• Applied Biological Chemistry
• /
• 제45권4호
• /
• pp.203-206
• /
• 2002

${\gamma}-Tocopherol$ methyltransferase(TMT)는 토코페롤 생합성 대사의 마지막 단계인 감마 토코페롤을 알파 토코페롤로 변환하는데 관여하는 효소이다. 들깨의 미성숙 종자 cDNA유전자 은행에서 TMT로 추정되는 유전자를 분리하였으며 이 유전자는 1369개의 염기와 367개의 아미노산으로 구성되었으며 분자량은 약 42kDa의 추정된다. 이 cDNA는 Genbank와 상동성 분석결과 애기장대의 TMT유전자와 아미노산 수준에서 60% 정도의 상동성을 가지고 있으며 methyltransferase domain과 S-adenosyl methionine binding domain을 가지고 있으므로 TMT 유전자로 추정했다. 이 유전자의 특성을 알기 위하여 완전한 크기를 가지는 TMT유전자를 대장균에서 발현하고 invitro에서 효소의 활성을 측정하였다.

• 식물조직배양학회지
• /
• 제27권6호
• /
• pp.435-439
• /
• 2000

겨울 상추 품종인 청치마 상추의 자엽조직을 ${\gamma}$-TMT유전자가 도입된 A. tumefaciens LBA 4404와 공동배양한 후, 50 mg/L kanamycin, 500 mg/L carbenicillin, 0.1 mg/L NAA, 0.5mg/L BA가 첨가된 MS재분화 배지에 옮겨 약4주 배양하여 재분화된 신초를 얻었다. 재분화된 신초를 50 mg/L kanamycin, 250mg/L carbenicillin이 포함된 MS 기본 배지에 옮겨 발근된 소식물체를 얻었다. 선발된 형질전환 식물체의 genomic DNA에 대한 PCR분석과 Southern분석을 수행하여 애기장대 ${\gamma}$-TMT유전자 특이적 DNA단편이 상추의 genomic DNA내에 삽입되었음을 확인하였다. 선발된 상추 형질전환체 잎의 $\alpha$-tocopherol/${\gamma}$-tocopherol 함량 비율이 대조 식물체에 비하여 약 4배 증가하여 도입된 ${\gamma}$-TMT유전자가 안정적으로 발현함을 나타내었다.

• Molecules and Cells
• /
• 제19권1호
• /
• pp.16-22
• /
• 2005

A cDNA encoding ${\gamma}-tocopherol$ methyltransferase (${\gamma}-TMT$) from Arabidopsis thaliana was overexpressed in lettuce (Latuca sativa L.) to improve the tocopherol composition. Seven lines of lettuce ($T_0$) containing the ${\gamma}-TMT$ transgene were produced by Agrobacterium-mediated transformation. The inheritance and expression of the transgene were confirmed by DNA and RNA gel blot analyses as well as quantification of tocopherols and ${\gamma}-TMT$ activities. The ratio of ${\alpha}-/{\gamma}-tocopherol$ content (TR) varied from 0.6 to 1.2 in non-transformed plants, while the $T_0$ plants had ratios of 0.8 to 320. The ratio ranged from 0.4 to 544 in 41 $T_1$ progenies of the $T_0$ transgenic line gTM3, and the phenotypic segregation indicated monogenic inheritance of the transgene (i.e., 3:1 = dominant:wild-type classes). There was a tight relationship between the TR phenotype and ${\gamma}-TMT$ activity, and enzyme activities were affected by the copy number and transcript levels of the transgene. The TR phenotype was stably expressed in $T_2$ progenies of $T_1$ plants. The results from this study indicated that a stable inheritance and expression of Arabidopsis ${\gamma}-TMT$ transgene in lettuce results in a higher enzyme activity and the conversion of the ${\gamma}-tocopherol$ pool to ${\alpha}-tocopherol$ in transgenic lettuce.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2000년도 춘계 학술대회지
• /
• pp.420-421
• /
• 2000

• Journal of Plant Biotechnology
• /
• 제35권4호
• /
• pp.329-335
• /
• 2008

Tocopherols are essential lipophilic antioxidant in human cells, while little is known about its function in plant tissues. To study the impact of composition and content of tocopherols on stress tolerance, tobacco (Nicotiana tabacum) was transformed with a construct containing a cDNA insert encoding $\gamma$-tocopherol methyltransferase ($\gamma$-TMT/VTE4) from perilla under the control of the cauliflower mosaic virus (CaMV) 35S promoter. The transgenic tobacco was confirmed by PCR and RT-PCR. The total content and composition of tocopherols in the transgenic lines were similar with wild type controls. However, chlorophyll-a and carotenoid content in the transgenic lines were increased by up to 45% (P<0.01) and 39% (P<0.02), respectively. Also, the over-expression of $\gamma$-TMT increased the salt stress tolerance in tobacco plants. These results demonstrate that over-expression of $\gamma$-TMT gene in tocopherol bio-synthetic pathway can increase salt stress tolerance and contents of chlorophyll-a and carotenoid in transgenic tobacco plants.

