• Journal of Plant Biology
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• 제22권4호
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• pp.95-100
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• 1979

As a part of the studies on the regulatory mechanism of gene expression by $GA_{3}$ , the effects of $GA_{3}$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated. 1. The optimum concentration of $GA_{3}$ for the stimulation of the protein biosynthesis was 0.3mM. 2. The protein biosynthesis was remarkably increase by $GA_{3}$ during the germination. The reason for the decrease in the protein biosynthesis by 48hrs. after germination seems to be a staggered gene expression, and/or increases in protease and RNase activities. 3. The ratio of the amount of the newly synthesized protein in germinating seeds treated with $GA_{3}$ to the amount of proteins secreted into the endosperm was similar to that ratio in control. According to this result, it seems that $GA_{3}$ stimulates only the expression of certain definite genes. 4. By the treatment with $GA_{3}$, the rates of biosynthesis and phosphorylation of proteins were increased up to about 1.5 times during germination and 6 times by 72hrs. after germination, respectively. The ratio of the total soluble proteins to the phosphorpoteins considerably increased in the early germination stage (24hrs.) but decreased after 24hrs. According to the above mentioned results, the stimulation of the phosphorylation of proteins of $GA_{3}$ seems to be attributed to the increases in the activities of protein kinases.

• 한국잡초학회지
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• 제17권2호
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• pp.207-213
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• 1997

단일식물인 수수의 개화에 지베렐린이 관여하는지를 조사하기 위하여 지베렐린 생합성 억제제인 ancymidol을 처리한후 내생 지베렐린의 함량과 개화 및 생육에 미치는 영향을 조사한 결과는 다음과 같다. 1. 지베렐린 생합성 억제제 ancymidol은 공시한 두 품종 모두의 생육을 억제함과 동시에 개화를 지연시켰다. 2. $GA_3$를 Ancymidol과 동시에 처리할 경우 생육억제와 개화지연이 모두 회복되어 지베렐린이 수수의 개화에 관여함을 보였다. 3. Ancymidol 10ppm은 수수의 모든 지베렐린 ($GA_{12}$, $GA_{53}$, $GA_{44}$, $GA_{19}$, $GA_{20}$, $GA_1$ 합성을 현저히 억제하였다.

• Journal of Plant Biology
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• 제26권1호
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• pp.1-6
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• 1983

In order to investigate the effects of GA3 on RNA biosynthesis, the amounts of rRNA and tRNA in germinating maize seeds were measured. The amount of rRNA in the endospermless seedlings was remarkably increased by GA3 tretment after 48 h of germination, but no effect was observed after 12 h of germination. While the amout of rRNA in 0.5 cm shoots in length was decreased by GA3 treatment, both of the amounts of rRNA and tRNA were increased in 1~1.5 cm shoots. According to the above mentioned results, it may be suggested that RNA biosynthesis is affected by GA3 treatment, and that GA3 participates in the biosynthesis of rRNA rather than tRNA in germinating maize seeds.

• Journal of Plant Biology
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• 제25권1호
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• pp.3-8
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• 1982

As a part of the studies on the regulatory mechanism of gene expression by gibbrellic acid, the effects of $GA_3$ on the protein biosynthesis and phosphorylation in maize seedlings were investigated in the presence of actinomycin D. The activities of protein biosynthesis and phosphorylation in germinating seeds treated with $GA_3$ were greater than those of the control at the 3-day point after germination. It is assumed that the enhancement of protein biosynthesis by $GA_3$ in the presence of actinomycin D is due to the effects of $GA_3$ on the translational processes in which protein is produced from the mRNA synthesized previously.

• 한국육종학회지
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• 제43권1호
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• pp.1-13
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• 2011

Low temperature stress is one of the major negative factors affecting vegetative and reproductive growth of rice. To better understand responses of rice plants to low temperature we analyzed transcriptome expression patterns in glumous flower of cold-tolerant japonica rice variety, Stejaree45, and cold-susceptible variety, HR19621-AC6 at booting stage under cold water irrigation. A total of 2,411 probes were differentially expressed by low temperature in glumous flowers of the two varieties. Some important genes involved in hormone biosynthesis showed variety-specific regulation. Expression of GA20ox3 and GA2ox, among the genes involved in GA biosynthesis, was regulated differentially in the two varieties. Among the genes involved in IAA biosynthesis, YUCCA1 and TAA1:1 showed variety-specific regulation. Among the genes involved in cytokinin biosynthsis and signaling, expression of LOG, HK1 and HK3 was significantly down-regulated only in the cold-susceptible variety. Among the genes involved in ABA biosynthesis, NSY and AAO3 were down-regulated only in the cold-tolerant variety. In general, genes involved in GA, IAA and cytokinin biosynthesis responded to cold temperature in such a way that capacity of those bioactive hormones is maintained at relatively higher levels under cold temperature in the cold-tolerant variety, which can help minimize cold stress imposed to developing reproductive organs in the cold-tolerant variety.

