• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.240-244
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• 2022

Precisely reliable and quantitative reporters can provide phenotypes that are consistent with research goals in protein expression. Here, we developed an improved reporter mATglu III 5 by directed evolution using a versatile β-glucosidase ATglu derived from Agrobacterium tumefaciens. When expressed in hosts, a vector containing this mutant distinctly showed a colored or fluorescent phenotype, according to the supplemented substrate, without any inducer. Analysis of mATglu III 5 showed it to be fully functional in fusion state with oligomeric proteins, especially under non-induction conditions, thereby offering an alternative to conventional reporters.

• 순환기질환의공학회:학술대회논문집
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• 2006.10a
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• pp.10-13
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• 2006

Inflammation plays an important role in the progression of atherosclerosis and plaque destabilization converting a chronic process into an acute disorder with ensuing thromboembolism. Current therapeutic effective in preventing atherosclerosis and stroke such as statins, ASS and RAS inhibitors my exert part of their effects by modulating inflammatory responses in the vessel walls. As alternative approaches, discovery to find having inhibitory action of MMP activity, COX-2, macrophage infiltration, such as APE1/ref-1 and fusion technology for cell permeable protein may provide a new antiatherosclerotic therapy in the future.

• BMB Reports
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• v.32 no.5
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• pp.497-501
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• 1999

Biotinylation of recombinant proteins is a powerful tool for the detection and analysis of proteins of interest in a large variety of assay systems. The recent development of in vivo biotinylation techniques in E. coli has opened new possibilities for the production of site-specifically biotinylated proteins without the need for further manipulation after the isolation of the recombinantly expressed proteins. In the present study, a novel vector set was generated which allows the convenient cloning and expression of proteins of interest fused with an N-terminal in vivo biotinylated thioredoxin (TRX) protein. These vectors were derived from the previously reported pBIOTRX vector into which was incorporated part of the pBluescript II+phagemid multiple cloning site (MCS), amplified by PCR using a pair of sophisticated oligonucleotide primers. The functionality of these novel vectors was examined in this system by recombinant expression of rat transforming growth factor-$\beta$. Western-blot analysis using TRX-specific antibodies or peroxidase-conjugated streptavidin confirmed the successful induction of the fusion protein and the in vivo conjugation of biotin molecules, respectively. The convenience of molecular subcloning provided by the MCS and the effective in vivo biotinylation of proteins of interest makes this novel vector set an interesting alternative for the production of biotinylated proteins.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.172-177
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• 2002

This study was conducted to investigate the utilization of Sargassum meal in the diet on juvenile ayu (Plecoglossus altivelis) reared in seawater. White fish meal and wheat flour were used as the dietary protein and carbohydrate sources in the control diet. Wheat flour in the control diet was replaced with $5\%$ and $10\%$ Sargassum meal. Three replicate groups of fish average weighing 4.0 g were fed one of three isonitrogenous$(45\%)$ and isocaloric (14.5 MJ /kg diet) diets for 7 weeks. Survival of all groups were above $80\%$. Weight gain, feed efficiency and protein efficiency ratio were not significantly affected by dietary Sargassum meal levels (P>0.05). There were no significant differences (P>0.05) in moisture, crude protein, crude lipid, crude ash and fatty acid compositions of whole-body fish among groups. It is concluded that Sargassum meal could be used as a dietary additive or alternative low-cost dietary ingredient up to $10\%$ for juvenile ayu reared in seawater.

• BMB Reports
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• v.42 no.3
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• pp.178-183
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• 2009

Tyrosinase (TYR) plays a critical role in cellular melanogenesis and, thus, has been the major target of pharmacological approaches for the control of skin pigmentation. This study examined an alternative molecular approach using TYR-small interfering RNA (siRNA) to control melanogenesis in the human melanocytes. Both the mRNA and protein levels of TYR were significantly lowered by TYR-siRNA treatment, whereas TYR-related protein 1 and TYR-related protein 2 displayed no such changes. TYR-siRNA treatment inhibited the cellular melanin synthesis from the externally supplied TYR substrate L-tyrosine. TYR-siRNA also suppressed melanin synthesis and decreased the viability of cells exposed to ultraviolet radiation, supporting a critical role of melanin in protection against ultraviolet radiation. These results suggest that molecular approaches using siRNA targeted to the enzymes of melanogenic pathway may provide a novel strategy for the control of cell pigmentation.

