• KSBB Journal
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• v.28 no.4
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• pp.260-268
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• 2013

Transgenic plant cell cultures are an attractive expression system for the production of industrial and pharmaceutical proteins because of their advantages in safety and low production cost. Human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) was produced and secreted when sugar was depleted in culture medium by transgenic rice cell lines (Oryza sativa L.) using RAmy3D promoter. Due to the production of the target protein by sugar depletion, concomitant occurrence of cell death is inevitable. For that reason, inhibition of cell death for enhancing productivity was necessary for the production period without energy sources. Supplementation of 0.1 mM sodium nitroprusside improved cell viability by 1.4-fold and maximum hCTLA4Ig production by 1.3-fold compared to those of control. Addition of 1 and 10 mM glutathione, N-acetylcysteine (NAC), and nicotinamide inhibited apoptotic-like programmed cell death by decreasing the activity of reactive oxygen species. Production hCTLA4Ig was enhanced 1.4-, 1.25-, and 1.15-fold with 10 mM NAC, 1 mM NAC, and 1 mM glutathione, respectively. In addition, it was found that the supplementation of NAC enhanced the cell viability.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.1-10
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• 2010

Five mutants were investigated at the molecular level to determine the factors responsible for mutated endosperm types. They were classified as high (HA) or low amylose (LA) phenotypes based on the amylose content in endosperm. The five were previously produced from Ilpum and Shindongjin cultivar treated with N-methyl-N-nitrosourea and gamma-ray irradiation, respectively. Analysis of the genomic structure and expression of Granule-bounded Starch Synthase I (GBSSI) genes revealed that mutants generally showed a higher incidence of nucleotide transition than transversion, and the $A:T{\rightarrow}G:C$ transition was particularly prevalent. The rates of nucleotide substitution in HA mutants were generally higher than those in the LA mutants, leading to higher substitutions of amino acid in the HA mutants. Neither nucleotide substitutions interfering with intron splicing or causing early termination of protein translation were found, nor any large-sized deletions or additions were found in all the mutants. In principle, amylose content can be regulated by three factors: internal alterations of GBSSI protein, the strength of gene expression, and other unknown external factors. Our results indicate that the endosperm mutants from Shindongjin arose from internal alterations of GBSSI proteins, which may be the result of amino acid substitutions. On the other hand, the Ilpum mutants might be principally caused by the alteration of gene expression level. Analysis of another three glutinous cultivars revealed that the major factor leading to glutinous phenotypes is the 23-bp duplicative motif (5'-ACGGGTTCCAGGGCCTCAAGCCC-3') commonly found in exon 2, which results in the premature termination of protein translation leading to the production of a non-functional GBSSI enzyme.

• Journal of Plant Biotechnology
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• v.35 no.3
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• pp.177-183
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• 2008

Ac/Ds mutant lines of this study were transgenic rice plants, each of which harbored the maize transposable element Ds together with a GUS coding sequence under the control of a promoterless(Ds-GUS). We selected the mutants that were GUS expressed lines, because the GUS positive lines will be useful for identifying gene function in rice. One of these mutants was identified knock-out at Oszinc626(NP_001049991) gene, encoding a RING-H2 zinc-finger protein, by Ds insertion. In this mutant, while primary root development is normal, secondary root development from lateral root was very poor and seed development was incomplete compare with normal plant. RING zinc-finger proteins play important roles in the regulation of development in a variety of organisms. In the plant kingdom, a few genes encoding RING zinc-finger proteins have been documented with visible effects on plant growth and development. The consensus of the RING-H2(C3-H2-C3 type) domain for this group of protein is $Cys-X_2-Cys-X_{28}-Cys-X-His-X_2-His-X_2-Cys-X_{14}-Cys-X_2-Cys$. Oszinc626 encodes a predicted protein product of 445 amino acids residues with a molecular mass of 49 kDa, with a RING-zinc-finger motif located at the extreme end of the C-terminus. RT-PCR analysis indicated that the expression of Oszinc626 gene was induced by IAA, cold, dehydration, high-salinity and abscisic acid, but not by 2,4-D, and the transcription of Oszinc626 gene accumulated primarily in rice immature seeds, root meristem and shoots. The gene accumulation patterns were corresponded with GUS expression.

• 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.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.250-261
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• 2010

The expression of vaccine antigens in transgenic plants has the potential to provide a convenient, stable, safe approach for oral vaccination alternative to traditional parenteral vaccines. Over the past two decades, many different vaccine antigens expressed via the plant nuclear genome have elicited appropriate immunoglobulin responses and have conferred protection upon oral delivery. Up to date, efforts to produce antigen proteins in plants have focused on potato, tobacco, tomato, banana, and seed (maize, rice, soybean, etc). The choice of promoters affects transgene transcription, resulting in changes not only in concentration, but also in the stage tissue and cell specificity of its expression. Inclusion of mucosal adjuvants during immunization with the vaccine antigen has been an important step towards the success of plant-derived vaccines. In animal and Phase I clinical trials several plant-derived vaccine antigens have been found to be safe and induce sufficiently high immune response. Future areas of research should further characterize the induction of the mucosal immune response and appropriate dosage for delivery system of animal and human vaccines. This article reviews the current status of development in the area of the use of plant for the development of oral vaccines.