• 한국식품영양과학회지
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• 제17권2호
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• pp.115-124
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• 1988

비타민C의 급원식품인 콩나물의 생장과 비타민C의 함량을 식물 생장조절제에 의하여 조절할 목적으로 gibberellic acid$(GA_3)$, indole-3-acetic acid(IAA) 및 1-naphthaleneacetic acid(NAa)의 단독 및 혼합 처리를 하였을때 가장 적당한 식물 생장조절제의 종류 및 그 농도를 찾고 이 생장조절제가 비타민C의 생합성에 미치는 영향 및 당대사와 비타민C 생성과의 관계를 검토한 결과를 요약하면 다음과 같다. 콩나물의 생장은 NAA는 $10^{-8}M$, IAA 는 $10^{-6}M$, $GA_3$는 $10^{-5}M$에서 각각 가장 양호하였다. $GA_3$와 NAA 혼합처리의 경우는 $GA_3\;10^{-5}M+NAA\;10^{-9}M$에서, $GA_3$와 IAA 혼합처리의 경우는 $GA_3,\;10^{-5}M+IAA\;$10^{-9}M$에서 양호하였고, 단독처리가 혼합처리에 비하여 양호하였으며 특히 IAA $10^{-6}M$ 처리에서 가장 좋았다. 생장이 비교적 양호한 NAA $10^{-8}M, IAA\;10^{-6}M,\;GA_3\;10^{-5}M,\;GA_3\;10^{-8}M+IAA\;10^{-6}M$ 및 $GA_3\;10^{-5}M+IAA\;10^{-9}M$의 각 처리구에서 비타민C의 생성 정도를 조사한 결과 콩나물 생장이 가장 양호하였던 IAA $10^{-6}M$ 에서 24.26mg%로서 그 함량이 가장 높았으며 대조구의 1.6배였다. 생장이 저해되지 않는 농도의 chloramphenicol(CAP) 처리에 의하여 ribulose diphosphate carboxylase(RuDpCO)는 저해되었으나 nicotineamide adenine dinucleotide phosphate-glyceraldhyde-3-phosphate dehydrogenase (NADP-GDH), galactonolactone dehydrogenase (GLD)의 활성 및 비타민C 함량은 저해되지 않았다. 따라서 비타민C의 생합성은 chloroplast RNA의 작용과는 직접적인 관련은 없고 cytoplasm과 밀접한 관련이 있다고 생각되었다. $IAA\;10^{-6}M$ 처리에 의하여 GLD 활성은 대조구의 1.8배로 촉진되었다. IAA $10^{-6}M$은 chloroplast와 cytoplasm RNA와 단백질의 생합성을 크게 촉진하였으며 cytoplasm에서 더욱 활발하였다. 따라서 IAA는 cytoplasm RNA를 조절하므로 여기서 지배되는 GLD의 생합성을 촉진시킨 결과 비타민C의 생합성이 증가된 것으로 생각되었다. 산화적 인산화 반응의 짝풀림 물질이 2,4+dinitrophenol 처리로 비타민C의 생합성은 저해되지 않았으나, 해당 저해제인 monoiodoacetate와 NaF 및 TCA 회로 저해제인 $NaN_3$와 KCN은 다같이 콩나물의 생장과 비타민C의 생합성을 크게 저해하였다

• Journal of Plant Biology
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• 제35권4호
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• pp.371-383
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• 1992

Chlorella ellipsoidea에서 분리한 엽록체의 인지질 생합성과 그의 지방산 조성에 미치는 $10^{-3}M$의 IAA(indole acetic acid)와 $2{\times}10^{-8}M의\;GA_3의$ 효과를 분석하였다. 처리구가 대조구에 비하여 생장률, 총 지질, 인지질 함량이 높은 것으로 나타났으며 특히 $GA_3$ 처리구에서는 phosphatidyl-choline 함량이 높은 것으로 분석되었다. Whole cell system에서의 주요 지방산은 대조구에서는 palmitic acid가 27.43% 였으며 IAA 처리구에서는 linolenic acid가 20.25%로 분석되었다. $GA_3$ 처리구에서는 linolenic acid가 23.17%로 인지질 형성에 이용된 주요 지방산인 것으로 분석되었다. 분리한 엽록체에서는 대조구의 주요 지방산은 palmitic acid가 35.67%로 나타났으며 IAA 처리구에서는 linolenic acid가 24.91%, GA3 처리구에서는 linolenic acid가 22.80%로 인지질 형성에 이용된 주요 지방산으로 분석되었다.

