• BMB Reports
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• 제28권5호
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• pp.458-463
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• 1995

Two apparent rho-independent transcription terminator structures within the coding sequence of aceK have been destroyed to access their roles in the differential expression between aceA and aceK in the glyoxylate bypass operon of E. coli. The effect of mutations on the expression of aceK was evaluated in two different ways: one by maxicell labeling and the other by lacZ fusion gene construction. The maxicell labeling experiment with the mutant operon clones has failed, like that of the wild type operon clone, to visibly show isocitrate dehrogenase (IDH) kinase/phosphatase, the product of aceK, on the autoradiogram of a protein gel. When the same mutations were introduced into an aceK::lacZ fusion gene to quantitatively evaluate the mutational effect, the activity of ${\beta}-galactosidase$ in neither of the mutant versions of the fusion gene was elevated significantly enough to explain the degree of polarity observed in this region. Thus, we conclude that neither of these intragenic, apparent rho-independent transcription terminator structures, which have long been suspected as a major determinant in the down regulation of aceK, really act as a premature transcriptional terminator.

• Journal of Microbiology and Biotechnology
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• 제2권4호
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• pp.237-242
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• 1992

In order to clone the gene coding for alkaline phosphatase in the yeast Kluyveromyces fragilis, a genomic library was constructed using the yeast-E. coli shuttle vector pHN114 as a cloning vector. From the genomic library, a clone carrying the gene was isolated and the plasmid was designated as pSKH101. A restriction enzyme map was made using this plasmid. Subcloning experiments and complementation studies showed that alkaline phosphatase was active only in the original 3.1 kb insert. Southern hybridization analysis confirmed that the cloned DNA fragment was derived from K. fragilis genomic DNA. Using a minicell experiment, the product of the cloned gene was identified as a protein with a molecular weight of 63 KDa. A 0.6 kb HindIII fragment, which showed promoter activity, was isolated using the E. coli promoter-probe vector pKO-1.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1367-1372
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• 2000

The present study was conducted to evaluate the efficiency of transgenic rabbit production by DNA microinjection using EGFP (Enhanced Green Fluorescent Protein) gene. In this experiment EGFP coding sequences fused to CMV promoter were microinjected into rabbit one-cell embryos, and then GFP expression and gene integration were evaluated in preimplantation embryos and fetuses recovered on day 15 of pregnancy to determine efficiency of transgenic rabbit production. Effect of DNA concentration was also tested on development in vitro following microinjection and transgene integration in fetuses. Development of embryos in vitro was decreased by DNA microinjection, but the rates of pregnancy and implantation were not significantly affected by microinjection. As development progressed in vitro percentage of GFP expression in rabbit embryos was decreased, resulting GFP expression detected in 37.5% of blastocysts. The efficiencies for production of transgenic fetuses were 4.0% and 7.6%, respectively, when $10ng/{\mu}l$ and $20ng/{\mu}l$ of DNA concentration were microinjected. Transgenic fetuses were confirmed by GFP expression and PCR analysis of fetus genomic DNA. These results indicated that DNA microinjection itself damaged embryo development and DNA concentration affected the efficiency of transgenic rabbit production.

• Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.325-335
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• 2012

The present study characterized the fast skeletal myosin light chain-2 gene (mlc2f) in the euryhaline Javanese ricefish (Oryzias javanicus: Beloniformes). Coding nucleotide and deduced amino acid sequences of Javanese ricefish mlc2f were well conserved in the vertebrate lineage. Javanese ricefish mlc2f showed a typical seven-exon structure, and its promoter exhibited transcription factor binding motifs common to most muscle-specific genes. However, Javanese ricefish mlc2f also displayed tandem duplications of intronic sequences in both intron 1 and intron 3. Based on quantitative reverse transcription-polymerase chain reaction, the mlc2f transcripts were highly predominant in skeletal muscles of adults and were differentially modulated during embryonic development. Microinjection of the mlc2f promoter-driven red fluorescent protein (RFP) reporter construct successfully exhibited heterologous expression of the fluorescent reporter, primarily in muscular areas of hatchlings, although the distribution pattern of RFP signals was not uniform due to the mosaic nature of the introduced transgene. Data from this study indicate that the Javanese ricefish mlc2f gene has undergone "intra-intronic" duplication events in a species-specific manner and that the mlc2f regulator may also be useful in heterologous expression assays of the skeletal muscles of this species.

• 한국잠사곤충학회지
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• 제38권2호
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• pp.144-149
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• 1996

곤충 바이러스인 Baculoviridae의 subgroup A에 속하는 핵다각체병 바이러스는 미생물 살충제로서, 또는 유용물질의 생산을 위한 발현벡터로서 현재 널리 연구·이용되고 있다. 본 연구에서는 이러한 NPV중 국내에서 분리된 SeNPV의 다각체 단백질 유전자의 구조적 특성을 구명함으로써 새로운 발현벡터를 제작하고자 하였다. 이를 위해 SeNPV의 다각체 모양을 전자현미경으로 관찰하고, 다각체 단백질의 분자량과 그 유전자의 구조를 각각 SDS-PAGE 및 염기서열 결정법에 의해 결정하였다. 그 결과, SeNPV의 다각체는 분자량 30 kDa의 단일 단백질로 이루어진 부정형의 구조였으며, 다각체 단백질 유전자의 염기서열을 포함한 876 염기의 서열을 결정하였다. 또한, SeNPV 전체 DNA상에서 다각체 단백질 유전자는 Xho I 3.0 Kb와 Nco I 6.0 Kb에 각각 존재함을 확인하고, 각각 cloning하여 제한효소 지도를 작성하였다.

