• The Korean Journal of Zoology
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• v.38 no.2
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• pp.238-247
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• 1995

쥐 뇌에·처 카드뮴에 대한 metallothionein-like protein(MTLP)의 유도 생성 능력을 알아보기 위하여 Stereotaxic Bpparatus를 이용하여 측뇌실에 카드뮴을 주사하여 다음과 같은 결과를 얻었다. 대조군과 생리식염수 처리군에서는 MTLP의 양적 변화가 없었고. 카드를 처리군은 대조군과 식염수 처리군에 비하여 MTLP가 2배 이상 유도되었다. MTLP의 분자량은 6.000-6,500 Oa 정도 였으며. 흡광도가 254 nm에서 높게 나타나고. 280 nm에서 낮게 나타나는 것으로 보아 thiol 함량이 높고 방향족 아미노산이 적은 단백질임을 알 수 있었다 또한 카드뮴 처리군에서는 MTLP 이외의 여러 종류의 protein-30. 64, 68, 80, 108 kDa-들이 유도되었다 이와 같은 결과로 카드뮴은 흰쥐 뇌에서도 MTLP의 유도 능력이 있음을 알 수 있었다.

• Ocean and Polar Research
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• v.23 no.4
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• pp.337-345
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• 2001

A Cd-binding protein was identified in the renal cytosol of the Antarctic clam Laternula elliptica which naturally contains high concentrations of Cd. The Cd-binding protein showed similar characteristics of metallothionein (MT) in molecular weight (about 10-12 kDa) and low spectral absorbance at 280 nm with relatively high absorbance at 254nm. Results of immuno-histochemical staining suggested that the MT-like Cd-binding protein was mainly located in the epithelial cells of the kidney. The MT-like protein was a major ligand of cytosolic Cd as shown in the elution profiles of chromatography and may play an important role in Cd sequestration and accumulation in L. elliptica kidney. A considerable amount of Cd was also found to be associated with particulate fraction, indicating the sequestration to particulate fraction is as important as binding to the cytosolic MT-like protein in Cd accumulation in the kidney.

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.288-292
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• 2005

A class I type 2 metallothionein (CMet2) cDNA from taproot of Codonopsis lanceolata was isolated and characterized. A CMet2 cDNA was 572 nucleotides long and had an open reading frame of 234 bp with a deduced amino acid sequence of 78 residues (pI = 4.99). The deduced amino acid sequence of CMet2 matched to the previously reported type 2 metallothionein-like protein genes and showed 74% identity with that of G. max (BAD18377) and C. arietinum (CAA65009). Expression of CMet2 by the RT-PCR was increased at 1 hr after cadmium and hydrogen peroxide treatment, respectively.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.348-358
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• 2007

Metallothionein, a cysteine-rich stress response protein that is naturally induced by a variety of immunologic stressors, has been shown to suppress autoimmune disorders through mechanisms not yet fully defined. In the present study, we examined the underlying mechanisms by which metallothionein might mediate such regulation of autoimmunity. $Na\ddot{i}ve\;CD4^+$ T cells from metallothionein-deficient mice differentiated to produce significantly less IL-10, $TGF-{\gamma}$, and repressor of GATA, but more $IFN-{\gamma}$ and T-bet, when compared with those from wild-type mice. The levels of IL-4 and GATA-3 production were not different between the two groups of mice. Conversely, treatment with exogenous metallothionein during the priming phase drove $na\ddot{i}ve$ wild-type $CD4^+\;T$ cells to differentiate into cells producing more IL-10 and $TGF-{\beta}$, but less $IFN-{\gamma}$ than untreated cells. Metallothionein-primed cells were hyporesponsive to restimulation, and suppressive to T cell proliferation in an IL-10-dependent manner. Lymphocytes from metallothionein-deficient mice displayed significantly elevated levels of AP-1 and JNK activities in response to stimulation compared with those from wild-type controls. Importantly, transgenic mice overexpressing metallothionein exhibited significantly reduced susceptibility to collagen-induced arthritis and enhanced IL-10 level in the serum, relative to their nontransgenic littermates. Taken together, these data suggest that metallothionein is able to promote the generation of IL-10-and $TGF-{\beta}$-producing type 1 regulatory T-like cells by downregulating JNK-dependent AP-1 activity. Thus, metallothionein may play an important role in the regulation of Th1-dependent autoimmune arthritis, and may represent both a potential target for therapeutic manipulation and a critical element in the diagnostic assessment of disease potential.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.231-237
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• 2001

A cDNA clone encoding metallothionein-like protein (CitMT45), which was reported by Moriguchi et al. (1998), was isolated from Citrus fruits cDNA library through differential screening. Our cDNA clone has longer 5'untranslated region, compared to it isolated by Moriguchi et al. (1998). RNA blot analysis showed that the mRNA was abundant in fleshes than peels, leaves, and flowers, as a single transcript. However, regardless of tissue types, the blots showed the similar expression patterns in the process of development with some different profile. These results suggest that CitMT45 may play important roles in the development and/or senescence of various tissues of Citrus. A genomic clone corresponding to CitMT45 was isolated and found to have three exons and two introns. A primer extension analysis suggested that the transcription of CitMT45 gene was started at three start sites with different degrees. The 5'-flanking region was shown to contain a putative metal regulatory element (MRE) and low- temperature responsive element which suggests the possibility of metal-and cold-regulated transcription, respectively.

