• BMB Reports
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• v.34 no.5
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• pp.395-401
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• 2001

Schizosaccharomyces pombe gene encoding redox enzymes, such as thioltransferase (TTase) and thioredoxin (TRX), were previously cloned and induced by oxidative stress. In this investigation, their expressions were examined using $\beta$-galactosidase fusion plasmids. The expression of the two cloned genes appeared to be growth-dependent. The synthesis of $\beta$-galactosidase from the TTase-lacZ fusion was increased in the medium with the low glucose level, whereas it was significantly decreased in the medium without glucose or with galactose. It was also decreased in the nitrogen-limited medium. The synthesis of galactosidase from the TRX-lacZ fusion was unaffected by galactose or low glucose. However, it was lowered the absence of glucose. The synthesis of $\beta$-galactosidase from the TTase-lacZ fusion was shown to be enhanced in a higher medium pH. Our findings indicate that S. pombe TTase and TRX genes may be regulated by carbon and nitrogen sources, as well as medium pH.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.125-128
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• 2007

• Molecules and Cells
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• v.41 no.2
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• pp.140-149
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• 2018

The $TIS21^{/BTG2/PC3}$ gene belongs to the antiproliferative gene (APRO) family and exhibits tumor suppressive activity. However, here we report that TIS21 controls lipid metabolism, rather than cell proliferation, under fasting condition. Using microarray analysis, whole gene expression changes were investigated in liver of TIS21 knockout (TIS21-KO) mice after 20 h fasting and compared with wild type (WT). Peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) target gene expression was almost absent in contrast to increased lipid synthesis in the TIS21-KO mice compared to WT mice. Immunohistochemistry with hematoxylin and eosin staining revealed that lipid deposition was focal in the TIS21-KO liver as opposed to the diffuse and homogeneous pattern in the WT liver after 24 h starvation. In addition, cathepsin E expression was over 10 times higher in the TIS21-KO liver than that in the WT, as opposed to the significant reduction of thioltransferase in both adult and fetal livers. At present, we cannot account for the role of cathepsin E. However, downregulation of glutaredoxin 2 thioltransferase expression might affect hypoxic damage in the TIS21-KO liver. We suggest that the $TIS21^{/BTG2}$ gene might be essential to maintain energy metabolism and reducing power in the liver under fasting condition.

• BMB Reports
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• v.31 no.6
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• pp.554-559
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• 1998

Activities of glutathione- and thioredoxin-related enzymes and phenylpropanoid-synthesizing enzymes were measured and compared in the developing leaves of Arabidopsis thaliana. Phenylalanine ammonia-lyase activity is maximal in the leaves of 2-wk-grown Arabidopsis. Tyrosine ammonia-lyase activity is maximal in the leaves of 3-wk-grown and 4-wk-grown Arabidopsis. Activity of thioitransferase, an enzyme involved in the reduction of various disulfide compounds, is higher in younger leaves than in older ones. A similar pattern was obtained in the activity of thioredoxin, a small protein known as a cofactor of ribonucleotide reductase and a regulator of photosynthesis. Activity of glutathione reductase is also higher in the younger leaves. Malate debydrogenase activity remains relatively constant during the development of Arabidopsis leaves. The results offer preliminary information for further approach to elucidate the mechanism of growth-dependent variations of these enzymes.

• BMB Reports
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• v.33 no.2
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• pp.179-183
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• 2000

The glutathione S-transferase (GST) activities of S-type and L-type thioltransferases (TTases), which are purified from the seeds and leaves of Arabidopsis thaliana, respectively, were identified and compared. The S-type and L-type TTases showed $K_m$ values of 9.72 mM and 3.18mM on 1-chloro-2,4-dinitrobenzene (CDNB), respectively, indicating the L-type TTase has higher affinity for CDNB. The GST activity of the L-type TTase was rapidly inactivated after being heated at $70^{\circ}C$ or higher. The GST activity of the S-type TTase remains active in a range of $30-90^{\circ}C$. $Hg^{2+}$ inhibited the GST activity of the S-type TTase, whereas $Ca^{2+}$ and $Cd^{2+}$ inhibited the GST activity of the L-type TTase. Our results suggest that the GST activities of two TTases of Arabidopsis thaliana may have different catalytic mechanisms. The importance of the co-existence of TTAse and GST activities in one protein remains to be elucidated.

• Molecules and Cells
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• v.25 no.3
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• pp.332-346
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• 2008

S-glutathionylation is a reversible post-translational modification that continues to gain eminence as a redox regulatory mechanism of protein activity and associated cellular functions. Many diverse cellular proteins such as transcription factors, adhesion molecules, enzymes, and cytokines are reported to undergo glutathionylation, although the functional impact has been less well characterized. De-glutathionylation is catalyzed specifically and efficiently by glutaredoxin (GRx, aka thioltransferase), and facile reversibility is critical in determining the physiological relevance of glutathionylation as a means of protein regulation. Thus, studies with cohesive themes addressing both the glutathionylation of proteins and the corresponding impact of GRx are especially useful in advancing understanding. Reactive oxygen species (ROS) and redox regulation are well accepted as playing a role in inflammatory processes, such as leukostasis and the destruction of foreign particles by macrophages. We discuss in this review the current implications of GRx and/or glutathionylation in the inflammatory response and in diseases associated with chronic inflammation, namely diabetes, atherosclerosis, inflammatory lung disease, cancer, and Alzheimer's disease, and in viral infections.