• Molecules and Cells
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• v.39 no.8
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• pp.587-593
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• 2016

As sessile organisms, plants must be able to adapt to the environment. Plants respond to the environment by adjusting their growth and development, which is mediated by sophisticated signaling networks that integrate multiple environmental and endogenous signals. Recently, increasing evidence has shown that a bHLH transcription factor PIF4 plays a major role in the multiple signal integration for plant growth regulation. PIF4 is a positive regulator in cell elongation and its activity is regulated by various environmental signals, including light and temperature, and hormonal signals, including auxin, gibberellic acid and brassinosteroid, both transcriptionally and post-translationally. Moreover, recent studies have shown that the circadian clock and metabolic status regulate endogenous PIF4 level. The PIF4 transcription factor cooperatively regulates the target genes involved in cell elongation with hormone-regulated transcription factors. Therefore, PIF4 is a key integrator of multiple signaling pathways, which optimizes growth in the environment. This review will discuss our current understanding of the PIF4-mediated signaling networks that control plant growth.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.193-194
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• 2001

To determine for the hybridization, we have investigated by UV spectroscopic method. This complex behavior as nonelectrolytes in polar aprotic solution with molar conductivities. The technoques of pulse and cyclic voltammetry have been applied to the determination of $(E_{1/2})_{2}$-$(E_{1/2})_{1}$ for two-step electrochemical charge transfers. A simple amplitude has been derived for the dependence of the differential-pulse response on $(E_{1/2})_{1}$ and $(E_{1/2})_{2}$. The use of the peak-to-peak separation in cyclic voltammetry has also been evaluated. Comparison with a differential pulse and cyclic voltammetry methods shows agreement of comproportionation constant$(K_{c})$ within 50%.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.53-58
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these "environmental or abiotic stresses", which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity, In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.n factors.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.180-180
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• 2003

Peroxisome proliferator-activated receptor gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, is involved in the suppression of growth of several types of tumors such as liposarcoma, cancers of breast, prostate, and colon, possibly through induction of cell cycle arrest and/or apoptosis.(omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.183.1-183.1
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• 2003

Endometriosis is classically defined as the growth of endometrial glands and stroma at extra-uterine sites. Although it is a common gynecological problem accompanied by chronic pelvic pain, infertility, and adhesion formation, the etiology of this disease is unknown. Endometriosis pathogenesis may involve endocrine and immune dysregulation since uterine endometrial growth is regulated by sex hormone in concert with bioactive mediators produced by uterine immune and endocrine cells. (omitted)

• Biomedical Science Letters
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• v.15 no.3
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• pp.249-255
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• 2009

All living things have been developed efficient strategies to cope with external and internal environmental changes via a process termed 'homeostasis'. However, chronic prenatal maternal stress may significantly contributes to pregnancy complications by disturbing hypothalamic-pituitary-adrenal (HPA) axis and the automatic nervous system (ANS), and results in unfavorable development of the fetus. Dysregulation of these two major stress response systems lead to the increased secretion of the glucocorticoids (GCs) which are known to be essential for normal development and the maturation of the central nervous system. As Hox genes are master key regulators of the embryonic morphogenesis and cell differentiation, we aimed to determine the effects of dexamethasone, a potent synthetic glucocorticoid, on gene expression in mesenchymal stem cell C3H10T1/2. Analysis of 39 Hox genes based on reverse transcription PCR (RT-PCR) method revealed that the expression patterns of Hox genes were overall upregulated by long dexametasone treatment. These results indicate that maternal stress may have a deleterious effect on early developing embryo through the stress hormone, glucocorticoid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.1
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• pp.1-6
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• 2008

