• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.211-211
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• 2022

Amaranth is a nutritious and broadly adapted seed crop in high demand around the world. A preliminary approach for understanding the genetics of amaranth resources entails a morphologic characterization, which can provide the basis for breeding the first variety in Korea, leading to satisfying the needs of farmers and consumers. Therefore, this study aimed to evaluate the phenotypic characteristics of ten genetic amaranth accessions for the selection of outstanding accessions in terms of yield and grain quality. A randomized complete block design was used, with fifteen replications for each accession under field conditions. Five quantitative and three qualitative descriptors were evaluated with descriptive analysis. The results showed that the accessions with plant heights smaller than the average (>112.7 cm) presented lower yields and smaller seed sizes, thus decreasing the grain quality. The cluster analyses established groups of accessions with good yields (>30.1 g of seeds per plant) and stable morphological characteristics. Based on yield and morphological descriptors, the proposed selection index indicated four accessions as potential parents for amaranth breeding programs in Kora.

• IMMUNE NETWORK
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• v.23 no.1
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• pp.5.1-5.28
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• 2023

Th cell lineage determination and functional specialization are tightly linked to the activation of lineage-determining transcription factors (TFs) that bind cis-regulatory elements. These lineage-determining TFs act in concert with multiple layers of transcriptional regulators to alter the epigenetic landscape, including DNA methylation, histone modification and threedimensional chromosome architecture, in order to facilitate the specific Th gene expression programs that allow for phenotypic diversification. Accumulating evidence indicates that Th cell differentiation is not as rigid as classically held; rather, extensive phenotypic plasticity is an inherent feature of T cell lineages. Recent studies have begun to uncover the epigenetic programs that mechanistically govern T cell subset specification and immunological memory. Advances in next generation sequencing technologies have allowed global transcriptomic and epigenomic interrogation of CD4+ Th cells that extends previous findings focusing on individual loci. In this review, we provide an overview of recent genome-wide insights into the transcriptional and epigenetic regulation of CD4+ T cell-mediated adaptive immunity and discuss the implications for disease as well as immunotherapies.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.91-91
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• 2017

Drought is the most serious abiotic stress limiting rice production. However, little progress has been made in the genetic analysis of drought tolerance, because it is a complex trait controlled by a number of genes and affected by various environmental factors. In here, we screened 218 rice genetic resources for drought tolerance at vegetative stage and selected 32 highly drought tolerant varieties in greenhouse. Under rain-fed conditions, Grain yield of Nagdong was decreased by 53.3% from 517 kg/10a to 241 kg/10a when compare to irrigation condition. By comparison, grain yield of Samgang was decreased by 23.6% from 550 kg/10a to 420 kg/10a. The variety Samgang exhibited strong drought tolerance and stable yield in rain-fed conditions and was selected for further study. To identify QTLs for drought tolerance, we examined visual drought tolerance (VDT) and relative water content (RWC) using a doubled haploid (DH) population consisted of 101 lines derived from a cross between Samgang (a drought tolerance variety) and Nagdong (a drought sensitive variety). Three QTLs for VDT were located on chromosomes 2, 6, and 11, respectively, and explained 41.8% of the total phenotypic variance. qVDT2, flanked by markers RM324 and S2016, explained 8.8% of the phenotypic variance with LOD score of 3.3 and an additive effect of -0.6. qVDT6 was flanked by S6022 and S6023 and explained 12.7% of the phenotypic variance with LOD score of 5.0 and an additive effect of -0.7. qVDT11, flanked by markers RM26765 and RM287, explained 19.9% of the phenotypic variance with LOD score of 7.1 and an additive effect of -1.0. qRWC11 was the only QTL for RWC to be identified; it was in the same locus as qVDT11. qRWC11 explained 19.6% of the phenotypic variance, with a LOD score of 4.0 and an additive effect of 9.7. To determine QTL effects on drought tolerance in rain-fed paddy conditions, seven DH lines were selected according to the number of QTLs they contained. Of the drought tolerance associated QTLs, qVDT2 and qVDT6 did not affect tiller formation, but qVDT11increased tiller number. Tiller formation was most stable when qVDT2 and qVDT11 were combined. DH lines with both of these drought tolerance associated QTLs exhibited the most stable tiller formation. These results suggest that qVDT11 is important for drought tolerance and stable tiller formation under drought stress condition in field.

