• Molecules and Cells
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• v.45 no.8
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• pp.537-549
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• 2022

Preproenkephalin (PPE) is a precursor molecule for multiple endogenous opioid peptides Leu-enkephalin (ENK) and Met-ENK, which are involved in a wide variety of modulatory functions in the nervous system. Despite the functional importance of ENK in the brain, the effect of brain-derived factor(s) on PPE expression is unknown. We report the dual effect of neural epidermal growth factor (EGF)-like-like 2 (NELL2) on PPE gene expression. In cultured NIH3T3 cells, transfection of NELL2 expression vectors induced an inhibition of PPE transcription intracellularly, in parallel with downregulation of protein kinase C signaling pathways and extracellular signal-regulated kinase. Interestingly, these phenomena were reversed when synthetic NELL2 was administered extracellularly. The in vivo disruption of NELL2 synthesis resulted in an increase in PPE mRNA level in the rat brain, suggesting that the inhibitory action of intracellular NELL2 predominates the activation effect of extracellular NELL2 on PPE gene expression in the brain. Biochemical and molecular studies with mutant NELL2 structures further demonstrated the critical role of EGF-like repeat domains in NELL2 for regulation of PPE transcription. These are the first results to reveal the spatio-specific role of NELL2 in the homeostatic regulation of PPE gene expression.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.791-801
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• 2022

Boil-dried concentrates (BDC) and steam-dried concentrates (SDC) were prepared from highly nutritious olive flounder Paralichthys olivaceus roes (OFR) as seafood processing by-products and their nutritional characteristics were investigated. Although SDS-PAGE profiles of the BDC and SDC proteins were similar to each other, it was observed that three of the five OFR protein bands in the 50-100 kDa range had disappeared. We also detected significant differences in the Hunter's color of the two concentrates in terms of color difference (𝚫E) and whiteness. The recovery amounts of BDC and SDC prepared from 100 g of OFR were 18.6 and 21.4 g, respectively, with respective protein contents of 67.7% and 68.9%. The main amino acids of OFR and concentrate proteins were valine, leucine, lysine, arginine, aspartic acid, glutamic acid and alanine, whereas major minerals were sulfur, potassium, sodium and phosphorus, the amounts of which in concentrates had been significantly reduced. We established that by sterilizing, inactivating endogenous enzymes, and inhibiting microbial growth, the cook-dried process contributes to enhancing the concentration and storage stability of nutrients by reducing water activity, volume, and weight. Accordingly, we suggest that concentrates (BDC and SDC) prepared from OFR have considerable potential as nutritionally fortified materials.

• Journal of Plant Biotechnology
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• v.49 no.4
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• pp.271-291
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• 2022

Pectin methylesterase (PME) plays an important role in vegetative and reproductive development and biotic/abiotic stress responses by regulating the degree of methyl-esterification of pectic polysaccharides in the plant cell wall. PMEs are encoded by a large multigene family in higher land plant genomes. In general, the expression of plant PME genes shows tissue- or cell-specific patterns and is induced by endogenous and exogenous stimuli. In this study, we identified PME multigene family members (CsPMEs) from the sweet orange genome and report detailed molecular characterization and expression profiling in different citrus tissues and two fruit developmental stages. We also discussed the possible functional roles of some CsPME genes by comparing them with the known functions of PMEs from other plant species. We identified 48 CsPME genes from the citrus genome. A phylogenetic tree analysis revealed that the identified CsPMEs were divided into two groups/types. Some CsPMEs showed very close phylogenetic relationships with the PMEs whose functions were formerly addressed in Arabidopsis, tomato, and maize. Expression profiling showed that some CsPME genes are highly or specifically expressed in the leaf, root, flower, or fruit. Based on the phylogenetic relationships and gene expression profiling results, we suggest that some CsPMEs could play functional roles in pollen development, pollen tube growth, cross incompatibility, root development, embryo/seed development, stomata movement, and biotic/abiotic stress responses. Our results shed light on the biological roles of individual CsPME isoforms and contribute to the search for genetic variations in citrus genetic resources.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.21-30
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• 1975

