and acquired-resistance patient-derived xenograft tumors treated with 5-fluorouracil and oxaliplatin modulated with leucovorin (FOLFOX). On the basis of our previous studies, where small molecules to suppress colorectal cancer (CRC) via degrading both &beta, catenin and RAS were developed, we tested the effectiveness of KYA1797K, a representative compound functioning by binding axin, in the growth of GC cells. The efficacy test of the drugs using gastric tumor organoids of Apc1638N mice showed that the CD44 and ALDH1A3 cancer stem cell markers were induced by FOLFOX, but not by KYA1797K. KYA1797K also efficiently suppressed tumors generated by re-engrafting the FOLFOX-resistant patient-derived xenograft (PDX) tumors, which also showed resistance to paclitaxel. Overall, the small-molecule approach degrading both &beta, catenin and RAS has potential as a therapeutic strategy for treating GC patients resistant to current standard chemotherapies.
- Published
- 2019
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