• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.81-85
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• 2001

The experiment was conducted to know the effect of plant growth regulators on axillary bud elongation from in vitro stem cutting and the possibility of virus-free stock production. Axillary buds were well elongated in 3/4 strength MS medium supplemented with 0.1 or 0.5 mg/1 BA and 0.05 mg/1 NAA. Transferred plantlets could be established well in vermiculite and peat moss mixture (3:1, v/v) compare to other mixtures. In virus indexing, all the varieties of mother plants were infected by GLRV Ⅲ. Infected percentages of the three varieties were ranged from 30% to 75%. But negative response was revealed against the other species of virus, GLRV Ⅰ, GFLV and ArMV. Plantlet of 'Schuyler' and 'Muscat of Alexandria', which were cultured in vitro, showed positive response against GLRV Ⅲ and infected percentage of the former was 37.5% but the latter, 12.5%. On the other hand, that of 'Campbell Early' negativiely responded against all the species of virus indexed.

• Journal of Life Science
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• v.19 no.11
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• pp.1506-1513
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• 2009

RGS proteins have been identified as negative regulators of G protein signalling pathways and attenuate the activity of GPCR receptors. However, information on the regulatory effects of RGS proteins in the activity of cannabinoid receptors is limited. In this study, the role of RGS proteins on the signal transduction of the CB2 cannabinoid receptor was investigated in HEK293 cells co-transfected with CB2-receptors and plasmids encoding RGS2, RGS3, RGS4 and RGS5. Treatment of cells with WIN55, 212-2, a CB2 receptor agonist, inhibited forskolin-induced cAMP response element (CRE) activity in CB2-transfected HEK293 (CB2-HEK293) cells. This inhibitory effect of WIN 55, 212-2 on CRE activity was reversed by co-transfection of CB2-HEK293 cells with RGS3, but not with RGS2, RGS4 and RGS5. However, endogenous RGS3 protein knocked down by a small interfering siRNA targeting RGS3 gene enhanced inhibition of forskolin induced CRE activity via agonist induced CB2 receptor signal transduction. These results indicate the functional role of endogenous RGS protein in cannabinoid signaling pathways and define receptor-selective roles of endogenous RGS3 in modulating CRE transcriptional responses to agonist induced CB2 receptor activity.

• Genes and Genomics
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• v.40 no.11
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• pp.1181-1197
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• 2018

Tropical plant rubber tree (Hevea brasiliensis) is the sole source of commercial natural rubber and low-temperature stress is the most important limiting factor for its cultivation. To characterize the gene expression profiles of H. brasiliensis under the cold stress and discover the key cold stress-induced genes. Three cDNA libraries, CT (control), LT2 (cold treatment at $4^{\circ}C$ for 2 h) and LT24 (cold treatment at $4^{\circ}C$ for 24 h) were constructed for RNA sequencing (RNA-Seq) and gene expression profiling. Quantitative real time PCR (qRT-PCR) was conducted to validate the RNA-Seq and gene differentially expression results. A total of 1457 and 2328 differentially expressed genes (DEGs) in LT2 and LT24 compared with CT were respectively detected. Most significantly enriched KEGG pathways included flavonoid biosynthesis, phenylpropanoid biosynthesis, plant hormone signal transduction, cutin, suberine and wax biosynthesis, Pentose and glucuronate interconversions, phenylalanine metabolism and starch and sucrose metabolism. A total of 239 transcription factors (TFs) were differentially expressed following 2 h or/and 24 h of cold treatment. Cold-response transcription factor families included ARR-B, B3, BES1, bHLH, C2H, CO-like, Dof, ERF, FAR1, G2-like, GRAS, GRF, HD-ZIP, HSF, LBD, MIKC-MADS, M-type MADS, MYB, MYB-related, NAC, RAV, SRS, TALE, TCP, Trihelix, WOX, WRKY, YABBY and ZF-HD. The genome-wide transcriptional response of rubber tree to the cold treatments were determined and a large number of DEGs were characterized including 239 transcription factors, providing important clues for further elucidation of the mechanisms of cold stress responses in rubber tree.