The purpose of this paper is to elucidate physiologically the cause of the hastening germination of dormant Taxus cuspidata seeds by stratification. During the stratification the exchange of chemical substances such as sugar, protein, starch and fat were observed, and growth promoting and inhibiting substances were extracted and seperated from seeds by the conventional chromatographic method with coleoptile straight-growth test. An intensive investigation was made on the balance between the promoters and inhibitors. consequently, it was confirmed that germination of seeds was accelerated with exchange of chemical substances by stratification. The results obtained may be summarized as follows: 1. During the stratification growth promoters were increased and growth inhibitors were decreased rapidly in the endosperm of seeds. Thus, it was presumed that hastening germination was controlled by balace between the promoters and inhibitors from November to next March after a year's stratification. On the other hand growth promoters were almost constant and growth inhibitors were decreased rapidly in the seed coats, and it was presumed that hastening germination was influenced by exchange of inhibitors more than by that of promoters. 2. As a results of germination test of lettuce seeds, it was generalized that hastening germination was controlled by a decreased amount of growth inhibitors more than by an increased amount of promoters. 3. During the stratification sugar and crude protein contents were increased gradully with moisture content, while starch and crude fat were decreased in endosperm of seeds. So it was assumed that the exchange of these chemical substances was closely related to the germination of seeds.

• Journal of Life Science
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• v.18 no.7
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• pp.931-939
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• 2008

The purpose of this study was to determine the effect of energy supplement on responses of plasma insulin-like growth factor (IGF)-1 and IGF binding proteins (IGFBPs) to growth hormone-releasing peptide-2 (GHRP-2) administration in normal protein-fed wethers, and to observe the effect of GHRP-2 treatment on hepatic growth hormone (GH) receptor in well-fed wethers. Plasma IGF-1 and 39-42 kDa IGFBP-3 during the HENP (CP, crude protein 0.34 and TDN, total digestible nutrients 1.83 kg/day DM, dry matter intake) treatment period were higher than in the LENP (CP 0.32 kg and TDN 0.87 kg/day DM intake) period (P<0.05). The response of GH was stimulated by GHRP-2 ($12.5\;{\mu}g/kg$ body weight/day) administration during both of the feed treatment periods (P<0.05). The area under curve (AUC) increment and average concentration of GH (0-180 min) with GHRP-2 administration was higher during HENP treatment than LENP treatment (P<0.01). During the HENP treatment period from day 1 to day 7 of twice daily GHRP-2 treatment, the plasma IGF-1 increment was increased on days 2, 6 and 7 of GHRP-2 administration (P<0.05). On the basis of ligand blotting, the proportions of plasma 39-43 kDa IGFBP-3 during the HENP treatment period only showed a significant difference on days 6 and 7 with GHRP-2 administration. No significant difference in the specific binding of $^{125}I-labeled$ oGH to hepatic membranes was detected between the saline and GHRP-2 treatments of the HENP-fed wethers. These results suggest that the nutritional balance between energy and protein may affect the endogenous GH / IGF-1 axis as well as plasma IGFBP-3 levels.

• 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.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.17-17
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• 2010

Ethylene, known as a stress hormone regulate wide developmental processes including germination, root hair initiation, root and shoot primordial formation and elongation, leaf and flower senescence and abscission, fruit ripening. The acceleration of ethylene biosynthesis in plant associated with environmental and biological stresses. 1-Aminocycloprophane-1-carboxlyate deaminase(ACCD) is an enzyme that cleaves ACC into and ammonia, a precursor of the plant hormone ethylene. Plant growth-promoting rhizobacteria (PGPR) having ACCD can decrease endogenous ACC level of tissue, resulting in reduced production of ethylene in plants. ACC deaminse was a key enzyme for protect stressed plants from injurious effects of ethylene. ACCD gene was encoded from Pseudomonas flourescens, PGPR and was cloned in Escherichia coli. We expressed the recombinant ACCD(rACCD) containing 357 amino acids with molecular weight 39 kDa that revealed by SDS-PAGE and western blot. The rACCD was purified by Ni-NTA purification system. The active form of rACCD having enzyme activity converted ACC to a-ketobutyrate. The optimal pH for ACC deaminase activity was pH 8.5, but no activity below pH 7.0 and a less severe tapering activity at base condition resulting in loss of activity at over pH 11. The optimal temperature of the enzyme was $30^{\circ}$ and a slightly less severe tapering activity at 15 - 30$^{\circ}$, but no activity over $35^{\circ}$. P. flourescens ACC deaminase has a highly conserved residue that plays in allowing substrate accessibility to the active sites. The enzymatic properties of this rACCD will provide an important reference for analysis of newly isolated ACCD and identification of newly isolated PGPR containing ACCD.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.2
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• pp.112-119
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• 2009

