• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.408-413
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• 2008

Rice blast resistance is considered one of the most important traits in rice breeding and the disease, caused by Magnaporthe grisea Barr, has brought significant crop losses annually. Moreover, breakdown of resistance normally occurs in two to five years after cultivar release, thus a more durable resistance is needed for better control of this disease. We developed a new variety, Keumo3, which showed strong resistance to leaf blast. It was tested in 2003 to 2007 at fourteen blast nursery sites covering entire rice-growing regions of South Korea. It showed resistance reactions in 12 regions and moderate in 2 regions without showing susceptible reactions. Durability test by sequential planting method indicated that this variety had better resistance. Results showed that Keumo3 was incompatible against 19 blast isolates with the exception of KI101 by artificial inoculation. To understand the genetic control of blast resistance in rice cultivar Keumo3 and facilitate its utilization, recombinant inbred lines (RIL) consisting of 290 F5 lines derived from Akidagomachi/Keumo3 were analyzed and genotyped with Pizt InDel marker zt56591. The recombination value between the marker allele of zt56591 and bioassay data of blast nursery test was 1.1%. These results indicated that MAS can be applied in selecting breeding populations for blast resistance using zt56591 as DNA marker.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.857-864
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• 2018

Previous studies have not detected transcripts of the gene encoding anthocyanidin synthase (ANS) in white pomegranates (Punica granatum L.) and suggest that a large-sized insertion in the coding region of the ANS gene might be the causal mutation. To elucidate the identity of the putative insertion, 3887-bp 5' and 3392-bp 3' partial sequences of the insertion site were obtained by genome walking and a gene coding for an expansin-like protein was identified in these genome-walked sequences. An identical protein (GenBank accession OWM71963) isolated from pomegranate was identified from BLAST search. Based on information of OWM71963, a 5.8-Mb scaffold sequence with genes coding for the expansin-like protein and ANS were identified. The scaffold sequence assembled from a red pomegranate cultivar also contained all genome-walked sequences. Analysis of positions and orientations of these genes and genome-walked sequences revealed that the 27,786-bp region, including the 88-bp 5' partial sequences of the ANS gene, might be translocated into an approximately 22-kb upstream region in an inverted orientation. Borders of the translocated region were confirmed by PCR amplification and sequencing. Based on the translocation mutation, a simple PCR codominant marker was developed for efficient genotyping of the ANS gene. This molecular marker could serve as a useful tool for selecting desirable plants at young seedling stages in pomegranate breeding programs.

• Molecules and Cells
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• v.24 no.1
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• pp.83-94
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• 2007

During monocarpic senescence in higher plants, functional stay-green delays leaf yellowing, maintaining photosynthetic competence, whereas nonfunctional stay-green retains leaf greenness without sustaining photosynthetic activity. Thus, functional stay-green is considered a beneficial trait that can increase grain yield in cereal crops. A stay-green japonica rice 'SNU-SG1' had a good seed-setting rate and grain yield, indicating the presence of a functional stay-green genotype. SNU-SG1 was crossed with two regular cultivars to determine the inheritance mode and identify major QTLs conferring stay-green in SNU-SG1. For QTL analysis, linkage maps with 100 and 116 DNA marker loci were constructed using selective genotyping with $F_2$ and RIL (recombinant inbred line) populations, respectively. Molecular marker-based QTL analyses with both populations revealed that the functional stay-green phenotype of SNU-SG1 is regulated by several major QTLs accounting for a large portion of the genetic variation. Three main-effect QTLs located on chromosomes 7 and 9 were detected in both populations and a number of epistatic-effect QTLs were also found. The amount of variation explained by several digenic interactions was larger than that explained by main-effect QTLs. Two main-effect QTLs on chromosome 9 can be considered the target loci that most influence the functional stay-green in SNU-SG1. The functional stay-green QTLs may help develop low-input high-yielding rice cultivars by QTL-marker-assisted breeding with SNU-SG1.

• Korean Journal of Breeding Science
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• v.43 no.2
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• pp.103-114
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• 2011

In recent years, genomic resources and information have accumulated at an ever increasing pace, in many plant species, through whole genome sequencing, large scale analysis of transcriptomes, DNA markers and functional studies of individual genes. Well-characterized species within key plant taxa, co-called "model systems", have played a pivotal role in nucleating the accumulation of genomic information and databases, thereby providing the basis for comparative genomic studies. In addition, recent advances to "Next Generation" sequencing technologies have propelled a new wave of genomics, enabling rapid, low cost analysis of numerous genomes, and the accumulation of genetic diversity data for large numbers of accessions within individual species. The resulting wealth of genomic information provides an opportunity to discern evolutionary processes that have impacted genome structure and the function of genes, using the tools of comparative analysis. Comparative genomics provides a platform to translate information from model species to crops, and to relate knowledge of genome function among crop species. Ultimately, the resulting knowledge will accelerate the development of more efficient breeding strategies through the identification of trait-associated orthologous genes and next generation functional gene-based markers.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.776-782
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• 2012

Marbling (intramuscular fat) is the most economically important meat quality trait in Hanwoo (Korean cattle). The endothelial differentiation G-protein coupled receptor 1 (EDG1) gene, involved in blood vessel formation, is located within the genomic region of a quantitative trait locus (QTL) for marbling on bovine chromosome 3. Thus, the EDG1 gene can be considered as a positional and functional candidate gene for meat quality in beef cattle. This study aimed to identify single nucleotide polymorphisms (SNPs) in the EDG1 gene and to evaluate their associations with carcass traits in Hanwoo population. We have sequenced a fragment of 5'-UTR of the EDG1 gene and identified one SNP. Genotyping of the g.166A>G SNP marker was carried out using PCR-RFLP analysis in 309 Hanwoo steers in order to evaluate their association with carcass traits. The g.166A>G SNP marker showed a significant effect on the marbling score. Animals with the GG genotype had higher marbling score compared with AA and AG genotypes (p<0.05). This SNP marker also showed a significant additive effects for the marbling score (p<0.05). These results suggest that the EDG1 gene can be used as a molecular marker for DNA marker-assisted selection in order to increase the levels of the marbling score in Hanwoo.