The changes in osmolality and the gene expression profiles of prolactin (PRL) and growth hormone (GH) with rapid changes in salinity were compared in the eel (Anguilla japonica), crucian carp (Carassius carassius), and masu salmon (Oncorhynchus masou). Fish stocked in freshwater (FW) were abruptly transferred to experimental tanks containing FW, 50% seawater (50% SW), or 100% SW (SW). Blood samples and pituitary glands were collected 2 and 24 hrs after the exposure. No mortality was observed in SW eel (n=6), whereas all of the crucian carp (n=6) and two masu salmon (n=6) exposed to SW died after land 24 hrs, respectively. The PRL mRNA levels of the eel and masu salmon decreased in 50% SW and SW compared to those of the fish kept in FW after 24 hrs, whereas the PRL levels of crucian carp were higher in 50% SW than in FW. Unlike the PRL mRNA levels, the GH mRNA levels of the eel did not differ significantly among three different salinities, while the GH mRNA levels of crucian carp and masu salmon increased significantly in 50% SW and SW after 24 hrs. The serum osmolalities increased marginally in the eel and masu salmon in 50% SW at 24 hrs (19% and 9%, respectively), whereas those of crucian carp increased abruptly in 50% SW (50% increase). These results suggest that the synthesis of PRL and GH is important in relation to the osmoregulatory system with environmental changes in salinity.

• Development and Reproduction
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• v.23 no.1
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• pp.35-42
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• 2019

Fish shows great difference in growth rate between individuals during larval development and early growth. This difference seriously reduces the production efficiency in fish culture. Growth hormone (GH)/Insulin-like growth factor 1 (IGF1) system is said to play some pivotal roles in fish growth. In this study, we investigated differences of GH, IGF1 and GHR gene expressions in juvenile red spotted grouper (Epinephelus akaara) with different growth performance. Red spotted groupers were reared under the same environmental condition (water temperature $24{\pm}1^{\circ}C$, natural light) for 96 days after hatching. They were divided into 3 groups by size (fast growing, middle growing and slow growing groups: FGG, MGG, and SGG, respectively). RNA was extracted from the brain, liver and muscle tissues from each group, and target gene expression was examined by real-time PCR. In the brain with pituitary gland, expression of GH gene in FGG was significantly higher than the expression in SGG, but the expression of IGF1 and GHR genes in the muscle was highest in SGG. Difference of GHR and IGF1 mRNA in the liver between groups with different growth performance was less clear than that in other tissues, although level of IGF1 mRNA was higher in SGG than in MGG. These results suggest that hormonal governing of growth is not the same in fast growing and slow growing fish, and size grading could cause a shift of hormonal state and growth pattern in this species.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.125-132
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• 2011

Drought is a major limiting factor in turfgrass management. Turfgrass responses to water deficit depend on the amount and the rate of water loss as well as the duration of the stress condition. This review paper was designed to understand responses such as photosynthesis, canopy spectral reflectance, plant cell, root, hormone and protein alteration when turfgrass got drought stress. Furthermore, mechanisms to recover from drought conditions were reviewed in detail. However, there are still many questions regarding plant adaptation to water deficit. It is not clear that the mechanism by which plants detect water deficit and transfer that signal into adaptive responses. Turfgrass research should focus on the best management practices such as how to enhance the ability of self-defense mechanism through understanding plant responses by environmental stress.

• Korean journal of applied entomology
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• v.34 no.1
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• pp.20-32
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• 1995

Adult diapause in insects is characterized by suppression of reproductive development. It is induced by environmental cues such as photoperiod, temperature, food availability, and other conditions Diapause-inducing environment is recognized and analyzed by the brain of the insects. The interpreted information is conveyed via endocrine system to target tissues such as ovaries, fat body, and other tissues. From this signal hierarchy of a brain-endocrine-target tissue axis, several factors are involved to express a diapause trait in a quantitative mode, even though the insects show a binomial phenotye between being in diapause or not. Recent works estimated that the number of the factors is relatively small by a series of crossing trials between high and low diapause lines. Heritability of the diapause is quite high (ca. 70%) in some species. Epistasis, sex-linkage, pleiotropism, and other nongenetic components also affect diapause inheritance. Most physiological studies have been focused on control mechanisms of the juvenile hormone (JH) synthesis in corpora allata (CA) because JH level in hemolymph of teneral adults is critical to decide a later developmental mode. Allatostatin, an antagonizer of JH synthesis, has been believed to be a potent brain message to CA for adult diapause induction.