• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.217-222
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• 2004

As Agrobacterium tumefaciens, which has long been used to transform plants, is known to transfer T-DNA to budding yeast, Saccharomyces cerevisiae, a variety of fungi were subjected to the A. tumefaciens-mediated transformation to improve their transformation frequency and feasibility. The A. tumefaciens-mediated transformation of chestnut blight fungus, Cryphonectria parasitica, is performed in this study as the first example of transformation of a hardwood fungal pathogen. The transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator, as a selectable marker, led to the selection of more than 1,000 stable, hygromycin B-resistant transformants per 1${\times}$10$\^$6/ conidia of C. parasitica. The putative transformants appeared to be mitotically stable. The transformation efficiency appears to depend on the bacterial strain, age of the bacteria cell culture and ratio of fungal spores to bacterial cells. PCR and Southern blot analysis indicated that the marker gene was inserted at different chromosomal sites. Moreover, three transformants out of ten showed more than two hybridizing bands, suggesting more than two copies of the inserted marker gene are not uncommon.

• Reproductive and Developmental Biology
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• 제32권3호
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• pp.205-209
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• 2008

본 연구는 돼지 $\beta$-casein 유전자 위치에서 EGFP가 발현될 수 있는 knock-in 벡터를 구축하기 위하여 실시되었다. 돼지의 $\beta$-casein 유전자를 이용하여 knock-in 벡터를 구축하기 위해 돼지의 태아 섬유아세포로부터 $\beta$-casein 유전자를 동정하였고 EGFP, SV4O polyA signal을 동정하였다. Knock-in 벡터는 5' 상동 영역 약 5 kb와 3' 상동 영역 약 2.7 kb로 구성되어있으며, positive selection marker로 $neo^{r}$ 유전자를, negative selection marker로 DT-A 유전자를 사용하였다. 구축된 knock-in 벡터로부터 EGFP의 발현을 확인하기 위하여 생쥐 유선 세포인 HC11 세포에 knock-in 벡터를 도입하였다. 그 결과 EGFP의 발현을 HC11 세포에서 확인하였다. 이와 같은 결과로서 이 block-in 벡터는 knock-in 형질전환 돼지를 생산하는데 사용될 수 있을 것으로 생각된다.

• Journal of Plant Biotechnology
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• 제34권1호
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• pp.31-36
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• 2007

Though higher plants car not metabolize D-amino acid, many prokaryotes and eukaryotes have the D-amino acid metabolism. Therefore, we transformed tobacco plants with D-amino acid oxidase (DAO), which can metabolize D-amino acid, and confirmed that transgenic tobacco plants might metabolize D-amino acid. Transgenic tobacco plants were survived a high concentration of D-serine, however non-transgenic plants were not grown on D-serine medium. From Southern and Northern blot analysis, transgenic tobacco plants selected on D-serine medium were confirmed by insert and expression of transgene. $T_{1}$ tobacco seeds derived $T_{0}$ tobacco plants selfing were grown on D-serine medium and showed normal phenotype compared to wild tobacco plants. Transgenic tobacco plants displayed the metabolic capability of D-serine. Therefore, we suggested that DAO is useful selectable marker gene for plant transformation.

• Plant Biotechnology Reports
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• 제2권1호
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• pp.47-58
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• 2008

To select agronomically useful transgenic plants, a large number of transgenic events are initially produced, gene transfer confirmed, and advanced to obtain homozygous lines for testing in field trials. Direct in planta assays for identifying the transgene carriers in the segregating progeny are based on the activity of selectable marker gene and are easy, simple and inexpensive. For this purpose, expression of bar gene as measured by tolerance to damage by glufosinate ammonium, the active ingredient in the herbicide BASTA, was investigated. Dose damage curves were generated by leaf paint tests with BASTA on four genotypes of sorghum. Transgenic plants were characterized in terms of sensitivity to the concentration of glufosinate ammonium. In transgenics, symptoms of BASTA swab tests at different growth stages and PCR analysis for cry1B were carried out and correlated. Germination tests could not be employed for large scale evaluation of transgenic progeny because of mortality of tolerant seedlings after transplantation to soil. Based on the above findings, a simple, inexpensive, time-saving, two-step scheme for effective evaluation of transgenics and their progeny containing bar gene as selection marker using BASTA swab tests is described.

• 한국육종학회지
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• 제42권5호
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• pp.507-514
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• 2010

땅콩의 delta 12 fatty acid desaturase 유전자의 염기서열에서 고 올레인산을 함유하는 F435를 선발할 수 있는 PCR 기초 분자표지마커를 제작하였다. 본 연구는 포인트 뮤테이션(point mutation)의 결과로 나타나는 고 올레인산을 SNP 마커를 이용하여 하나의 염기서열차이(아데닌 삽입)를 이용하여 판별할 수 있는 분자마커이다. 제작한 마커가 고 올레인산 관련 특이 마커인지 확인하기 위하여, 일반 땅콩 9 품종과 F435를 PCR 후 아가로스 겔 상에서 확인하여 고 올레인산 특이 분자마커임을 확인하였고, 조평 ${\times}$ F435의 $F_2$ 교배조합 41 계통을 이용하여 분리양상을 확인하였다. 그 결과 지방산 분석을 하지 않고도 고 올레인산 함유 계통을 손쉽게 선발할수 있었다. 특히, 헤테로 형질을 나타내는 계통도 선발 가능하였다. 분자마커의 결과가 지방산 수준에서 일치하는지 확인하기 위해 NIR 및 가스크로마토그래피 분석결과를 알아보았데 고 올레인산 관련 분자표지마커가 NIR 및 가스크로마토그래피 분석결과와 일치하였다. 고 올레인산 땅콩의 유전적 차이를 이용하여 분자표지마커를 개발 함으로서 고 올레인산 땅콩의 정확한 선발과 품종을 개발하는데 있어서 세대단축의 효과를 가져올 것이다.

