• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.214-220
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• 1993

The mating type a of yeast, Saccharomyces cerevisiae mutant with hmla2-102 and sir3-8ts was changed to type alpha by changing the growth temperature from 25C to 35C. A temperature-sensitive expression vector system was constructed using mating factor alpha1 (Mfalpha1) gene encoding alpha factor which is expressed in the type alpha cells. Vectors with different copy numbers were constructed by joining the promoter and pre or prepro-secretion single sequence of Mfalpha1 to promoterless PHO5' gene as a reporter gene.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3830-3833
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• 2010

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.269-275
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• 1996

Biosynthesis and secretion of anterior pituitary hormones are under the control of specific hypothalamic stimulatory and inhibitory factors. Among them, Growth Hormone Releasing Hormone (GHRH) is the major stimulator of pituitary somatotrophs activating GH gene expression and secretion. Human GHRH is a polypeptide of 44 amino acids initially isolated from pancreatic tumors, and the gene for the hypothalamic form of GHRH is organized into 5 exons spanning over 10 kilobases (kb) on genomic DNA and encodes a messenger RNA of 700-750 nucleotides. Several neuropeptides classically associated with the hypothalamus have been found in the extrahypothalamic regions, suggesting the existence of novel sources, targets and functions. GHRH-like immunoreactivity has been found in several peripheral sites, including placenta, testis, and ovary, indicating that GHRH may also have regulatory roles in peripheral reproductive organs. Furthermore, higher molecular weight forms of the GHRH transcripts were identified from these organs (1.75 kb in testis; 1.75 and >3 kb in ovary). These tissue-specific expression of GHRH gene suggest the existence of unique regulatory mechanism of GHRH expression and function in these organs. In fact, placenta-specific and testis-specific promoters for GHRH transcripts which are located in about 10 kb upstream region of hypothalamic promoter were reported. The use of unique promoters in extrahypothalamic sites could be refered in a different control of GHRH gene and different functions of the translated products in these tissues. Somatotrophs and lactotrophs have been thought to be derived from a common bipotential progenitor, the somatolactotrophs, which give origins to either phenotypes. Although the precise mechanism responsible for the lactotroph differentiation in the anterior pituitary gland has not been yet clalified, there are several candidators for the generation of lactotrophs. In human, the presence of GHRH peptides with different size from authentic hypothalamic form in the normal anterior pituitary and several types of adenoma were demonstrated. Recently our group found the existence of immunoreactive GHRH and its transcript from the normal rat anterior pituitary (gonadotroph> somatotroph> lactotroph), and the GHRH treatment evoked the increased proliferation rate of anterior pituitary cells in vitro. The transgenic mouse models clearly shown that GHRH or NGF overexpression by anterior pituitary cells induced development of pituitary hyperplasia and adenomas particularly GH-oma and prolactinoma. Taken together, we hypothesize that the pituitary GHRH could serve not only as a modulator of hormone secretion but as a paracrine or autocrine regulator of anterior pituitary cell proliferation and differentiation. Interestingly enough, the expression of Pit-1 homeobox gene (the POU class transcription factor) was confined to somatotrophs, lactotrophs and somatolactotrophs in which GHRH receptors are expressed commonly. Concerning the mechanism of somatolactotroph and lactotroph differentiation in the anterior pituitary, we have focused following two possibilities; (1) changes in the relative levels or interactions of both hypothalamic and intrapituitary factors such as dopamine, VIP, somatostatin, NGF and GHRH; (2) alterations of GHRH-GHRH receptor signaling and Pit-1 activity may be the cause of lactotroph differentiation or pituitary hyperplasia and adenoma formation. Extensive further studies will be necessary to solve these complicated questions.

