• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.99-102
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• 2001

Recombinant Saccharomyces cerevisiae strains harboring various copy numbers of hirudin gene were developed to study dependency of hirudin expression level on its gene copy number. A linear relationship between the copy number of hirudin expression cassette and hirudin expression level was observed up to 10 copies. A double <5-integration vector truncated wi 디 1 the unnecessary bacterial genes before yeast transformation showed a four-fold increase in transformation efficiency and a 1.3-fold enhancement in hirudin expression level compared with a single <5 system. Gratuitous hirudin expression strain was developed by disrupting the GALl gene of S. cerevisiae. Glucose that was fed in a limited manner effectively supported cell growth and hi겨din expression by the gratuitous strain. Effects of methanol concentrations on hirudin production in recombinant Hansenula polymorpha were investigated in continuous and fed-batch cultures. At a steady-state of continuous culture, an optimum methanol concentration of 1.7 g/L was determined at a dilution rate of 0.18 $h^{-1}$ with 1.8 mg/L ${\cdot}$ h hirudin productivity.

• Korean Journal of Microbiology
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• v.29 no.2
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• pp.80-84
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• 1991

We cloned and expressed hepatitis B viral core antigen (HBcAg) gene in E. coli using $P_{L}$ promoter system. For optimal expression of the gene, we undertook the studies on the effects of the distance between Shine-Dalgarno (SD) sequence and start codon, copy number of repressor gene, induction temperature, and the stability of the core antigen. The results demonstrated that the induction at 37.deg.C was more efficient than at 42.deg.C, and the 11 base pairs (bp) distance between SD sequence and start codon of HBcAg gene was more efficient than the 15 bp distance in E. coli. The copy number of cI857 repressor gene did not influence on the expression of HBcAg, and the expression level of HBcAg in mutant type (low protease activity) and wild type strains was almost the same. The produced core antigen appeared to be HBcAg not HBeAg judged by two different radioimmunoassat (RIA) kits. This result suggested that the antigen was stable in E. coli.i.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.544-549
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• 1995

The alkaline elastase is an extracellular serine protease of the alkalophilic Bacillus strain Ya-B. To increase the gene copy number and the production level of the alkaline elastase Ya-B, we designed, on the B. subtilis chromosome, a gene amplification of the 10.6 kb repeating unit containing amyE, aleE (alkaline elastase Ya-B gene) and tmrB. The aleE was inserted between amyE and tmrB, and B. subtilis APT119 strain was transformed with this amyE-aleE-tmrB-junction region fragment. As a result, we succeeded in obtaining tunicamycin-resistant (Tm$^{r}$) transformants (Tf-1, Tf-2) in which the designed gene amplification of 10.6 kb occurred in chromosome. The transformants showed high productivity of $\alpha $-amylase and alkaline elastase Ya-B. The copy number of the repeating unit (amyE-aleE-tmrB) was estimated to be 25, but plasmid vector (pUC19) was not integrated. The amplified aleE of chromosome was more stable than that of plasmid in absence of antibiotics.

• Journal of Genetic Medicine
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• v.20 no.2
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• pp.46-51
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• 2023

Exonic copy number variation (CNV), involving deletions and duplications at the gene's exon level, presents challenges in detection due to their variable impact on gene function. The study delves into the complexities of identifying large CNVs and investigates less familiar but recurrent exonic CNVs, notably enriched in East Asian populations. Examining specific cases like DRC1, STX16, LAMA2, and CFTR highlights the clinical implications and prevalence of exonic CNVs in diverse populations. The review addresses diagnostic challenges, particularly for single exon alterations, advocating for a strategic, multi-method approach. Diagnostic methods, including multiplex ligation-dependent probe amplification, droplet digital PCR, and CNV screening using next-generation sequencing data, are discussed, with whole genome sequencing emerging as a powerful tool. The study underscores the crucial role of ethnic considerations in understanding specific CNV prevalence and ongoing efforts to unravel subtle variations. The ultimate goal is to advance rare disease diagnosis and treatment through ethnically-specific therapeutic interventions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.329-337
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• 2012

Considerable attention has been given to the accuracy of HER-2 testing and the correlation between the results of different testing methods. This interest reflects the growing importance of HER-2 status in the management of patients with breast cancer. In this study the detection of HER-2 gene and centromere 17 status was evaluated using dual-colour primed in situ labelling (PRINS) in comparison with fluorescence in situ hybridization (FISH). These two methods were evaluated on a series of 27 formalin fixed paraffin embedded breast carcinoma tumours, previously tested for protein overexpression by HercepTest (grouped into Hercep 1+/0, 2+ and 3+). HER-2 gene amplification (ratio${\geq}2.2$) by PRINS was found in 3:3, 6:21 and 0:3 in IHC 3+, 2+ and 1+/0 cases, respectively. Comparing FISH and IHC (immunohistochemistry), showed the same results as for PRINS and IHC. Chromosome 17 aneusomy was found in 10 of 21 IHC 2+ cases (47.6%), of which 1 (10%) showed hypodisomy (chromosome 17 copy number per cell${\leq}1.75$), 7 (70%) showed low polysomy (chromosome 17 copy number per cell=2.26 - 3.75) and 2 (20%) showed high polysomy (chromosome 17 copy number per cell ${\geq}3.76$). The overall concordance of detection of HER-2 gene amplification by FISH and PRINS was 100% (27:27). Furthermore, both the level of HER-2 amplification and copy number of CEN17 analysis results correlated well between the two methods. In conclusion, PRINS is a reliable, reproducible technique and in our opinion can be used as an additional test to determine HER-2 status in breast tumours.

