• Genomics & Informatics
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• 제1권2호
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• pp.94-100
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• 2003

Motivation: Many have observed a nonlinear relationship between the signal intensity and the transcript abundance in microarray data. The first step in analyzing the data is to normalize it properly, and this should include a correction for the nonlinearity. The commonly used linear normalization schemes do not address this problem. Results: Nonlinearity is present in both cDNA and oligonucleotide arrays, but we concentrate on the latter in this paper. Across a set of chips, we identify those genes whose within-chip ranks are relatively constant compared to other genes of similar intensity. For each gene, we compute the sum of the squares of the differences in its within-chip ranks between every pair of chips as our statistic and we select a small fraction of the genes with the minimal changes in ranks at each intensity level. These genes are most likely to be non-differentially expressed and are subsequently used in the normalization procedure. This method is a generalization of the rank-invariant normalization (Li and Wong, 2001), using all available chips rather than two at a time to gather more information, while using the chip that is least likely to be affected by nonlinear effects as the reference chip. The assumption in our method is that there are at least a small number of non­differentially expressed genes across the intensity range. The normalized expression values can be substantially different from the unnormalized values and may result in altered down-stream analysis.

• 한국환경과학회지
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• 제20권4호
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• pp.551-554
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• 2011

The production of the sharp-toothed eel by commercial catch off waters of Korea is annually declined after 1978. This study was carried out to obtain the stock management of the sharp-toothed eel using the PCR-aided RFLP method. The mtDNA COI gene was amplified using species-specific primers and PCR product was observed to 700 bp. Amplified DNA fragments were treated with six kinds of restriction enzymes (BaeHI, EcoRI, PstI, Ksp22, HinfI and HaeIII). The treatment of HaeIII showed a distinct PCR product between Yeosu/Jinhae/Jeju/Goseoung and Jangheung/Haenam populations that were observed from 300 to 400 bp in reference to 100 bp molecular marker. However, DNA fragment within populations had an identical pattern. The phylogenetic homology is 82% between two populations inferred from RFLP PCR product pattern using NTsysPC ver. 2.1. The use of HaeIII plays an important role in discriminating populations. It is thought that adults after over-wintering in the southern part of Jeju migrate to the Yeosu, Jinhae and Goseoung regions to spawn instead of to southwestern waters. Individuals within populations showed a relatively active genetic mixing and migration regardless of geography. However, the genetic ancestor of Jangheung and Haenam populations is appeared to be more adjacent to China or Japan than Jeju.

• Asian-Australasian Journal of Animal Sciences
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• 제15권2호
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• pp.179-183
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• 2002

The fragment in intron I of FSH-${\beta}$ gene was amplified by PCR. According to the polymorphism, we analyzed the distribution of FSH-${\beta}$ retroposon in different pig breeds; its inheritance pattern in Large White${\times}$Meishan reference family; and the association of FSH-${\beta}$ retroposon with litter size, female reproductive organs measurement, ultrasonic backfat and other traits. The results showed that almost each Chinese indigenous pig had the retroposon, while foreign pig breeds rarely had; the frequencies of porcine FSH-${\beta}$ retroposon were strongly associated with breeds (p<0.01); the pattern of inheritance was consistent with Mendelian fashion; total number born (TNB) and number born alive (NBA) were increased per FSH-${\beta}$ retroposon (p<0.01) with additive effects of 1.2-1.8 and 1.4-1.8 pigs/litter, respectively; between the FSH-${\beta}$ retroposon carriers and non-carriers, there was an insignificant difference in the measurement of female reproductive organs, body weight at birth, backfat thickness, loin meat height, lean meat percentage, teat number, days to 100 kg, and average daily gain.

• Animal cells and systems
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• 제4권1호
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• pp.39-44
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• 2000

To assess the genetic diversity and population structure of Korean K. borealis, allozyme analysis was performed. The average genetic variability of Korean K. borealis populations was %P=13.2, Ho=0.048, and He=0.045. This value was the lowest in comparison with other Korean amphibian species studied. Also, the value was much lower than that of a reference population from Chinese K. borealis (%P=50, Ho=0.125, He=0.172). Wright's F-statistics showed that Korean K. borealis has distinctly low level of gene flow among regional populations (F$_{ST}$=0.339, Nm=0.487) in comparison with other Korean amphibian species studied. However, the average level of genetic divergence among Korean K. borealis populations was moderate (Nei's D=0.020). Therefore, it appeared that low levels of genetic diversity (He=0.045) and gene flow (Nm=0.487) among regional populations ave probably due to the results of decreasing population size and patchy distribution of this species in Korea.