• 생명과학회지
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• 제11권4호
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• pp.316-320
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• 2001

Sonication tremendously improves the efficiency of Agrobacterium infection by introducing small and uniform fissures and channels throughout the targeted tissue. Using shoot tips of cotton as explants, the effect of sonication treatment and virulence genes in Agrobacterium tumefaciens on transformation efficiency was investigated. The pat gene which encodes resistance to the herbicide, glufosinate, was used as a selectable marker. Transformation efficiency was evaluated on th basis of survival rates of cocultivated shoot tips on selection medium containing 2.5 mg/l gulfosinate-ammonium(ppt) adn 25. mg/l Clavamax. Sonication from 5 to 15 second has a positive effect on shoop tip survival. However, whil virE as well as virG or vir GN54D showed an enhancement in transformation efficiency, virE,. virG resulted in the most significant enhancement. Overall, the combination of additional virG/virE gene and sonication treatment resulted in the most significant increase in transformation efficiency.

• 식물조직배양학회지
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• 제24권4호
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• pp.225-231
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• 1997

For genetic engineering to be commercially viable, an efficient transformation system is needed to produce transgenic plane from diverse genotypes ("generalized protocol"). Development of such a system requires optimization of a number of components such as gene transfer agent, plant tissues competent for both regeneration and transformation, and control of transgene expression. Although several novel gene transfer methods have been developed for plane, a majority of stably transformed plane express the introduced genes at low levels. Moreover, silencing of selectable marker genes shortly after their incorporation into plant chromosomes may result in low recovery of transgenic tissues from selection. Matrix attachment regions (MARs) are DNA sequences that bind to the cell's proteinaceous nuclear matrix to form DNA loop domains. MARs have been shown to increase transgene expression in tobacco cells, and reduce position in mature transgenic plants. Flanking an antibiotic resistance transgene with MARs should therefore lead to improved rates of transformation in a diversity of species, and may permit recalcitrant species and genotypes to be successfully transformed. Literature review and recent data from my laboratory suggest that MARs can serve as a transformation booster in recalcitrant plant species.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권2호
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• pp.155-160
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• 2001

We have generated a novel baculovirus genome which can be maintained in Escherichia coli that facilitates the rapid and efficient generation of recombinant baculovirus expression vectors. To make $Occ^{+}$ recombinant expression vectors, polyhedrin gene under the control of p10 promoter was inserted to bAcGOZA and this genome was designated bApGOZA. As in bAcGOZA, bApGOZA lacks a portion of the essential ORF1629 gene, but includes a mini-F replicon and selectable kanamycin-resistance marker, This occasion-producing activity of bApGOZA can be used very conveniently for its oral infectivity to insect larvae in mass production of foreign protein and insecticides.

• Mycobiology
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• 제29권3호
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• pp.132-134
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• 2001

Since it is known that Agrobacterium tumefaciens, which has long been used to transform plants, can transfer the T-DNA to yeast Saccharomyces cerevisiae during tumourigenesis, a variety of fungi were subjected to transformation to improve their transformation frequency. In this study, I report the A. tumefaciens-mediated transformation of filamentous fungus Aspergillus niger. Transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator as a selectable marker, led to the selection of $50{\sim}100$ hygromycin B-resistant transformants per $1{\times}10^7$ conidia of A. niger. This efficiency is improved $10{\sim}20$ fold more than reported elsewhere. In order to avoid the difficulties in selection transformant from the over-growing non-transformant, I used top agar containing 900 ${\mu}g/ml$ of hygromycin. Genomic PCR and Southern analysis showed that all transformants contained single T-DNA insert per fungal genome. This technique offers an easier and more efficient method than that of using protoplast.

• 한국미생물·생명공학회지
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• 제15권5호
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• pp.319-327
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• 1987

알코올 생산성이 높은 Zymomonas 균주의 기질 이용성을 넓히기 위한 목적으로 natural replicon을 포함하며 적당한 항생제 저항표지를 갖는 plasmid vector의 제조를 시도하였다. Z. mobilis ATCC10988에서 분리된 몇 개의 plasmid중 3.9kb의 적당한 크기를 갖는 pZM3를 선정하여 수종의 제한효소로 처리하여 절편의 크기에 따라 유전자 지도를 작성하였다. pZM 3의 replicon과 pBR 325의 chloramphenicol 저항유전자를 포함한 재조합 plasmid인 pHZ22를 개발하고 이 plasmid vector가 숙주세포인 Z. mobilis ATCC31821에서 독립적으로 replication됨을 확인하였다. 또 하나의 항생제 저항표지로서 RP4의 tetracycline 저항유전자를 분리하여 pHZ22에 도입함으로써 pHZT224를 제조하였는데 이 plasmid vector도 Zymomonas로 conjugation에 의해 전이되어 안정하게 유지 되었다. 본 연구를 통하여 개발된 plasmid vector는 Z. mobilis와 E. coli에 공히 작용하는 shuttle vector 로서 외부 유전자를 Zymomonas에 도입시킬 수 있는 유용한 유전자 운반체임이 확인되었다.