• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.18-26
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• 2013

Genetically modified (GM) rice Agb0101, which expresses the insecticidal toxin modified cry1Ac (mcry1Ac1) gene, was developed by the Rural Development Administration in Korea. To monitor the probable release of Agb0101 in the future, it is necessary to develop a reliable detection method. Here, we developed the PCR detection method for monitoring and tracing of GM rice. The primer pair (RBEgh-1/-2) from a starch branching enzyme (RBE4) gene was designed as an endogenous reference, giving rise to an expected PCR amplicon of 101 bp. For the qualitative PCR detection, construct- and event-specific primers were designed on the basis of integration sequence of T-DNA. Event-specific PCRs amplified specifically 5'- or 3'-junction region spanning the native genome DNA and the integrated gene construct, while none of amplified product was shown on crops, rice varieties, and other insect-resistant transgenic rice lines. The event-specific real-time PCR method was performed using TaqMan probe and plasmid pRBECrR containing both rice endogenous gene RBE4 sequence and 5'-junction sequence as the reference molecule. The absolute limit of quantification (LOQ) of real-time PCR was established with around 10 copies for one plasmid molecule pRBECrR. Thereafter, the different amounts of transgenic rice (1, 3, 5, and 10%, respectively) were quantified by using the established real-time PCR method, with a range below 19.55% of the accuracy expressed as bias, 0.06-0.40 of standard deviation (SD) and 3.80-7.01% of relative standard deviations (RSD), respectively. These results indicate that the qualitative and quantitative PCR methods could be used effectively to detect the event Agb0101 in monitoring and traceability.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.193-196
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• 2001

IL-18. formerly known as IGIF(interferon -gamma inducing factor), is structurally IL-l related but functionally IL-12 related pro-inflammatory cytokine. The human IL -18(hIL-lS), like IL-$1{\beta}$, is synthesized as a biologically inactive precursor of 24kDa lacking a signal peptide, and then cleaved into an active mature form by cystein protease IL-$1{\beta}$ converting enzyme (ICE: caspase- 1), We tested if the mature hIL -18 can be expressed and secreted into culture medium by transforming the forming gene construct consisting of a mature hIL-18 gene fused to signal peptide of rice amylase lA. Secondly, we were tested if the pro- IL-18 could be processed into a biologically active form by caspase-l like protease in plant. Cell suspension culture was established from the leaf-derived calli of transgenic tobacco plant. Southern and Northern blot analysis indicated the expression of both pro-hIL-18 and mature hIL-18 plant cells. Western blot analysis introduced the protein products of pro- hIL -18 and mhIL -18 were observed in transigenic cell lines. In addition, the molecular size of recombinant pro-hILl-18 and mhIL-18 were estimated to be 24kDa and 18kDa, respectively. ELISA revealed that the amount of pro- hIL -18 was 1.3ug per gram of fresh weight calli. Moreover, the presence of mhIL-18 was detected in the culture medium and it appeared to be 25ug/L.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.37-42
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• 2013

Rice is one of the most important cereal crops as a model plant for functional genomics of monocotyledons and usually transformed using Agrobacterium tumefaciens. However, the transformation's process using previous method is still time consuming and uneconomical, low efficiency. In this study, we established a new method by modifying the general Agrobacterium protocol especially in the infection and co-cultivation, Agrobacterium elimination, infected calli's selection steps using liquid media. We directly inoculated Agrobacterium containing a ZjLsL gene under the control of constitutive promoter into the 1- to 3-week-old rice calli derived from mature seeds. After 3 days of co-cultivation, the infected calli were transferred onto liquid media of Agrobacterium elimination and calli's selection for 3 days. The calli were transferred to calli's growth solid media for 14 days and then the calli transferred to shoot induction and root induction media. Putative transformants were initially selected on the medium containing phosphinothricin, and the PAT protein verified by PAT strip test. This method in this study would lead to reduction of substantial labor and time to generate transgenic plants.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.4
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• pp.138-147
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• 2024

