• Molecules and Cells
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• v.26 no.3
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• pp.278-284
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• 2008

An open reading frame, designated GerGTII and located downstream of the polyketide synthase genes, has been identified as a chalcosyltransferase by sequence analysis in the dihydrochalcomycin biosynthetic gene cluster of Streptomyces sp. KCTC 0041BP. The deduced product of gerGTII is similar to several glycosyltransferases, authentic and putative, and it displays a consensus sequence motif that appears to be characteristic of a sub-group of these enzymes. Specific disruption of gerGTII within the S. sp. KCTC 0041BP genome by insertional in-frame deletion method, resulted complete abolishment of dihydrochalcomycin and got the 20-O-mycinosyl-dihydrochalconolide as intermediate product in dihydrochalcomycin biosynthesis which was confirmed by electron spray ionization-mass spectrometry and liquid chromatography-mass spectrometry. Dihydrochalcomycin also was recovered after complementation of gerGTII.

• Journal of Plant Biology
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• v.32 no.2
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• pp.67-78
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• 1989

Hybridization of DNA isolated from leaves of Russet Burbank potato with tomato cDNA as a probe revealed the presence of about ten inhibitor 1 genes in the genome. Screening of a genomic library of Russet Burbank potato resulted in isolation of seven different genomic clones carrying inhibitor I genes. One of the genomic clones, clone 2, contained two EcoRI fragments of 3.4 and 1.8 kb in size, respectively, which were hybridized with the probe. The nucleotide sequence of parts of the hybridizing EcoRI fragments revealed that they contain a complete gene which codes for an open reading frame of 107 amino acids. It is interrupted by two intervening sequences of 502 and 493 bp, situated at the positions of codons 17 and 43, respectively, of the open reading frame. Putative regulatory sequences, TATAAA and CCACT, were found at the 5' flanking region. In addition, a copy of a 100 bp repeat found at a tomato inhibitor I gene was identified.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.135-135
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• 2005

• Genomics & Informatics
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• v.7 no.1
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• pp.1-12
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• 2009

An alternative way of constructing ancestral graphs, which is different from the coalescent-based approach, is proposed using population linkage disequilibrium (LD) data. The main difference from the existing method is the construction of the ancestral graphs based on variants instead of individual sequences. Therefore, the key of the proposed method is to use the order of allele ages in the graphs. Distinct from the previous age-estimation methods, allele ages are estimated from full haplotype information by examining the number of generations from the initial complete LD to the current decayed state for each two variants depending on the direction of LD decay between variants. Using a simple algorithmic procedure, an ancestral graph can be derived from the expected allele ages and current LD decay status. This method is different in many ways from previous methods, and, with further improvement, it might be a good replacement for the current approaches.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.22-22
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• 2001

At the eukaryotic replication fork, discontinuous synthesis of lagging strand DNA gives rise to Okazaki fragments carrying ribonucleotides derived from the primer RNA at their 5' ends. Efficient removal of these ribonucleotides is vital for maintaining genome integrity. In this report we show that the endonucleases Dna2 and Fen1 act sequentially to facilitate the complete removal of the primer RNA.(omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.11a
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• pp.49-49
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• 2005

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.128-135
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• 2008

Herbicide resistance is the most common trait being tested and thus herbicide?resistant genetically modified plants are now the most widely cultivated worldwide. Here we developed herbicide?resistant transgenic Agrostis mongolica Roshev. by employing an efficient Agrobacterium?mediated transformation procedure with 25.2% of transformation efficiency. The identification and employment of regenerable and reproducible type of callus was one of the most critical factors to ensure success in this study. PCR analysis confirmed that the bar transgene was integrated into the genome of transgenic plants. The expression of 35S?bar gene was confirmed by Northern blot analysis. The transgenic plants showed complete resistance to herbicide, indicating that the bar gene is functional in transgenic plants.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.889-897
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• 2018

Currently, there is a lack of genetic markers capable of effectively detecting polymorphisms in Clematis. Therefore, we developed new markers to investigate inter- and intraspecific diversity in Clematis. Based on the complete chloroplast genome of Clematis terniflora, simple sequence repeats were explored and primer pairs were designed for all ten adequate repeat regions (cpSSRs), which were tested in 43 individuals of 11 Clematis species. In addition, the nuclear ITS region was sequenced in 11 Clematis species. Seven cpSSR loci were found to be polymorphic in the genus and serve as markers that can distinguish different species and be used in different genetic analyses, including cultivar identification to assist the breeding of new ornamental cultivars.

• Genomics & Informatics
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• v.10 no.2
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• pp.117-122
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• 2012

A sample size with sufficient statistical power is critical to the success of genetic association studies to detect causal genes of human complex diseases. Genome-wide association studies require much larger sample sizes to achieve an adequate statistical power. We estimated the statistical power with increasing numbers of markers analyzed and compared the sample sizes that were required in case-control studies and case-parent studies. We computed the effective sample size and statistical power using Genetic Power Calculator. An analysis using a larger number of markers requires a larger sample size. Testing a single-nucleotide polymorphism (SNP) marker requires 248 cases, while testing 500,000 SNPs and 1 million markers requires 1,206 cases and 1,255 cases, respectively, under the assumption of an odds ratio of 2, 5% disease prevalence, 5% minor allele frequency, complete linkage disequilibrium (LD), 1:1 case/control ratio, and a 5% error rate in an allelic test. Under a dominant model, a smaller sample size is required to achieve 80% power than other genetic models. We found that a much lower sample size was required with a strong effect size, common SNP, and increased LD. In addition, studying a common disease in a case-control study of a 1:4 case-control ratio is one way to achieve higher statistical power. We also found that case-parent studies require more samples than case-control studies. Although we have not covered all plausible cases in study design, the estimates of sample size and statistical power computed under various assumptions in this study may be useful to determine the sample size in designing a population-based genetic association study.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.139-148
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• 2010

A virus causing stunt, yellowing, severe mosaic, malformation symptoms on leaves and uneven development and malformation on fruits of zucchini was prevalent around Goseong, Gyeongsangnam-do, Korea. A survey conducted (2004) in the Goseong area revealed about 20% virus infection rate. The disease causative identified as Cucumber mosaic virus (CMV-Z1) was further characterized. The isolate induces mosaic symptoms on Cucumis sativus, while severe mosaic, stunt and malformation on C. pepo. Thin section analyses have shown that virus inclusions are formed in the cuticle layers as well as epidermal, parenchyma and collenchymas cells in virus-infected Nicotiana tabacum. CMV-Z1 isolate induced specific cytoplasmic inclusion bodies such as irregular clumps (IC), crystal (Cr) and irregular chloroplasts (ICh). IC was made up of virus particles interspersed with a darkly stained amorphous material and found both in the cytoplasm and vacuoles, whereas ICh and Cr were rarely found in the vacuoles. The genome of CMV-Z1 RNA-1 consists of 3359 nucleotide (nt) encoding 1a protein of 993 amino acids (aa). The CMV-Z1 RNA-2 was 3050 nt in length containing 2a (857 aa) and 2b (110 aa), while RNA-3 encoding 3a movement protein (279 aa) and coat protein (218 aa) was 2215 nt in length. Phylogenetic analyses of nucleotide sequences of CMV-Z1 isolate appeared it is more closely related to subgroup IA than to subgroup IB or II.