• Asia Pacific Journal of Corpus Research
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• v.1 no.2
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• pp.27-39
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• 2020

This paper examines the frequency and distribution of the so-called "non-discourse marker functions" of so in essay writings produced by 200 L1 English speakers and 1,300 EFL learners in China, Japan, Korea, and Taiwan. Based on the data drawn from the International Corpus Network of Asian Learners of English, this study compares EFL learners and L1 English speakers' uses of so, identifying four grammatical uses, as (1) an adverb, (2) part of a fixed phrase, (3) a pro-form, and (4) a conjunction phrase specifying purpose. This study aims to show the wide variability among EFL learners with different L1s, identifying the tendency of usage both common among and specific to the sub-groups of EFL learners. The findings suggest that the learners demonstrate patterns distinctively different from those of L1 English speakers, indicating an underuse of so as a marker expressing "purpose" and an overuse as part of fixed phrases. Compared to L1 English speakers, the learners also tend to overuse so in the discourse marker functions, regardless of their L1s. The study proposes pedagogical implications focusing on discourse flow and diachronic aspects of so in order to understand its multifunctionality, although the latter is primarily suggested for advanced learners.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.172-177
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• 2007

Thyroid hormones play an important role in regulating metabolism and can affect homeostasis of fat depots. The gene encoding thyroglobulin (TG), producing the precursor for thyroid hormones, has been proposed as a positional and functional candidate gene for a QTL with an effect on fat deposition. The SNP occurs in the 5' promoter region of the TG gene and is widely used in marker assisted selection (MAS) programs to improve the predictability of marbling level and eating quality in beef cattle. In this study, we identified three SNPs at the 5' promoter region of the TG gene in Korean cattle. Of the three SNPs identified in TG gene, the C257T and A335G were previously unreported new SNPs. The sequence data were submitted to GenBank (GenBank accession number: AY615525). The previously reported C422T SNP showed three genotypes, CC, CT and TT, by digestion with the restriction enzyme MflI using the PCR-RFLP method. A new allelic variant corresponding to the C${\rightarrow}$T and A${\rightarrow}$G mutations at positions 257 and 335, respectively, could be detected by the SSCP analysis. The gene-specific SNP marker association analysis indicated that the C422T SNP marker was significantly associated (p<0.05) with marbling score. Animals with the CC and CT genotypes had higher marbling score than those with the TT genotype. Results from this study suggest that TG gene-specific SNP may be a useful marker for meat quality traits in future MAS programs in Korean cattle.

• Korean Journal of Poultry Science
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• v.28 no.2
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• pp.107-123
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• 2001

• Cross-Cultural Studies
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• v.25
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• pp.649-678
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• 2011

The purpose of this work is to explain categorial correlations between indirect evidentiality and epistemic modality on the basis of semantic, pragmatic usages of Russian so-called non-specialized lexical markers of evidentiality, such as kazhetsja, naverno, vidimo, poxozhe, dolzhno byt' etc. To do this, firstly I concentrated on the parameter of internal functional variation of a given parenthetic word. Secondly, I approached this topic from a typological perspective. Thirdly, I accepted Sweeter(1990)'s methodological assumption that etymological prototype of a given word plays a great role in grammatical, semantic, pragmatic changes. As a result, I could postulate general tendencies of grammaticalizations (or semantic, pragmatic, funtional changes) in the direction from epistemic modality to indirect evidentialty, which consists of inferentives, presumptives, and quotatives. For example, such a parenthetic word as kazhetsja can functions not only as a marker of epistemic modality of uncertainty, but also as inferentives. Besides, it is very interesting that this word lately has started to function as quotatives, too. This kind of functional variations are very characteristic in these spheres.

• The Korean Journal of Food And Nutrition
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• v.36 no.2
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• pp.93-102
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• 2023

Centella asiatica (C. asiatica) has been widely used in food, cosmetics, and pharmaceutical industry as a functional material. In a previous study, we have investigated not only pharmacological effects such as antioxidative and anti-inflammatory effects, but also analyzed various functional ingredients. In this study, triterpenoids were analyzed using HPLC-DAD to determine marker compounds among functional ingredients. When triterpenoids were analyzed, asiaticoside from C. asiatica was determined as an optimal marker compound. Next, specificity, linearity, limited of detection (LOD), limited of quantification (LOQ), precision, accuracy, and range were evaluated using HPLC-DAD to determine asiaticoside contents in C. asiatica juice and extracts. The specificity was elucidated by chromatogram and retention time using an established analytical method. The coefficient of correlation obtained was 0.9996. LOD was 4.99 ㎍/mL and LOQ was 15.12 ㎍/mL. Intra- and inter-day precision of asiaticoside were determined to be 0.48~1.68% and 0.08~1.09%, respectively. Furthermore, the recovery rate of asiaticoside was 98.88% and the analytical range of Field-70E was determined to be 0.625~10 mg/mL. As a results of evaluating ABTS, DPPH, and FRAP antioxidative effect, Field-70E showed potent antioxidant activities. Results of this study could be used as basic data for quality standardization of C. astiatica juice and extracts.