• Korean Journal of Medicinal Crop Science
• /
• v.17 no.4
• /
• pp.286-292
• /
• 2009

The aim of this study was to investigate the effect of plant growth at several different growing periods on antioxidant activities and zeatin and ABA contents of Artemisia iwayomogi. Measurements of antioxidant activities, lipid peroxidation inhibition, and superoxide radical scavenging activity were done using PMS, NBT and lipid auto-oxidation analysis, respectively. The results show that activities of antioxidants from Artemisia iwayomogi had much higher than BHT. DPPH free radical scavenging effect of Artemisia leaf extract was increased from $71.06{\pm}4.36%$ in April to $90.06{\pm}4.41%$ in October. Activities of superoxide radical scavenging and lipid peroxidation inhibition were $33.83{\pm}3.45%$ and $45.60{\pm}3.10$ in April and then increased to $84.40{\pm}4.00%$ and $75.86{\pm}3.50%$ in October, respectively. An ELISA technique has been developed for the determination of zeatin and ABA in Artemisia leaves. By this method, the content changes of zeatin and ABA from Artemisia during the growth were investigated. The zeatin content in leaf was measured to be $186.86{\pm}1.40$ pmol/g dry weight in April, however, decreased to $117.93{\pm}5.83$ pmol in October. The ABA content in leaf increased from $19.00{\pm}1.26$ nmol in April to $68.20{\pm}2.52$ nmol in October. Relationship between antioxidant activities and plant hormone contents was indicated that antioxidant activity may depend on decreasing zeatin content or increasing ABA content.

• Journal of Bio-Environment Control
• /
• v.6 no.3
• /
• pp.143-150
• /
• 1997

In order to produce young leaf of butterbur(Petasites japoflicus MAX.) in early spring, the planting date and relationship between abscisic acid(ABA) content and dormancy were investigated. Under open field condition, the dormancy of rootstock was initiated in the beginning of October, was the deepest in the middle of November and was completely broken in the end of December. When those periods were converted by the low accumulation hour below 5$^{\circ}C$, 900 hours were required approximately. This means that the rootstock needs for dormant breaking necessitates under the low temperature. In relationship between growing period and ABA content, the ABA in root-stock did not exist during maximum growing period, from April to September. This means that the ABA together with other substances in rootstock can be transferred to the shoot part with sprouting. While shoot part withered by decreacing the open field temperature since October, the ABA intiated to exist in rootstock. This means that the ABA in the shoot part can be transferred to the rootstock part. Therefore, it was concluded that the ABA which has been known that inhibiting growth and inducing dormancy was closely related with dormancy of rootstock.

• Analytical Science and Technology
• /
• v.14 no.5
• /
• pp.458-463
• /
• 2001

The concentration of free PAs in the cells was decreased gradually from $500{\mu}mole$ to $290{\mu}mole$ for PUT, from $153{\mu}mole$ to $79{\mu}mole$ for SPD, from $69{\mu}mole$ to $20{\mu}mole$ for SPM during the ABA treatment within 1 hour, and was slightly changed with the increasing or decreasing between $290{\mu}mole{\sim}220{\mu}mole$ in the constant content level of PUT during the continuously ABA treatment of 2 days in the young cotyledons. The concentration of free PUT was gradually decreased from $160{\mu}mole$ to $9{\mu}mole$ during the ABA treatment within 1 hour like as cotyledons, and decreased from $9{\mu}mole$ to $5{\mu}mole$ during the continuously ABA treatment 2 days in the young hypocotyls. PUT and other PA were existed $5{\mu}mole$ during the continuously ABA treatment of 2 days in the hypocotyls. It showed that during the ABA treatment was decreased all PA concentration in the cells and PAs were not concerned directly to stress, but might regulated physiological change against stress.

