• Journal of Microbiology
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• v.34 no.4
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• pp.355-362
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• 1996

Complementation cloning of the argC, E, B, D, F, and G genes in Corynebacterium glutamicum was done by transforming the genomic DNA library into the corresponding arginine auxotrophs fo Escherichia coli. Recombinant plasmids containing 6.7 kb and 4.8kb fragments complementing the E. coli argB mutant were also able to complement the E. coli argC, E, A, D, and F mutants, indicating the clustered organization of the arginine biosynthetic genes within the cloned DNA fragments. The insert DNA fragments in the recombinant plasmids, named pRB1 AND pRB2, were physically mapped with several restriction enzymes. By further subcloning the entire DNA fragment containing the functions and by complementation analysis, we located the arg genes in the order of ACEBDF on the restriction map. We also determined the DNA nucleotide sequence of the fragment and report here the sequence of the argB gene. When compared to that with the mutant strain, higher enzyme activity of N-acetylglutamate kinase was detected in the extract of the mutant carrying the plasmid containing the putative argB gene, indicating that the plasmid contains a functional argB gene. Deduced amino acid sequence of the argB gene shows 45%, 38%, and 25% identity to that from Bacillus strearothermophilus, Bacillus substilus, and E. coli respectively. Our long term goal is genetically engineering C. glutamicum which produces more arginine than a wild type strain does.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.206-209
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• 2001

Recombinant human GM -CSF was expressed and secreted from transgenic rice cell suspension cultures in its biologically active form. This was accomplished by transforming rice callus tissues with an expression vector, pMYN44. containing the hGM -CSF cDNA. Regulated expression and secretion of hGM -CSF from this vector achieved using the promoter, signal peptide, and terminator from a rice alfa-amylase gene Amy3D. The Amy3D gene is expressed in response to sugar deprivation. The recombinant hGM -CSF was expressed from the transgenic rice cell culture on the sugar-free medium as a yield of about 110 mg/L in the culture filtrate, which was determined by ELISA. Biological activity of hGM-CSF was confirmed by measuring the proliferation of the hGM -CSF dependent TF -1 cells.(This work was supported by a grant from the NRL program of the Korean Ministry of Science and Technology. Shin, Y.- J.. Lee. J.-H and Kwon, T.-H. have been supported by BK21 program from the Korean Ministry of Education)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3681-3685
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• 2012

Background: In breast cancer, estrogen receptors have been demonstrated to interact with transcription factors to regulate target gene expression. However, high-throughput identification of the transcription regulation relationship between transcription factors and their target genes in response to estradiol is still in its infancy. Purpose: Thus, the objective of our study was to interpret the transcription regulation network of MCF7 breast cancer cells exposed to estradiol. Methods: In this work, GSE11352 microarray data were used to identify differentially expressed genes (DEGs). Results: Our results showed that the MYB (v-myb myeloblastosis viral oncogene homolog [avian]), PGR (progesterone receptor), and MYC (v-myc myelocytomatosis viral oncogene homolog [avian]) were hub nodes in our transcriptome network, which may interact with ER and, in turn, regulate target gene expression. MYB can up-regulate MCM3 (minichromosome maintenance 3) and MCM7 expression; PGR can suppress BCL2 (B-cell lymphoma 2) expression; MYC can inhibit TGFB2 (transforming growth factor, beta 2) expression. These genes are associated with breast cancer progression via cell cycling and the $TGF{\beta}$ signaling pathway. Conclusion: Analysis of transcriptional regulation may provide a better understanding of molecular mechanisms and clues to potential therapeutic targets in the treatment of breast cancer.

• Fisheries and Aquatic Sciences
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• v.10 no.2
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• pp.60-67
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• 2007

Myostatin (MSTN; also known as GDF8) is a member of the transforming growth factor ${\beta}-superfamily$ of proteins. MSTN negatively regulates mammalian skeletal muscle growth and development by inhibiting myoblast proliferation. Mice and cattle possessing mutant MSTN alleles display a 'double muscling' phenotype characterized by extreme skeletal muscle hypertrophy and/or hyperplasia. We isolated the full-length cDNA of a novel MSTN gene from S. schlegeli muscle tissue and examined its expression pattern in various tissues. The full-length gene (GenBank DQ423474) consists of 1941bp with an open reading frame of 1134 bp, encoding 377 amino acids that show 62-92% amino acid similarity to other vertebrate MSTNs. The predicted protein contains a conserved proteolytic cleavage site (RXRR) and nine conserved cysteine residues at the C terminus. RT-PCR revealed that the unprocessed and prodomain myostatin mRNAs were predominantly present in muscle, with limited expression in other tissues. However, the mature myostatin mRNA was highly expressed in brain and muscle, intermediately expressed in the gills, intestine, heart, and kidney, and weakly expressed in the liver and spleen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.307-313
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• 2001

Iron excess is known to affect long-term iron accumulation and tissue change such as fibrosis in liver. To determine the changes of expression level of genes associated with fibrosis by short-term iron exposure, we measured liver mRNA levels by reverse transcription polymerase chain reaction (RT-PCR) in rats fed dietary carbonyl iron (3%, wt/wt) for 9 weeks. The results showed that the expression of the collagen (I, III) and transforming growth factor (TGF)-$\beta$I mRNAs was enhanced in high-dose iron treated rat, compared to normal-dose iron treated rat. An electron microscopy study revealed that excess iron caused increase of collagen fibrils in liver. The cell shapes and compositions of hepatocytes and extracellular matrix(ECM) in liver were changed by the iron-treatment. Also, necrosised hepatocytes were broadly seen in ECM. Taken together, we suggest that iron overload affects changes of collagen and TGF-$\beta$I gene expression and these changes are associated with liver fibrogenesis.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.753-759
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• 2002