• Imaging Science in Dentistry
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• v.35 no.4
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• pp.191-198
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• 2005

Purpose: To characterize the effects of 2-deoxy-D-glucose (2DG) and quercetin (QCT) on cytokine secretion of IL-6, $TGF-\beta$ and gene expression of Col I in irradiated MC3T3-E1 cells Materials and Methods: The MC3T3-El cells were cultured in an a-MEM supplemented with 5mM 2DG or 10mM QCT and then the cells were incubated 12h before irradiation with 2, 4, 6, and 8Gy X-ray using a linear accelerator delivered at a dose rate of 1.5Gy/min. Level of IL-6 and $TGF-\beta$ was determined by ELISA. Also expression of Col I was examined by RT-PCR. Results: In accordance with the radiation dose, the amount of $TGF-\beta$ was not different in RA + QCT, but it showed a peak value in control and RA + 2DG at 4Gy on the 3rd day. However, all groups showed a decreasing tendency dose-dependently in RA+QCT on the 7th day (p<0.01). In accordance with the radiation dose, the amount of IL-6 increased dose-dependently in all groups on the 3rd day. On the 7th and 21st day, all groups showed peak values at 4Gy. RA+QCT showed a slightly increased amount of IL-6 at 2Gy, but it showed a slightly decreased amount at 4, 6, and 8Gy. In accordance with the period of culture after irradiation, the expression of Col I increased dose-dependently in RA+QCT. Conclusion: The result showed that QCT acted as radiosensitizer in the secretion of $TGF-\beta$ and gene expression of Col I during differentiation in irradiated MC3T3-E1 cells at the cellular level.

• Molecular & Cellular Toxicology
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• v.2 no.4
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• pp.223-228
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• 2006

Several plant-derived cannabinoids and endogenous ligands for cannabinoid receptors such as 2-arachidonyl-glycerol have been known to inhibit interleukin-2 (IL-2) expression. In the present study, we utilized arachidonylethanolamide (AEA), a putative endogenous ligand for cannabinoid receptors, to determine whether AEA modulated the expression of IL-2. AEA inhibited phorbol 12-myristate 13-acetate (PMA) plus ionomycin (Io)-induced IL-2 protein secretion and mRNA expression in EL-4 mouse T-cells as determined by ELISA and RT-PCR, respectively. To further characterize the inhibitory mechanism of AEA at the transcriptional level, we performed promoter study for IL-2 gene in PMA/Io-stimulated EL-4 cells. AEA decreased the transcriptional activity of the nuclear factor of activated T-cells (NF-AT) as well as the IL-2 promoter activity. These results suggest that AEA suppresses IL-2 expression and that the inhibition is mediated, at least in part, through the down-regulation of NF-AT.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.26 no.1
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• pp.19-34
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• 2013

Objective : This study was performed to evaluate the effect of immune reaction inductive substances such as PMA, LPS, DPE, DNCB and WP, the whitman pigra extracting substance at simultaneously on the translocation of $NF{\kappa}B$ towards to the nucleus and the mRNA expression patterns of various cytokine genes in THP-1 cells, monocytes of human. Methods : To analyze the cytokine genes expressions, the RT-PCR method was used, and measuring TNF-${\alpha}$ that had been secreted during cell culture by the ELISA method. The morphological changes were observed during THP-1 cell by a scanning electron microscope and the quantitative distribution of $NF{\kappa}B$ in the cell that was analyzed through immunocytochemistry and a confocal microscopy. Results : WP showed different influences onto the mRNA expression patterns of cytokine genes with PMA, LPS. DPE and DNCB according to the types of immune inductive substances in the THP-1 cells. Upon treating PMA and DPE on the THP-1 cells at the same time or either additionally treating WP thereon, the movement of $NF{\kappa}B$ increase towards the nucleus from cell cytoplasm was able to be observed. The expressions of IL-$1{\alpha}$ and IFN-${\gamma}$ induced by PMA and PMA+DNCB were suppressed by WP while the expression of TGF-${\beta}$ was promoted. Regarding the secretion pattern of TNF-${\alpha}$ according to the treatment of PMA, its secretion amount was incredibly increased by concurrent treatment of WP, however, in case of co-treatment of WP with PMA and DNCB, it was found that the secretion amount of TNF-${\alpha}$ decreased. Conclusions : In this study, the WP extracting substance was confirmed that it had an influence on expression patterns of cytokine genes according to the actions of a variety kinds of immune reaction inductive substances treated on the THP-1 cells. Especially, WP co-treatment with PMA and DNCB was suppressed the expression of inflammatory cytokines, such as IL-$1{\alpha}$, IFN-${\gamma}$ and TNF-${\alpha}$.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.432-434
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• 1989