• 원예과학기술지
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• 제29권3호
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• pp.165-171
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• 2011

식물생장억제물질의 처리는 날개하늘나리의 줄기 신장을 억제시키는데, 여기에 관여하는 식물호르몬을 찾기 위해 diniconazole의 엽면살포 후 내생 GA 및 ABA의 함량 변화를 조사하였다. 그 결과, 날개하늘나리(L. dauricum)는 $GA_1$을 활성형으로 하는 early C-13 hydroxylation($GA_{19}{\rightarrow}GA_{20}{\rightarrow}GA_1$) 경로와 $GA_4$를 활성형으로 하는 non C-13 hydroxylation(NCH, $GA_{12}{\rightarrow}GA_{24}{\rightarrow}GA_9{\rightarrow}GA_4$) 경로 모두를 가지고 있었으나, 주된 경로는 NCH 경로였다. NCH 경로의 GA 생합성은 diniconazole $50mg{\cdot}L^{-1}$ 살포에 의해 초기 단계에서부터 억제되었다. 즉 diniconazole 처리구의 $GA_{12}$ 함량은 대조구에 비해 1/17로 현저히 감소되었으며, 이러한 경향은 $GA_4$까지 계속되었다. 즉 건물 1g당 $GA_{12}$ 함량은 대조구가 213.8ng인 것에 비해, diniconazole 처리구는 12.7ng이었다. ABA의 함량도 GA에서와 같이 diniconazole 살포에 의해 1/3 수준으로 크게 감소되었다. 즉 건물 1g당 ABA 함량은 대조구 37.2ng인 것에 비해, diniconazole 처리구는 14.8ng이었다. 본 연구의 결과, 내생 $GA_4$, $GA_1$, 그리고 ABA의 함량을 고려할 때 diniconazole에 의한 날개하늘나리의 초장감소는 $GA_4$의 생합성 억제에 기인한 것으로 생각된다.

• 방사선산업학회지
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• 제6권3호
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• pp.281-287
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• 2012

The model plant, Arabidopsis thaliana is the subject of an international genome research project. Massive doses of ionizing radiation have been shown to induce physiological changes in plants. The wild-type (Ler) Arabidopsis plants were irradiated with 100 Gy and 800 Gy of gamma-ray. Gibberellin (GA) affects developmental processes and responses according to the various environment conditions in diverse plant. The 13 GA isomers were analyzed at vegetative (VE) and reproductive (RE) stages by HPLC. Total GA contents were reduced with the increase in radiation doses at VE and RE stages. Specifically, levels of GA3, GA4, GA12, and GA34 were significantly reduced with the increase of radiation doses. Oligonucleotide microarrays analysis was performed with Arabidopsis plants at different developmental stages and doses of gamma-ray. Through the microarray data, we isolated 41 genes related to GA biosynthesis and signaling transduction. Expression of these genes was also decreased as the reduction of GA contents. Interestingly, in GA signaling related gene expression, gibberellin-responsive protein, putative (At2g18420) was down-regulated at VE and RE stages. Myb21 (At3g27810), Myb24 (At5g40350), and Myb57 (At3g01530) was down-regulated at RE stage. In GA biosynthesis related gene expression, YAP169 (At5g07200) and GA20ox2 (At5g51810) were down-regulated at 100 Gy treatment of VE stage and 800 Gy treatment of RE stage in cytoplasm, respectively. However, exceptively, GA3ox2 (At1g80340) was up-regulated at 100 Gy treatment of RE stage in cytoplasm. In this study, the wild type (Ler) Arabidopsis plants showed differences in response with development stage at the various doses of gamma-rays. GA contents change was reported in gamma irradiated plant.

• Journal of Plant Biotechnology
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• 제48권3호
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• pp.186-192
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• 2021

The roots of Korean ginseng (Panax ginseng) have a long history of usage as a medicinal drug. Ginsenosides, a group of triterpenioid saponins in ginseng, have been reported to show important pharmacological effects. Many studies have attempted to identify the ginsenoside synthesis pathways of P. ginseng and to increase crop productivity. Recent studies have shown that exogenous gibberellin (GA) treatments promote storage root secondary growth by integration of the modulating cambium stem cell homeostasis with a secondary cell wall-related gene network. However, the dynamic regulation of ginsenoside synthesis-related genes and their contents by external signaling cues has been rarely evaluated. In this study, we confirmed that GA treatment not only enhanced the secondary growth of P. ginseng storage roots, but also significantly enriched the terpenoid biosynthesis process in RNA-seq analysis. Consistently, we also found that the expression of most genes involved in the ginsenoside synthesis pathways, including those encoding methylerythritol-4-phosphate (MEP) and mevalonate (MVA), and the saponin content in both leaves and roots was increased by exogenous GA application. These results can be used in future development of biotechnology for ginseng breeding and enhancement of saponin content.