• Journal of Bio-Environment Control
• /
• v.15 no.4
• /
• pp.417-420
• /
• 2006

To investigated the dormancy of chicory (Cichorium intybus L.) for production of high quality rootstocks, growth characteristics and abscisic acid (ABA) contents was conducted. The accumulation hours below $5^{\circ}C$ in field was increased slowly from October 7 to December 3, but there after increased largely. The rootstock weights was increased from the end of October to December 3, there after was not changed to December 3. ABA contents within the rootstock was not changed from October 7 to December 3, and there was suddenly increased for two weeks to December 24. As results of the sudden changed date of accumulation hours below $5^{\circ}C$, stopped date and period of rootstock growth, and sudden changed period of ABA contents, chicory has internal dormancy for two weeks from December 3 and low temperature requirement hours for the dormancy breaking is about 240.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.153-153
• /
• 2017

Potato (Solanum tubersosum L.) is susceptible to various environmental stresses such as frost, high temperature, and drought. Enhancement of potato drought tolerance can reduce yield loss under drought that has negative effect on potato tuber growth. Genetic engineering can be utilized to achieve this goal, but such approaches using endogenous potato genes have rarely been applied. Since unpredictable global weather changes cause more severe and frequent water limiting conditions, improvement of potato drought tolerance can minimize such adverse effects under drought and can impact on sustainable potato production. Genetic engineering can be utilized to improve potato drought tolerance, but such approaches using endogenous potato genes have rarely been applied. We were obtained AtbZIP28 gene transgenic potato plants. It is identified transcript levels at various stress conditions, polyethylene glycol (PEG), NaCl, abscisic ${\underline{acid}}$ (ABA). Also, For identification to regulate ER stress response genes in AtbZIP28 gene transgenic potato plant, we screened seven potato genes from RNA-seq analysis under TM treatment. Five and two genes were up- and down-regulated by TM, respectively. Their expression patterns were re-examined at stress agents known to elicit TM, DTT, DMSO and salt stress.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.90-90
• /
• 2017

Regulation of seed dormancy is important in many grains to prevent pre-harvest sprouting. To identify and understand the gene related to seed dormancy regulation, we have screened for viviparous phenotypes of rice mutant lines generated by insertion of Ds transposon in a Korean Japonica cultivar (Dongjin) background. One of the mutants, which represented viviparous phenotype, was selected for further seed dormancy regulation studies and designated dor1. The dor1 mutant has single Ds insertion in the second exon of OsDor1 gene encoding glycine-rich protein. The seeds of dor1 mutant showed a higher germination potential and reduced abscisic acid (ABA) sensitivity compared to wild type Dongjin. Over-expression of Dor1 complements the viviparous phenotype of dor1 mutant, indicating that Dor1 function in seed dormancy regulation. Subcellular localization assay of Dor1-GFP fusion protein revealed that the OsDor1 protein mainly localized to membrane and the localization of OsDOR1 was influenced by presence of a giberelin (GA) receptor OsGID1. Further bimolecular fluorescence complementation (BiFC) analysis indicated that OsDOR1 interact with OsGID1. The combined results suggested that OsDOR1 regulates seed dormancy by interacting with OsGID1 in GA response. Additionally, expression of OsDOR1 partially complemented the cold sensitivity of Escherichia coli BX04 mutant lacking four cold shock proteins, indicating that OsDOR1 possessed RNA chaperone activity.

• Journal of Plant Biotechnology
• /
• v.47 no.3
• /
• pp.194-202
• /
• 2020

The sweetpotatoes (Ipomoea batatas) generate adventitious roots (ARs) from cut stems that develop into storage roots and make for an important means of propagation. However, few studies have investigated the hormones involved in AR development in sweetpotato. In this study, the expression patterns of hormone-related genes involved in AR formation were identified using the transcriptome data. RNA-seq data from stems grown for 0 and 3 days after cutting were analyzed. In addition, hormone-related genes were identified among differentially expressed genes (DEGs) and filtered genes, and cluster analysis was used to characterize expression patterns by function. Most hormone-related regulated genes expressed 3 days after growing the cut stems were abscisic acid (ABA)-related genes, followed by ethylene- and auxin-related genes. For ABA, the biosynthesis genes (including genes annotated to NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3)) and signal transduction and perception genes (including genes annotated to PROTEIN PHOSPHATASE 2Cs (PP2Cs)) tended to decrease. Expression patterns of auxin- and ethylene-related genes differed by function. These results suggest that ABA, auxin, and ethylene genes are involved in AR formation and that they may be regulated in a hormone function-dependent manner. These results contribute to the identification of hormone functions during AR formation and may contribute to understanding the mechanism of AR formation in the sweetpotato.