Agrobacterium-mediated transformation (AMT) is a method that allows for the stable integration of DNA fragments into the plant genome. Transgenic plants generated through AMT typically exhibit a lower copy number of the transgene compared to those induced by particle bombardment. Furthermore, AMT offers a straightforward and efficient approach for generating transgenic plants. While the transformation efficiency of wheat is comparatively lower than that of other monocot plants such as Rice (Oryza sativa L.) and Maize (Zea mays L.), the cultivars 'Bobwhites' and 'Fielder' are commonly employed for wheat transformation. To date, there have been no reported instances of successful development of transgenic plants using Korean wheat varieties through AMT. This study aims to assess the transformation efficiency of 43 Korean wheat cultivars using the GUS assay, with the goal of identifying suitable Korean wheat cultivars for AMT. The pCAMBIA1301 vector, carrying the β-glucuronidase (GUS) gene, was incorporated into Agrobacterium strain EH105. Following the inoculation of Agrobacterium into immature embryos, GUS assays were conducted 'Saeol', 'Jopum', and 'Jonong' showed 100% (the number of embryos showing GUS spots/the number of embryos used for AMT) among 43 cultivars. In addition, cultivars with more than 70% were 'Saekeumgang', 'Jojung', 'Tapdong', 'Anbaek', 'Dabun', 'Sugang', 'Keumgang', 'Jeokjung', 'Seodun', 'Joeun', 'Dajung', and 'Baekjung'. It seems that the 15 cultivars above showed the possibility of using AMT. On the other hand, 'Yeonbaek', 'Goso', 'Baekgang', and 'Johan' showed less than 20% and GUS spots were not observed in 'Gru', 'Gobun', 'Milseong', and 'Shinmichal-1'. This study explores transient GUS expression in Korean wheat cultivars seven days after AMT. The observed initial high efficiency of transient transformation suggests the potential for subsequent stable transformation efficiency. Korean wheat cultivars demonstrating elevated transient transformation efficiency could serve as promising candidates for the development of stable transgenic wheat.

• 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.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.98-98
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• 2017

Leaf senescence is the process of aging in plants. Chlorophyll degradation during leaf senescence has the important role translocating nutrients from leaves to storage organs. The functional stay-green with slow leaf yellowing and photosynthesis activity maintenance has been considered one of strategy for increasing crop productivity. Here, we have identified two QTLs on chromosome 9 and 10 for leaf senescence with chlorophyll content of RIL population derived from a cross between Hanareum 2, early leaf senescence Indica-type variety, and Unkwang, delayed leaf senescence Japonica variety. Among these QTLs, we chose qPLS1 QTL on chromosome 9 for further study. qPLS1 was found to explain 14.4% of the total phenotypic variation with 11.2 of LOD score. Through fine-mapping approach, qPLS1 QTL locus was narrowed down to about 25kb in the marker interval between In/del-4-7-9 and In/del-5-9-4. There are 3 genes existed within 25kb of qPLS1 locus: LOC_Os09g36200, LOC_Os09g36210, and LOC_Os09g36220. Among these genes, transcript level of LOC_Os09g36200 was increased during the leaf senescence stage and the expression level of LOC_Os09g36200 in Indica was higher than in Japonica. Finally, we chose LOC_Os09g36200 as candidate gene and renamed it as OsPLS1-In and OsPLS1-Jp from Indica- and Japonica-type rice, respectively. OsPLS1-In and OsPLS1-Jp overexpressing transgenic plants showed both early leaf senescence phenotype. These results indicate that OsPLS1 functions in chlorophyll degradation and the difference of expression level of OsPLS1 cause the difference of leaf senescence between Indica and Japonica in rice.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.108-116
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• 2003

A series of new quinclorac family, herbicidal 3-phenyl-5-(3,7-dichloro-8-quinolinyl)-1,2,4-oxadiazole derivatives as substrate were synthesized and their growth inhibition activity $(pI_{50})$ against root and shoot of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) were determined. And then comparative molecular field analysis (CoMFA) and molecular holographic quantitative structure- activity relationship (HQSAR) were compared in terms of their potential for predictiability. The statistical results were suggested that HQSAR based model had better predictability than CoMFA model. The selective factors to remove barnyard grass take electron withdrawing groups which can be created positive charge and steric bulky on the phenyl ring. Results revealed that the unknown 2,6-dichloro-substituent, U5 and 2,4,6-trichloro-substituent, U6(${\Delta}pI_{50}$=CoMFA: 1.18 & HQSAR: 1.82) were predicted as compound with higher activity and selectivity.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.406-414
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• 2018

