• Journal of Plant Biotechnology
• /
• 제31권4호
• /
• pp.255-259
• /
• 2004

Agrobacterium과 자엽절 공동배양으로 대두 형질전환체를 생산하였다. 대두 배양재료는 3개의 품종과 1개의 genotype의 자엽절 절편을 사용하였으며, bar유전자와 GUS유전자로 제작된 pPTN289와 pCAMBIA3301벡터를 LBA4401, GV3101, EHA101, C58에 각각 형질전환하여 공동 배양하였고 모든 형질전환 방법은 약간 변형된 Zhang 등(1999)의 방법에 따라 수행하였다. 형질전환빈도는 아그로박테리움의 종류에 따라 현저한 차이가 있었으며, 특히 사용한 균주중 EHA101에서 3.6%로 최대치를 보였다. Glufosinate가 첨가된 선발배지에서 106개의 식물체를 얻었으며, 이중 Thorne에서 5개체, 1049에서 5개체, 백운콩에서 1개체 등 모두 11개로부터 GUS양성반응을 확인하였다. Southern분석과 basta검정법에 의하여 T1세대 식물체로부터 GUS유전자와 bar유전자가 발현되고 있음을 확인하였다.

• Journal of Plant Biotechnology
• /
• 제2권1호
• /
• pp.35-41
• /
• 2000

Transgenic cabbage (Brassica oleracea ssp. capitata) plants resistant to the commercial herbicide Bast $a^{R}$ were obtained by Agrobacterium tumefaciens - mediated transformation. Hypocotyl segments of in vitro grown plants were infected with Agrobacterium tumefaciens LBA 4404 harboring plasmid pMOG6-Bar which contains hpt and bar genes. Explants were cultured on callus induction medium (MS basal medium + 1 mg/L NAA + 2 mg/L BA + 2 mg/L AgN $O_3$+ 100 mg/L carbenicillin + 250 mg/L cefotaxime) supplemented with 15 mg/L hygromycin. Hygromycin resistant calluses were transferred to shoot regeneration medium (MS basal medium + 0.1 mg/L NAA + 2 mg/L BA + 3% sucrose + 2 mg/L AgN $O_3$+ 15 mg/L hygromycin + 250 mg/L cefotaxime + 100 mg/L carbenicillin). In order to induce roots, elongated shoots were placed on the MS medium without plant growth regulators and hygromycin. Southern blot analysis of several putative transgenic plants indicated that one to five intact copies of Apt and bar genes were incorporated into the genome. Expression of bar gene was confirmed by Northern blot analysis and by herbicide resistant phenotype. Seed progeny from self-pollinated transformants expressed the herbicide resistance and showed Mendelian segregation of the introduced gene.e.

• Journal of Ginseng Research
• /
• 제27권1호
• /
• pp.17-23
• /
• 2003

Agrobacterium-mediated transformation of American ginseng (Panax quinquefolius L.) with strain LBA 4404 containing a rice thaumatin-like protein gene is described. The selectable markers used were phosphinothricin acetyltransferase and hygromycin phosphotransferase genes. Epicotyl explants from seedlings were precultured for 5-7 days on Murashige and Skoog medium with ${\alpha}$-naphthaleneacetic acid and 2,4 dichlorophenoxyacetic acid at 10 ${\mu}$M and 9 ${\mu}$M, respectively (ND medium), prior to Agrobacterium infection. The explants were immersed in a bacterial suspension for 20 min. A post-infection co-culture period of 3-4 days was provided on ND medium. Selection for transformed calli was conducted on ND medium with 20 mg/L phosphinothricin followed by 100 mg/L hygromycin over an 8-month period. it transformation frequency of 24.8% was achieved at the callusing phase. The presence of the transgenes in calli was confirmed by Southern hybridization and polymerase chain reaction analysis. The expression of the thaumatin-like protein gene in ginseng calli was demonstrated by Western blot analysis. Somatic embryos were produced from both transgenic calli and suspension cultures, and plantlets were recovered that expressed the transgenic thaumatin-like protein gene.

• 원예과학기술지
• /
• 제29권5호
• /
• pp.467-473
• /
• 2011

Flavonoid are large group of the polyphenolic compounds which are distinguished by an aromatic or phenolic ring structure and the phenolic compounds are induced by microbial infection, ultraviolet radiation, temperature and chemical stress. They are known for their antioxidant activity, anti-allergic, anti-inflammatory, anti-microbial and anti-cancer activities. In this study, changes in flavonoid content were investigated using heterologous chalcone isomerase (CHI) expression system. Also, phenolic compounds level was measured to examine the relation between flavonoids and phenols contents. Explants of lettuce (Lactuca sativa L.) were transformed with Agrobacterium tumefaciens LBA 4404 strain containing pFLH-CHI (derived from pPZP2Ha3) vector constructed with CHI gene from Brassica rapa. The putative transgenic plants were confirmed by genomic DNA PCR analysis. Also the transcription levels of the gene were analyzed by semi-quantitative RT-PCR with gene specific primers. The total flavonoid contents were increased at $T_0$ and $T_1$ generations over 1.4 and 4.0 fold, respectively. Total phenol contents also increased at $T_1$ generation. These results indicate that CHI gene plays an important role to regulate the accumulation of flavonoids and its component changes.