• The KIPS Transactions:PartD
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• v.18D no.2
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• pp.89-100
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• 2011

The CNV (Copy Number Variation) which is one of the genetic structural variations in human genome is closely related with the function of gene. In particular, the genome-wide association studies for genetic diseased persons have been researched. However, there have been few studies which infer the genetic function of CNV with normal human. In this paper, we propose the analysis method to reveal the functional relationship between common CNV and genes without considering their genomic loci. To achieve that, we propose the data integration method for heterogeneity biological data and novel measurement which can calculate the correlation between common CNV and genes. To verify the significance of proposed method, we has experimented several verification tests with GO database. The result showed that the novel measurement had enough significance compared with random test and the proposed method could systematically produce the candidates of genetic function which have strong correlation with common CNV.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.87-90
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• 2001

BcGRl gene encoding cytosolic glutathione reductase of Chinese cabbage (Brassica campestris var. Pekinensis cv. Seoul) was placed under the control of the CaMV 35S promoter and introduced into tobacco (Nicotiana tabacum L. cv. Samsun) via Agrobacterium-mediated transformation. T$_{0}$ 32 independent plants transformed with BcGRl gene were selected with kanamycin and they were confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Northern blot analysis revealed that the constitutive expression of BcGRl gene and there was no relationship between the copy number of introduced gene and the levels of BcGRl transcripts.

• Genomics & Informatics
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• v.10 no.1
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• pp.65-67
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• 2012

We have discovered copy number variations (CNVs) in 3,578 Korean individuals with the Affymetrix Genome-Wide SNP array 5.0, and 4,003 copy number variation regions (CNVRs) were defined in a previous study. To explore the details of the variants easily in related studies, we built a database, cataloging the CNVs and related information. This system helps researchers browsing these variants with gene and structure variant annotations. Users can easily find specific regions with search options and verify them from system-integrated genome browsers with annotations.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1353-1358
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• 2005

A rapid and quantitative real-time PCR was developed to target the invasion A (invA) gene of Salmonella spp. We developed quantitative standard curves based on plasmids containing the invA gene. Based on these curves, we detected Salmonella spp. in artificially contaminated buffered peptone water (BPW) and milk samples. We were able to determine the invA gene copy number per ml of food samples, with the minimum detection limit of $4.1{\times}10^{3}$ copies/ml of BPW and $3.3{\times}10^{3}$ copies/ml of milk. When applied directly to detect and quantify Salmonella spp. in BPW and milk, the present real-time PCR assay was as sensitive as the plate count method; however, copy numbers were one to two logs higher than the colony-forming units obtained by the plate count methods. In the present work, the real-time PCR assay was shown to significantly reduce the total time necessary for the detection of Salmonella spp. in foods and to provide an important model for other foodborne pathogens.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.847-858
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• 2015

Bacillus amyloliquefaciens GR4-5 was isolated from the rhizosphere soil of Korean ginseng and displayed broad-spectrum suppression of ginseng root rot pathogens. The survivability of B. amyloliquefaciens GR4-5 in soil was investigated under three different conditions; indoor, outdoor - of which soil was put in 14 mL tube after treatment - and field environments. Soil samples were collected over a four-week period from three experimental designs, and assessed for 16S rRNA gene copy number by quantitative polymerase chain reaction (qPCR). In outdoor condition, the 16S rRNA gene copy number of Bacillus spp. was 8.35 log copies g $soil^{-1}$ immediately after the GR4-5 treatment. Two weeks later, the 16S rRNA gene copy number of Bacillus spp. (6.70 log copies g $soil^{-1}$) was similar to that of the control (6.38 log copies g $soil^{-1}$). In indoor condition, the 16S rRNA gene copy number of Bacillus spp. maintained in a certain level for a longer period than those in outdoor and field. The 16S rRNA gene copy number of Bacillus spp. in field experiment was reduced faster than that of outdoor condition. Our results show that B. amyloliquefaciens GR4-5 can survive in bulk soil for 1 week, indicating its potential use as a biocontrol agent following 7 day application intervals. This study presents that outdoor microcosm system design could be a useful method to assess easily the survivability of beneficial microorganisms.