• Molecules and Cells
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• 제28권1호
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• pp.57-65
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• 2009

CDC48 is a member of the AAA ATPase superfamily. Yeast CDC48 and its mammalian homolog p97 are implicated in diverse cellular processes, including mitosis, membrane fusion, and ubiquitin-dependent protein degradation. However, the cellular functions of plant CDC48 proteins are largely unknown. In the present study, we performed virus-induced gene silencing (VIGS) screening and found that silencing of a gene encoding a tobacco CDC48 homolog, NgCDC48, resulted in severe abnormalities in leaf and shoot development in tobacco. Furthermore, transgenic tobacco plants (35S:anti-NgCDC48), in which the NgCDC48 gene was suppressed using the antisense RNA method, exhibited severely aberrant development of both vegetative and reproductive organs, resulting in arrested shoot and leaf growth and sterile flowers. Approximately 57-83% of 35S:anti-NgCDC48 plants failed to develop mature organs and died at early stage of development. Scanning electron microscopy showed that both adaxial and abaxial epidermal pavement cells in antisense transgenic leaves were significantly smaller and more numerous than those in wild type leaves. These results indicate that NgCDC48 is critically involved in cell growth and development of tobacco plants. An in vivo targeting experiment revealed that NgCDC48 resides in the endoplasmic reticulum (ER) in tobacco protoplasts. We consider the tantalizing possibility that CDC48-mediated degradation of an as-yet unidentified protein(s) in the ER might be a critical step for cell growth and expansion in tobacco leaves.

• Journal of Plant Biotechnology
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• 제31권4호
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• pp.313-317
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• 2004

MMPs는 $Zn^{2+}$-의존성 endopeptidase로서 세포외 기질을 분해하는 능력을 갖고 있다. 본 연구에서는 담배식물체에서 잎의 발생단계별로 분비되는 MMPs의 활성과 환경 스트레스에 의한 MMPs의 활성을 조사하였다. 그 결과 MMPs의 활성은 기부 부위의 완전히 성숙한 잎보다 엽신의 확장이 일어나고 있는 어린잎에서 높았다. 이는 식물체에서 잎 신장을 위한 세포내 공간 형성 및 조직재구성에 MMPs가 중요한 단백질분해효소로 작용함을 시사하였다. 또한 환경 스트레스에 대한 반응으로서 MMPs의 활성을 조사한 결과 염처리와 병원균 감염에 의해 각각 1.2배와 1.5배의 증가를 보였다. 이러한 결과는 식물체가 발생단계 외에도 불리한 환경에 대한 방어 수단으로 MMPs가 생성 분비함을 알 수 있었다.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2006년도 한국육종학회 공동심포지엄 및 학술대회
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• pp.36.1-36.1
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• 2006

• 한국연초학회지
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• 제15권1호
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• pp.63-74
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• 1993

Changes in the amount of ribulose 1, 5-bisphosphate carboxylase/oygenase(=RuBisCO) protein, namely fraction I protein, and the protease activity were determined in the 10th leaf of tobacco(Nicotiana tabacum, var. Ky-57) from 10 days after emergence through senescence at 5 days interval. The amount of RuBisCO per deveined leaf rapidly increased during the early growing season, reached a maximal quantity at the around 20 days after leaf emergence, when the leaf has gone through its most rapid expansion, and began gradually to decrease till 30 days after leaf emergence, thereafter significantly declined to 45 days that the leaf has been dried up partly. The pattern of the ratio of RuBisCO protein to soluble protein in quantity changed similar to that of RuBisCO contents in a leaf, that was 43%, 60%, and 21% at the around 10 days, 20 days, and 45 days, respectively. And RuBisCO contents was linearly correlated with the concentration of chlorophyll(r=0.98) throughout the life span of the leaf. So, it was assumed that the leaf color can be a useful indicator for judging whether RuBisCO contents higher or not in tobacco leaves without homogenization. On the other hand, the protease activities for degradation of casein were assayed at pH 5.5. 7.0. and 8.5 with crude extracts desalted on Sephadex G-25. The highest caseolytic activity was found at pH 5.5 throughout the life sawn of the leaf. Also, the activity at 5.5 became gradually to increase from 30 days after leaf emergence, when RuBisCO protein had became to disappear and remarkably increased in the last stage of senescence, although nitrogen contents of the leaf had reached low levels. The caseolytic activity at pH 5.5 was in negative correlation with RuBisCO contents throughout the life span of the leaf, but not in lineality between them. In other words, the caseolytic activity increased in a rapid exponential manner when RuBisCO contents had reached some low levels. These results showed that the leaf age, namely harvesting time, is a very important factor for the production of the tobacco leaf containing higher RuBisCO protein. It was concluded that the practical harvesting time is between 20 days and 30 days after the leaf emergence from the present results.

• 공업화학
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• 제20권4호
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• pp.363-369
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• 2009

오일 가격의 폭등에 따른 바이오디젤 사용량의 증가로 인해 글리세롤 부산물의 공급과잉이 유발되었다. 원래 글리세롤은 석유화학,페인트,담배, 생활용품 및 화장품 분야에 원료자체로써 사용되어 왔다. 최근에는 글리세롤을 값싼 원료로 사용하여 고부가가치의 기능성 물질을 개발하는 응용 연구를 통해 고부가가치의 유도체 물질로 상용화되는 사례가 많이 보고되고 있다. 본 총설에서는 글리세롤을 원료로 사용하여 새로운 고부가 글리세롤 유도체로 개발한 연구동향을 검토해 보았다.

