• Plant Biotechnology Reports
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• v.5 no.1
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• pp.1-7
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• 2011

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose and lignin surrounds the cellulose component of the plant's cell wall in order to protect the cell from enzymatic attacks. Such resistance, along with the variability seen in the proportions of the major components of the mixture, presents process design and operating challenges to the bioconversion of lignocellulosic biomass to fuel. Expanding bioenergy production to the commercial scale will require a significant improvement in the growth of feedstock as well as in its quality. Plant biotechnology offers an efficient means to create "targeted" changes in the chemical and physical properties of the resulting biomass through pathway-specific manipulation of metabolisms. The successful use of the genetic engineering approach largely depends on the development of two enabling tools: (1) the discovery of regulatory genes involved in key pathways that determine the quantity and quality of the biomass, and (2) utility promoters that can drive the expression of the introduced genes in a highly controlled manner spatially and/or temporally. In this review, we summarize the current understanding of the transcriptional regulatory network that controls secondary wall biosynthesis and discuss experimental approaches to developing-xylem-specific utility promoters.

• Journal of Photoscience
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• v.12 no.3
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• pp.129-133
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• 2005

The psbC gene, encoding the intrinsic chlorophyll-binding protein of CP43, one of the PS core complex polypeptides, was cloned from the Panax ginseng chloroplast, which is composed of 1,422 nucleotides and the overall nucleotide sequence shows more than 84% identity to those of eukaryotic photosynthetic organisms. The predicted topology of CP43, based on hydropathy analysis, includes six membrane-spanning ${\alpha}-helices$ resulting in three lumenal and four stromal loops. The putative translation start codon for the psbC gene is located at 48 nucleotides upstream from the stop codon of the psbD gene whose product is also a component of the PSII reaction center, implying that the promoter of the psbC gene is possibly located in the middle of the structural gene of the psbD gene. Northern blot analysis of the in vivo accumulation of the psbC transcript from the plants grown under the various growth light intensities (5%, 10%, 20%, and 100%) of daylight indicated that the steady-state level of the psbC transcript was not significantly affected by light intensity.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.425-430
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• 2006

Three hundred and sixty sexed 3-day-old broiler chicks were divided randomly into six treatment groups (control, antibiotic and black cumin at four levels) of 60 birds each. Black cumin seeds at 0.5%, 1%, 2% or 3% and avilamycin at 10 mg/kgt were added to the basal diet and their effects determined on feed intake, daily live weight gain, feed conversion ratio and carcass characteristics. There were no significant differences in daily feed intake at 21 and 42 days (p>0.05). Average daily gain was significantly different between the treatments. The birds fed the diet containing 1% black cumin seeds and antibiotic were the highest average daily gain, followed by those the other treatment diets and negative control (p<0.05). From 1 to 42 days of age, feed conversion ratios were improved significantly by supplementation with 1% black cumin seeds and with antibiotic (p<0.05) by approximately 5% compared to the control group. Similarly, the highest cold carcass, thigh, breast, wing, neck and liver weights were observed in the 1% black cumin and antibiotic groups (p<0.05). Accordingly, 1% supplementation of black cumin seeds to diets could be considered as an alternative natural growth promoter for poultry instead of antibiotics.

• BMB Reports
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• v.43 no.12
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• pp.807-812
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• 2010

$NF{\kappa}B$ and ZAS3 are transcription factors that control important cellular processes including immunity, cell survival and apoptosis. Although both proteins bind the ${\kappa}B$-motif, they produce opposite physiological consequences; $NF{\kappa}B$ activates transcription, promotes cell growth and is often found to be constitutively expressed in cancer cells, while ZAS3 generally represses transcription, inhibits cell proliferation and is downregulated in some cancers. Here, we show that ZAS3 inhibits $NF{\kappa}B$-dependent transcription by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. Transient transfection studies show that N-terminal 645 amino acids is sufficient to repress transcription activated by $NF{\kappa}B$, and that the identical region also possesses intrinsic repression activity to inhibit basal transcription from a promoter. Finally, in vitro DNA-protein interaction analysis shows that ZAS3 is able to displace $NF{\kappa}B$ by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. It is conceivable that ZAS3 has therapeutic potential for controlling aberrant activation of $NF{\kappa}B$ in various diseases.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.261-264
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• 2002

CHO (Chinese hamster ovary) cells were transfected with plasmids containing both cis-acting HRE (hypoxia response element) and CMV-promoter that controls tissue-type plasminogen activator (t-PA). CHO cells with HRE produced 16.2 fold higher t-PA concentration than CHO cells without HRE. It was noted that hypoxia strongly induced CHO cell apoptosis. which resulted in decrease of cell viability and protein production. In this study. by introducing Bcl-2, anti-apoptotic gene, we tried to recover cell viability and increase the protein production. When batch culture of both control cells without transfection of Bcl-2 and cells transfected with Bcl-2 were performed in the absence of CoCl ι hypoxia mimic condition. the cells with Bcl-2 were effected specific cell growth rates, maximum cell density. Immunoblotting assay showed Bcl-2 was recombinant with HRE dependent t- P A expression cassette, and their expression level was depended on hypoxia. By introducing Bcl-2, both cell viability and maximum cell density could be increased.

