Investigation of Agrobacterium-mediated Transient dsRNA Expression in Tobacco

최원균,임혜송,서한규,김동욱 한국하천호수학회 2019 생태와 환경 Vol.52 No.4

The Agrobacterium tumefaciens mediated gene transfer is widely used to generate genetic transformation of plants and transient assay of temporal exogenous gene expression. Syringe infiltration system into tobacco (Nicotiana benthamiana) leaves is a powerful tool for transient expression of target protein to study protein localization, protein-protein binding and protein production. However, the protocol and technical information of transient gene expression, especially double strand RNA (dsRNA), in tobacco using Agrobacterium is not well known. Recently, dsRNA is crucial for insecticidal effect on destructive agronomic pest such as Corn rootworm. In this study, we investigated the factor influencing the dsRNA expression efficiency of syringe agro-infiltration in tobacco. To search the best combination for dsRNA transient expression in tobacco, applied two Agrobacterium cell lines and three plant vector systems. The efficiency of dsRNA expression has estimated by real-time PCR and digital PCR. As a result, pHellsgate12 vector constructs showed the most effective accumulation of dsRNA in the cell. These results indicated that the efficiency of dsRNA expression was depending on the kind of vector rather than Agrobacterium cells. In summary, the optimized combination of transient dsRNA expression system in tobacco might be useful to in vivo dsRNA expression for functional study and risk assessment of dsRNA.

Application of simple and massive purification system of dsRNA in vivo for acute toxicity to Daphnia magna

최원균,임혜송,김진,류성민,이정로 한국곤충학회 2018 Entomological Research Vol.48 No.6

The RNA interference (RNAi) has been considered as an important genetic tool and applied to develop a new living modified (LM) crop trait which is an improvement of nutrient quality or pest management. The RNAi of DvSnf7 has been used for resistance to LM maize and the Western Corn Rootworm which is a major agricultural pest for the US Corn Belt. Most of the environmental risk assessments (ERA) of double strand RNA (dsRNA) have been performed using in vitro transcript products, and not in vivo expressed product. A large amount of dsRNA was required for the acute toxicity assay of water fleas. Therefore development of massive dsRNA purification techniques is critical. Daphnia, a freshwater microcrustacean, is a model organism for studying cellular and molecular mechanism involved in life history traits and ecotoxicology. In this study, we established the massive dsRNA purification method using Escherichia coli and implemented acute toxicity assays to Daphnia magna. As a result, the present RNase A and DNase I, dsRNA was efficiently purified without any special techniques or equipment. Even though purified dsRNA existed during the acute toxicity test, lethality or abnormal behavior were not observed in D. magna. These results indicated that GFP and DvSnf7 dsRNA were not significantly affected to D. magna due to their lack of sequence matching in its genome. The purification method of dsRNA and the acute toxicity assay of water fleas using purified dsRNA would be suitable for the toxicological studies of LMOs to aquatic non‐target organisms.

Study of low-thermal-expansion porcelain employing petalite and β-eucryptite

최원균,강태성,김남일,이상진 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.3

Clay mixtures with petalite or β-eucryptite were studied with the aim of obtaining thermal shock resistant porcelain. β- eucryptite was synthesized by mixing Li2CO3 and Al(OH)3 with silica in stoichiometric compositions, and the synthesized β- eucryptite showed a thermal expansion coefficient of −7.10 × 10-6/ o C. The final phase and coefficient of thermal expansion of the fired petalite-clay and eucryptite-clay samples were examined according to changes of the mixing ratio and firing temperature. In the petalite-clay samples, lithium alumina silicate (Li2O • Al2O3 • 7.5SiO2) and keatite-type β-spodumene, which shows a positive thermal expansion coefficient, were observed. In the eucryptite-clay samples, β-quartz-type β- spodumene was well developed according to the increase of eucryptite content and firing temperature. Under the conditions of 70 wt% eucryptite content and at a firing temperature of 1350 o C, the eucryptite-clay sample yielded a low thermal expansion coefficient of 0.7 × 10-6/ o C. The mixing of β-eucryptite into clay enabled the realization of excellent thermal shock resistant porcelains.

모세관 전기영동을 이용한 DNA 단편의 분석

최원균,조재선 慶熙大學校 大學院 1994 高凰論集 Vol.14 No.-

Capillary electrophoresis(CE) is a versatile microanalytical technique that has gained much attention, particularly from those working with biologically active molecules. Its appealing characteristics include unprecedented sensitivity and the ability for automating the rapid electrophoretic separation of a number of low volume samples in a reproducible manner, with relarively short analysis times. The picomole femtomole sensitivity of UV CE has been enhanced tremendously by the interfacing of detection systems such as laser induced fluorescence, which has extended the sensitivity into the attomole-zepptomole range. This paper is CE research of DNA analysis and development has taken on directions focused primarily on improving detection, understanding and exploiting the basic chemistry of CE and devising new applications.