• Food Science and Biotechnology
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• 제18권3호
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• pp.694-699
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• 2009

A multiplex polymerase chain reaction (PCR) method was developed for the detection of 4 events of genetically modified (GM) soybean. The event-specific primers were designed from 4 events of GM soybean (RRS, A2704-12, DP356043-5, and MON89788). The lectin was used as an endogenous reference gene of soybean in the PCR detection. The primer pair YjLec-4-F/R producing 100 bp amplicon was used to amplify the lectin gene and no amplified product was observed in any of the 9 different plants used as templates. This multiplex PCR method allowed for the detection of event-specific targets in a genomic DNA mixture of up to 1% GM soybean mixture containing RRS, A2704-12, DP356043-5, and MON89788. In this study, 20 soybean products obtained from commercial food markets were analyzed by the multiplex PCR. As a result, 6 samples contained RRS. These results indicate that this multiplex PCR method could be a useful tool for monitoring GM soybean.

• Journal of Microbiology and Biotechnology
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• 제16권4호
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• pp.543-549
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• 2006

DNA microarray was used to study the transcription profiling of Escherichia coli adapting to acetate as a sole carbon source. Bacteria grown in glucose minimal media were used as a reference. The dynamic expression levels of 3,497 genes were monitored at seven time points during this adaptation. Among the central metabolic genes, the glycolytic and glucose phosphotransferase genes were repressed as the bacteria entered stationary phase, whereas the glyoxylate pathway, TCA cycle, and gluconeogenic genes were induced. Distinct induction or repression patterns were recognized among different pathway genes. For example, the repression of glycolytic genes and the induction of gluconeogenic ones started immediately after glucose was depleted. On the other hand, the regulation of the pentose phosphate pathway genes and glyoxylate genes gradually responded to the glucose depletion or was more related to growth in acetate. When the whole genome was considered, many of the CRP, FadR, and Cra regulons were immediately responsive to the glucose depletion, whereas the $\sigma^s$, Lrp, and IHF regulons were gradually responsive to the glucose depletion. The expression profiling also provided differential regulations between isoenzymes; for example, malic enzymes A (sfcA) and B (maeB). The expression profiles of three genes were confirmed with RT-PCR.

• Parasites, Hosts and Diseases
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• 제60권4호
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• pp.273-279
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• 2022

Laelapinae mites are involved in transmission of microbial diseases between wildlife and humans, with an impact on public health. In this study, 5 mite members in the subfamily Laelapinae (laelapin mites; LM) were morphologically identified by light microscopy, and the phylogenetic relationship of LM was analyzed in combination with the sequence information of part of the LM cytochrome oxidase subunit I (cox1) gene. The morphological identification revealed that 5 mites belonged to the genera Laelaps and Haemolaelaps, respectively. Sequence analysis showed that the ratio of nonsynonymous mutation rate to synonymous mutation rate of LM was less than 1, indicating that the LM cox1 gene had undergone purifying selection. Phylogenetic analysis showed that the Laelapinae is a monophyletic group. The genera Haemolaelaps and Hyperlaelaps did not separated into distinct clades but clustered together with species of the genus Laelaps. Our morphological and molecular analyses to describe the phylogenetic relationships among different genera and species of Laelapinae provide a reference for the improvement and revision of the LM taxonomy system.

