• Journal of Korean Society of Forest Science
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• v.18 no.1
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• pp.17-22
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• 1973

Using of zymography for identification of same clone of Pinus densiflora, the two year old needle leaves of 48 ramtes including 8 clones (6 ramets per clone) were collected in the clone bank which has been established on the near campus of Institute of Forest Genetics, Suwon, in 1962. All 8 bands are named from cathod to anode, G, H, K, M, N, Q, S and Y. Only CB-1 clone shows all bands, while KW-3 clone reveals only 5 bands. Other 6 clones were found 7 bands but the occurred frequencies of those bands are variable among those clones. Though the grafting stock are used various individuals grown seed propagation of P. densiflora, moreover, three stocks have been different species and that one has been P. rigida and two individuals have been P. koraiensis, the zymograms of the ramets belonging to the same clone reveals the identified patterns. The results show that the stocks for grafting have not been affected on the isoperoxidase patterns of their scions in P. densiflora. Among 48 ramets of 8 clones, 4 ramets are found the different isoperoxidase patterns from that of the remained rametes within same clone. Thus, it is conluded that zymography is useful for testing genuineness of the grafted clones of P. densiflora.

• BMB Reports
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• v.44 no.2
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• pp.113-117
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• 2011

Previous studies suggest that EphA7 plays a critical role in neural tube closure or cortical progenitor apoptosis. In this report, enhancer trap assay was used to modify various EphA7 BAC clones and screen a large genomic region spanning 570 kb downstream of the EphA7 gene. We found that the dorsal midline-specific EphA7 enhancer resides on the 457D20 EphA7 BAC clone and is localized to a 35 kb genomic region in between +345.7 kb to +379.8 kb downstream of the EphA7 transcription start site. Identification of the EphA7 BAC clone containing a long-range dorsal midline enhancer may constitute a useful tool for investigating the biological functions of EphA7 in vivo.

• Journal of Microbiology
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• v.42 no.1
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• pp.9-13
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• 2004

Culture-independent approaches, based on 16S rDNA sequences, are extensively used in modern microbial ecology. Sequencing of the clone library generated from environmental DNA has advantages over fingerprint-based methods, such as denaturing gradient gel electrophoresis, as it provides precise identification and quantification of the phylotypes present in samples. However, to date, no method exists for comparing multiple bacterial community structures using clone library sequences. In this study, an automated method to achieve this has been developed, by applying pair wise alignment, hierarchical clustering and principle component analysis. The method has been demonstrated to be successful in comparing samples from various environments. The program, named CommCluster, was written in JAVA, and is now freely available, at http://chunlab.snu.ac.kr/commcluster/.

• Journal of Life Science
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• v.8 no.3
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• pp.285-293
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• 1998

We have cloned an internal fragment of the putative transoisase gene of MLE in the silkworm, Bombyx mori, using PCR method with degenerative oligonucleotide primers designed to represent regions of amino acids encoding transposase. The resulting PCR clone, designed as BmoMAR, cords a partial ORF(152 a.a.) of MLE in which interrupted by five stop codons, and the sequence of its deduced amino acids showed 37% homology with Mos1, an active mariner, from Drosophila mauritiana. Furthermore, the BmoMAR exhibits nucleotide and amino acid homology with 59% and 37% from Apis mellifera and D. mauritiana 7.9 clone, respectively. This result strongly that a MLE is present in the genome of B. mori.

• Journal of Life Science
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• v.11 no.2
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• pp.83-86
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• 2001

The long terminal repeat (LTR) elements of human endogenous retrovirus (HERV) have been found to be coexpressed with genes located nearby. It has been suggested that the LTR elements have contributed to the genetic variation of human genome connected to various diseases. Recently, HERV-W family was identified in the cerebrospinal fluids and brains of individuals with schizophrenia. Using genomic DNAs derived from schizophrenia, we performed PCR amplification and identified six HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (87.7-99.5%) with HERV-W LTR (AF072500). Sequence analysis of the HERV-W LTR elements revealed that clone W-sch1 showed identical sequence with the AC003014 (PAC clone RP1-290B4) derived from human Xq23. Clone W-sch2 was closely related to the AC0072442 derived from human Y chromosome by phylogenetic analysis. Our data suggest that new HERV-W LTR elements in schizophrenia may be very useful for further studies to understand neuropsychiatric diseases.

