• 한국약용작물학회지
• /
• 제8권3호
• /
• pp.243-249
• /
• 2000

RAPD 분석을 통한 marker선별과 건조약재의 비교, 그리고 내부형태 특징을 통해 당귀3종(種)을 구별할 수 있는 결과를 요약하면 다음과 같다. 1. 50개의 primer중 5개의 primer에서 당귀류 3품종을 모두 구별할 수 있는 특이적인 band가 나타났다. 2. 유연관계 분석에서 중국당귀와 일당귀가 참당귀보다 더 근연관계임을 알 수 있었다. 3. 신선한 잎과 건조된 약재에서 RAPD 재현성이 확인되어 RAPD 분석법을 통해 당귀감별에 응용할 수 있을 것으로 사료된다. 4. 뿌리 내부구조에서 중국당귀는 정상적인 2기사부와 2기목부에 덧붙여 일부 이상비대생장을 보였고, 일당귀나 참당귀의 도관절에 비하여 더 넓고 짧아 계통학적으로 훨씬 더 진화된 것으로 여겨진다. 5. 일당귀는 현저하게 두꺼운 코르크층이 발달한 반면 참당귀의 코르크층 아래에 $5{\sim}7$층의 후각세포층이 환상으로 발달하여 뚜렷한 대조를 이루었다.

• 한국약용작물학회지
• /
• 제15권2호
• /
• pp.100-104
• /
• 2007

A protocol for the production of transgenic Panax ginseng C.A. Meyer was established via Agrobacterium tumefaciens-mediated genetic transformation of direct somatic embryos. A number of conditions related to the co-cultivation were tested with respect to maximizing transformation efficiency. The results showed that pH of the co-cultivation medium (5.7), the bacterial growth phase (optical density; $OD_{600}$ = 0.8), co-cultivation period (3 days), and acetosyringone concentration $(100\;{\mu}M)$ had positive effects on transformation. Selected plantlets were cultured on the medium at an elevated hygromycin level(30 mg/l). Integration of the transgenes into the P. ginseng nuclear genome was confirmed by PCR analysis using hpt primers and by Southern hybridization using hpt-specific probe. The transgenic plantlets were obtained after 3-month cultivation and did not show any detectable variation in morphology or growth characteristics compared to wild-type plants.

• 농업과학연구
• /
• 제46권4호
• /
• pp.885-895
• /
• 2019

Plant biotechnologists have long dreamed of technologies to manipulate genes in plants at will. This dream has come true partly through the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, which now has been used to edit genes in several important crops. However, there are many restrictions in editing a gene precisely using the CRISPR/Cas9 technology because CRISPR/Cas9 may cause deletions or additions in some regions of the target gene. Several other technologies have been developed for gene targeting and precision editing. Among these, base editors might be the most practically and efficiently used compared to others. Base editors are tools which are able to cause a transition from cytosine into thymine, or from adenine into guanine very precisely on specific sequences. Cytosine base editors basically consist of nCas9, cytosine deaminase, and uracil DNA glycosylase inhibitor (UGI). Adenine base editors consist of nCas9 and adenine deaminase. These were first developed for human cells and have since also been applied successfully to crops. Base editors have been successfully applied for productivity improvement, fortification and herbicide resistance of crops. Thus, base editor technologies start to open a new era for precision gene editing or breeding in crops and might result in revolutionary changes in crop breeding and biotechnology.

• 한국연초학회지
• /
• 제28권2호
• /
• pp.100-110
• /
• 2006

A mutant of Potato vims Y (PVY) was occurred in PVY resistance flue-cured tobacco breeding line KF0402 $(TC1146{\times}KF117)$ showing vein necrosis at Suwon in Korea. This isolate, PVY-SWM, was differentiated from other PVY based on biological properties and nucleotide sequence analyses of coat protein gene. PVY-SWM caused typical symptoms on 21 indicator plants as compared to the PVY-TOJC37. Remarkably, the PVY-SWM induced distinctly different symptom of systemic vein necrosis on tobacco cultivars V.SCR, PBD6, TN86, TN90, Virgin A Mutant (VAM), Wislica, NC744, KB108 and KB111, which were reported to have the recessive potyvirus resistance gene va. In RT-PCR assays with specific primers for detection of PVY, a single band of about 800bp in length was produced. The amplified DNA was cloned and the nucleotide sequence was determined. The coat protein gene of PVY-SWM showed 88.4%-99.0% and 92.5%-98.5% identities to the 12 different PVY isolates of Genbank Database at the nucleotide and amino acidi respectively. Multiple alignments as well as cluster dendrograms of PVY-SWM isolate revealed close phylogenetic relationship to the $PVY^{NTN}$ subgroup.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVII)
• /
• pp.434-438
• /
• 2005