• Korean Journal of Computational Design and Engineering
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• v.14 no.6
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• pp.404-414
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• 2009

In the computational molecular analysis, 3D structural comparison for protein searching plays a very important role. As protein databases have been grown rapidly in size, exhaustive search methods cannot provide satisfactory performance. Because exhaustive search methods try to handle the structure of protein by using sphere set which is converted from atoms set, the similarity calculation about two sphere sets is very expensive. Instead, the filter-and-refine paradigm offers an efficient alternative to database search without compromising the accuracy of the answers. In recent, a very fast algorithm based on the inter-atomic distance has been suggested by Ballester and Richard. Since they adopted the moments of distribution with inter-atomic distance between atoms which are rotational invariant, they can eliminate the structure alignment and orientation fix process and perform the searching faster than previous methods. In this paper, we propose a new 3D shape descriptor. It has properties of the general shape distribution and useful property in screening the molecular database. We show some experimental results for the validity of our method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1766-1772
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• 2009

In this study, we are interested in comparing the protein profiles of acid-shocked and control cells of S. mutans isolated from Korean children with caries. The results of 2D gel electrophoresis showed that twelve proteins are up-regulated when the cells were grown under 20 mM lactic acid stress in the exponential phase. Up-proteins under acid stress were estimated a major key of the survival and proliferation of S. mutans in low pH environments. These proteins are estimated generally associated with three biochemical pathways: glycolysis, alternative acid production and branched-chain amino acid biosynthesis.

• Molecules and Cells
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• v.21 no.1
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• pp.21-28
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• 2006

The interferon-induced, double-stranded RNA (dsRNA)-dependent protein kinase PKR plays a key role in interferon-mediated host defense against viral infection, and is implicated in cellular transformation and apoptosis. We have isolated a cDNA of simian PKR encoding a product with 83% amino acid identity to the human homolog and showed that PKR expression is significantly attenuated in the Vero E6 African green monkey kidney cells devoid of type I interferon genes. A variant form of PKR lacking the exon 12 in the kinase domain is produced in these cells, presumably from an alternatively spliced transcript. Unlike wild type PKR, the variant protein named PKR-${\Delta}E12$ is incapable of auto-phosphorylation and phosphorylation of eIF2-${\alpha}$, indicating that the kinase sub-domains III and IV embedded in exon 12 are indispensable for catalytic function. PKR-${\Delta}E12$ had no dominant negative effect but was weakly phosphorylated in trans by wild type PKR.

• BMB Reports
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• v.54 no.7
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• pp.335-343
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• 2021

Cancer stem cells (CSCs) are a subpopulation of cancer that can self-renew and differentiate into large tumor masses. Evidence accumulated to date shows that CSCs affect tumor proliferation, recurrence, and resistance to chemotherapy. Recent studies have shown that, like stem cells, CSCs maintain cells with self-renewal capacity by means of asymmetric division and promote cell proliferation by means of symmetric division. This cell division is regulated by fate determinants, such as the NUMB protein, which recently has also been confirmed as a tumor suppressor. Loss of NUMB expression leads to uncontrolled proliferation and amplification of the CSC pool, which promotes the Notch signaling pathway and reduces the expression of the p53 protein. NUMB genes are alternatively spliced to produce six functionally distinct isoforms. An interesting recent discovery is that the protein NUMB isoform produced by alternative splicing of NUMB plays an important role in promoting carcinogenesis. In this review, we summarize the known functions of NUMB and NUMB isoforms related to the proliferation and generation of CSCs.

• Molecules and Cells
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• v.20 no.2
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• pp.263-270
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• 2005

Transactivation of EGF-receptor (EGFR) by G-protein coupled receptors (GPCRs) is emerging as an important pathway in cell proliferation, which plays a crucial role in the development of atherosclerotic lesion. Angiotensin II (Ang II) has been identified to have a major role in the formation of atherosclerotic lesions, although the underlying mechanisms remain largely unclear. We hypothesize that Ang II promotes the proliferation and migration of smooth muscle cells through the release of heparin-binding epidermal growth factor like growth factor (HB-EGF), transactivation of EGFR and activation of Akt and Erk 1/2, with matrix metalloproteases (MMPs) playing a dispensable role. Primary rat aortic smooth muscle cells were used in this study. Smooth muscle cells rendered quiescent by serum deprivation for 12 h were treated with Ang II (100 nM) in the presence of either GM6001 ($20{\mu}M$), a specific inhibitor of MMPs or AG1478 ($10{\mu}M$), an inhibitor of EGFR. The levels of phosphorylation of EGFR, Akt and Erk 1/2 were assessed in the cell lysates. Inhibition of MMPs by GM6001 significantly attenuated Ang II-stimulated phosphorylation of EGFR, suggesting that MMPs may be involved in the transactivation of EGFR by Ang II receptor. Furthermore Ang II-stimulated proliferation and migration of smooth muscle cells were significantly blunted by inhibiting MMPs and EGFR and applying HB-EGF neutralization antibody, indicating that MMPs, HB-EGF and EGFR activation is necessary for Ang-II stimulated migration and proliferation of smooth muscle cells. Our results suggest that inhibition of MMPs may represent one of the strategies to counter the mitogenic and motogenic effects of Ang II on smooth muscle cells and thereby prevent the formation and development of atherosclerotic lesions.