• Journal of Life Science
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• v.12 no.2
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• pp.47-52
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• 2002

Saccharomyces cerevisiae KNU5377 (KNU5377) and S. cerevisiae ATCC24858 (ATCC24858) were exposed to $H_2SO_4$ as a stress, which was added at various concentrations to a YPD media. The growth of KNU5377 was reduced to approximately 60% in the YPD media containing 40 nm sulfuric acid when compared to the non-stressed condition. When their growth was monitored during an overnight culture, two strains, KNU5377 and ATCC24858, could not grow when exposed to over 50 mM of sulfuric acid. After a short exposure to this acid for 1 h, KNU5377 exhibited stronger resistance against $H_2SO_4$ than ATCC24858. The neutral trehalase activity of KNU5377 unchanged despite under various concentrations of $H_2SO_4$. In contrast, It at of ATCC24858 was much low at higher $H_2SO_4$concentrations. Trehalose, a non-reducing disaccharide, was maximally accumulated after a short exposure to 60 nm $H_2SO_4$ for KNU5377, but it was reduced under more severe stressful conditions. These results suggest that KNU5377 should modulate the trehalose concentrations under the severe stress condition of high sulfuric acid concentrations. The most highly induced protein in the KNU5377 exposed to sulfuric acid was found to be an approximately 23 kDa protein, which was revealed to be the 605 large subunit ribosomal protein, Ll3 by FASTA search results.

• Toxicological Research
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• v.17
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• pp.59-69
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• 2001

Arsenic exposure is associated with several human diseases, including cancers, atherosclerosis, hypertension, and cerebrovascular diseases. In cultured cells, arsenite, an inorganic arsenic com-pound, was demonstrated to interfere with many physiological functions, such as enhancement of oxidative stress, delay of cell cycle progression, and induction of structural and numerical changes of chromosomes. The objective of this study is to investigate the effects of arsenic exposure on gene expression profiles by colorimetric cDNA microarray technique. HFW (normal human diploid skin fibroblasts), CL3 (human lung adenocarcinoma cell line), and HaCaT (immortalized human keratinocyte cell line) were treated with 5 $\mu\textrm{M}$ or 10 $\mu\textrm{M}$ sodium arsenite for 6 or 16 h, respectively. By a dual-color detection system, the expression profile of arsenite-treated cultures was compared to that of control cultures. Several genes expressed differentially were identified on the microarray membranes. For example, MDM2, SWI/SNF, ubiquitin specific protease 4, MAP3K11, RecQ protein-like 5, and Ribosomal protein Ll0a were consistently induced in all three cell types by arsenite, whereas prohibitin, cyclin D1, nucleolar protein 1, PCNA, Nm23, and immediate early protein (ETR101) were apparently inhibited. The present results suggest that arsenite insults altered the expression of several genes participating in cellular responses to DNA damage, stress, transcription, and cell cycle arrest.