• Korean Journal of Microbiology
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• v.46 no.1
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• pp.104-108
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• 2010

We describe the construction of derivatives of wild type and mutant lrp genes that encode 6XHis-tag Lrps. These derivatives of wild type and mutant Lrp could be useful for in vitro studies including Lrp conformational changes. We show that 6XHis-tag Lrp wild type and 6XHis-tag Lrp R145W bind with similar patterns in vitro to 21 bp duplex DNA containing the consensus sequences of Lrp sites of upstream of the ilvIH operon. In addition, we report here the 6XHis-tag Lrp R145W is useful to investigate the conformational changes of Lrp in solution by using its own intrinsic fluorescence characteristics.

• Korean Journal of Veterinary Research
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• v.36 no.3
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• pp.627-633
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• 1996

To analyze the genomic diversity of transmissible gastroenteritis virus (TGEV), the N-terminal half of the spike (S) glycoprotein gene and nonstructural protein gene (open reading frames 3 and 3-1) were amplified by reverse transcriptase reaction and polymerase chain reaction (RT-PCR), and analyzed using restriction fragment length polymorphism (RFLP) patterns of the amplified DNA. In this study, TGEV Miller (M6) and Purdue (P115) strains were used as reference strains, and two vaccine strains (MSV and STC3) and four Korea isolates (P44, VRI-WP, VRI-41, and VRI-48) were analyzed. All TGEV strains were amplified with three TGEV primer pairs. Although there was some exception in RFLP analysis, this method differentiated TGEV strains into following groups : Miller group (M6 and MSV), Purdue group (PUS, STC3, P44, VRI-WP, VRI-41, and VRI-48). Using Sau3AI and SspI, VRI-48 was differentiated from the Miller and Purdue type viruses. The RT/PCR in conjuction with RFLP analysis was a rapid and valuable tool for differentiating several strains of TGEV. This study revealed the occurences of distinct difference in genome of TGEV strains.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.51-54
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• 2003

Analysis of the Neurospora crassa genome data reveals at least 14 proteins that contain tetratricopeptide repeat (TPR) motifs. One of them shows over $60\%$ homology with SSN6 of Saccharomyces cerevisiae, a global repressor that mediates repression of genes involved in various cellular processes. Sequence analysis of its cDNA shows that it encodes a putative 102kDa protein. Mutant strains generated by RIP (repeat induced point mutation) process show four distinctive patterns of vegetative growth at various rates. They are male-fertile, yet all female-sterile and produced little or no perithecium. These results indicate that this gene is pleiotropic and involved in several cellular processes of vegetative growth, conidiation and sexual cycle. It is designated rcm-1(regulation of conidiation and morphology).

• Proceedings of the Korean Society of Applied Pharmacology
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• 2000.04a
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• pp.17-19
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• 2000

Heterotrimeric G Proteins transduce ligand binding to a wide variety of seven transmembrane cell surface receptors into intracellular signals. The currently accepted model for the activation of G protein suggests that ligand-activated receptor accelerates GDP-GTP exchange reactions on the ${\alpha}$ subunit of the heterotrimeric G protein. At least seventeen distinct isoforms of the G${\alpha}$ subunit protein have been identified in mammalian organisms. Among them, the G${\alpha}$q family consists of five members whose ${\alpha}$ subunits show different expression patterns. G${\alpha}$q and G${\alpha}$11 seem to be almost ubiquitously expressed, whereas G${\alpha}$14 is predominantly expressed in spleen, lung, kidney and testis. G${\alpha}$16 and its murine counterpart G${\alpha}$15 are expressed in hematopoietic cells and has been shown to couple a wide variety of receptors to phosphoinositide-specific phospholipase C activity. Beta-isoforms of phospholipase C were shown to be activated by all members of G${\alpha}$q family, i.e., G${\alpha}$q, G${\alpha}$11, G${\alpha}$l4 and G${\alpha}$16 subunits either in reconstitution system. or in experiments using cDNA transfection with intact Cos-7 cells.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.2
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• pp.164-173
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• 2000