• Journal of Plant Biotechnology
• /
• 제7권3호
• /
• pp.203-209
• /
• 2005

This study was conducted to improve tocopherol (vitamin E) composition in soybean (Glycine max) by introducing a gamma-tocopherol methyl transferase (${\gamma}$-TMT) gene via Agrobacterium tumefaciens-mediated transformation. Immature cotyledon explants were cocultivated with Agrobacterium tumefaciens. Putative transgenic embryos were selected from immature cotyledons on MS medium supplemented with 40 mg/L 2,4-D containing 100 mg/L kanamycin, 500 mg/L carbenicillin and 250 mg/L cefotaxime. Plantlets were developed from somatic embryos, and then transferred to soil. Nineteen regenerated plantlets obtained on the selection medium from 1,460 cotyledons. However, only 9 plantlets were confirmed as transformed plants. Integration of the transgene into the soybean genomic DNA was confirmed by PCR and Southern blot analysis. HPLC analysis showed that the content of ${\alpha}$-tocopherol in transgenic soybean seeds (AT-1) was approximately 4-fold higher than that of non-transgenic plants. Conclusively, we obtained the transgenic soybean having increased ${\alpha}$-tocopherol content by the overexpression of ${\gamma}$-TMT transgene.

• 한국약용작물학회지
• /
• 제15권5호
• /
• pp.339-345
• /
• 2007

Field performance and morphological characterization was conducted on seven transgenic lines of Codonopsis lanceolata expressing ${\gamma}-TMT$ gene. The shoots were obtained from leaf explants after co-cultivation with Agrobacterium tume-faciens strain LBA 4404 harboring a binary vector pYBI 121 that carried genes encoding ${\gamma}-Tocopherol$ methyltransferase gene (${\gamma}-TMT$) and a neomycin phosphotransferase II gene (npt II) for kanamycin resistance. The transgenic plants were transferred to a green house for acclimation. Integration of T-DNA into the $T_0\;and\;T_1$ generation of transgenic Codonopsis lanceolata genome was confirmed by the polymerase chain reaction and southern blot analysis. The progenies of transgenic plants showed phenotypic differences within the different lines and with relative to control plants. When grown in field, the transgenic plants in general exhibited increased fertility, significant improvement in the shoot weight, root weight, shoot height and rachis length with relation to the control plants. However, all seven independently derived transgenic lines produced normal flower with respect to its shape, size, color and seeds number at its maturity. Indicating that the addition of a selectable marker gene in the plant genome does not effect on seed germination and agronomic performance of transgenic Codonopsis lanceolata. $T_1$ progenies of these plants were obtained and evaluated together with control plant in a field experiment. Overall, the agronomic performance of $T_1$ progenies of transgenic Codonopsis lanceolata showed superior to that of the seed derived non-transgenic plant. In this study, we report on the morphological variation and agronomic performance of transgenic Codonopsis lanceolata developed by Agrobacterium transformation.

• 한국약용작물학회:학술대회논문집
• /
• 한국약용작물학회 2007년도 춘계학술발표회
• /
• pp.294-295
• /
• 2007

• 한국약용작물학회:학술대회논문집
• /
• 한국약용작물학회 2007년도 춘계학술발표회
• /
• pp.296-298
• /
• 2007

• Applied Biological Chemistry
• /
• 제49권3호
• /
• pp.192-195
• /
• 2006

국내에서 개발된 비타민 E 강화 유전자변형 들깨의 정성 PCR 분석법의 개발을 위해 들깨의 내재 유전자로써 KAS-I (Beta-ketoacyl-ACP synthase I)를 선별하였고, 이러한 내재유전자를 특이적으로 증폭시킬 수 있는Primer(Pfru3-F/R)쌍을 이용한 PCR에서 95 bp의 PCR증폭 산물을 얻었으며, 들깨를 포함한 16개 작물에 대해 PCR을 수행한 결과에서 들깨만이 특이적으로 증폭되는 것을 확인하였다. 또한, 비타민 E 강화 유전자변형 들깨에 삽입된 TMT(${\gamma}$-tocopherol methyltransferase) 유전자와 OCS(Octopine synthase) terminator 연결 부위를 증폭시켜 148 bp의 PCR 산물을 얻을 수 있는 primer(TMTO-F/R)를 제작하였으며, 이러한 두 쌍의 primer를 이용하여 국내 개발된 비타민 E 강화 유전자변형 들깨의 PCR 정성 분석법을 확립하였다.