• 한국자원식물학회지
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• 제23권6호
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• pp.535-540
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• 2010

Phenylalanine ammonia-lyase (PAL), a key enzyme of the phenylpropanoid biosynthesis pathway, is activated by a number of developmental and environmental cues. The coding region of the NtPAL4 gene was 2,154 bp in length, and its deduced protein was composed of 717 amino acids. Sequence analysis of NtPAL4 cDNA from tobacco (Nicotiana tabacum L.) revealed high structural similarity to PAL genes of other plant species. The NtPAL4 gene exists as a single copy in the tobacco plant, and its transcripts were strongly expressed in flowers and leaves. NtPAL4 expression was significantly induced in response to NaCl, mannitol, and cold treatments, but it was not induced by abscisic acid (ABA). NtPAL4 expression decreased gradually after treatment with ABA and $H_2O_2$; however, NtPAL4 transcripts accumulated after treatment with methyl viologen (MV). Our results suggest that the NtPAL4 gene may function in response to abiotic stresses.

• Journal of Microbiology
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• 제34권2호
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• pp.151-157
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• 1996

By PCR amplification using the sequence of the previously cloned shiga-like toxin II DNA, a gene encoding it has been cloned from an isolate of healthy Korean native bovine feces, Escherichia coli KSC109. The nucleotide sequence s included tow open reading frames coding for 319 and 89 amino acids corresponding to A and B subunits, respectively. Comparison of the nucleotide and predicted amino acid sequences of newly cloned gene (slt-II) with those of others in the SLT-II family revealed completely identical homology with SLT-II cloned previously from bacteriophabe DNA of E. coli 933 derived from a patient with hemorrhagic colities. In addition, the sequence homology of SLT-II with SLT-II variant form bovine was more than 95% at both the nucleotide and protein levels. Overexpression of SLT-II recombinant gene by induction with IPTG using an E, coli hostvector, system was conducted and the correctly processed products with active mature form exhibited 1000-fold higher cytotoxycity for Vero cells than that form original strain.

• Genomics & Informatics
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• 제5권3호
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• pp.107-112
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• 2007

MicroRNAs (miRNAs) are known to negatively control protein-coding genes by binding to messenger RNA (mRNA) in the cytoplasm. In innate immunity, the role of miRNA gene silencing is largely unknown. In this study, we performed microarray-based experiments using lipopolysaccharide (LPS)-stimulated macrophages derived from wild-type, MyD88 knockout (KO), TRIF KO, and MyD88/TRIF double KO mice. We employed a statistical approach to determine the importance of the commonality and specificity of miRNA binding sites among groups of temporally co-regulated genes. We demonstrate that both commonality and specificity are irrelevant to define a priori groups of co-down regulated genes. In addition, analyzing the various experimental conditions, we suggest that miRNA regulation may not only be a late-phase process (after transcription) but can also occur even early (1h) after stimulation in knockout conditions. This further indicates the existence of dynamic interactions between miRNA and signaling molecules/transcription factor regulation; this is another proof for the need of shifting from a 'hard-wired' paradigm of gene regulation to a dynamical one in which the gene co-regulation is established on a case-by-case basis.

• 대한의생명과학회지
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• 제26권1호
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• pp.22-27
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• 2020

Tuberculosis is airborne disease caused by Mycobacterium tuberculosis (MTB). Host genetic factors of these tuberculosis play an important role in determining individual difference in susceptibility or resistance to infectious diseases including tuberculosis. CD247 is named CD3zeta chain or CD3ζ. CD247 gene is a protein-coding gene involved in phagocytosis and signal transduction of the T cell receptor (TCR). Also, downregulation of the CD3ζ chain has been associated to chronic inflammation. The aim of this study was to research association of the genetic polymorphisms for CD247 gene and tuberculosis. We analyzed association of CD247 and Mycobacterium tuberculosis using 149 imputed single nucleotide polymorphisms (SNPs) with Korean population. And the results of this study show that seven SNPs of CD247 were identified to associate with tuberculosis. The most significant SNP was rs858545 (OR=1.22, CI: 1.05~1.42, P=0.009481). This study suggests that polymorphisms of CD247 may affect the T cell receptor signaling pathway, which may associate the infection of tuberculosis.

• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.8-12
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• 1997

In order to overproduce D-xylose isomerase, the Escherichia coli D-xylose isomerase (D-xylose ketol-isomerase, EC 5.3.1.5) gene (xylA) was fused to ${\lambda}P_{L}$ promoter. The promoterless xylA gene containing the ribosome binding site and coding region for D-xylose isomerase was cloned into a site 0.3 kb downstream from the ${\lambda}P_{L}$ promoter on a high copy number plasmid. An octameric XbaI linker containing TAG amber codon was inserted between 33rd codon of ${\lambda}N$ and the promoterless xylA gene. The resulting recombinant plasmid (designated as pPX152) was transformed into E. coli M5248 carrying a single copy of the temperature sensitive ${\lambda}cI857$ gene on its chromosomal DNA. When temperature-induced, the transformants produced 15 times as much D-xylose isomerase as that of D-xylose-induced parent strain. The amount of overproduced D-xylose isomerase was found to be about 60% of total protein in cell-free extracts.