The p16 protein is a cyclin dependent kinase inhibitor that inhibits cell cycle progression from $G_1$ phase to S phase in cell cycle. Many p16 gene mutations have been noted in many cancer-cell lines and in some primary cancers, and alterations of p16 gene function by DNA methylation have been noticed in various kinds of cancer tissues and cell-lines. There have been a large body of literature has accumulated indicating that abnormal patterns of DNA methylation (both hypomethylation and hypermethylation) occur in a wide variety of human neoplasma and that these aberrations of DNA methylation may play an important epigenetic role in the development and progression of neoplasia. DNA methylation is a part of the inheritable epigenetic system that influences expression or silencing of genes necessary for normal differentiation and proliferation. Gene activity may be silenced by methylation of up steream regulatory regions. Reactivation is associated with demethylation. Although evidence or a high incidence of p16 alterations in a variety of cell lines and primary tumors has been reported, that has been contested by other investigators. The precise mechanisms by which abnormal methylation might contribute to carcinogenesis are still not fully elucidated, but conceivably could involve the modulation of oncogene and other important regulatory gene expression, in addition to creating areas of genetic instability, thus predisposing to mutational events causing neoplasia. There have been many variable results of studies of head and neck squamous cell carcinoma(HNSCC). This investigation was studied on 13 primary HNSCC for p16 gene status by protein expression in immunohistochemistry, and DNA genetic/epigenetic analyzed to determine the incidence, the mechanisms, and the potential biological significance of its Inactivation. As methylation detection method of p16 gene, the methylation specific PCR(MSP) is sensitive and specific for methylation of any block of CpG sites in a CpG islands using bisulfite-modified DNA. The genomic DNA is modified by treatment with sodium bisulfate, which converts all unmethylated cytosines to uracil(thymidine). The primers designed for MSP were chosen for regions containing frequent cytosines (to distinguish unmodified from modified DNA), and CpG pairs near the 5' end of the primers (to provide maximal discrimination in the PCR between methylated and unmethylated DNA). The two strands of DNA are no longer complementary after bisulfite treatment, primers can be designed for either modified strand. In this study, 13 paraffin embedded block tissues were used, so the fragment of DNA to be amplified was intentionally small, to allow the assessment of methylation pattern in a limited region and to facilitate the application of this technique to samlples. In this 13 primary HNSCC tissues, there was no methylation of p16 promoter gene (detected by MSP and automatic sequencing). The p16 protein-specific immunohistochemical staining was performed on 13 paraffin embedded primary HNSCC tissue samples. Twelve cases among the 13 showed altered expression of p16 proteins (negative expression). In this study, The author suggested that low expression of p16 protein may play an important role in human HNSCC, and this study suggested that many kinds of genetic mechanisms including DNA methylation may play the role in carcinogenesis.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.7
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• pp.933-941
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• 2005

To develop a functional cDNA chip, specific genes expressed in the tissues of swine Kagoshima Berkshire were screened. A total of 4,434 ESTs were obtained by constructing a cDNA library from total RNA isolated from the muscle and fat tissues, affirming their functions by investigating similarity of nucleotide sequences with the database at the NCBI. Among them, 1,230 ESTs were confirmed as novel genes, which, to date, have not been identified. Attaching the genes to a cDNA microarray slide revealed expression patterns of genes in muscle and fat according to the growth stages of swine. As specific genes expressed in the muscle tissues of swine with body weight of 30 kg, 60 genes including actin, myosin, tropomysin, transfer RNA-trp synthetase, Kel-like protein 23, KIAA0182 and COI, Foocen-m, etc were obtained. In addition, 18 novel genes were obtained. As specific genes expressed in fat tissues of swine with body weight of 30 kg, 47 genes including annexin II, Collagen, Fibronectin, Pleckstrin homology domain, serine protease, etc were obtained. 21 novel genes were also obtained. The genes specifically expressed in the muscle and fat tissues of swine affect contraction and relaxation of the muscle and the fat. However, studies on the expression mechanisms of the genes are insufficient. To reveal species of structural genes in swine muscle and fat tissue, interrelation studies in expression and function of genes by using the cDNA chip should be conducted.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.459-465
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• 1996

Bacillus thuringiensis serovar. darmstadiensis produced bipyramidal endo-toxin. The toxin protein was purified by Renografin-76 step gradient centrifugation and investigated by electron microscope. Analysis of total plasmid DNA patterns showed that four different size of plasmids existed in wild type B. thuringiensis serovar. darmstadiensis. Total plasmids DNA was isolated and transformed into pst I site of pBR322 cloning vector. Ten clones containing crystal toxin gene were forst screened colony hybridization by using PUYBT 9044 probe ontained B. thuringiensis kurskaki HD 1 toxin gene. Cloned-DNA was digested with EcoR1 and HindIII and transformed to pIBI30 sequencing vector. Finally, 2.6kb and 3.6kb size fragments contatined toxin-gene were cloned with restriction analysis.

