• Journal of Microbiology
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• v.42 no.3
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• pp.233-238
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• 2004

Transcriptional regulation of the Schizosaccharomyces pombe y-glutamylcysteine synthetase (GCS) gene was examined using the two GCS-lacZ fusion plasmids pUGCS101 and pUGCS102, which harbor 607 bp and 447 bp upstream regions, respectively. The negatively-acting sequence was located in the -607 - -447 bp upstream region of the GCS gene. The upstream sequence responsible for induction by menadione(MD) and L-buthionine-(S, R)-sulfoximine (BSO) resides in the -607 - -447 bp region, whereas the sequence which codes for nitric oxide induction is located within the -447 bp region, measured from the translational initiation point. Carbon source-dependent regulation of the GCS gene appeared to be dependent on the nucleotide sequence within -447 bp region. The transcription factor Papl is involved in the induction of the GCS gene by MD and BSO, but not by nitric oxide. Induction of the GCS gene occurring due to low glucose concentration does not depend on the presence of Pap1. These data imply that induction by MD and BSO may be mediated by the Pap1 binding site, probably located in the -607 - -447 region, and also that the nitric oxide-mediated regulation of the S. pombe GCS gene may share a similar mechanism with its carbon-dependent induction.

• BMB Reports
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• v.30 no.3
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• pp.188-193
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• 1997

Membrane lipid peroxidation processes yield products that may react with DNA to cause mutations. Lipid hydroperoxides from linoleic acid in the presence of transition metal ions caused strand breaks in plasmid DNA. DNA damage induced by reactive aldehydes known to be produced by decomposition of lipid hydroperoxides, such as 4-hydroxynonenal or rnalondialdehyde, was repaired by endonucleases and exonuclease III which resulted in the increase of single strand breaks in DNA. Lipid hydroperoxides as well as malondialdehyde and 4-hydroxynonenal also caused mutations in the pUC18 lacZ' gene when measured as a loss of ${\alpha}-cornplementation$. In conclusion. the lipid peroxidation could be an important intermediary event in DNA damage and mutation by oxidative stress.

• Environmental Mutagens and Carcinogens
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• v.10 no.1
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• pp.1-10
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• 1990

The regulation of DNA repair genes expression was investigated using fused genes, in which the promoter of repair genes was hybridized with the lacZ structural gene. The activities of beta-galactosidase expressed from the fused gense were highly increased when the host cells were exposed to methylating agents, such as methyl methansulfonate (MMS), N-methyl-N'-nitro-nitrosoguanidine (MNNG) and methyl nitrosourea (MNU). On the other hand, the enzyme activities from the fused genes were not induced when the cells were treated with ethylating or nonalkylating agents, such as ethyl methansulfonate (EMS), 4-nitroquinoline-1-oxide (4NQO), Bleomycin, and Benzo(a)pyrene (BP).

• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.9-20
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• 1996

Genotoxicity/mutagenicity of organic chemicals in industrial wastewater was investigated using umu-test with a Salmonella typhimurium TA1535 strain. The tester strain was derived by introducing plasmid pSK 1002, which carried a umu C - lac Z fusion gene into S typhimurium TA1535, and tester strain in the presence microsomal activation proved to be the more sensitive maker of genotoxicity. Genotoxic responses were observed in concentrated with a blue-rayon column, from 14 plants tested. The results were as follow; 1. Genotoxic responses were observed in concentrated from nine plants(64.3%) tested. 2. The results show that genotoxic activity was particulary high in the untreated wastewaters and decreased in the treated wastewaters(35.7%) 3. No significant correlation was found between genotoxicity and water ollution indicators, such as COD and BOD.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.4
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• pp.581-589
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• 1993

A plasmid vector, $RSVLTR/{\beta}G2$, containing lacZ gene under the control of the RSVLTR promoter were transfected into chicken embryo fibroblasts by three different transfection methods. Calcium phosphate, lipsome and DEAE-dextran techniques were applied for transfection of chicken cells. A histochemical assay with X-gal was used as a simple method for screening transfected cells. Plasmid $RSVLTR/{\beta}G2$ was expressed proficiently in the chicken embryo fibroblast. Calcium phosphate-DNA precipitate transfection resulted in the highest efficiency for transient expression of $RSVLTR/{\beta}G2$. Transfected cells formed colonies on the 9th day of incubation indicating stable transformation of the inserted plasmid.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1527-1535
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• 2009