• Ocean Science Journal
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• v.41 no.1
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• pp.43-51
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• 2006

Concentration and distribution of Fe, Zn, Cu, Cd, Mn, Pb, Ni among subcellular fractions (cellular membrane structures and cytosol) and Zn, Cu, Cd among cytoplasmic proteins in the kidney and digestive gland of mussel Modiolus modiolus living along a polymetallic concentration gradient were studied. It was found in the kidney of M. modiolus from contaminated sites that the Fe percent increased in the "membrane" fraction, whereas Zn, Pb, Ni and Mn percent increased in the cytosol compared to the kidney of the control mussel. Note kidney cytosol of M. modiolus from clean and contaminated sites sequestered major parts of Cu and Cd. In the digestive gland of M. modiolus from contaminated sites Fe, Zn, Cd, Mn, Ni percent increased in the "membrane" fraction, whereas Cu, Pb percent increased in the cytosol compared to digestive gland of control mussel. Gel-filtration chromatography shows kidney of M. modiolus contains increased metallothionein-like protein levels irrespective of ambient dissolved metal concentrations. It was shown that the metal detoxification system in the kidney and digestive gland of M. modiolus was efficient under extremely high ambient metal levels. However, under complex environmental contamination in the kidney of M. modiolus, the metal detoxification capacity of metallothionein-like proteins was damaged.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1286-1294
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• 2004

In a previous study by the current authors, hepatocellular carcinoma (HCC) was determined to be epidemiologically sex-dependent, and the incidence and multiplicity of HCC found to decrease in estradiol-3 benzoate (EB)-treated F344 rats. Therefore, to ascertain the anticancer mechanism of EB, a commercially available cDNA microarray, with a total of 14,815 cDNA rat gene clones, was used to determine the differentially expressed genes in nontreated livers, EB-treated livers, and diethynitrosolamine (DEN)-induced HCC. In the sequenced experiment, a total of 85 genes were differentially expressed at either two or more times the rate of the normal expression, where 33 genes were downregulated by EB, and 52 genes upregulated. Candidate genes were selected according to significant changes observed in the mRNA expression in the EB-treated livers compared with the nontreated livers, then these genes were filtered according to their different expression patterns in the DEN-induced tumors compared to the estrogen-treated livers. To confirm the microarray data, a real-time PCR analysis was performed for ten selected genes: the H-ras revertant protein 107 (H­rev107), insulin-like growth factor binding protein (lOFBP), parathyroid hormone receptor (PI'HR), SH3 domain binding protein (SH3BP), metallothionein, src-suppressed C-kinase substrate (SSeCK) gene, phosphodiesterase I, CD44, epithelial membrane protein 3 (EMP3), and estrogen receptor a (ERa). The SSeCK and phosphodiesterase I genes were both upregulated in the DEN-induced hepatocarcinomas, yet their possible carcinogenic functions remain unknown. Meanwhile, the other genes were downregulated, including the genes related to growth regulation (IOFBP, H-revI07, ER$\alpha$), adipogenesis inhibition (PTHR), and tumor suppression (metallothionein).

• Molecular & Cellular Toxicology
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• v.2 no.1
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• pp.54-59
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• 2006

The toxicity of cadmium on Caenorhabditis elegans was investigated to identify sensitive biomarkers for environmental monitoring and risk assessment. Stress-related gene expression were estimated as toxic endpoints Cadmium exposure led to an increase in the expression of most of the genes tested. The degree of increase was more significant in heat shock protein-16.1, metallothionein-2, cytochrome p450 family protein 35A2, glutathione S-transferase-4, superoxide dismutase-1, catalase-2, C. elegans p53-like protein-1, and apoptosis enhancer-1 than in other genes. The overall results indicate that the stress-related gene expressions of C. elegans have considerable potential as sensitive biomarkers for cadmium toxicity monitoring and risk assessment.

• Molecules and Cells
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• v.43 no.4
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• pp.323-330
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• 2020

Epigenetic events like DNA methylation and histone modification can alter heritable phenotypes. Zinc is required for the activity of various epigenetic enzymes, such as DNA methyltransferases (DNMTs), histone acetyltransferases (HATs), histone deacetylases (HDACs), and histone demethylases, which possess several zinc binding sites. Thus, the dysregulation of zinc homeostasis can lead to epigenetic alterations. Zinc homeostasis is regulated by Zinc Transporters (ZnTs), Zrt- and Irt-like proteins (ZIPs), and the zinc storage protein metallothionein (MT). Recent advances revealed that ZIPs modulate epigenetics. ZIP10 deficiency was found to result in reduced HATs, confirming its involvement in histone acetylation for rigid skin barrier formation. ZIP13 deficiency, which is associated with Spondylocheirodysplastic Ehlers-Danlos syndrome (SCD-EDS), increases DNMT activity, leading to dysgenesis of dermis via improper gene expressions. However, the precise molecular mechanisms remain to be elucidated. Future molecular studies investigating the involvement of zinc and its transporters in epigenetics are warranted.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.440-446
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• 2006

To investigate flowering related genes in winter-type oilseed rape (Brassica napus L. cv. Tammi), differentially expressed genes were isolated from leaves of the plant after low temperature treatment which is requirements for floral induction. As a result of suppression subtractive hybridization (SSH), 288 clones were randomly selected from SSH library. Using reverse Northern blot analysis, 150 of 288 clones were identified to be differentially expressed. Out of these 150 clones, 45 clones showed very high identities with the known genes. Four clones showed very high identities over 90% with metallothionein-like gene that is related to flowering-induced genes. Of these 4 clones, the cDNA clone, rfs-13, revealed high identity with meotallothionein-like protein in Arabidopsis thaliana (98%) and Brassica compestris (89%). Furthermore, gene expressed in immature flower stages was confirmed by Northern blot analysis.