생물반응기의 운전 특성과 성능은 온도나 pH, 용존산소 등의 물리화학적 조건 외에 미생물의 종류와 분포비율, 미생물의 대사상태에 따라서도 매우 다양한 특성을 보인다. 질산화 미생물 코팅 담체를 투입한 반응조에서는 담체가 없는 반응조에 비해 질산화 미생물의 양이 증가하였고, 또한 질산화 미생물이 코팅된 담체를 사용한 반응기는 코팅되지 않은 담체를 투입한 반응조에 비해 질산화 미생물 양의 상승효과가 있었다. 질산화 미생물의 양은 운전 기간과 수온의 상승에 따라 증가하는 것으로 나타났다.

• 한국세라믹학회지
• /
• 제47권6호
• /
• pp.583-589
• /
• 2010

In this paper, the properties of reclaimed ash(RA) from various domestic thermal power plants(S, D and H) were analyzed, and the possibility of fabricating the artificial lightweight aggregate(ALA) using RA was studied. The chemical compositions of RA are similar to the clay, but it had higher concentrations of alkali earth metal oxides(CaO, MgO) and unburned-carbon. The TCLP(Toxicity Characteristic Leaching Procedure) results showed that the dissolution concentrations of heavy metal ions of RA were below the limitation defined by the enforcement regulation of wastes management law in Korea. The results of IC analysis showed that leaching concentration of $Cl^-$ ion was 124 ppm for RA of HN and ${SO_4}^{2-}$ ion was leached a few hundreds ppm for all RA in this study. The ALAs with various mass ratio of clay to reclaimed ash(RA:Clay = 7:3, 6:4, 5:5, 4:6, 3:7) were sintered with a electric muffle furnace at the temperature of $1050{\sim}1200^{\circ}C$. The specific gravity and water absorption(%) of the sintered ALAs were 1.1~1.8 and 10~30% respectively. The ALA sintered in the rotary kiln at $1125^{\circ}C$ showed a bulk density of 1.7 and water absorption of 15.2%.

• KDI Journal of Economic Policy
• /
• 제29권3호
• /
• pp.75-109
• /
• 2007

본 연구는 1993~2003년 기간 중 통계청의 "광공업통계조사보고서"의 원자료에 포함되어 있는 개별 사업체 수준의 패널자료를 이용하여 수입관세의 변화가 우리나라 개별 사업체의 생산성에 미치는 영향을 실증분석하고 있다. 분석 결과에 따르면, 첫째 분석기간 중 우리나라 제조업 전반의 생산성 변화는 산업 내 혹은 산업간 자원이동에 기인했다기보다는 개별 사업체 내부의 생산성 변화에 의해 결정된 것으로 나타났다. 둘째, 수입관세장벽이 낮을수록 개별 사업체의 총요소생산성 증가율이 높은 것으로 나타났다. 이는 관세 장벽의 철폐를 통한 수입시장의 개방이 국내시장에서의 경쟁을 촉진함으로써 개별 기업으로 하여금 생산 경영의 비효율성을 줄이고 기업의 혁신역량을 배양하는 유인으로 작용한 데 기인하는 것으로 사료된다. 셋째, 연도별로는 관세율 인하 후 첫 번째 연도의 생산성 증가율이 가장 높은 것으로 나타나 사업체들이 비교적 짧은 기간 내에 관세 변화에 적응하는 것으로 나타났다. 반면, 고용의 경우에는 관세율 인하 후 차기연도 내에는 통계적으로 유의한 수준의 고용 변화가 감지되지 않지만, 이후 고용증대효과가 서서히 나타나는 것으로 분석되었다.