$\beta$-Cyclodextrin glucanotransferase ($\beta$-CGTase) was overproduced extracellularly using recombinant E. coli by transforming the plasmid pECGT harboring a secretive signal peptide. The $\beta$-CGTase gene of alkalophilic Bacillus firmus var alkalophilus was inserted into the high expression vector pET20b(+) containing a secretive pelB signal peptide, and then transformed into E. coli BL2l(DE3)pLysS. The optimum culture conditions fer the overproduction of $\beta$-CGTase were determined to be TB medium containing 0.5% (w/v) soluble starch at post-induction temperature of $25^{\circ}C$. A significant amount of $\beta$-CGTase, up to 5.83 U/ml, which was nine times higher than that in the parent strain B. firmus var. alkalophilus, was overproduced in the extracellular compartment. A pH-stat fed-batch cultivation of the recombinant E. coli was also performed to achieve the secretive overproduction of $\beta$-CGTase at a high cell density, resulting in production of up to 21.6 U/ml of $\beta$-CGTase.

• Molecules and Cells
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• v.19 no.1
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• pp.131-136
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• 2005

The ETV6-NTRK3 gene fusion, first identified in the chromosomal translocation in congenital fibrosarcoma, encodes a chimeric protein tyrosine kinase with potent transforming activity. ETV6-NTRK3-dependent transformation involves the joint action of NTRK3 signaling pathways, and aberrant cell cycle progression resulting from activation of Mek1 and Akt. The level of glutathione (GSH) was found to be markedly increased in ETV6-NTRK3-transformed NIH3T3 cells. The activities of the two GSH biosynthetic enzymes as well as of glutathione peroxidase, together with their mRNAs, were also higher in the transformed cells. The transformed cells were able to grow in the presence of GSH-depleting agents, whereas the control cells were not. L-Buthionine-(S,R)-sulfoximine (BSO) inhibited activation of Mek1 and Akt in the transformed NIH3T3 cells. These observations imply that up-regulation of GSH biosynthesis plays a central role in ETV6-NTRK3-induced transformation.

• Molecules and Cells
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• v.42 no.2
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• pp.161-165
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• 2019

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths worldwide and has high rates of metastasis. Transforming growth factor beta-inducible protein (TGFBI) is an extracellular matrix component involved in tumour growth and metastasis. However, the exact role of TGFBI in NSCLC remains controversial. Gene silencing via DNA methylation of the promoter region is common in lung tumorigenesis and could thus be used for the development of molecular biomarkers. We analysed the methylation status of the TGFBI promoter in 138 NSCLC specimens via methylation-specific PCR and evaluated the correlation between TGFBI methylation and patient survival. TGFBI promoter methylation was detected in 25 (18.1%) of the tumours and was demonstrated to be associated with gene silencing. We observed no statistical correlation between TGFBI methylation and clinicopathological characteristics. Univariate and multivariate analyses showed that TGFBI methylation is significantly associated with poor survival outcomes in adenocarcinoma cases (adjusted hazard ratio = 2.88, 95% confidence interval = 1.19-6.99, P = 0.019), but not in squamous cell cases. Our findings suggest that methylation in the TGFBI promoter may be associated with pathogenesis of NSCLC and can be used as a predictive marker for lung adenocarcinoma prognosis. Further large-scale studies are needed to confirm these findings.

• The Korean Journal of Applied Statistics
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• v.22 no.3
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• pp.617-626
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• 2009

A series of recent papers reported that the inter-gene correlations in Affymetrix microarray data sets were strong and long-ranged, and the assumption of independence or weak dependence among gene expression signals which was often employed without justification was in conflict with actual data. Qui et al. (2005) indicated that applying the nonparametric empirical Bayes method in which test statistics were pooled across genes for performing the statistical inference resulted in the large variance of the number of differentially expressed genes. Qui et al. (2005) attributed this effect to strong and long-ranged inter-gene correlations. Klebanov and Yakovlev (2007) demonstrated that the inter-gene correlations provided a rich source of information rather than being a nuisance in the statistical analysis and they developed, by transforming the original gene expression sequence, a sequence of independent random variables which they referred to as a ${\delta}$-sequence. We note in this report using two cDNA microarray data sets experimented in this country that the strong and long-ranged inter-gene correlations were still valid in cDNA microarray data and also the ${\delta}$-sequence of independence could be derived from the cDNA microarray data. This note suggests that the inter-gene correlations be considered in the future analysis of the cDNA microarray data sets.

• Journal of Plant Biotechnology
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• v.3 no.1
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• pp.39-44
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• 2001

Plastid transformation was attempted with soybean [Glycine max (L.) Merr.] leaves and photoautotrophic and embryogenic cultures by particle bombardment using the transforming vector pZVII that carries the coding sequences for both subunits of Chlamydomonas reinhardtii Rubisco and a spectinomycin resistance gene (aadA). Spectinomycin resistant calli were selected from the bombarded leaves but the transgene was not present, indicating that the resistance was due to mutations. The Chlamydomonas rbcL and rbcS genes were shown to be site-specifically integrated into the plastid genome of the embryogenic cells with a very low transformation efficiency. None of the transformed embryogenic lines survived the plant regeneration process so no whole plants were recovered. This result does indicate that it should be possible to insert genes into the plastid genome of the important crop soybean if the overall methods are improved.