• Journal of Plant Biotechnology
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• 제5권2호
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• pp.87-93
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• 2003

Brachiaria (Poaceae) is the most important forage genus for cattle production in Brazil. The genetic breeding of this genus is limited by the incompatibility among species, differences in ploidy level and the natural cloning of plants by apomixis (Valle and Miles 1992). However, plant regeneration via tissue culture methods and genetic engineering provide an opportunity to introduce new characteristics in plants of this genus. We have developed methods for the 'genetic modification of Brachiaria brizantha cv. Marandu via biolistic transformation. A higher number of shoots was obtained with 4 mg/L 2.4-diclorophenoxyacetic acid and 0.2 mg/L benzylaminopurine in calli induction medium and 0.1 mg/L naphtaleneacetic acid and 4.0 mg/L kinetin in shoot regeneration medium. A selection curve for mannose was determined to use phospho mannose isomerase (PMI) gene of Escherichia coli as a selection marker. Calli formation was inhibited from 5 g/L mannose, even in the presence of sucrose while calli that were formed in the presence of mannose failed to develop embryos showing that PMI gene can be used for selection of transformants of this grass. Different promoters were tested to evaluate the efficiency based on the detection of the GUS gene expression (Jefferson et al. 1987). The monocot promoters, act1-D and ubi-1, resulted in higher expression levels than dicot promoters, ubi-3 and act-2, or the CaMV35S and CVMV promoters.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1528-1531
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• 2015

Sclerotia of Wolfiporia cocos are of medicinal and culinary value. The genes and molecular mechanisms involved in W. cocos sclerotial formation are poorly investigated because of the lack of a suitable and reproducible transformation system for W. cocos. In this study, a PEG/CaCl₂-mediated genetic transformation system for W. cocos was developed. The promoter P_gpd from Ganoderma lucidum effectively drove expression of the hygromycin B phosphotransferase gene in W. cocos, and approximately 30 transformants were obtained per 10 μg DNA when the protoplast suspension density was 10⁶ protoplasts/ml. However, no transformants were obtained under the regulation of the PtrpC promoter from Aspergillus nidulans.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.379-387
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• 2010

Oilseed rape (Brassica napus L.) is an important crop due to its high oil content in the seed. Recently, the demand for the improvement of crop for biodisel energy source is increased as oil prices in the world has increased dramatically. Until now, oilseed rape breeding was carried out by cross-hybridization between different varieties and related germplasms. However, like as many other crops, the application of tissue culture and gene transformation systems has been introduced into oilseed rape breeding program including the development of transgenic canola plants. In this study, we reviewed a history of tissue culture and genetic transformation research in oilseed rape plants and indicated some important aspects for the production of transgenic oilseed rape plants.

• 대한수학교육학회지:수학교육학연구
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• 제25권4호
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• pp.499-524
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• 2015

본 연구는 GSP 환경에서 합동변환 개념에 대한 발생적 분해를 제시하고, 중학교 2학년 영재학급 학생 4명을 대상으로 참여 학생들의 합동변환 개념에 대한 발생적 분해가 어떻게 드러나고 변화하는지, 또한 드래그 활동이 합동변환 개념의 이해에 어떤 역할을 하는지 알아보고자 하였다. 합동변환 개념을 이해할 때, 학생들은 중요한 두 스키마인 '한 점 이동 스키마'와 '변환 이동 스키마'를 동시에 고려하였으며, 한 학생이 어느 한 스키마를 선호하거나 치중하여 사용하기 보다는 두 스키마를 모두 고려하되 방향을 정하기 어려운 과제일수록 '한 점 이동 스키마'에 더 의존하는 경향을 보였다. Law(1991)의 '한 점 이동 스키마'의 집약화에 따른 '도형 이동 스키마'는 학생들에게 관찰되지 않았으며, 합동변환의 합성을 완벽하게 이해하기 위해서 조정뿐만 아니라 가역적 사고가 더 필요하였다. 또한, 합동변환 개념을 이해하는 과정에서 학생의 드래그 활동은 정의역과 치역을 평면 위의 점으로 확장하는데 도움이 되었고, 벡터, 회전의 중심, 대칭축의 역할을 인식하는데 도움이 되었다.

• Journal of Plant Biotechnology
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• 제35권2호
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• pp.109-114
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• 2008

Agrobacterium 공동배양을 적용하여 소포자에 Agrobacterium-mediated genetic transformation이 가능한지를 조사하기 위하여 소포자 형질전환에 대한 조건을 구축하고자 하였다. 선발 배지에서 Kanamycin에 대한 소포자의 배발생율을 조사하였는데 Kanamycin 농도 10 mg/L, 50 mg/L, 100 mg/L를 처리하였을 때 배발생율이 각각 4배, 8배, 10배 이하로 감소하였고 Kanamycin이 형질전환 선발마커로 사용할 경우 형질 전환율이 매우 낮아질 것으로 사려 된다. GFP 유전자 발현을 이용하여 visual reporter로서 활용하고자 Agrobacterium과 공동배양 후 배발생 유도 배지에 치상하고 소포자가 배로 발생하는 과정을 현미경으로 조사하면서 GFP 발현을 관찰하였다. 소포자는 배양 12일째서부터 소포자 분열로 cluster를 형성하였으며 24일째에는 반복되는 분열을 통하여 큰 mass의 배로 발달된 모습을 각각 GFP 발현을 통해 볼 수 있었다. 배양48일째도 GFP발현이 계속 보이며 총 8 개의 배에서 GFP 발현 재현성을 보임으로서 형질전환은 된 것으로 보이지만 더 이상 성숙된 배로 자라지 않아 소포자를 이용한 Agrobacterium 형질전환 조건을 더 개선할 필요가 있다.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.453-460
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• 1993