• BMB Reports
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• v.55 no.4
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• pp.198-203
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• 2022

As negative regulators of cytokine signaling pathways, suppressors of cytokine signaling (SOCS) proteins have been reported to possess both pro-tumor and anti-tumor functions. Our recent studies have demonstrated suppressive effects of SOCS1 on epithelial to mesenchymal signaling in colorectal cancer cells in response to fractionated ionizing radiation or oxidative stress. The objective of the present study was to determine the radiosensitizing action of SOCS1 as an anti-tumor mechanism in colorectal cancer cell model. In HCT116 cells exposed to ionizing radiation, SOCS1 over-expression shifted cell cycle arrest from G2/M to G1 and promoted radiation-induced apoptosis in a p53-dependent manner with down-regulation of cyclin B and up-regulation of p21. On the other hand, SOCS1 knock-down resulted in a reduced apoptosis with a decrease in G1 arrest. The regulatory action of SOCS1 on the radiation response was mediated by inhibition of radiation-induced Jak3/STAT3 and Erk activities, thereby blocking G1 to S transition. Radiation-induced early ROS signal was responsible for the activation of Jak3/Erk/STAT3 that led to cell survival response. Our data collectively indicate that SOCS1 can promote radiosensitivity of colorectal cancer cells by counteracting ROS-mediated survival signal, thereby blocking cell cycle progression from G1 to S. The resulting increase in G1 arrest with p53 activation then contributes to the promotion of apoptotic response upon radiation. Thus, induction of SOCS1 expression may increase therapeutic efficacy of radiation in tumors with low SOCS1 levels.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.47-52
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• 2003

Anthers from several lines of carrot (Daucus carota L.) were plated on the semi-solid B$_{5}$, basal medium supplemented with 2,4-D and NAA at two concentrations, 1.0 and 2.0 mg/L plus 0.2 mg/L BAP (benzylaminop-urine). Anthers of the most lines on the B$_{5}$ basal medium with 2,4-D showed higher percentages of callus formation than those with NAA. Particularly, in line 45477, highest percentages of callus formation (50%) were observed on B$_{5}$ medium with 1.0 mg/L 2,4-D plus 0.2 mg/L BAP. With 1.0 mg/L 2,4-D, two months was sufficient for initiation of callus development. Calli were regenerated into plantlets through embryogenesis onto regeneration medium without any growth regulators. When callus showing yellowish and soft structure was cultured, it yielded green plants at high regeneration rates, The response of anthers in callus induction and plant regeneration was different among lines investigated. Optimal callus induction and plant regeneration could be obtained through manipulating the concentration of growth regulators. Plantlets after transfer to perlite were grown successfully in greenhouse conditions. Anther culture of carrot will be used as a useful breeding tool in future.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.78-83
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• 1987

This study was attempted to evaluate the combining effect of HBR (homobrassinolide) with the known growth regulators such as GA (gibberellic acid), BA(6-benzyl aminopurine), IAA (indole-3-acetic acid), B-9 (N-dimethylamino succinamic acid) and CCC (2-chloroethyl-trimethylammonium chloride) on the growth of radish hypocotyl. A single application of HBR increased hypocotyl growth as its rates increased from 0.1 to 1.0 ppm, showing a maximum increase at 1.0 ppm. GA and BA had no direct effects on hyopcotyl growth, but IAA showed some effect as its concentration increased. However, the mixed application of HBR with GA, BA and IAA increased the length of radish hypocotyl as the concentration of HBR became higher. The mixture of HBR with GA and BA showed antagonistic reaction on radish hypocotyl growth, but synergistic effect was shown in the higher rate mixture of HBR with IAA in the range of HBR at 0.03 to 0.30 ppm with IAA at 3.0 to 10.0 ppm, but antagonistic or additive response at the mixture of low rates. An increased growth of hypocotyl by HBR was ified by CCC, showing the strong antagonistic reaction, but B-9 was not able to ify HBR's effect on hypocotyl growth.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.45-49
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• 2002