• Journal of Life Science
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• v.29 no.7
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• pp.800-808
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• 2019

Charcot-Marie-Tooth disease (CMT) is a group of rare peripheral neuropathies characterized by progressive muscle weakness and atrophy and areflexia in the upper and lower extremities. The most common subtype of CMT is CMT1A, which is caused by a tandem duplication of the PMP22 gene in the 17p12 region. Patients with CMT1A show a loose genotype-phenotype correlation, which suggests the existence of secondary genetic or association factors. Recently, polymorphisms of rs71428439 (n.83A>G) and rs2292832 (n.86T>C) in the MIR149 have been reported to be associated with late onset and mild phenotypic CMT1A severity. The aim of this study was to examine the intrafamilial heterogeneities of clinical phenotypes according to the genotypes of these two SNPs in MIR149. For this study, we selected 6 large CMT1A families who showed a wide range of phenotypic variation. This study suggested that both SNPs were related to the onset age and severity in the dominant model. In particular, the AG+GG (n.83A>G) and TC+CC genotypes (n.86T>C) were associated to late onset and mild symptoms. Motor nerve conduction velocity (MNCV) was not related to the MIR149 genotypes. These results were consistent with the previous studies. Therefore, we suggest that the rs71428439 and rs2292832 variants in MIR149 may serve as genetic modifiers of CMT1A intrafamilial phenotypic heterogeneity, as they have a role in the unrelated patients. This is the first study to show an association using large families with variable clinical CMT1A phenotypes. The results will be helpful in the molecular diagnosis and treatment of patients with CMT1A.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1205-1215
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• 2012

This study was conducted to establish genetic criteria for phenotypic characteristics of Hanwoo cattle based on allele frequencies and genetic variance analysis using microsatellite markers. Analysis of the genetic diversity among 399 Hanwoo cattle classified according to nose pigmentation and coat color was carried out using 22 microsatellite markers. The results revealed that the INRA035 locus was associated with the highest $F_{is}$ (0.536). Given that the $F_{is}$ value for the Hanwoo INRA035 population ranged from 0.533 (white) to 1.000 (white spotted), this finding was consistent with the loci being fixed in Hanwoo cattle. Expected heterozygosities of the Hanwoo groups classified by coat colors and degree of nose pigmentation ranged from $0.689{\pm}0.023$ (Holstein) to $0.743{\pm}0.021$ (nose pigmentation level of d). Normal Hanwoo and animals with a mixed white coat showed the closest relationship because the lowest $D_A$ value was observed between these groups. However, a pair-wise differentiation test of $F_{st}$ showed no significant difference among the Hanwoo groups classified by coat color and degree of nose pigmentation (p<0.01). Moreover, results of the neighbor-joining tree based on a $D_A$ genetic distance matrix within 399 Hanwoo individuals and principal component analyses confirmed that different groups of cattle with mixed coat color and nose pigmentation formed other specific groups representing Hanwoo genetic and phenotypic characteristics. The results of this study support a relaxation of policies regulating bull selection or animal registration in an effort to minimize financial loss, and could provide basic information that can be used for establishing criteria to classify Hanwoo phenotypes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.39-45
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• 1964

The phenotypic and genotypic correlations and heritabitities were calculated on 10 characters measured, using 10 native and 10 of introduced soybean varieties planted on 7 times with 15 days interval from April 15th. The genotypic correlations associated with grain yield were partitioned in to direct and indirect effects through the path coefficient analysis. The results are summarized as follows; 1. Generally high associations between characters were found, with high genotypic correlations than phenotypic, due to, probably, the fact that non segregating fixed varieties were used, and that the environmental effects were not elliminated appropreately here. Neverthless, the relative degree of association could be estimated. 2. The degree of associations of characters were different according the planting time, requiring the considerations on the specific characteristics depending on the specific planting time. 3. The introduced varieties were different with native ones in many respects, especially on the associations with stem length, stem diameter and seed weight. Here, the degree and the directions of the associations in the introduced ones were some peculier. 4. The less significant differences of characters between native varieties caused the heritability of native lower than that of introduced except the heritability of days from blooming to mature and seed weight. 5. The genetic associations of characters, measured, with grain yield were partitioned in to direct and indirect effects, calculating path coefficients. The days to bloom, stem length and stem diameter were most significantly affected the grain yield in the 5th planting of native ones.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.51-56
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• 2008