• Molecules and Cells
• /
• v.26 no.3
• /
• pp.236-242
• /
• 2008

Invertase (${\beta}$-D-fructofuranosidase; EC 3.2.1.26) catalyzes the conversion of sucrose into glucose and fructose and is involved in an array of important processes, including phloem unloading, carbon partitioning, the response to pathogens, and the control of cell differentiation and development. Its importance may have caused the invertases to evolve into a multigene family whose members are regulated by a variety of different mechanisms, such as pH, sucrose levels, and inhibitor proteins. Although putative invertase inhibitors in the Arabidopsis genome are easy to locate, few studies have been conducted to elucidate their individual functions in vivo in plant growth and development because of their high redundancy. In this study we assessed the functional role of the putative invertase inhibitors in Arabidopsis by generating transgenic plants harboring a putative invertase inhibitor gene under the control of the CaMV35S promoter. A transgenic plant that expressed high levels of the putative invertase inhibitor transcript when grown under normal conditions was chosen for the current study. To our surprise, the stability of the invertase inhibitor transcripts was shown to be down-regulated by the phytohormone ABA (abscisic acid). It is well established that ABA enhances invertase activity in vivo but the underlying mechanisms are still poorly understood. Our results thus suggest that one way ABA regulates invertase activity is by down-regulating its inhibitor.

• BMB Reports
• /
• v.42 no.8
• /
• pp.486-492
• /
• 2009

OsDREB1D, a special DREB (dehydration responsive element binding protein) homologous gene, whose transcripts cannot be detected in rice (Oryza sativa L), either with or without stress treatments, was amplified from the rice genome DNA. The yeast one-hybrid assay revealed that OsDREB1D was able to form a complex with the dehydration responsive element/C-repeat motif. It can also bind with a sequence of LTRE (low temperature responsive element). To analyze the function of OsDREB1D, the gene was transformed and over-expressed in Arabidopsis thaliana cv. Columbia. Results indicated that the over-expression of OsDREB1D conferred cold and high-salt tolerance in transgenic plants, and that transgenic plants were also insensitive to ABA (abscisic acid). From these data, we deduced that this OsDREB1D gene functions similarly as other DREB transcription factors. The expression of OsDREB1D in rice may be controlled by a special mechanism for the redundancy of function.

• Molecules and Cells
• /
• v.37 no.11
• /
• pp.795-803
• /
• 2014

To withstand ever-changing environmental stresses, plants are equipped with phytohormone-mediated stress resistance mechanisms. Salt stress triggers abscisic acid (ABA) signaling, which enhances stress tolerance at the expense of growth. ABA is thought to inhibit the action of growth-promoting hormones, including brassinosteroids (BRs). However, the regulatory mechanisms that coordinate ABA and BR activity remain to be discovered. We noticed that ABA-treated seedlings exhibited small, round leaves and short roots, a phenotype that is characteristic of the BR signaling mutant, brassinosteroid insensitive1-9 (bri1-9). To identify genes that are antagonistically regulated by ABA and BRs, we examined published Arabidopsis microarray data sets. Of the list of genes identified, those upregulated by ABA but downregulated by BRs were enriched with a BRRE motif in their promoter sequences. After validating the microarray data using quantitative RT-PCR, we focused on RD26, which is induced by salt stress. Histochemical analysis of transgenic Arabidopsis plants expressing RD26pro:GUS revealed that the induction of GUS expression after NaCl treatment was suppressed by co-treatment with BRs, but enhanced by co-treatment with propiconazole, a BR biosynthetic inhibitor. Similarly, treatment with bikinin, an inhibitor of BIN2 kinase, not only inhibited RD26 expression, but also reduced the survival rate of the plant following exposure to salt stress. Our results suggest that ABA and BRs act antagonistically on their target genes at or after the BIN2 step in BR signaling pathways, and suggest a mechanism by which plants fine-tune their growth, particularly when stress responses and growth compete for resources.