The leaf and petiole segments of Farfugium japonica were cultured to investigate the influence of growth regulators on their callus induction and plant regeneration. The callus induction and growth showed a good response both leaf and petiole on MS media supplemented with 1∼2 mg/L 2,4-D and 1∼2 mg/L BA. Callus induction and growth were more effective in petiole segments than leaf one. The highest percentage of plant regeneration was obtained from 60-day-old calli on MS medium supplemented with 1 mg/L NAA and 2 mg/L BA. When subcultured to the same medium for about 60 days, multiple shoots were developed from regenerating callus. The shoots produced roots after transferring to rooting medium containing 0.5 mg/L IAA. The plantlets over 50 mm in height were successfully acclimatized in vermiculite, and the survival rate was over 95%.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1029-1036
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• 2024

Drawing on the deep experience and understanding of the principles of nuclear safety, as well as many years of nuclear power plant design and operation, the EDF led NUWARD SMR Project is developing a design for a Small Modular Reactor (SMR) of 340 MWe composed of two 170 MWe independent units, that will supplement the offering of high-output nuclear reactors, especially in response to specific needs such as replacement of fossil-fuelled power plants. NUWARD SMR is a mix of proven and innovative design features that will make it more commercially competitive, while integrating safety features that comply with the highest international standards. Following the principles of redundancy and diversity and rigorous application of Defence in Depth (DID), with an international view on nuclear safety licensing, the Project also incorporates new safety approaches into its design development. The NUWARD SMR Project has been in development for a number of years, it entered conceptual design formally in mid-2019 and entered Basic Design in 2023. The objective of the concept design phase was to confirm the project technological choices and to define the first design configuration of the NUWARD SMR product, to document it, in order to launch pre-licensing with the French Safety Authority (ASN) and to define its estimated cost and its subsequent development and construction schedules. As a delivery milestone the Safety Options file (called the Dossier d'Options de Sûreté (DOS)) has been submitted to ASN in July 2023 for their opinion. An integral part of the NUWARD SMR Project, is not only to deliver a design suitable for France and to satisfy French regulation, but to develop a product suitable and indeed desirable, for the international market, with a first focus in Europe. In order to achieve its objectives and realise its market potential, the NUWARD SMR Project needs to define and realise its safety approach within an international environment and that is the key subject of this paper. The following paper: • Summarises the foundation principles and technological background which underpin the design; • Contextualises the key design features with regard to the international safety regulatory framework with particular emphasis on innovative passive safety aspects; • Illustrates the Project activities in preparation for first licensing in France, and also a wider international view via the ASN led Joint Early Review of the NUWARD SMR design, including Finnish and Czech Republic regulators, recently joined by the Swedish, Polish and Dutch regulators; • Articulates the collaborative approach to design development from involvement with the Project partners (the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Naval Group, TechnicAtome, Framatome and Tractebel) to the establishment of the International NUWARD Advisory Board (INAB), to gain greater international insight and advice; • Concludes with the focus on next steps into detailed design development, standardisation of the design and its simplification to enhance its commercial competitiveness in a context of further harmonisation of the nuclear safety and licensing requirements and aspirations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.288-298
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• 1992