• Molecules and Cells
• /
• 제27권3호
• /
• pp.351-357
• /
• 2009

Phytoestrogens are the natural compounds isolated from plants, which are structurally similar to animal estrogen, $17{\beta}$-estradiol. Tectoridin, a major isoflavone isolated from the rhizome of Belamcanda chinensis. Tectoridin is known as a phytoestrogen, however, the molecular mechanisms underlying its estrogenic effect are remained unclear. In this study we investigated the estrogenic signaling triggered by tectoridin as compared to a famous phytoestrogen, genistein in MCF-7 human breast cancer cells. Tectoridin scarcely binds to ER ${\alpha}$ as compared to $17{\beta}$-estradiol and genistein. Despite poor binding to ER ${\alpha}$, tectoridin induced potent estrogenic effects, namely recovery of the population of cells in the S-phase after serum starvation, transactivation of the estrogen response element, and induction of MCF-7 cell proliferation. The tectoridin-induced estrogenic effect was severely abrogated by treatment with U0126, a specific MEK1/2 inhibitor. Tectoridin promoted phosphorylation of ERK1/2, but did not affect phosphorylation of ER ${\alpha}$ at $Ser^{118}$. It also increased cellular accumulation of cAMP, a hallmark of GPR30-mediated estrogen signaling. These data imply that tectoridin exerts its estrogenic effect mainly via the GPR30 and ERK-mediated rapid nongenomic estrogen signaling pathway. This property of tectoridin sets it aside from genistein where it exerts the estrogenic effects via both an ER-dependent genomic pathway and a GPR30-dependent nongenomic pathway.

• Toxicological Research
• /
• 제19권1호
• /
• pp.1-12
• /
• 2003

New breeding method by genetic engineering is expected as a key technology to solve food shortage due to the growing world population in the year 2000s. Many genetically modified organisms (GMOs) were already developed and the commercial cultivation had started. The first GMO, Flavr Savr tomato, which rotted at a much slower pace than ordinary ones, was developed in US in 1994. Since then, over than 70 different agricultural products including corn, cotton, soybean, papaya, potato, and squash made with genetically modified plants are reportedly on sale worldwide. Supporters favor the GMOs because they have greater yields, longer shelf lives and stronger resistance to disease and insects. On the other hand, opponents say that the supporters ignore a potential danger that they may damage the environment as well as human beings. To assure the safe development and use of GMOs as food and other biotech products, the possible risks on biological environment and human health should be throughly examined and regulated by developer and government. Because the biosafety problem is a global, environmental, and trade issue, a new international treaty is under development. The Cartagena Protocol on Biosafety was adopted at the 1 st Extraordinary Conference of Parties of the Convention on Biological Diversity which was held at Mont-real, Canada, Jan. 29th, 2000. The adoption of the Protocol is seen as a breakthrough in that it is based on the" Precautionary Principle" despite scientific uncertainties surrounding potential risks that GMOs may inflict on human health and the environment and that it has laid the ground for introduction of specific steps to handle international trading of GMOs. In this paper, the authors would like to introduce the current status and perspective of environmental and human risk assessment of GMOs.t of GMOs.

• Molecules and Cells
• /
• 제38권3호
• /
• pp.243-250
• /
• 2015

Patterning of the polar axis during the early leaf developmental stage is established by cell-to-cell communication between the shoot apical meristem (SAM) and the leaf primordia. In a previous study, we showed that the DRL1 gene, which encodes a homolog of the Elongator-associated protein KTI12 of yeast, acts as a positive regulator of adaxial leaf patterning and shoot meristem activity. To determine the evolutionally conserved functions of DRL1, we performed a comparison of the deduced amino acid sequence of DRL1 and its yeast homolog, KTI12, and found that while overall homology was low, well-conserved domains were presented. DRL1 contained two conserved plant-specific domains. Expression of the DRL1 gene in a yeast KTI12-deficient yeast mutant suppressed the growth retardation phenotype, but did not rescue the caffeine sensitivity, indicating that the role of Arabidopsis Elongator-associated protein is partially conserved with yeast KTI12, but may have changed between yeast and plants in response to caffeine during the course of evolution. In addition, elevated expression of DRL1 gene triggered zymocin sensitivity, while overexpression of KTI12 maintained zymocin resistance, indicating that the function of Arabidopsis DRL1 may not overlap with yeast KTI12 with regards to toxin sensitivity. In this study, expression analysis showed that class-I KNOX genes were downregulated in the shoot apex, and that YAB and KAN were upregulated in leaves of the Arabidopsis drl1- 101 mutant. Our results provide insight into the communication network between the SAM and leaf primordia required for the establishment of leaf polarity by mediating histone acetylation or through other mechanisms.