This study was conducted to develop environmental risk assessments and biosafety guides for insect-resistant genetically modified rice in an LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-T), rice resistant to Cnaphalocrocis medinalis, and non-GM rice (Dongjin-byeo and Ilmi-byeo) were investigated. The Bt-T plants were, therefore, evaluated under field conditions to detect possible impacts on above ground insects and spiders. In 2016 and 2017, the study compared transgenic rice and two non-GM reference rice, namely Dongjin-byeo and Ilmi-byeo, at Gunwi. A total of 9,552 individuals from 51 families and 11 orders were collected from the LMO isolation field. From the three types of rice fields, a total of 3,042; 3,212; and 3,297 individuals from the Bt-T, Dongjin-byeo, and Ilmi-byeo were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies, and other insects on the Bt-T compared to non-GM rice. The data on insect species population densities were subjected to principal component analysis (PCA) without distinguishing between the three varieties, namely GM, non-GM, and reference cultivar, in all cultivation years. However, the PCA clearly separated the samples based on the cultivation years. These results suggest that insect species diversities and population densities during plant cultivation are determined by environmental factors (growing condition and seasons) rather than by genetic factors.

• Molecules and Cells
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• v.28 no.2
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• pp.105-109
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• 2009

We reported previously that overexpression of a salicylic acid (SA) methyltransferase1 gene from rice (OsBSMT1) or a SA glucosyltransferase1 gene from Arabidopsis thaliana (AtSAGT1) leads to increased susceptibility to Pseudomonas syringae due to reduced SA levels. To further examine their roles in the defense responses, we assayed the transcript levels of AtBSMT1 or AtSAGT1 in plants with altered levels of SA and/or other defense components. These data showed that AtSAGT1 expression is regulated partially by SA, or nonexpressor of pathogenesis related protein1, whereas AtBSMT1 expression was induced in SA-deficient mutant plants. In addition, we produced the transgenic Arabidopsis plants with RNAi-mediated inhibition of AtSAGT1 and isolated a null mutant of AtBSMT1, and then analyzed their phenotypes. A T-DNA insertion mutation in the AtBSMT1 resulted in reduced methyl salicylate (MeSA) levels upon P. syringae infection. However, accumulation of SA and glucosyl SA was similar in both the atbsmt1 and wild-type plants, indicating the presence of another SA methyltransferase or an alternative pathway for MeSA production. The AtSAGT1-RNAi line exhibited no altered phenotypes upon pathogen infection, compared to wild-type plants, suggesting that (an)other SA glucosyltransferase(s) in Arabidopsis plants may be important for the pathogenesis of P. syringae.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.289-296
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• 2001

The main objective of this topic is to establish strategies and to plan biotechnology researches which are related to the agricultural improvements especially focusing on the crop breeding in Korea. From 1960's to 1980's government policy had been emphasized to develope high yielding cultivars for the self sufficient supply of the staple food crops. As a result, considerable increase of rice production has been made with accumulating technology and man's powers. Recently genetically modified crops harboring useful characteristics have been developed using biotechnology and released in the developed countries. National research institutes and private companies have been developed biotechnology researches to establish competitive capabilities, however they have not been successfully used in commercialization. Therefore it is necessary to promote the practical. application by connecting molecular technology with conventional breeding. Proposed research projects are; (1) basic researches including plant genome studies, (2) developing new cultivars through gene transformation, (3) screening and producing antioxidants, secondary metabolite substances and edible vaccines. To set a government policy, both domestic and international research trends were reviewed and possibility of success based on the economic view point were discussed. The intellectual property and preservation of environment play a key role to decide the research priority. It is also necessary for us to make one step system for the distribution of research resources such as microorganisms, genes cloned, plant seeds and research informations for promoting research activities.