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.207.2-207
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• 2005

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1248-1254
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• 2007

The secretory overexpression of Clostridium thermocellum endoglucanase A gene (celA) was examined in Saccharomyces cerevisiae using Kluyveromyces marxianus exoinulinase (INU1) signal sequence and GAL10 promoter. The two plasmids, pYEG-CT1 with its own signal sequence, and pYInu-CT1 with INU1 signal sequence were introduced to S. cerevisiae SEY2102 and S. cerevisiae 2805 host strains, respectively, and then each transformant was selected on the synthetic defined media lacking uracil. The expression level and secretion efficiency of endoglucanase A was increased by $18{\sim}22%$ and 11%, respectively, by INU1 signal sequence over celA signal sequence. By considering the high level of expression (361 unit/I), plasmid stability (89%), and secretion efficiency (70%), S. cerevisiae 2805 harboring plasmid pYInu-CT1 was selected as the opti-mal host vector system for the production of cellulose-degrading enzyme and recombinant yeast probiotic. The total expression and secretion efficiency of endoglucanase A was 418 unit/l and 73%, respectively, in the batch fermentation of S. cerevisiae 2805/pYlnu-CT1 on galactose medium. The mo-lecular weight of secreted endoglucanase A was found to be greater than 100 kDa, presumably due to the N-linked glycosylation.

• Korean Journal of Veterinary Research
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• v.46 no.2
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• pp.97-105
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• 2006

All-trans retinoic acid (AtRA) induces growth inhibition and apoptosis in a variety of tumer cells, including MCF-7 cells. Insulin-like growth factors (IGFs) system has been reported to be associated with the development of cancer. Although MCF-7 cell with AtRA is to be the major stimulus for the cell growth and apoptosis, the mechanism of insulin-like growth factor-I (IGF-I)/insulin-like growth factor binding protein-3 (IGFBP-3) system remains to be elucidated. Thus, this study was conducted to the effect of AtRA on the gene expression and level of IGF-I and IGFBP-3. In addition, we investigated the involvement of PKC-${\delta}$ on the IGF-I and IGFBP-3 secretion in MCF-7 cell. AtRA(${\geq}10^{-7}M$) decreased the IGF-1 secretion and mRNA expressions, but increased IGFBP-3 secretion and mRNA expressions in MCF-7 cells. Especially, the treatment of AtRA at 72 hours caused a significant reduction in the IGF-I secretion and mRNA expressions but increment in IGFBP-3 secretion and mRNA expressions (p < 0.05). $10^{-7}M$ AtRA activated PKC-${\delta}$ that is one among PKC-$\iota$, ${\alpha}$, ${\lambda}$ and ${\delta}$ in MCF-7 cell. Rotllerin, a PKC-${\delta}$ inhibitor, blocked AtRA-induced inhibition of the IGF-I and mRNA expressions, and increase of lGFBP-3 and mRNA expressions in MCF-7 cell. Together, AtRA inhibited the IGF-I secretion and mRNA expressions, but increased IGFBP-3 secretion and mRNA expressions in MCF-7 cell. Furthermore, AtRA-induced alteration of IGF-I, IGFBP-3 secretion, and the gene expressions were mediated via PKC-${\delta}$ activity.