Polyphosphate (polyP) plays diverse physiological functions in prokaryotes and eukaryotes, but most of their detailed mechanisms are still obscure. Here, we show that deletion of polyphosphate kinase (PPK), the principal enzyme responsible for synthesis of polyP, resulted in augmented expression of cAMP receptor protein (CRP) and rpoS and lowered $H_2O_2$ sensitivity in Salmonella Typhimurium ATCC14028. The binding of cAMP-CRP complex to rpoS promoter and further stimulation of its transcription were proved through electrophoretic mobility shift assay, lacZ fusion, and exogenous cAMP addition, respectively. The rpoS expression increased in cpdA (cAMP phosphodiesterase coding gene) mutant, further suggesting that cAMP-CRP upregulated rpoS expression. These results demonstrate that PPK affects oxidative stress response by modulating crp and rpoS expression in S. Typhimurium.

• BMB Reports
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• v.45 no.10
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• pp.577-582
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• 2012

single-minded (sim) is a master regulatory gene that directs differentiation in the central nervous system during Drosophila embryogenesis. Recent identification of the mesectoderm enhancer (MSE) of sim has led to the hypothesis that two Snail (Sna)-binding sites in the MSE may repress sim expression in the presumptive mesoderm. We provide evidence here that three Sna-binding sites proximal to the sim promoter, but not those of the MSE, are responsible for the mesodermal repression of sim in vivo. Using transgenic embryos injected with lacZ transgenes, we showed that sim repression in the mesoderm requires the three promoter-proximal Sna-binding sites. These results suggest that Sna represses the mesectodermal expression of sim by directly repressing the nearby promoter, and not by quenching adjacent transcriptional activators in the MSE. These data also showed how the MSE, lacking the three proximal Sna-binding sites, reproduced the endogenous pattern of sim expression in transgenic embryos.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.64-64
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• 2001

Escherichia coli has developed soxRS regulon to defend against toxicity of superoxide radical. SoxR, superoxide sensor, is oxidized by superoxide-generating agents or nitric oxide and oxidized SoxR activates the transcription of soxS gene. In order to find out the trans-acting factors regulating SoxR activity in vivo, soxS：：lacZ single copy operon fusion construct was prepared and random Tn10 insertional mutatons were performed.(omitted)

• Korean Journal of Animal Reproduction
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• v.27 no.1
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• pp.15-23
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• 2003

Lactadherin (formerly known as BA46), a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and breast carcinomas and may prevent symptomatic rotavirus infections. In this study, under the control of tissue specific and hormonal inducible mouse whey acidic protein (WAP) promote., the expression pattern of lactadherin (Ltd) in lactogenic hormone-dependent mouse mammary epithelial cell line HC11 were tested. pLNWLtd construct containing 2.4 kilobases of the WAP promoter and 1.5 kilobases of human lactadherin gene was stably transfered into HC11 cells using retroviral vector system. Integration and expression level of the transgene was estimated using PCR and RT-PCR, respectively. Prominent induction of Ltd gene under the WAP promoter was accomplished in the presence of insulin, hydrocortisone and prolactin. Compared to the control (cells cultured with insulin alone), however we observed that the WAP promoter was leaky. These data indicate that luther studies are needed in finding an appropriate promoter other than WAP promoter because of its leakiness.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.46-51
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• 1995

In order to develope baculovirus expression vector system, we constructed new transfer vector of nuclear polyhedrosis virus of the silkworm, Bombyx mori. The promoter region containing only adenine of translation start codon of polyhedrin gene was cloned by polymerase chain reaction technique. And the 5' and 3' leader regions of polyhedrin gene was sequentially cloned. The polyhedrin coding gene was deleted from the ＋2 to the ＋597 position. As the result, we constructed new transfer vector which has EcoRI, SacI and KpnI sites for the cloning sites of foreign gene. New transfer vector was named as pBmKSKl. Escherichia coli $\beta$-galactosidase gene as foreign gene was inserted into pBmKSKl, under the control of the polyhedrin promoter and expressed in B. mori cells. The result showed that the new transfer vector pBmKSK1 is functional.