• Plant Biotechnology Reports
• /
• 제5권1호
• /
• pp.53-60
• /
• 2011

Artemisinin is effective against both chloroquine-resistant and -sensitive strains of Plasmodium species. However, the low yield of artemisinin from cultivated and wild plants is a serious limitation to the commercialization of this drug. Optimization of artemisinin yield either in vivo or in vitro is therefore highly desirable. To this end, we have overexpressed the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR) gene (hmgr) from Catharanthus roseus L. in Artemisia annua L. and analyzed its influence on artemisinin content. PCR and Southern blot analyses revealed that the transgenic plants showed stable integration of the foreign hmgr gene. The reverse transcriptase-PCR results suggested that the hmgr was expressed at the transcriptional level in transgenic lines of Artemisia annua L., while the high-performance liquid chromatography analysis showed that artemisinin content was significantly increased in a number of the transgenic lines. Artemisinin content in one of the A. annua transgenic lines was 38.9% higher than that in non-transgenic plants, and HMGR enzyme activity in transgenic A. annua L. was also higher than that in the non-transgenic lines.

• KSBB Journal
• /
• 제19권5호
• /
• pp.374-380
• /
• 2004

Production of therapeutic proteins by transgenic plant cell suspension cultures is an attractive system alternative to the other expression system. However, plant cell cultures have shown low expression level of foreign proteins and decreased cell viability by the changes of culture conditions. Therefore, it is necessary to enhance cell viability during the culture period. In this study, a quantitative analysis technique was designed to measure relative cell viability for plant suspension cells which have cell wall and aggregates. It was found that the programmed cell death of plant cells by apoptosis was essentially linked with the apoptotic pathway of animal cells. Therefore, effects of nicotinamide, 3-aminobenzamide and antioxidants on cell viability and apoptosis were examined in transgenic Nicotiana tabacum cells producing hGM-CSF. With those additives, cell viability could be maintained and apoptosis could be redued. In the result, the extracellular production of hGM-CSF could be enhanced 2.5 fold. It was also found that the supplementation of glutathione and ascorbic acid suppressed both the cold stress-induced decrease in cell viability and the increase of total genomic DNA fragmentation.

• Journal of Plant Biotechnology
• /
• 제42권3호
• /
• pp.154-160
• /
• 2015

The plant breeding technology was developed with genetic engineering. Many researchers and breeders have turned from traditional breeding to molecular breeding. Genetically modified organisms (GMO) were developed via molecular breeding technology. Currently, molecular breeding technologies facilitate efficient plant breeding without introducing foreign genes, in virtue by of gene editing technology. Gene targeting (GT) via homologous recombination (HR) is one of the best gene editing methods available to modify specific DNA sequences in genomes. GT utilizes DNA repair pathways. Thus, DNA repair systems are controlled to enhance HR processing. Engineered sequence specific endonucleases were applied to improve GT efficiency. Engineered sequence specific endonucleases like the zinc finger nuclease (ZFN), TAL effector nuclease (TALEN), and CRISPR-Cas9 create DNA double-strand breaks (DSB) that can stimulate HR at a target site. RecQl4, Exo1 and Rad51 are effectors that enhance DSB repair via the HR pathway. This review focuses on recent developments in engineered sequence specific endonucleases and ways to improve the efficiency of GT via HR effectors in plants.

• Journal of Plant Biotechnology
• /
• 제3권2호
• /
• pp.67-81
• /
• 2001

Traditionally, genetic variability is generated by an extensive crossing program, which is complemented by strict selection to identify useful new recombinants. Plant biotechnology offers many opportunities for breeders to solve certain breeding problems at the molecular level. The tissue culture methodology and the genetic modification of economically important monocotyledons have undergone a revolution in the last decade. As the production of transgenic plants is a complex procedure, including the uptake of DNA molecules into the cells, the integration of foreign nucleotide sequences into the host genomic DNA and the expression of new genes in a controlled way, and as there are still many unsolved questions, further development is necessary. The methodology opens up the possibility of introducing novel genes that may induce resistance to diseases and abiotic stresses, allow the modification of dough quality and the dietetic quality of proteins, and increase the levels of micronutrients such as iron, zinc, and vitamins. In the present review, the authors would like to summarise the most important advances in wheat transformation.

