• Nutrition Research and Practice
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• v.3 no.3
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• pp.192-199
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• 2009

Cadmium intoxication has been associated with the dysregulation of iron homeostasis. In the present study, we investigated the effect of cadmium on the expression of ferroportin 1 (FPN1), an important iron transporter protein that is involved in iron release from macrophages. When we incubated cadmium with J774 mouse macrophage cells, FPN1 mRNA levels were significantly increased in a dose- and time-dependent manner. Furthermore, the cadmium-induced FPN1 mRNA expression was associated with increased levels of FPN1 protein. On the other hand, cadmium-mediated FPN1 mRNA induction in J774 cells was completely blocked when cells were co-treated with a transcription inhibitor, acitomycin D. Also, cadmium directly stimulated the activity of the FPN1-promoter driven luciferase reporter, suggesting that the cadmium up-regulates FPN1 gene expression in a transcription-dependent manner. Finally, cadmium exposure to J774 macrophages increased intracellular reactive oxygen species (ROS) levels by ${\sim}2$-fold, compared to untreated controls. When J774 cells were co-treated with antioxidant N-acetylcystein, the cadmium-induced FPN1 mRNA induction was significantly attenuated. In summary, the results of this study clearly demonstrated that cadmium increased FPN1 expression in macrophages through a mechanism that involves ROS production, and suggests another important interaction between iron and cadmium metabolism.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.485-489
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• 2004

Melanin pigmentation in human skin is a major defensive mechanism against ultraviolet light of the sun. Tyrosinase plays a key role in the biosynthesis of melanin. This is why many researches have been focused on regulations in controlling the epidermal melanization. We found that extract of Canavalia lineata inhibits mushroom tyrosinase activity, dopa oxidase activity, and melanin synthesis in B16F10 melanoma cells. To elucidate mRNA level reverse transcription polymerase chain reaction (RT-PCR) technique was used. It was revealed that A subfraction of $CHCI_3$ extract of Canavalia lineara reduced the tyrosinase mRNA expression of B16F10 melanoma cells by reverse transcription polymerase chain reaction (RT-PCR) technique.

• BMB Reports
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• v.50 no.4
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• pp.162-163
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• 2017

RNA polymerase II-interacting the Set2 methyltransferase co-transcriptionally methylates histone H3 at lysine 36 within the body of genes. This modification facilitates histone deacetylation by Rpd3S HDAC in 3' transcribed regions to suppress cryptic initiation and slow elongation. Although this pathway is important for global deacetylation, no strong effects have been seen on genome-wide transcription under optimized laboratory conditions. In contrast, this pathway slows the kinetics of mRNA induction when target genes are induced upon environmental changes. Interestingly, a majority of Set2-repressed genes are overlapped by a lncRNA transcription that targets H3K36 methylation and deacetylation by Rpd3S HDAC to mRNA promoters. Furthermore, this pathway delays the induction of many cryptic transcripts upon environmental changes. Therefore, the Set2-Rpd3S HDAC pathway functions to fine-tune expression dynamics of mRNAs and ncRNAs.

• Korea Journal of Cosmetic Science
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• v.1 no.1
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• pp.31-43
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• 2019

Melanosomes are specific melanin-containing intracellular organelles of epidermal melanocytes. In epidermal melanocytes, there are three kinds of key player proteins. Rab27a, melanophilin or Slac2-a and Myosin 5a form a tripartite complex connects the melanosome. Mature melanosomes make movements through the tripartite protein complex along actin filaments.In this study, we found that the haplamine (6-Methoxyflindersine) induced melanosome aggregation around the nucleus in epidermal melanocyte. In an attempt to elucidate the inhibitory effect of haplamine on melanosome transport, effect of haplamineon the expression level of Rab27a, melanophilin and Myosin 5a was measured. The results indicated that haplamine up to 5��M effectively suppressed mRNA and protein expression level of melanophilin.To determine the upstream regulator of melanophilin regulated by haplamine, we checked the level of MITF, c-JUN and USF1. Those are possible transcription factor of melanophilin. Among them,treatment of USF1 siRNA decreased mRNA and protein expression level of USF1 as well as melanophilin. Also, treatment of haplamine decreased mRNA and protein expression level of melanophilin as well as USF1 in a dose-dependent manner. Consequently, we found the inhibitory effect of haplamine on melanosome transport in melan-a melanocyte. Treatment of haplamine reduced melanophilin expression level which is a key protein of melanosome transport. We identified that USF1 could be a major transcription factor of melanophilin regulated by haplamine.

