• Proceedings of the Botanical Society of Korea Conference
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• 1985.08b
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• pp.73-81
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• 1985

We have previously isolated OsMADS4 gene that is a member of the class B MADS box genes from rice. In this study, another member of the class B MADS box genes was isolated from rice flower by the yeast two-hybrid screening method using OsMADS4 as bait. RNA blot analyses revealed that the clone, OsMADS16, was expressed in the second and third whorls, whereas the OsMADS4 transcripts were present in the second, third, and fourth whorls. These expression patterns of the OsMADS16 and OsMADS4 genes are very similar with those of AP3 and PI, the class B genes of Arabidopsis, respectively. In the yeast two-hybrid system, OsMADS4 interacted only with OsMADS16 among several rice MADS genes investigated, suggesting that OsMADS4 and OsMADS16 function as a heterodimer in specifying sepal and petal identities. We have also isolated OsMADS6 gene using OsMADS1 as a probe. Both are members of the AGL2 MADS family. Various MADS genes that encode for protein-protein interaction partners of the OsMADS6 protein were isolated by the yeast two-hybrid screening method. A majority of these genes belong to the AGL2 family. Sequence Homology, expression pattern, and ectopic expression phenotypes indicated that one of the interaction partners, OsMADS14, appears to be homologous to API, the class A MADS gene of Arabidopsis.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.351-357
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• 2005

Here I describe a multiplex allele specific PCR-based approach for the rapid detection between Hanwoo and Holstein meat associated with Melanocortin 1 receptor (MC1R) gene. Specific and universal oligonucleotide primers were used in combination to detect the presence of a single nucleotide polymorphism within the bovine MC1R DNA sequence. The presence of the bovine MC1R gene is indicated by the production of a single control PCR product, whilst positive samples generate an alternative smaller specific product over the same region. The mutations in MC1R104 codon revealed depending on the presence or absence of an indicative fragment amplified from the wild-type allele of this codon. As little as 0.39 ng and 1.56 ng of genomic DNA of Hanwoo and Holstein could be detected by MAS-PCR assay, respectively. This technique, which is widely used in human genetic screening, provides a reliable and sensitive result that has not been documented for the identification of bovine coat color. The MAS-PCR assay approach was proven to be useful in complementing routine beef DNA analysis for differentiation of these MC1R variants and it would facilitate the screening of deceiving sales of Holstein meat in the butcher shop.

• Journal of Microbiology
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• v.38 no.4
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• pp.230-238
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• 2000

Class III chitin synthases in filamentous fungi are important for hyphal growth and differentiation of several filamentous fungi. A genomic clone containing the full gene encoding Chs4, a class III chitin synthase in Penicillium chrysogenum, was cloned by PCR screening and colony hybridization from the genomic library. Nucleotide sequence analysis and transcript mapping of chs4 revealed an open reading frame (ORF) that consisted of 5 exons and 4 introns and encoded a putative protein of 915 amino acids. Nucleotide sequence analysis of the 5'flanking region of the ORF revealed a potential TATA box and several binding sites for transcription activators. The putative transcription initiation site at -716 position was identified by primer extension and the expression of the chs4 during the vegetative growth was confirmed by Northern blot analysis. Amino acid sequence analysis of the Chs4 revealed at least 5 transmembrane helices and several sites for past-transnational modifications. Comparison of the amino acid sequence of Chs4 with those of other fungi showed a close relationship between P chrysogenum and genus Aspergillus.

• KSBB Journal
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• v.22 no.5
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• pp.356-361
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• 2007

Cyanobacteria are a very old group of prokaryotic organisms that produce very diverse secondary metabolites, especially non-ribosomal peptide and polyketide structures. Although some cyanobacteria produce lethal toxins such as microcystins and anatoxins, some may be useful either for development into commercial drugs or as biochemical tools. Detection of unknown secondary metabolites was carried in the present study by a screening of 98 cyanobacterial strains from Cyanobiotech GmbH in order to establish a screening process, isolate pure substances and determine their bioactivities. A degenerated polymerase chain reaction technique as molecular approaches has been used for general screening of NRPS gene and PKS gene in cyanobacteria. A putative PKS gene was detected by DKF/DKR primer in 38 strains (38.8%) and PCR amplicons resulted from a presence of NRPS gene were showed by MTF2/MTR2 primer in 30 strains (30.6%), respectively. A screening of interesting strains was performed by comparing PCR screening results with HPLC analyses of extracts. HPLC analysis for a detection of natural products was performed in extracts from biomass. 5 strains were screened for further scale-up processing. 7 pure substances were isolated from the scale-up cultures and tested for bioactivities under consideration to purity, amount and molecular weight of substances. One substance isolated from CBT 635 showed cytotoxic activity. This substance may be regarded as Microcystin LR.

• Animal cells and systems
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• v.7 no.2
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• pp.159-164
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• 2003

The RAD3 gene of Saccharomyces cerevisiae is required for excision repair and is essential for cell viability. The RAD3 encoded protein possesses a single stranded DNA-dependent ATPase and DNA and DNA-RNA helicase activities. To examine the extent of conservation of structure and function of a S. pombe RAD3 during eukaryotic evolution, the RAD3 homolog gene was isolated by screening of genomic DNA library. The isolated gene was designated as HRD3 (homolog of RAD3 gene). Southern blot analysis confirmed that S. pombe chromosome contains the same DNA as HRD3 gene and this gene exists as a single copy in S. pombe. The transcript of 2.8 kb was detected by Northern blot analysis, The level of transcripts increased by ultraviolet (UV) irradiation, indicating that HRD3 is one of the UV-inducible genes in S. pombe. Furthermore, the predicted partial sequence of HRD3 protein has 60％ identity to S. cerevisiae RAD3 gene. This homology was particularly striking in the regions identified as being conserved in a group of DNA helicases. Gene deletion experiments indicate that the HRD3 gene is essential for viability and DNA repair function. These observations suggest evolutionary conservation of other protein components with which HRD3 might interact in mediating its DNA repair and viability functions.