• 화약ㆍ발파
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• 제38권4호
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• pp.26-36
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• 2020

지하공간의 이용범위 확장 및 활용이 증가함에 따라 테러리스트들에 의한 지하 내부 폭발의 발생 가능성이 증가하고 있다. 본 연구에서는 심도 50m의 심도에 굴착된 원형 터널을 모델링한 후, 터널의 내부에 폭발하중을 가하였다. 폭발하중은 ATF(Bureau of Alcohol, Tobacco, and Firearms)에서 제시하는 6종류의 운반용 차량에 대한 최대 폭약량의 폭발하중을 산정하였다. 원형 터널 주변 지반은 국내 터널 설계에서 제시하는 지보패턴에 따른 3종류의 암반등급을 선정하였다. 비선형 동적해석을 수행하여 폭발하중과 지반 특성을 매개변수로 지표 변위를 분석하여 지상 구조물의 영향에 대해 평가하였다. 해석결과, 1등급암에 대해서는 지반의 융기에 대한 영향을 고려해야 하며, 2등급암과 3등급암은 부등침하에 대한 영향을 고려해야 한다. 특히, 3등급암은 40m 이내의 지상 구조물에 대해서는 정밀 분석이 요구된다. 또한 지표 변위는 탄성계수에 의한 영향이 주요인인 것으로 판단된다.

• 한국작물학회지
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• 제34권s01호
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• pp.4-15
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• 1989

식물홀몬을 포함한 각종 식물생장조절물질의 생검법(bioassays or biological assays)을 소개 및 비교검토함과 동시에 일관성 있는 결과를 얻기 위한 몇가지 유의점을 지적코자 옥신류 생검에서는 녹두발근과 귀리제1절간장신장, gibberellin에서는 왜성벼의 제2엽신장과 왜성완두의 상조축신장, 그리고 cytokinin류에서는 무자엽생장, 담배줄기수캘러스생장, 그리고 오이자엽내엽록소형성 등의 방법을 요약하였다. 아울러 일련의 실험을 통해 얻어졌던 각종생장조절물질(특히 최근에 개발되는 각종 왜화제)에 대한 반응을 홀몬별로 요약 및 비교하였다.

• Journal of Ginseng Research
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• 제21권1호
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• pp.13-18
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• 1997

Identification and changes of physiologically active substances during chilling storage of dehisced ginseng (Panax ginseng C. A. Meyer) seeds were analyzed using various preparatory separation methods and purification columns; Dowex 50W and silica gel columns. Seven components with Rf values of 0.20, 0.40, 0.58, 0.66, and 0.70 In solvent system, $CHCl_3$:MeOH=3:1 (v/v), Rf values of 0. 63 and 0.74 in solvent system, $CHCl_3$:MeOH:$H_2O$:=7:3:1 (v/v) were obtained through Dowex 50W and silica gel column chromatographies. Two components with Rf values of 0.20 and 0.63 in the all chilling treatments were detected in the extract obtained through both chromatographies, and only the former component was gradually increased till 4 weeks of chilling storage and then rapidly decreased from 8 to 16 weeks. UV spectra of Rf values of 0.66 and 0.56 were similar to that of cytokinin, but their physiological activities were not found. Rf values of 0.20 showed activity by radish cotyledon expansion bioassay. The component with Rf value of 0.20 was revealed to have a naphthalene in the proposed chemical structure by various NMR techniques.

• 한국학교ㆍ지역보건교육학회지
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• 제18권3호
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• pp.107-121
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• 2017

Objectives: Given that the expansion of smoking cessation regulations in Korea generates great demand for smoking cessation services, healthcare professionals should be up skilled to make an important contribution to tobacco control. This study was aimed to develop a smoking cessation education program for nursing students and to try to find possible ways to incorporate the smoking cessation education in their regular course program. Methods: One group pre- & post-test design was used. The subjects were 70 nursing students from two universities in S and D city. Subjects were participated in a four-hour smoking cessation education program developed for increasing knowledge, competency, and self-efficacy for smoking cessation counselling. Data were analysed with descriptives and paired t-tests. Results: The developed education program for smoking cessation counselling produced a substantial effects in terms of knowledge, competency, and especially for self-efficacy for smoking cessation counselling. Conclusions: Smoking cessation advices and support from health professionals are key aspects of a comprehensive approach to smoking cessation. Incorporating the smoking cessation education program developed in this study in the regular baccalaureate program for nursing students may help increase the involvement of nurses in cessation counseling upon graduation.

• The Plant Pathology Journal
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• 제22권2호
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• pp.119-124
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• 2006

Kudzu vine(Pueraria montana var. lobata) is an invasive climbing woody vine that envelops trees and shrubs, pressing physically and shutting out sunlight, which needs to be controlled. Kudzu vine pathogens were surveyed as a way to seek its biocontrol agents in 2002. Occurrence of a bacterial halo blight disease of kudzu vine was observed at several localities in Korea including Euiwang and Suwon in Gyeonggi Province, Daejon, and Gochang and Buan in Jeonbuk Province. Symptoms of brown to black spots with a surrounding yellowish halo appeared from June and lasted till the rainy season without much expansion, but accompanying often leaf blight and defoliation. Isolated bacteria were identified as Pseudomonas syringae pv. phaseolicola based on physiological and cultural characteristics, Biolog, fatty acid and 16S rDNA sequencing analyses. In artificial inoculation test, these bacteria produced the same halo spot symptoms on kudzu vine and bean plants. They also induced hypersensitive responses (HR) on tobacco, tomato, and chili pepper leaves. This is the first report of a bacterial disease of kudzu vine in Korea, and the bacterial pathogen can be used as a biocontrol agent against the pest plant.