• Journal of Plant Biotechnology
• /
• 제5권1호
• /
• pp.19-23
• /
• 2003

The Ac (activator) which is one of the well-characterized transposable elements from maize was examined for its transposition possibility to the heterologous plant (P.nigra x maximowiczii) genome via Agrobacterium tumefacience (LBA4404) mediated transformation system. A number of transgenic plants were successfully recovered after 30 weeks by amount reduction from 50 to 15 g/$m\ell$ kanamycin for in vitro selection to minimize phytotoxic effects and to increase callus growth and regeneration efficiency. Among transgenic plants, 62 out of 106 transgenic poplars (58.5%) showed abnormal phenotypes such as severe serrated leaves and light leaf coloration. Indigo staining with X-gluc proved indirectly the restoration of Gus enzyme function and the presence of Ac in poplar genome by PCR. Southern analysis indicated the transposition and existence of Ac element in poplar genomes. In this research, an Agrobacterium-mediated transformation system in poplar species was developed and identified that Ac derived from maize can be excised and trans posed into other poplar genomes.

• Journal of Plant Biology
• /
• 제37권3호
• /
• pp.371-380
• /
• 1994

To determine the patterns and the levels of expression of the cauliflower mosaic virus (CaMV 35S) promoter and the rice actin 1 (Act1) promoter in rice, transgenic rice plants containing CaMV 35S-$\beta$-glucuronidase (GUS) and Act1-GUS constructs were generated and examined by fluorometric and histochemical analyses. The fluorometric analysis of stably transformed calluses showed that the activity of the rice Act1 promoter was stronger than that of the CaMV 35S promoter in rice cells. In a histochemcial study of the transgenic rices, it was shown that the GUS activity directed by the CaMV 35S promoter was localized mainly in parenchymal cells of vascular tissues of leaves and roots and mesophyll cells of leaves. These results are similar to those of potato, a dicot plant. In contrast, rice plant transformed with Act1-GUS fusion construct revealed strong GUS activity in parenchymal cells of vascular tissue, mesophyll cells, epidermal cells, bulliform cells, guard subsidiary cells of leaves and most cells of the root, suggesting that the rice Act1 promoter is more constitutive than the CaMV 35S promoter. It was also confirmed that in both types of transgenic rice little or no staining was localized in metaxylen tracheary elements of vascular tissue from leaves or roots. These results indicate that the rice Act1 promoter can be utilized more successfully for expression of a variety of foreign gene in rice than the CaMV 35S promoter.

• 한국응용곤충학회지
• /
• 제43권1호
• /
• pp.81-84
• /
• 2004

복숭아의 주요 식물기생성선충 종류를 밝히기 위하여 2000년부터 2002년까지 3년간 경북지역의 124개 복숭아 과원 토양으로부터 선충을 분리하고 선충의 종류, 밀도, 빈도(Frequency), 우점도(Simpson's index), 다양성지수(Shannon and Wiener index), 중요도(Prominence value)를 분석하였다. 식물기생성 선충은 총 124지점 중 97지점에서 발견되었으며 우점도는 0.717-0.881, 다양성지수는 0.221-0.286로 복숭아는 다양한 종류의 식물기생성선충에 의하여 피해를 받기보다는 몇몇 우점하고 있는 식물기생성선충에 의하여 피해를 받고 있었다 복숭아과원에서 중요한 식물기생성선충은 Tylenchorhynchus nudus, Criconemoides informis, Paratylenchus elachistus, Pratylenchus vulnus, Helicotylenchus digonichus 순이었고, 그 외 Aphelenchus sp., Tylenchus sp., Heterodera sp., Scutellonema sp. 등이 검출은 되었으나 중요종은 아니었다. 이번 조사에서 특히 국내 복숭아과원 토양에는 Paratylenchus elachistus가 널리 분포하고 있었으며, 반면 외국에서 심각한 문제가 되고 있는 뿌리혹선충류는 발견되지 많았다.