Since the major important factors limiting plant growth and crop productivity are environmental stresses, of which low temperature is the most serious. It has been well known that many physiological processes are alterant in response to the environmental stress. With regard to the relationship between plant hormones and the regulation of chilling tolerance in rice seedlings, the major physiological roles of plant hormones: abscisic acid, ethylene and polyamines are evaluated and discussed in this paper. Rice seedlings were grown in culture solution to examine the effect of such plant hormones on physiological characters related to chilling tolerance and also to compare the different responses among tested cultivars. Intact seedlings about 14 day-old were chilled at conditions of 5$^{\circ}C$ and 80% relative humidity for various period. Cis-(＋)-ABA content was measured by the indirect ELISA technique. Polyamine content and ethylene production in leaves were determined by means of HPLC and GC respectively. Chilling damage of seedlings was evaluated by electrolyte leakage, TTC viability assay or servival test. Our experiment results described here demonstrated the physiological functions of ABA, ethylene, and polyamines related to the regulation of chilling tolerance in rice seedlings. Levels of cis-(＋)-ABA in leaves or xylem sap of rice seedlings increased rapidly in response to 5$^{\circ}C$ treatment. The tolerant cultivars had significant higher level of endogenous ABA than the sensitive ones. The ($\pm$)-ABA pretreatment for 48 h increased the chilling tolerance of the sensitive indica cultivar. One possible function of abscisic acid is the adjustment of plants to avoid chilling-induced water stress. Accumulation of proline and other compatible solutes is assumed to be another factor in the prevention of chilling injuies by abscisic acid. In addition, the expression of ABA-responsive gene is reported in some plants and may be involving in the acclimation to low temperature. Ethylene and its immediate precusor, 1-amincyclopropane-1-carboxylic acid(ACC) increased significantly after 5$^{\circ}C$ treatment. The activity of ACC synthase which converts S-adenosylmethionine (SAM) to ACC enhanced earlier than the increase of ethylene and ACC. Low temperature increased ACC synthase activity, whereas prolonged chilling treatment damaged the conversion of ACC to ethylene. It was shown that application of Ethphon was beneficial to recovering from chilling injury in rice seedlings. However, the physiological functions of chilling-induced ethylene are still unclear. Polyamines are thought to be a potential plant hormone and may be involving in the regulation of chilling response. Results indicated that chilling treatment induced a remarkable increase of polyamines, especially putrescine content in rice seedlings. The relative higher putrescine content was found in chilling-tolerant cultivar and the maximal level of enhanced putrescine in shoot of chilling cultivar(TNG. 67) was about 8 folds of controls at two days after chilling. The accumulation of polyamines may protect membrane structure or buffer ionic imbalance from chilling damage. Stress physiology is a rapidly expanding field. Plant growth regulators that improve tolerance to low temperature may affect stress protein production. The molecular or gene approaches will help us to elucidate the functions of plant hormones related to the regulation of chilling tolerance in plants in the near future.

• Journal of Life Science
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• v.31 no.9
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• pp.796-805
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• 2021

Hepatic endoplasmic reticulum (ER) stress contributes to the development of steatosis and insulin resistance. The components of unfolded protein response (UPR) regulate lipid metabolism. Recent studies have reported an association between ER stress and aberrant cellular lipid control; moreover, research has confirmed the involvement of sterol regulatory element-binding proteins (SREBPs)-the central regulators of lipid metabolism-in the process. However, the exact role of SREBPs in controlling lipid metabolism during ER stress and its contribution to fatty liver disease remain unknown. Here, we show that SREBP-1c deficiency protects against ER stress-induced hepatic steatosis in mice by regulating UPR, inflammation, and fatty acid oxidation. SREBP-1c directly regulated inositol-requiring kinase 1α (IRE1α) expression and mediated ER stress-induced tumor necrosis factor-α activation, leading to a reduction in expression of peroxisome proliferator-activated receptor γ coactivator 1-α and subsequent impairment of fatty acid oxidation. However, the genetic ablation of SREBP-1c prevented these events, alleviating hepatic inflammation and steatosis. Although the mechanism by which SREBP-1c deficiency prevents ER stress-induced inflammatory signaling remains to be elucidated, alteration of the IRE1α signal in SREBP-1c-depleted Kupffer cells might be involved in the signaling. Overall, the results suggest that SREBP-1c plays a crucial role in the regulation of UPR and inflammation in ER stress-induced hepatic steatosis.