Azuki bean has never been commercially grown in Thailand, due in part to a lack of suitable varieties. A core collection of 114 azuki bean accessions, originally from different parts of China(northern, central, southern) representing the germplasm of Chinese land races, were evaluated in the experimental field of the Institute of Vegetable Crops, Jiangsu Academy of Agricultural Sciences, China from June to October 2004. The same experiment was repeated at Kamphaeng Saen campus of Kasetsart University, Thailand from February to May 2005. Yield, yield components, and agronomic traits were recorded in all accessions in order to identify certain genotypes for further investigation. The statistical parameters that were used as indicators of phenotypic variation were mean, coefficient of variability(CV), correlation coefficient(r), range, mean difference, and phenotypic clustering of the accessions. The results indicated that the azuki bean varieties planted in Kamphaeng Saen were shorter, earlier in growing duration, and lower in plant height, seed yield per plant, 100-seed weight, and pods per plant as compared to when they were grown in China. This discrepancy was caused largely by the combined effect of temperature, rainfall, and day length. The traits that were rather stable in both locations were branches per plant and seeds per pod. Azuki bean varieties from northern China showed higher response to the changing environments compared with those from central and southern China. Some agronomic traits showed high correlation coefficient between the environments in Thailand and China. The CV of agronomic traits in both locations were ranked in descending order as follows: seed yield per plant, pods per plant, branches per plant, plant height, 100-seed weight, seeds per pod, and growing duration. The CV of seeds per pod and branches per plant were almost the same in both locations. Yield per plant in China correlated well(r=0.75) with pods per plant, but not with the other traits. Based on their response to both environments, the azuki bean accessions can be broadly divided into four groups, viz. northern 1, northern 2, central, and southern. This implied that there was more diversity, but probably less stability among the accessions originating from northern China.

• Korean Journal of Plant Resources
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• v.29 no.6
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• pp.679-689
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• 2016

Lettuce is an important annual leafy vegetable and bitterness is its potent flavor character. Lettuce germplasm differ their phenotypic characters and sesquiterpene lactones (SLs) contents which are important for consumer's acceptance. This study was carried out to evaluate the phenotypic characters and SLs contents in one hundred lettuce germplasm in Jeonju, Korea. Twenty-three agro-morphological (16 qualitative and 7 quantitative) traits and two SLs (lactucin and lactucopicrin) contents were studied in these germplasm. Germplasm exhibited the variation in qualitative and quantitative characters. Average plant weight was 423.9 g with a range from 116.0 to 905.0 g. Lactucin content was varied from 19.7 (IT 294226) to $194.4{\mu}g/g$ (IT 294298) with an average concentration of $84.7{\mu}g/g$. Lactucopicrin ranged from 82.5 (IT 300134) to $2228.6{\mu}g/g$ (IT 294210) with an average concentration of $586.3{\mu}g/g$. Total SLs content was ranged from 120.1 (IT 300134) to 2286.6 (IT 294210)${\mu}g/g$ with the average concentration of $671.0{\mu}g/g$. Significant ($p{\leq}0.05$) differences were found between crisp head and butter head germplasm for lactucin, lactucopicrin and total SLs content. Crisp head germplasm revealed the highest average lactucin ($112.9{\mu}g/g$), lactucopicrin ($734.8{\mu}g/g$) and total SLs content ($847.7{\mu}g/g$). Crisp head and leafy type germplasm exhibited more total SLs content (847.7 and $744.7{\mu}g/g$, respectively) than cos ($524.9{\mu}g/g$) and butter head type ($519.4{\mu}g/g$). Principal component analyses of the quantitative traits indicated that the first principal component axis accounted more than 91% of the total variation. This study revealed the ample genetic variation in the agro-morphological traits and SLs contents to support the selection for improved lettuce varieties.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.192-197
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• 2013

This study examined the phenotypic and molecular characteristics of the $2^{nd}$ clone ($T_0V_2$) plants of LeLs-antisense gene-transgenic chrysanthemum line (LeLs80) that exhibited non-branching, proving the relevance of these characteristics as a factor for use in environmental risk assessment. Results of the Southern blot analysis showed that three copies of the LeLs-antisense gene were introduced into the transgenic line, and northern analysis showed that the transcripted gene was normally expressed in the transgenic line. A flanking T-DNA sequencing method was used to determine that sequences of 184 and 464 bps flanked the LeLs-antisense gene in the transgenic line. These sequences, respectively, matched the 35S promoter for expression of the npt II gene and the NOS terminator for expression of the LeLs-antisense gene within the pCAMBIA 2300 vector.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.366-374
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• 2014

The study was conducted to investigate the possibility that epigenetic DNA methylation causes tree phenotypic variation in autotetraploids through evaluating the phenotypic variation and DNA methylation in autotetraploids occurred spontaneously from diploid trifoliate orange. Chromosome analysis confirmed that fourteen trifoliate orange trees of selected by flow cytometry were tetraploids (2n = 4X = 36) without any aneuploids. Chromomycin A3 staining determined that these trees were all autotetraploid with doubled chromosome set. Tree phenotypes, such as tree height and width, branching number, length, and angle, internode length, and leaf characteristics, varied in the autotetraploids. Chlorophyll indices were diverse in the autotetraploids, but photosynthetic rates were not significantly different. In addition, a wide range of variation was observed in stomatal density and guard cell length. Analysis of global cytosine DNA methylation showed that there was a variation of the methylation level in autotetraploids. More than half of 14 autotetraploids had at least 2 times higher methylation level than diploid trifoliate orange. The results indicate that tree phenotypic variation in autotetraploids might be related to global DNA methylation for reducing gene redundancy.