• 한국조경학회지
• /
• 제23권2호
• /
• pp.113-123
• /
• 1995

This study was conducted to find out appropriate rates of seed mixture of both native and foreign plants in order for stabilization of early afforestation and proper vegetation on road slope. The results are summarized as follows: 1. Characteristics of germination : After seeding, 2 weeks for both Lespedeza bicolor and Lespedeza cuneata, and 4 weeks for both Arundinella hirta and Zoysia japonica were needed for vigorous germination, and 1-4 wee17s for 3 cool-season grasses were spent for gradual germination. 2. Plant height : There was no difference between Lespedeza cuneata and Lespedeza bicolor in plant height by 7 treatments. As mixture rates of cool-season grasses were lowered, plant height of Arundinella hirta became longer. Descending order of co81-season grasses for plant height was Tall fescue, Perennial ryegrass and Creeping redfescue. 3. Number of tillers : The number of tillers tended to increase in the experimental plots where competition was low. 4 Ground cover rate : Ground cover rate was the highest in Mixture IV (96.7%) and was fluctuated from 13.3% on Sept. 13 to 45% on Nev. 3 in Mixture III. Descending order of gronud cover rates in 7 treaments was Mixture IV, Mixture III. Mixture II, Mixture Ⅶ, Mixture V, Mixture Ⅵ, Mixture I, and Mixtur III when measured on Oct. 13 5. Visual assessment: High preferences were observed on Mixture IV and Ⅶ In sun the best seed mixtures were Mixture IV and Ⅶ. It meant that (1) either mixture of 70% the native plants with 30% cool-season graaes or (2) mixture of 80% the native plants with 20% cool-season glasses was best for this study.

• 한국산업융합학회 논문집
• /
• 제23권6_2호
• /
• pp.1081-1091
• /
• 2020

The most recent issue of offshore plants that produce oil and gas are the decommissioning engineering of aged or discontinued platforms. There are many platforms that are being dismantled in the United States, Europe, and areas in Southeast Asia. In particular, more than 400 old platforms in Southeast Asia (Indonesia, Malaysia) are preparing to dismantle. They are spread out across Southeast Asia with a water level of 50 meters and small-scale of less than 10,000 tons. However, this offshore plant decommissioning market is a very suitable market for small and medium-sized shipyards in Korea to enter with their established equipment and engineers. Platform decommissioning is conducted according to decommissioning procedures. However, there are some difficulties in market advances as no developed case studies or process models are established on how platform structures and components are to be dismantled and how the dismantled material is to be reused and recycled. Therefore, this study presented domestic and foreign regulations on the reuse and recycling of oil and gas producing offshore plant platforms, case analyses on developed decommissioning engineering, platform reuse and recycling guidelines, and platform and pipeline decommissioning processes and methods.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
• /
• pp.146.2-147
• /
• 2003

Two Korean isolates of Alfalfa mosaic virus (AHV-AZ, AMV-KR) were isolated from azuki bean and potato plants, respectively, and their pathologies were confirmed on some susceptible host plants including pepper, tobacco and red bean plants. Full length cDNAs to RNA1, RNA2 and RNA3 of the two Korean strains were amplified using the long-template reverse transcription (RT)-polymerase chain reaction (PCR) method. RT-PCR products covering entire regions for the three AMV genome RNAs were cloned. RNA transcripts were synthesized in vitro from each clones using T7 RNA polymerase and infectivity test was peformed in 9 reassortment sets of transcripts. All the combinations of reassorted transcripts were found to be infectious when inoculated onto Nicotiana benthamiana plants, and were not distinguishable to those of wild types. The full-length cDNA clones that were confirmed infectious were sequenced their nucleotide sequences. We will discuss sequence analysis of the two Korean isolates of AMV genomic RNA3 and compare reported foreign isolates of AMV.