• Microbiology and Biotechnology Letters
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• v.5 no.4
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• pp.167-169
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• 1977

Cellulosic single cell proteins produced from rice straw by three strains of cellulolytic bacteria were analysed for their composition and for their amino acid patterns. It was showed that they contains 52.2∼70.3％ of crude Protein, 11.6∼13.9％ of crude fat and 11.5∼18.1％ of ash. The sulphur containing amino acids and threonine were analysed to be the limiting amino acid in the cellulosic SCP. The protein scores were calculated as 80.0 for Cellulomonas flavigena KIST 321, 78.00 for Cellulomonas fimi and 61.8 for Cellulomonas aurogena KIST 11. The nutritional value of the cellulosic SCP is discussed from the results.

• Korean Journal of Pharmacognosy
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• v.17 no.2
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• pp.134-138
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• 1986

Based on a tracer study, starch phosphorylase was implicated as an agent in the starch synthesis in sweet potato roots. The enzyme was purified from the tissue as a cluster of isozymes with an average mw of 205K (fresh roots) or 159K (roots stored for 3 mon.). On SDS polyacrylamide gel electrophoresis, one large subunit of 98K mw and several small ones of 47${\sim}57K mw were observed. From the mw data and the results of peptide mapping and immunoelectrophoretic blotting using mono- and polyclonal antibodies, it was deduced that a large part of the large subunit was cleaved at the middle part of the peptide chain to give rise to the small subunits, and on storage, the enzyme molecules were further modified by proteolysis. During the course of phosphorylase purification, a proteinaceous inhibitor of the enzyme was isolated. It had a mw of 250K and was composed of 5 identical subunits of 51K mw. In the direction of starch synthesis, the inhibitor showed a noncompetitive kinetics with a Ki of $1.3{\times}10^{-6}\;M$. By immunohistochemical methods, both the enzyme and the inhibitor were located on the cell wall and amyloplast. Crossreacting materials of the inhibitor were present in spinach leaf, potato tuber and rice grain. These findings indicate the wide occurrence of the inhibitor and also imply its possible participation in regulating starch phosphorylase activity in vivo.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.217-222
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• 2021

Barnyard millet is a short-lived tropical, short-term C4 plant and has superior vitality in humid conditions owing to its freshwater habitat. It shows strong adaptability to soils with poor drainage and low fertility, and efficiently competes with rice in paddy fields. Barnyard millet grain is used as feed in the Indian region and is a great source of dietary fiber, proteins, fats, vitamins, and some essential amino acids. Considering its high nutritional value and its potential as a food resource and fodder crop, various countries are showing interest in cultivating barnyard millet. However, in Korea, farm households have not yet recognized the benefits of cultivating barnyard millet, and research regarding this is scarce. In this review, the features of forage barnyard millet and its related research trends are discussed, with the aim of improving interest in this crop and promoting its cultivation.

• Journal of Plant Biotechnology
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• v.50
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• pp.232-238
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• 2023

Histone deacetylases (HDACs) play a pivotal role in epigenetic regulation, affecting the structure of chromatin and gene expression across different stages of plant development and in response to environmental stresses. Although the role of HDACs in Arabidopsis and rice has been focused on in extensive research, the role of the HDAC gene family in various medicinal plants remains unclear. In the genome of the balloon flower (Platycodon grandiflorus), we identified 10 putative P. grandiflorus HDAC (PlgHDAC) proteins, which were classified into the three families (RPD3/HDA1, SIR2, and HD2 HDAC families) based on their domain compositions. These HDACs were predicted to be localized in various cellular compartments, indicating that they have diverse functions. In addition, the tissue-specific expression profiles of PlgHDACs differed across different plant tissues, indicating that they are involved in various developmental processes. Furthermore, the expression levels of all PlgHDACs were upregulated in leaves after waterlogging treatment, implying their potential role in coping with waterlogging-induced stress. Overall, our findings provide a comprehensive foundation for further research into the epigenetic regulation of PlgHDACs, and particularly, on their functions in response to environmental stresses such as waterlogging. Understanding the roles of these HDACs in the development and stress responses of balloon flower could have significant implications for improving crop yield and the quality of this important medicinal plant.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.517-524
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• 1993

To characterize glutelins, the most abundant storage protein in rice, 13 complete coding sequences of glutelin genes from the database were analyzed. According to the phylogenic analysis, these genes could be classified into 5 groups, Group I to V. The degrees of homology were calculated to be in the range of 90 to 60%, but the patterns of hydrophobicity were similar in all the groups. Also, each group was found to have similar amino acid composition with variations in lysine content from 2.5 to 3.6% due to the point mutation of arginine to lysine. The isoelectric points of mature proteins and their basic chains of all the groups showed the value of about 9.0 and 10.0, respectively, while the isoelectric points of acidic chains in these groups showed the distinct value of 6.6, 6.7, 7.2, 8.4 and 7.9. The plot of the fraction of G+C at synonimous site in codons (GC3s) against effective codon numbers suggest no major difference in translational efficiency in the expression of glutelin multigenes.