이란산 흑석류 농축액과 그 제품의 성분 및 함유된 Phyto 에스트로겐류에 관한 연구

최원균,정교순,조규성,황명오,유영숙 한국식품영양학회 2002 韓國食品營養學會誌 Vol.15 No.2

천연 호르몬 보충 제제의 개발을 위한 기초 연구로 이란산 흑석류 과즙 농축액과 이를 이용한 제품의 화학성분들을 분석하였다. 석류 농축액의 일반성분은 수분 39.3%, 조지방 0.4%, 조단백질 0.9%, 조회분 1.4%, 그리고 탄수화물은 42.0%이었다. 아미노산 함량은 글루탐산이 1310.Oppm, 아스파르트산이 896.2ppm, 아르기닌이 877.7ppm, 페닐알라닌이 57.5ppm순으필 무기 성분들은 철분 6640.Oppm, 염소 3464.Oppm, 칼륨 2550.8ppm, 인 150.Oppm, 칼슘 80.Oppm 순으로 많이 함유되 어 있었다 비타민은 5가지의 수용성 비타민이 함유되어 있었으며 그 중 비타민 C(20mg/100g)를 제외한 나머지 비타민들이 아주 적은 양이 있었다. 주요 지방산은 palmitic acid(8.3%)와 stearic acid(69.4%)로 전체 지방산의 약 60~80%를 차지하고 있었다. 또한 6종의 phyto및 에스트로겐류가 들어 있었으며 각각daidzein 23.72ppm, quercetin 9,75ppm, catechin 1.48ppm, genistein 0.29ppm, 2,3-di-MeO-estradiol이 0.04ppm, 그리고 17β-에스츠라디올이 0.15ppm이 함유되어 있었다. 이상의 결과들을 석류 농축액으로 제조한 제품 포에버 120과 칡과 대두 isoflavon 농축분말과 비교하다. Phytoestrogens are non-steroidal compounds found in a variety of plants, which exert estrogenic effects in animals. In this study, the physico-chemical properties of Iranian black pomegranate extract and its products as preliminarily research for the developing of natural estrogen supplement were evaluated. The chemical components of Iranian black pomegranate extracts and its product (Forever 120) were analyzed. Proximate compositions of pomegranate extracts were as follows; crude lipid 0.4%, crude protein 0.9%, crude ash 1.4% and carbohydrate 42.0%. Major amino acids of pomegranate extracts are glutamic acid (1310.Oppm), aspartic acid (896.2ppm), arginine (877.7ppm) and phenylalanine (57.5ppm). Fatty acid compositions of pomegranate extract lipid extracted by chloroform-methanol (2:1) were myristic (13.1%), stearic (69.4), oleic acid (6.8%) and palmitic acid (8.3%). Mineral elements were ferrous (6640.Oppm) and potassium (2550.8ppm). Vitamins were composed of ascorbic acid(20.Omg/100g), Vit. B_1 (0.12mg/100g) and niacin (0.80mg/100g), 20 phytoestrogens and 20 estrogens of pomegranate extracts were detected Daidzein (0.29ppm), quercetin (9.75ppm) genistein (0.29ppm) and 17 β-estradiol(0.15ppm). Above the chemical components of pomegranate extracts were compared with that of pome granate its product or other isoflavon concentrates.

비선형 등온흡착 시스템의 이성분 동시농축

최원균,서성섭 ( Won Gyun Choi,Sung Sup Suh ) 한국화학공학회 1996 화학공학의이론과응용 Vol.2 No.2

Development and application of a novel multiplex PCR method for four living modified soybeans

최원균,설민아,조범호,김일룡,이정로 한국응용생명화학회 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.6

Since the early 1990s when the first commercialization of living modified organism (LMO), LMO has been developed to improve nutrient quality and productivity of crops. As the self-sufficiency rate of soybean has gradually decreased in South Korea, most of soybeans have been imported. The cultivation and trade of LM crops are regulated in many countries and authorizations for the use are mandatory in most. In South Korea, the cultivation of LM crop is not allowed and unintentional release of LMO into the natural environment is prohibited. In this study, we developed a novel multiplex PCR method for four LM soybean events (CV127, MON87705, FG72 and MON87701) which were approved recently in South Korea. Multiplex PCR primers were designed for PCR amplification of four LMO event-specific fragments, and we analyzed 41 environmental monitoring samples to confirm the efficiency of this method. These results indicated that the multiplex PCR detection method is sufficient for four LM soybeans found in the natural environment. Based on our finding, we suggest that the new technique may be useful as a lead tool for the development of a detection method for various LMO/GMOs.

Dimethylglutarylation 에 의한 변형대두단백질의 기능적 특성

최원균,정철원 한국식생활문화학회 1999 韓國食生活文化學會誌 Vol.14 No.5

MuZero 강화학습을 이용한 항만 컨테이너 재정돈 계획

최원균,이기주,채준재 한국물류과학기술학회 2021 물류과학기술연구 Vol.2 No.2

This study provides a new solution approach for container pre-marshalling problems using a reinforcement learning method, the MuZero Algorithm. We have developed a customized pre-marshalling environment for an agent to be trained. To facilitate the training, we have devised i) some action masking methods, and ii) a reward function where lower bound for the number of rehandling is considered. Action masking methods and heuristically found lower bound were proven to be helpful in the learning process. Experiments with different sizes (from the minimum number of 8 and the maximum number of 12 containers) were carried out, within a stacking space of six rows and six tiers. Experimental results show that the MuZero algorithm implemented with our strategy is capable of training to solve the pre-marshalling problems for some small sized problems.

Dimethylglutarylation 에 의한 변형대두단백질의 물리화학적 특성

최원균,정철원 한국식생활문화학회 1999 韓國食生活文化學會誌 Vol.14 No.5