• Parasites, Hosts and Diseases
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• v.37 no.4
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• pp.257-263
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• 1999

Identification of the genes responsible for the recovery of virulence in brain-passaged Acanthamoeba culbertsoni was attempted via mRNA differential display polymerase chain reaction (mRNA DD-PCR) analysis. In order to identify the regulatory changes in transcription of the virulence related genes by the brain passages, mRNA DD-PCR was performed which enabled the display of differentially transcribed mRNAs after the brain passages. Through mRNA DD-PCR analysis. 96 brain-passaged amoeba specific amplicons were observed and were screened to identify the amplicons that failed to amplify in the non-brain-passaged amoeba mRNAs. Out of the 96 brain-passaged amoeba specific amplicons, 12 turned out to be amplified only from the brain-passaged amoeba mRNAs by DNA slot blot hybridization. The clone, A289C, amplified with an arbitrary primer of UBC ＃289 and the oligo dT$_{11}$-C primer, revealed the highest homology (49.8％) to the amino acid sequences of UPD-galactose lipid transferase of Erwinia amylovora, which is known to act as an important virulence factor. The deduced amino acid sequences of an insert DNA in clone A289C were also revealed to be similar to cpsD, which is the essential gene for the expression of type III capsule in group B streptococcus. Upregulated expression of clone A289C was verified by RNA slot blot hybridization. Similar hydrophobicity values were also observed between A289C (at residues 47-66) and the AmsG gene of E. amylovora (at residues 286-305: transmembrane domains). This result suggested that the insert of clone A289C might play the same function as galactosyl transferase controlled by the AmsG gene in E. amylovora.a.

• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.330-337
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• 1987

Megagametophyte tissues from seeds of 45 loblolly pine clones were subjected to horizontal starch-gel electrophoresis. The resulting gels were tested for activity of five enzyme systems (GOT, SDH, PGM, MDH, and AP). Isozymes observed were under control of 11 loci. All 45 clones could be identified with unique genotypes at above 10 loci.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.13-22
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• 2002

To identify the differentially expressed genes at growth stage of Hanwoo, we constructed the subtractive cDNA library from loin mRNA of 12- and 24-month old Hanwoo by PCR-based subtraction. The fourteen genes were confirmed by sequencing and reverse northern blot analysis, and they were selected as candidate of putative genes differentially expressed at the growth stage of Hanwoo. Three subtracted cDNA fragments that expressed specific signal to cDNA probe for 6-month-old loin of Hanwoo were highly homologous to those of the genes encoding EPV 20, Ca2＋ATPase, and TCTP, respectively. The nine cDNA clones showed intense signal to cDNA probe from 12-month-old loin of Hanwoo, and highly homologus to those of genes encoding VCP, HSP 70, aldolase A, MSSK1, GM-2 activator protein, ryanodine receptor, acidic ribosomal phosphoprotein p1, ADP/ATP translocase, and UCP 2, respectively. Two subtracted cDNA clones that expressed specific signal to cDNA probes for 12- and 24-month-old loin of Hanwoo were detected. One of them was highly homologus to the gene encoding ferrochelatase and the other was highly homologus to the gene encoding ADRP.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.287-292
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• 2005

The cyanobacterial diversity was analyzed by restriction fragment length polymorphism (RFLP) of PCR-amplified rpcBA-Intergenic Spacer (IGS) genes and cpcBA-IGS gene sequencing with a sample collected at Chuso-ri in Daechung Reservoir on March 15, 2005, The Shannon-Weiner diversity index was 0.65, indicating that the cyanobacterial community structure was simple. PCR-RFLP profiles obtained were Phormidium spp. (58 clones), Anabaena spp. (14 clones), Microcystis spp. (4 clones), Spirulina sp. (1 clone) and uncultured cyanobacteria (2 clones). The PCR-RFLP of cpcBA-IGS revealed that Phormidium spp. and Anabaena spp. dominated in the invested sample. As a consequence, it seems that the analysis of functional genes such as cpcBA-IGS can be used for the species identification and community analysis of cyanobacteria.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.521-529
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• 2016

Extensive use of antibiotics over recent decades has led to bacterial resistance against antibiotics, including gentamicin, one of the most effective aminoglycosides. The emergence of resistance is problematic for hospitals, since gentamicin is an important broad-spectrum antibiotic for the control of bacterial pathogens in the clinic. Previous study to identify gentamicin resistance genes from environmental samples have been conducted using culture-dependent screening methods. To overcome these limitations, we employed a metagenome-based culture-independent protocol to identify gentamicin resistance genes. Through functional screening of metagenome libraries derived from soil samples, a fosmid clone was selected as it conferred strong gentamicin resistance. To identify a specific functioning gene conferring gentamicin resistance from a selected fosmid clone (35-40 kb), a shot-gun library was constructed and four shot-gun clones (2-3 kb) were selected. Further characterization of these clones revealed that they contained sequences similar to that of the RNA ligase, T4 rnlA that is known as a toxin gene. The overexpression of the rnlA-like gene in Escherichia coli increased gentamicin resistance, indicating that this toxin gene modulates this trait. The results of our metagenome library analysis suggest that the rnlA-like gene may represent a new class of gentamicin resistance genes in pathogenic bacteria. In addition, we demonstrate that the soil metagenome can provide an important resource for the identification of antibiotic resistance genes, which are valuable molecular targets in efforts to overcome antibiotic resistance.