• Journal of Plant Biotechnology
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• v.50
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• pp.190-199
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• 2023

Date palm (Phoenix dactylifera L.: Arecaceae) is a dioecious species where only female trees bear fruits. In their natural state, date palms produce dates once a year. However, in Thailand, some trees were observed to produce dates during the off-season, despite no variations in morphology. The availability of such off-season fruits can significantly increase their market value. Interestingly, most female off-season date palms investigated in this study were obtained through micropropagation. Hence, there is an urgent need for genetic markers to distinguish female offseason flowering plantlets within tissue culture systems. In this study, we aimed to develop random amplification of polymorphic DNA-sequence characterized amplified region (RAPD-SCAR) markers for the identification of female off-season flowering date palms cultivated in Thailand. A total of 160 random decamer primers were employed to screen for specific RAPD markers in off-season flowering male and female populations. Out of these, only one primer, OPN-02, generated distinct genomic DNA patterns in female off-season flowering (FOFdp) individuals compared to female seasonal flowering genotypes. Based on the RAPD-specific sequence, specific SCAR primers denoted as FOFdpF and FOFdpR were developed. These SCAR primers amplified a single 517-bp DNA fragment, predominantly found in off-season flowering populations, with an accuracy rate of 60%. These findings underscore the potential of SCAR marker technology for tracking offseason flowering in date palms. Notably, a BLAST analysis revealed a substantial similarity between the SCAR marker sequence and the transcript variant mRNA from Phoenix dactylifera encoding the SET DOMAIN GROUP 40 protein. In Arabidopsis, this protein is involved in the epigenetic regulation of flowering time. The genetic potential of the off-season flowering traits warrants further elucidation.

• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1196-1206
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• 2014

A metagenomic fosmid library was constructed using genomic DNA isolated from the gut microflora of Hermetia illucens, a black soldier fly. A cellulase-positive clone, with the CS10 gene, was identified by extensive Congo-red overlay screenings for cellulase activity from the fosmid library of 92,000 clones. The CS10 gene was composed of a 996 bp DNA sequence encoding the mature protein of 331 amino acids. The deduced amino acids of CS10 showed 72% sequence identity with the glycosyl hydrolase family 5 gene of Dysgonomonas mossii, displaying no significant sequence homology to already known cellulases. The purified CS10 protein presented a single band of cellulase activity with a molecular mass of approximately 40 kDa on the SDS-PAGE gel and zymogram. The purified CS10 protein exhibited optimal activity at $50^{\circ}C$ and pH 7.0, and the thermostability and pH stability of CS10 were preserved at the ranges of $20{\sim}50^{\circ}C$ and pH 4.0~10.0. CS10 exhibited little loss of cellulase activity against various chemical reagents such as 10% polar organic solvents, 1% non-ionic detergents, and 0.5 M denaturing agents. Moreover, the substrate specificity and the product patterns by thin-layer chromatography suggested that CS10 is an endo-${\beta}$-1,4-glucanase. From these biochemical properties of CS10, it is expected that the enzyme has the potential for application in industrial processes.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.509-514
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• 2004

Six new serovarieties of B. thuringiensis carrying specific H-antigen have minor differences in biochemical characteristics and morphological characteristics of crystals, which are commonly resistant against four antibiotics. The B. thuringiensis serovar. coreanensis is nontoxic to silkworm larvae, but it is moderately toxic against the Culex pipiens larvae. The B. thuringiensis serovar. konkukian and leesis are nontoxic against mosquitos larvae, but are toxic against silkworm larvae. The B. thuringiensis serovar. seoulensis, sooncheon, and yosoo are highly toxic to B. mori larvae and moderately toxic to C. pipiens larvae. The six serovarieties harbor different plasmid DNA patterns. A 102-kDa protein is a major crystal protein in the four serovarieties and a 86-kDa protein is in one serovariety.