Extracellular matrix(ECM) is known to function as a reservoir of endogenous growth factors, can be an effective delivery system of growth factor that easily lost bioactivity in solution. Fibrillar collagens like type I collagen, are the major constituent of the ECM and structural protein of bone. Also, it can be a scaffold for osteoblast migration. The purpose of this study was to compare the effects of absorbable Atelo-collagen Sponge($Teruplug^{(R)}$) insertion in tooth extraction sites on periodontal healing of the mandibular second molar after the extraction of the impacted third molar. The study population comprised 31 cases who had been scheduled for surgical removal of impacted mandibular third molars. All patients were in good general health and were not using any medication that would influence wound healing after surgery. In 15 cases control group, none was inserted into the tooth extraction site. In 16 cases experimental groups, $Teruplug^{(R)}$ was inserted into the tooth extraction site. We evaluated tooth mobility, pocket depth, gingival margin level preoperatively and 1 week, 2 weeks, 4 weeks, and 3 months postoperatively. The change was compared with two groups using Mann-Whitney test. The results were as follows. 1. There was no significant change of tooth mobility on both groups. 2. There was tendency of decreasing of previous pocket depth causing tooth extraction on both groups. 3. On gingival margin level, there was various change according to initial swelling and loss of attachment on both groups. 4. There was tendency of decreasing of gingival margin level on both groups because of removal of inflammation and decreasing of previous pocket depth. 5. There was large change of pocket depth on buccal middle, distal, lingual distal area because of tooth extraction and bone reduction. Compared with the control group and experimental group, we observed significant difference during some periods. The results of this study suggest that absorbable atelo-collagen sponge($Teruplug^{(R)}$) is relatively favorable bone void filler with prevention of tissue collapse, food packing and enhance periodontal healing.

• Korean Journal of Animal Reproduction
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• v.21 no.1
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• pp.61-69
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• 1997

The present study was carried out to investigate the effects of EGF and anti-EGF on early embryonic development and hatching in mice. Developmental and hatching rates of mouse em-bryos from 2-cell to morular stage which were cultured in Ham's FlO medium supplemented with EGF (1-1,000 ng/ml) or anti-EGF (whole serum diluted from 1:10 to 1:1,000) were compared to those of control When mouse early 2-cell embryos were cultured in the EGF supplemented medium, blastulation was accelerated compared with control. Hatching rate was also significantly (p

• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.33-37
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• 2012

Differential capacity of the parthenogenetic embryonic stem cells (PESCs) is still under controversy and the mechanisms of its neural induction are yet poorly understood. Here we demonstrated neural lineage induction of PESCs by addition of insulin-like growth factor-2 (Igf2), which is an important factor for embryo organ development and a paternally expressed imprinting gene. Murine PESCs were aggregated to embryoid bodies (EBs) by suspension culture under the leukemia inhibitory factor-free condition for 4 days. To test the effect of exogenous Igf2, 30 ng/ml of Igf2 was supplemented to EBs induction medium. Then neural induction was carried out with serum-free medium containing insulin, transferrin, selenium, and fibronectin complex (ITSFn) for 12 days. Normal murine embryonic stem cells derived from fertilized embryos (ESCs) were used as the control group. Neural potential of differentiated PESCs and ESCs were analyzed by immunofluorescent labeling and real-time PCR assay (Nestin, neural progenitor marker; Tuj1, neuronal cell marker; GFAP, glial cell marker). The differentiated cells from both ESC and PESC showed heterogeneous population of Nestin, Tuj1, and GFAP positive cells. In terms of the level of gene expression, PESC showed 4 times higher level of GFAP expression than ESCs. After exposure to Igf2, the expression level of GFAP decreased both in derivatives of PESCs and ESCs. Interestingly, the expression level of $Tuj1$ increased only in ESCs, not in PESCs. The results show that IGF2 is a positive effector for suppressing over-expressed glial differentiation during neural induction of PESCs and for promoting neuronal differentiation of ESCs, while exogenous Igf2 could not accelerate the neuronal differentiation of PESCs. Although exogenous Igf2 promotes neuronal differentiation of normal ESCs, expression of endogenous $Igf2$ may be critical for initiating neuronal differentiation of pluripotent stem cells. The findings may contribute to understanding of the relationship between imprinting mechanism and neural differentiation and its application to neural tissue repair in the future.