• Korean Chemical Engineering Research
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• v.58 no.2
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• pp.280-285
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• 2020

We have developed a constitutive display system of the Pseudomonas fluorescens SIK W1 TliA lipase on the cell surface of Escherichia coli using E. coli outer membrane protein C (OmpC) as an anchoring motif, which is an economical compared to induced system. For the constitutive expression of truncated OmpC-TliA fusion proteins, gntT104 promoter was employed. Cell growth was not affected by over expression of fusion protein during entire culture time, suggesting cell lysis was not a problem. The localization of truncated OmpC-TliA fusion protein on the cell surface was confirmed by immunofluorescence microscopy and measuring whole cell lipase activity. Constitutively displayed lipase was very stable, retaining activity enantioselectivity throughout the five repeated reactions. These results suggest that OmpC from E. coli be a useful anchoring motif for displaying enzymes on the cell surface without any inducers, and this stable surface display system can be employed for a broad range of biotechnological applications.

• Toxicological Research
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• v.23 no.3
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• pp.197-205
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• 2007

Cancer metastasis is a major determinant of cancer patient mortality. Mounting evidence favors a strong positive role for $TGF-{\beta}$ in human cancer progression. The complex pattern on cross-talk of $TGF-{\beta}$ and the related other signaling pathways is an important area of investigation that will ultimately contribute to understanding of the bifunctional role of $TGF-{\beta}$ in cancer progression. This review summarizes some of the current understanding of $TGF-{\beta}$ signaling with a major focus in its contribution to the tumor cell invasion and metastasis. Five issues are addressed in this review: (1) $TGF-{\beta}$ signaling, (2) $TGF-{\beta}$ and EMT, (3) $TGF-{\beta}$ and MMP, (4) $TGF-{\beta}$ and Ras, and (5) Role of $TGF-{\beta}$ in invasion and metastasis. Due to the bifunctional cellular effects of $TGF-{\beta}$, as a tumor promoter and a tumor suppressor, more precisely defined $TGF-{\beta}$ signaling pathways need to be elucidated. According to the current literature, $TGF-{\beta}$ is clearly a major factor stimulating tumor progression through a complex spectrum of the interplay and cross-talk between various signaling molecules. Understanding the role of $TGF-{\beta}$ in invasion and metastasis will provide valuable information on establishing strategies to manipulate $TGF-{\beta}$ signaling which should be a high priority for the development of anti-metastatic therapeutics.

• Molecules and Cells
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• v.40 no.10
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• pp.697-705
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• 2017

The maintenance of inorganic phosphate (Pi) homeostasis is essential for plant growth and yield. Plants have evolved strategies to cope with Pi starvation at the transcriptional, post-transcriptional, and post-translational levels, which maximizes its availability. Many transcription factors, miRNAs, and transporters participate in the Pi starvation signaling pathway where their activities are modulated by sugar and phytohormone signaling. Environmental stresses significantly affect the uptake and utilization of nutrients by plants, but their effects on the Pi starvation response remain unclear. Recently, we reported that Pi starvation signaling is affected by abiotic stresses such as salt, abscisic acid, and drought. In this review, we identified transcription factors, such as MYB, WRKY, and zinc finger transcription factors with functions in Pi starvation and other environmental stress signaling. In silico analysis of the promoter regions of Pi starvation-responsive genes, including phosphate transporters, microRNAs, and phosphate starvation-induced genes, suggest that their expression may be regulated by other environmental stresses, such as hormones, drought, cold, heat, and pathogens as well as by Pi starvation. Thus, we suggest the possibility of cross-talk between Pi starvation signaling and other environmental stress signaling pathways.

• The Journal of the Korean Society for Microbiology
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• v.35 no.2
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• pp.109-115
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• 2000

FtsH is a membrane-bound, ATP-dependent metalloprotease that is involved in a variety of cellular functions including the regulation of responses to heat and stress shock. Previously, we had cloned and sequenced pneumococcal ftsH gene whose deduced amino acid sequence was very similar to those of several gram-positive bacteria and Escherichia coli, except for the N-terminal domain that was responsible for membrane anchoring. In order to better understand the role of Streptococcus pneumoniae FtsH, we expressed pneumococcal ftsH gene in Escherichia coli. When it was expressed from a strong promoter, $P_{tac}$, a considerable amount of the recombinant FtsH was produced, although the prolonged induction resulted in not only accumulation of breakdown products but also ceasing of the further growth of E. coli host. This indicated that the expression of the exogenous ftsH gene was tightly regulated since the excessive FtsH appeared detrimental to bacterial cells. In Western blotting, the pneumococcal FtsH protein, whether native or recombinant, was reactive to anti-E. coli FtsH serum. The observation that FtsH proteins were well conserved throughout the bacterial kingdom and its expression level was fine-tuned suggests an important role for this protein in the stress adaptation which may be related to infecting process by pneumococci.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.556-561
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• 2012

Steroid sulfatase (STS) is responsible for the conversion of estrone sulfate to estrone that can stimulate growth in endocrine-dependent tumors such as prostate cancer. Although STS is considered as a therapeutic target for the estrogen-dependent diseases, cellular function of STS are still not clear. Previously, we found that tumor necrosis factor (TNF)-${\alpha}$ significantly enhances steroid sulfatase expression in PC-3 human prostate cancer cells through PI3K/Akt-dependent pathways. Here, we studied whether bacterial lipopolysaccharides (LPS) which are known to induce TNF-${\alpha}$ may increase STS expression. Treatment with LPS in PC-3 cells induced STS mRNA and protein in concentration- and time-dependent manners. Using luciferase reporter assay, we found that LPS enhanced STS promoter activity. Moreover, STS expression induced by LPS increased PC-3 tumor cell migration determined by wound healing assay. We investigated that LPS induced IL-6 expression and IL-6 increased STS expression. Taken together, these data strongly suggest that LPS induces STS expression through IL-6 pathway in human prostate cancer cells.