• Journal of Plant Biotechnology
• /
• 제3권3호
• /
• pp.135-140
• /
• 2001

An Agrobacterium tumefaciens LBA4404 (harboring antisense OMT gene)-mediated transformation method has been developed for poplar (P.nigra x maximowiczii) using prolonging co-cultivation time. Explants on LT (longterm) were induced transgenic calli one month earlier than those from ST (short-term) co-cultivation and remained healthier on LT than ST. With this approach, LT method reduced time to produce transgenic calli. Shoots were successfully regenerated from transgenic calli on SIM (Shoot Induction Medium) and rooted well on the basal medium spontaneously. The presence of antisense OMT gene was verified both by PCR and Southern analysis. Each transgenic poplar was phenotypically indishtinguishable when compared with controls for their growth pattern, leaf morphologies and xylem coloration.

• 한국작물학회지
• /
• 제46권5호
• /
• pp.375-379
• /
• 2001

Transgenic plants from hypocotyl segments of buckwheat were produced with the Agrobacterium strain LBA4404 harboring the binary vector pBI121 containing chimeric genes of neomycin phosphotransferase II (npt II) and $\beta$-glucuronidase (gus). Two weeks after co-cultivation with Agrobacterium, most of the hypocotyl segments gradually became brown and died on the selection medium containing 100mg/$\ell$ of kanamycin. Plants regenerated from the hypocotyl explants grown on selection medium were GUS-positive in the leaf, stem and vascular tissues by histochemical assay, and varied in gus activity (440-2568 pmol, 4-MU/mg protein) by fluorimetry. The plants showing GUS activity were confirmed of containing GUS and NPT-II genes by polymerase chain reaction (PCR). Within 3 months, transgenic buckwheat plants were able to obtained from the hypocotyl segments.

• 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 Biotechnology
• /
• 제36권4호
• /
• pp.366-372
• /
• 2009

This study was conducted to develop new lines expressing the characteristic of early flowering by introducing MdMADS2 gene in chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura) ‘Zinba'. Transformation of chrysanthemum was conducted by Agrobacterium tumefaciens LBA4404 harboring the binary vector containing MdMADS2 controlled by double CaMV 35S promoters. Ninety three shoots were regenerated from 1,463 leaf segment explants cultured on the first selection medium (MS basal salts + 1.0 mg/L BA + 0.5 mg/L IAA + 10 mg/L kanamycin + 400 mg/L cefotaxime, pH 5.8) after co-cultivation, and 20 out of the 93 shoots rooted on the second selection medium containing 20 mg/L kanamycin and 400 mg/L cefotaxime. Many escapes (98.6%) were removed on the selection stage for rooting. Nineteen lines were confirmed as transgenic plant with transgene by PCR analysis. Six transgenic plants flowered 2-11 days earlier than non-transgenic plant without big change of phenotype, and especially, 3 (Mo-7, Mo-11, Mo-17) out of 6 transgenic lines showed a significant reduction in days to flowering compared to non-transgenic plant. Introduction and expression of MdMADS2 gene in them were confirmed by Southern and real-time PCR analyses, respectively.

• 한국초지조사료학회지
• /
• 제18권1호
• /
• pp.69-76
• /
• 1998

This study was conducted to construct of the transgenic plants wliich are resistant to oxidative stresses including ozone with B. mpestris cytosolic glutathione reductase cDNA using the binary vector system of Agrobacterium tumefaciens. The 1.8kb B. campestris cytosolic GR cDNA was subcloned into the unique Sma I site of the plant transformation vector pBKSI- I, downstream of the constitutive CaMV 35s promoter and upstream of the nos termination sequence, in place of the uidA (GUS) reporter gene. The resulting plant transformation vector, pBKS-GRI, was introduced into A. tumefaciens LBA4404 by two cycles of tkeze-thaw method. The B. nqus cotyledonary petioles were transformed by the Agrubaferium harboring pBKS-GRI. Transformed shoots were induced and selected on regeneration medium supplemented with kanarnycin. The shoot formation was increased remarkably by addition of Ag$NO_3$, in MS media. The transgenic plants were analyzed for the presence of the B. campestris GR gene by Southern blot analysis and it was confirmed that a foregin gene was stably integrated into the genomes of B. nqus plants.

• Plant Resources
• /
• 제6권2호
• /
• pp.108-113
• /
• 2003

This study was carried out to obtain basic information for possibility of oral vaccine in carrot using Agrobacteruim -mediated transformation system. The epitope region of porcine epidemic diarrhea virus (PEDV) spike gene which is classified as a member of the Coronaviridae and causes an acute enteritis in pigs was successfully expressed in carrot (Daucus carota) using the Agrobacterium-mediated transformation system. Hypocotyl segments of in vitro germinated plantlets were infected with Agrobacteriun tumefaciens LBA 4404 harboring PEDV spike gene. Embryogenic callus (EC) was induced on MS selection medium with 1 mg/L 2,4-D, 50 mg/L kanamycin and 300 mg/L cefotaxime after 45 days of culture. Subcultured ECs on MS selection medium without 2,4-D were converted to somatic embryos (SE) of various stage; globular, heart and torpedo stage. Putative transgenic embryos were selected on MS medium with 50 mg/L kanamycin and 300 mg/L cefotaxime. Regenerated plantlets from transformed SE were induced on MS medium containing 50 mg/L kanamycin after 30 days of culture. Genomic PCR confirmed the integration of PEDV spike gene into nuclear genome of carrot and northern blot analysis demonstrated the expression of PEDV spike gene in transgenic carrot.