The extracellular bacteriolytic enzyme from alkalophilic Bacillus sp. YJ-451 was endopeptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan. Protoplast transfomation system of B. subtilis by the lytic enzyme that differs, in mechanisms, from lysozyme which was used to transformation of B. subtilis was investigated. High protoplast yield was obtained from cells cultured in PAB at the late logarithmic growth phase.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.150-150
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• 2004

• Journal of Plant Biotechnology
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• 제34권1호
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• pp.37-45
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• 2007

수박은 형질전환이 매우 어렵고 직접적인 신초 유도방법으로는 안정된 형질전환을 기대할 수 없어서, 다른 여러 작물에서 높은 효율을 보였던 캘러스 유래 신초 유도 방법을 도입하고자 하였다. 수박의 최적 캘러스 유도조건은 자엽 절편체의 경우 2.0 mg/L zeatin과 0.1 mg/L IAA이었으며 뿌리 절편체의 경우 2.0 mg/L BA와 0.1 mg/L 2,4-D이었다. NptII 유전자의 선발 항생제는 kanamycin보다는 paromomycin 빠르고 효과적이었으며, 수박의 절편체에 Agrobacterium을 접종 한 후 paromomycin을 125 mg/L 첨가한 배지에서 선발하였다. pmGFP5-ER vector로 형질전환한 후 캘러스 상태에서 형광현미경을 통해 GFP 유전자의 도입을 확인하였으며, 딱딱한 초록색의 캘러스에서 강한 GFP 발현을 관찰하였고, 자엽유래 캘러스의 경우 WM8에서 9.0%, 뿌리유래 캘러스의 경우 WM6에서 8.3%의 가장 높은 GFP 발현 효율을 보였다. GFP 유전자 도입과 같은 방법으로 WMV-CP 유전자가 있는 pWMV2300 vector로 형질전환한 후 캘러스 상태에서 PCR 및 Southern blot 분석을 한 결과, 두 점의 캘러스에서 WMV-CP 유전자가 도입되었음을 확인하였다. 본 연구를 통하여 확립된 수박의 캘러스 유도 시스템은 안정된 수박 형질전환 방법에 기초 자료로서 이용될 것이다.

• Journal of Plant Biotechnology
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• 제39권1호
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• pp.1-12
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• 2012

With the increasing advances in Brassicaceae genetics and genomics, considerable progress has been made in the transformation of Brassicaceae. Transformation technologies are now being exploited routinely to determine the gene function and contribute to the development of novel enhanced crops. $Agrobacterium$-mediated transformation remains the most widely used approach for the introduction of transgenes into Brassicaceae. In $Brassica$, the transformation relies mainly on $in$ $vitro$ transformation methods. Nevertheless, despite the significant progress made towards enhancing the transformation efficiencies, some genotypes remain recalcitrant to transformation. Advances in our understanding of the genetics behind various transformations have enabled researchers to identify more readily transformable genotypes for use in routine high-throughput systems. These developments have opened up exciting new avenues to exploit model $Brassica$ genotypes as resources for understanding the gene function in complex genomes. Although many other Brassicaceae have served as model species for improving plant transformation systems, this paper summarizes on the recent technologies employed in the transformation of both $Arabidopsis$ and $Brassica$. The use of transformation technologies for the introduction of desirable traits and a comparative analysis of these as well as their future prospects are also important parts of the current research that is reviewed.

• 한국식품영양학회지
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• 제5권2호
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• pp.77-83
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• 1992

The optimum conditions and mechanisms for the plasmid-mediated genetic transformation of intact cells of Bacillus brevis Pl76-2, an extracellular protein producing bacterium by electroporation were investigated. It was found that pUB110 Plasmid DNA can be introduced into intact bacterial cells by electroporation. The frequency of transformation by this electroporation system depended upon the initial electric field strength, the capacity of the electric discharge capacitor, growth stage, number of successive pulses and composition of electroporation buffer. It was effective for transformation that cells were harvested, washed and resuspended with HSM [7M HEPES(PH 7.4), 272mM sucrose, 1 mM MgCl2] electroporation buffer when cell growth was attained to 1.2 at OD660. A maximum frequency of transformation of 2.40$\times$104 transformants per$\mu$g plasmid DNA was obtained by two succesive Pulses with an initial electric field strength of 12.5kV/cm and with a capacitance of 7.3uF.