• Animal cells and systems
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• v.10 no.4
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• pp.227-231
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• 2006

Micro-deletions at specific loci of the Y chromosome have been observed frequently in male infertility patients, suggesting that genes in these regions are involved in male germ cell development. DAZ is a representative male infertility gene at the AZFc locus of the Y chromosome. Since DAZ contains an RNA binding motif along with so-called a DAZ domain, it was proposed to participate in RNA metabolism during spermatogenesis. A mouse gene homologous to the human DAZ gene has been cloned and named Dazl (DAZlike). Dazl is autosomal and expressed in the testis and also at a low level in the ovary. Male mice homozygous for the Dazl null allele have small testes with a few spermatogonia and almost complete absence of germ cells beyond the spermatogonial stage, suggesting the requirement of Dazl for entry or progression through meiosis. However, its exact cellular functions have not been understood yet. In order to investigate cellular functions of Dazl, we decided to isolate candidate interacting protein genes of the mouse Dazl, using yeast two-hybrid screening. A number of candidate Dazlinteracting proteins have been isolated, such as Bprp, Acf, Hgs, Murr1, Nbak3 and Ranbp9, but dynein light chain 1 (Dlc1) was most predominant. A strong interaction of Dazl with Dlc1 suggests that Dazl might function as an mRNA adaptor to the dynein motor complex.

• Molecules and Cells
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• v.23 no.3
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• pp.357-362
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• 2007

There is an increasing demand for high throughput (HTP) methods for gene analysis on a genome-wide scale. However, the current repertoire of HTP detection methodologies allows only a limited range of cellular phenotypes to be studied. We have constructed two HTP-optimized expression vectors generated from the red fluorescent reporter protein (RFP) gene. These vectors produce RFP-tagged target proteins in a multiple expression system using gateway cloning technology (GCT). The RFP tag was fused with the cloned genes, thereby allowing us localize the expressed proteins in mammalian cells. The effectiveness of the vectors was evaluated using an HTP-screening system. Sixty representative human C2 domains were tagged with RFP and overexpressed in HiB5 neuronal progenitor cells, and we studied in detail two C2 domains that promoted the neuronal differentiation of HiB5 cells. Our results show that the two vectors developed in this study are useful for functional gene analysis using an HTP-screening system on a genome-wide scale.

• BMB Reports
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• v.39 no.1
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• pp.61-67
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• 2006

Molecular co-suppression phenomena are important to consider in transgene experiments. Embryogenic cells were obtained from immature cotyledons and engineered with two different gene constructs (pHV and pHVS) through particle bombardment. Both constructs contain a gene conferring resistance to hygromycin (hpt) as a selective marker and a modified glycinin (11S globulin) gene (V3-1) as a target. sGFP(S65T) as a reporter gene was, however, inserted into the flanking region of the V3-1 gene (pHVS). Fluorescence microscopic screening after the selection of hygromycin, identified clearly the expression of sGFP(S65T) in the transformed soybean embryos bombarded with the pHVS construct. Stable integration of the transgenes was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Seeds of transgenic plants obtained from the pHV construct frequently lacked an accumulation of endogenous glycinin, which is encoded by homologous genes to the target gene V3-1. Most of the transgenic plants expressing sGFP(S65T) showed highly accumulation of glycinin. The expression of sGFP(S65T) and V3-1 inherits into the next generations. sGFP(S65T) as a reporter gene may be useful to increase the transformation efficiency of transgenic soybean with avoiding gene co-suppression.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.600-610
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• 2008

A cancer-associated antigen gene (CAGE) was identified by serological analysis of a recombinant cDNA expression library (SEREX). The gene was identified by screening cDNA expression libraries of human testis and gastric cancer cell lines with sera from patients with gastric cancer. CAGE was found to contain a D-E-A-D box domain and encodes a putative protein of 630 amino acids with possible helicase activity. The CAGE gene is widely expressed in various cancer tissues and cancer cell lines. Demethylation plays a role in the activation of CAGE in certain cancer cell lines where the gene is not expressed. The functional roles of CAGE in tumorigenesis, the molecular mechanisms of CAGE expression, and cell motility are also discussed.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.69-73
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• 1990

As a part of the study to elucidate the mechanism by which transcription of LDH A-gene is regulated by cAMP, we aimed to isolated rat LDH A gene and characterize cAMP-reponsive element (CRE). We have screened $1.2{\times}10^6$ recombinant phages of rat Charon 4A genomic library and isolated 33 positive clones among which we identified 12 different LDH A gene-related clones. By the results of restriction enzyme mapping, Southern blotting, and nucleotide sequence analyses, we concluded that the 12 LDH A gene-related clones were intronless and frequently mutated LDH A-pseudogenes. In this report, we present the characteristic features of the 12 rat liver LDH A-pseudogenes.