• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.348-349
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• 2006

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.413-425
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• 2018

A previous work developed and identified a new omega-5 gliadin deficient wheat line named O-free by crossing Keumkang and Olgeuru, which is nutritionally quite meaningful in that omega-5 gliadin is one of the known wheat allergens. To verify the characteristics of the O-free, we performed RNA sequencing (RNAseq) analysis of the O-free and the two parent lines (Keumkang and Olgeuru). The results of the similarity analysis with the ESTs for gliadins and glutenins showed that the O-free ESTs had no similarity with the omega-5 gliadin sequences but had similarity to other gliadins and glutenins. Furthermore, mapping results between the raw RNAseq data from the O-free and the omega-5 gliadin sequence showed a clear deletion of the N-terminal sequences which are an important signature of omega-5 gliadin. We also designed specific PCR primers that could identify omega-5 gliadin in the genomic DNA. The results showed that no omega-5 gliadin fragments were detected in the O-free. According to these results, we confirmed that the deficiency of omega-5 gliadin in the O-free is not caused by post-transcriptional or post-translational regulations such as epigenetic phenomena but by a simple deletion in the chromosome. Furthermore, we showed that the low-molecular weight glutenin subunit (LMW-GS) gene in the O-free had a single nucleotide polymorphism (SNP) causing a premature stop codon, resulting in a truncated polypeptide. We expect that the O-free line may serve as an excellent source of wheat that could prevail in the hypo-allergen wheat market, which has recently gained interest world-wide.

• Journal of Life Science
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• v.26 no.10
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• pp.1121-1129
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• 2016

High-molecular-weight glutenin subunits (HMW-GSs) are extremely important determinants of the functional properties of wheat dough. Transgenic rice plants containing a wheat TaGlu-Ax1 gene encoding a HMG-GS were produced from the Korean wheat cultivar ‘Jokyeong’ and used to enhance the bread-making quality of rice dough using the Agrobacterium-mediated co-transformation method. Two expression cassettes with separate DNA fragments containing only TaGlu-Ax1 and hygromycin phosphotransferase II (HPTII) resistance genes were introduced separately into the Agrobacterium tumefaciens EHA105 strain for co-infection. Rice calli were infected with each EHA105 strain harboring TaGlu-Ax1 or HPTII at a 3:1 ratio of TaGlu-Ax1 and HPTII. Among 210 hygromycin-resistant T₀ plants, 20 transgenic lines harboring both the TaGlu-Ax1 and HPTII genes in the rice genome were obtained. The integration of the TaGlu-Ax1 gene into the rice genome was reconfirmed by Southern blot analysis. The transcripts and proteins of the wheat TaGlu-Ax1 were stably expressed in rice T₁ seeds. Finally, the marker-free plants harboring only the TaGlu-Ax1 gene were successfully screened in the T₁ generation. There were no morphological differences between the wild-type and marker-free transgenic plants. The quality of only one HMW-GS (TaGlu-Ax1) was unsuitable for bread making using transgenic rice dough. Greater numbers and combinations of HMW and LMW-GSs and gliadins of wheat are required to further improve the processing qualities of rice dough. TaGlu-Ax1 marker-free transgenic plants could provide good materials to make transgenic rice with improved bread-making qualities.

• Journal of Life Science
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• v.23 no.11
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• pp.1317-1324
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• 2013

High-molecular weight glutenin subunits (HMW-GS) have been shown to play a crucial role in determining the processing properties of the wheat grain. We have produced marker-free transgenic rice plants containing a wheat Glu-1Bx7 gene encoding the HMG-GS from the Korean wheat cultivar 'Jokyeong' using the Agrobacterium-mediated co-transformation method. The Glu-1Bx7-own promoter was inserted into a binary vector for seed-specific expression of the Glu-1Bx7 gene. Two expression cassettes comprised of separate DNA fragments containing only Glu-1Bx7 and hygromycin phosphotransferase II (HPTII) resistance genes were introduced separately to the Agrobacterium tumefaciens EHA105 strain for co-infection. Each EHA105 strain harboring Glu-1Bx7 or HPTII was infected to rice calli at a 3:1 ratio of Glu-1Bx7 and HPTII, respectively. Then, among 216 hygromycin-resistant $T_0$ plants, we obtained 24 transgenic lines with both Glu-1Bx7 and HPTII genes inserted into the rice genome. We reconfirmed integration of the Glu-1Bx7 gene into the rice genome by Southern blot analysis. Transcripts and proteins of the wheat Glu-1Bx7 were stably expressed in the rice $T_1$ seeds. Finally, the marker-free plants harboring only the Glu-1Bx7 gene were successfully screened at the $T_1$ generation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.249-249
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• 2017

• Journal of Life Science
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• v.22 no.9
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• pp.1152-1158
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• 2012

Development of transgenic plant increasing crop yield or disease resistance is good way to solve the world food shortage. However, the persistence of marker genes in crops leads to serious public concerns about the safety of transgenic crops. In the present paper, we developed marker-free transgenic rice inserted high molecular-weight glutenin subunit (HMW-GS) gene ($D{\times}5$) from the Korean wheat cultivar 'Jokyeong' using Agrobacterium-mediated co-transformation method. Two expression cassettes comprised of separate DNA fragments containing only the $D{\times}5$ and hygromycin resistance (HPTII) genes were introduced separately into Agrobacterium tumefaciens EHA105 strain for co-infection. Each EHA105 strain harboring $D{\times}5$ or HPTII was infected into rice calli at a 3: 1 ratio of EHA105 with $D{\times}5$ gene and EHA105 with HPTII gene expressing cassette. Then, among 66 hygromycin-resistant transformants, we obtained two transgenic lines inserted with both the $D{\times}5$ and HPTII genes into the rice genome. We reconfirmed integration of the $D{\times}5$ and HPTII genes into the rice genome by Southern blot analysis. Wheat $D{\times}5$ transcripts in $T_1$ rice seeds were examined with semi-quantitative RT-PCR. Finally, the marker-free plants containing only the $D{\times}5$ gene were successfully screened at the $T_1$ generation. These results show that a co-infection system with two expression cassettes could be an efficient strategy to generate marker-free transgenic rice plants.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.547-554
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• 2010