• Genomics & Informatics
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• 제19권3호
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• pp.34.1-34.6
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• 2021

Digital PCR (dPCR) is the third-generation PCR that enables real-time absolute quantification without reference materials. Recently, global diagnosis companies have developed new dPCR equipment. In line with the development, the Lab On An Array (LOAA) dPCR analyzer (Optolane) was launched last year. The LOAA dPCR is a semiconductor chip-based separation PCR type equipment. The LOAA dPCR includes Micro Electro Mechanical System that can be injected by partitioning the target gene into 56 to 20,000 wells. The amount of target gene per wells is digitized to 0 or 1 as the number of well gradually increases to 20,000 wells because its principle follows Poisson distribution, which allows the LOAA dPCR to perform precise absolute quantification. LOAA determined region of interest first prior to dPCR operation. To exclude invalid wells for the quantification, the LOAA dPCR has applied various filtering methods using brightness, slope, baseline, and noise filters. As the coronavirus disease 2019 has now spread around the world, needs for diagnostic equipment of point of care testing (POCT) are increasing. The LOAA dPCR is expected to be suitable for POCT diagnosis due to its compact size and high accuracy. Here, we describe the quantitative principle of the LOAA dPCR and suggest that it can be applied to various fields.

• Journal of Plant Biotechnology
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• 제42권4호
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• pp.326-335
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• 2015

감귤은 전 세계적으로 가장 많이 생산되는 주요 과수작물이고 비타민 C와 구연산 및 감귤 고유의 플라보노이드를 비롯한 다양한 기능성 성분으로 인해 건강 기능성 식품 소재로도 각광받고 있다. 그러나 긴 유년기와 배우체 불임, 주심배 발생 및 고도의 유전적 잡종성 등 감귤 특유의 생식생물학적 특성으로 인해 교배를 통한 전통 육종의 품종개발에 있어서는 가장 어려운 작물에 속한다. 지구 온난화, 소비자 욕구 변화 등으로 인해 고품질 감귤의 안정적 생산과 품종 다양화를 위한 체계적 육종 프로그램의 도입이 시급한 실정이다. 감귤에서도 분자 육종 프로그램을 통한 품종 육성을 위해 세계적으로 가장 많이 재배되는 스위트 오렌지와 클레멘타인 만다린에 대한 고품질 표준 유전체 정보가 최근에 확보되었다. 표준유전체 서열을 기반으로 다양한 품종 및 교배집단들에 대한 유전체 해독, 비교유전체 분석, GBS 등을 통해 형질연관 마커 발굴, 유전자 기능 연구 등이 이루어질 것으로 전망된다. 아울러 다양한 전사체 분석이 이루어지고 있으며, 유전자 기능 및 유전자 co-expression 네트워크의 이해를 증진할 수 있을 것이다. 유전체 및 전사체 분석을 통해 확보한 대규모 SNP, InDel 및 SSR의 다형성 분자마커 big data를 이용한 고밀도 연관 및 물리 지도 작성이 이루어지고 있고, 궁극적으로 통합지도 작성이 이루어지게 될 것이다. 이를 통해 가까운 장래에 감귤 특이 주요 농업형질 연관 유전자의 정확도 높은 map-based 클로닝 및 빠르고 효율적인 분자표지 선발육종이 이루어질 것이다.

• 한국환경생태학회지
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• 제28권5호
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• pp.523-530
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• 2014

2011년 6월 28일에 파주시 조리읍 장곡리 인근 도로에서 두부쪽이 손상되고, 해당연도에 태어난 맹금류 어린새를 발견하였고, 이를 DNA 바코드 기법으로 동정하였다. Mitochondrial DNA(mtDNA) cytochrome c oxidase I(COI) 유전자의 695bp 절편을 중합효소연쇄반응(polymerase chain reaction, PCR)으로 증폭하고 염기서열을 결정하였다. 결정된 염기서열을 BOLD systems과 NCBI의 BLAST에서 유사도 분석을 수행한 결과 총 5개체의 왕새매가 검색되었고, 염기서열의 동일성은 100%로 조사되었다. 또한, DNA 분자성판별 결과는 해당 개체가 암컷임을 나타내었다. 이러한 결과는 경기도 파주에서 1968년 이후 43년만에 왕새매의 번식이 확인된 중요한 정보로, 향후 광역야생동물구조센터는 야생동물의 사체 수거 시 인근 기탁등록보존기관과 연계하여 DNA시료를 확보하고 보다 정확한 종동정과 성판별 정보를 기록하는 등의 체계적인 관리시스템이 필요할 것으로 사료된다. 또한 이렇게 확보한 왕새매의 DNA 시료와 DNA 바코드 COI 유전자 서열은 유사종 연구의 참조표본(reference standard)로 이용될 수 있을 것이다.