• 한국전자현미경학회:학술대회논문집
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• 1996.05a
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• pp.22-22
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• 1996

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.22-23
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• 2007

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1187-1193
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• 2015

This study determined the effects of dietary restriction on growth and the expression of lipid metabolism and growth hormone signaling genes in the longissimus dorsi muscle (LM) of Korean cattle. Thirty-one Korean cattle steers (average age 10.5 months) were allocated to normal (N; n = 16) or dietary restriction (DR; n = 15) groups. The feeding trial consisted of two stages: for the 8-month growing period, the DR group was fed 80% of the food intake of the normal diet, and for the 6-month growth-finishing period, the DR group was fed a DR total mixed ration with 78.4% of the crude protein and 64% of the net energy for gain of the normal diet. The LM was biopsied 5 months (period 1 [P1] at 15.5 months of age) and 14 months (period 2 [P2] at 24.5 months of age) after the start of feeding. The mRNA levels were determined using real-time polymerase chain reaction. Body weight, daily feed intake, average daily gain, and feed efficiency were lower in the DR group compared with the normal group at both P1 and P2. At P1, the lipogenic fatty acid synthase (FASN) mRNA levels were lower (p<0.05) in the DR group compared with the normal group. The DR group tended (p = 0.06) to have higher of levels of growth hormone receptor (GHR) mRNA than the normal group. At P2, the DR group tended to have lower (p = 0.06) androgen receptor (AR) mRNA levels than the normal group. In conclusion, our results demonstrate that dietary restriction partially decreases the transcription of lipogenic FASN and growth hormone signaling AR genes, but increases transcription of the GHR gene. These changes in gene transcription might affect body fat accumulation and the growth of the animals.

• BMB Reports
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• v.53 no.11
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• pp.605-610
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• 2020

Skeletal myogenesis is a complex process that is finely regulated by myogenic transcription factors. Recent studies have shown that saturated fatty acids (SFA) can suppress the activation of myogenic transcription factors and impair the myogenic differentiation of progenitor cells. Despite the increasing evidence of the roles of miRNAs in myogenesis, the targets and myogenic regulatory mechanisms of miRNAs are largely unknown, particularly when myogenesis is dysregulated by SFA deposition. This study examined the implications of SFA-induced miR-183-5p on the myogenic differentiation in C2C12 myoblasts. Long-chain SFA palmitic acid (PA) drastically reduced myogenic transcription factors, such as myoblast determination protein (MyoD), myogenin (MyoG), and myocyte enhancer factor 2C (MEF2C), and inhibited FHL1 expression and myogenic differentiation of C2C12 myoblasts, accompanied by the induction of miR-183-5p. The knockdown of FHL1 by siRNA inhibited myogenic differentiation of myoblasts. Interestingly, miR-183-5p inversely regulated the expression of FHL1, a crucial regulator of skeletal myogenesis, by targeting the 3'UTR of FHL1 mRNA. Furthermore, the transfection of miR-183-5p mimic suppressed the expression of MyoD, MyoG, MEF2C, and MyHC, and impaired the differentiation and myotube formation of myoblasts. Overall, this study highlights the role of miR-183-5p in myogenic differentiation through FHL1 repression and suggests a novel miRNA-mediated mechanism for myogenesis in a background of obesity.

• Journal of Microbiology
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• v.34 no.1
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• pp.54-60
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• 1996

Taking advantage of the heat inducible HSP82 gene in yeast, chromatin structure after transcription cessation was investigated. Alteration of chromating conformation within the HSP82 gene transcription unit into an active state has been shown to correlate with its transcriptional induction. It was thus of interest to examine whether the active chromatin state within the HSP82 mRNA analysis, the gene ceased its transcription within a few hours of cultivation at a normal condition after heat induction. In this condition, an active chromatin conformation in the HSP82 gene body was changed into an inactie state which was revealed by DNase I resistance and by typical nucleosomal cutting periodicity in the corresponding chromatin. These results thus ruled out the possibility of a long-term maintenance of the DNase I sensitive chromatin after transcription cessation. DNA replication may be a critical event for the chromatin reprogramming.

• BMB Reports
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• v.28 no.1
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• pp.27-32
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• 1995

Polyclonal antibodies against human DNA-dependent RNA polymerase II (HPP II) were generated from chicken egg yolk after immunization with RNA polymerase II as an antigen. The antibodies from egg yolk (IgY) were purified and characterized. IgY showed a specificity against DNA-dependent RNA polymerase II, and was a polyclonal antibody against 12 subunits of polymerase II. An amount of 0.35 mg of IgY was obtained freman HPP II-Sepharose affinity column using 10 eggs from a chicken immunized against RNA polymerase II as an antigen. These antibodies can be used for isolating the genes for RNA polymerase II components, and for in vitro transcription assays using HP-RNA polymerase II.