Low-molecular-weight glutenin subunit (LMW-GS) in common wheat (Triticum aestivum L.) is important for quality processing of bread and noodles. The objectives of this study were to clarify the composition of LMW-GSs and to identify their corresponding proteins. Using LMW-GS specific primers we cloned and characterized 43 LMW-GS genes in the wheat cultivar 'Jokyoung'. Some of these genes contain polypeptides different in size due to the presence of various deletions or insertions within repetitive and glutamine-rich domains. The comparison of deduced amino acid sequence of the LMW-GS genes in Jokyoung with that of 12 groups LMW-GSs of wheat cultivar Norin 61 showed that the deduced amino acid sequences were nearly the same to LMW-GS groups of 1, 2, 3/4, 5, 7, 10 and 11. All LMW-GS genes contain eight cysteine residues, which are conserved among all of the typical LMW-GS sequences. The relative positions of cysteine residues are also conserved, except those of the first and seventh. Based on phylogenetic analysis, the 43 sequences with the same N-terminal and C-terminal amino acid sequences were clustered in the same group. To identify the proteins containing the corresponding amino acid sequences, we determined the N-terminal amino acid sequence of 7 spots of LMW-GSs of Jokyoung separated by two-dimensional gel electrophoresis (2DE). Of them, Glu-B3 (LMW-m and LMW-s) and Glu-D3 (LMW-m) were detected in two and three spots, respectively and the others were not clear. Collectively, we classified diverse LMW-GSs and identified their corresponding protein products. These results will be helpful in breeding programs for improvement of wheat flour quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.2
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• pp.111-120
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• 2022

Improving flour quality is one of the major targets of wheat breeding programs. This study determined the optimum high-molecular-weight glutenin subunits (HMW-GS) to improve flour quality, and analyzed the correlation between agronomic and quality traits in Korea. A total of 180 wheat varieties, including 55 Korean and 125 foreign cultivars, carrying various Glu-1 alleles, were evaluated for their quality and agronomic traits. Results indicated that Glu-A1b, Glu-B1b, and Glu-D1f were the most prevailing alleles for each Glu-1 locus for Korean wheat cultivars. Korean wheat cultivars recorded shorter days to heading (DTH) and longer days to maturity (DTM) compared to foreign cultivars. In addition, an interaction effect was found between Glu-A1 and Glu-B1 alleles on several quality parameters. The combination of Glu-A1c and Glu-B1i showed a higher protein content, dry gluten content, and higher sodium dodecyl sulfate (SDS) sedimentation value than other Glu-A1×Glu-B1 combinations. Cultivars carrying Glu-A1a or Glu-A1b, Glu-B1i or Glu-B1al, and Glu-D1d for each Glu-1 locus exhibited a longer mixing time and stronger mixing tolerance. The DTM positively correlated with the protein content, gluten index and SDS sedimentation value. However, a negative correlation was observed between DTH and quality traits. Owing to the above results, this study suggests that an increase in the frequency of Glu-B1i or Glu-B1al, Glu-D1d coupled with a short DTH and long DTM could significantly improve wheat quality properties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.346-355
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• 2005

To investigate the application of biochemical markers' and small-sample methods using whole-wheat flours for screening in early generation in Korean wheat breeding system, 74 Korean wheats, including cultivars, local breeding lines and experimental lines, were analyzed. Seed storage protein and amylose contents of grains were evaluated. Biochemical makers, including granule bound starch synthase (GBSS), high molecular weigh glutenin subunits (HMW-GS) and friabilin were also evaluated by using one-dimensional sodium dodecyl sulfate-polyacryla-mide gel electrophoresis with a single kernel. The small­sample methods, including modified SDS-sedimentation test (MST), micro-alkaline water retention capacity (AWRC) and whole-wheat flour swelling volume (WSV) were also tested in this study. Protein content, MST and AWRC was $11.0 - 15.8\%$, 2.7 - 26.2 ml and $71.9 - 109.7\%$, respectively. Apparent and total amylose content and WSV was $20.6 - 25.0\%$, $26.1 - 32.4\%$ and 9.0 - 16.9 ml, respectively. There were highly significant correlations between MST and AWRC (r=0.592, P<0.001), but Korean wheats showed no significant difference in protein content, amylose content and small-sample methods. In the biochemical markers, Korean wheats contained all three GBSS encoded by Wx loci, except for Suwon 252. Korean wheats showed the high frequency ($58.1\%$) of 1Dx2.2 + 1Dy12 subunits of HMW-GS. Friabilin band was present in 46 lines ($62.2\%$) and absent in 28 lines ($37.8\%$). Friabilin-absence lines showed the higher MST (14.9 ml) and AWRC ($92.1\%$) value than friabilin-presence lines (8.5 ml and $82.4\%$, respectively).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.1-12
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• 2002

Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.