• Korean Journal of Plant Resources
• /
• v.17 no.2
• /
• pp.116-121
• /
• 2004

Panax ginseng discarded and lower than 4th grade is caused by red skin disease showing red color skin in ginseng. This kind of red skin ginseng is found a lot in Panax ginseng rather than Panax quinquefolium, and it is considered that red skin disease might be caused by gene. Therefore, this study was carried out to detect genes resistant to red skin disease using RT-PCR. RNA was extracted from three years old ginseng root of both red skin and normal portion in the same root. After RNA extraction, PCR amplification was performed from cDNA using many random primers. As a result, specific band for red skin was found. It is considered that the gene forming band has possibility to be related with red skin disease, and this gene should be decided if it's related with red skin disease. If that gene is related with red skin disease, it will be used for transformation to foster for resistance to red skin disease as well as for selection marker. Bowever, if it's not related with red skin disease, more primers should be used to find gene related with red skin disease.

• Journal of the Society of Naval Architects of Korea
• /
• v.51 no.5
• /
• pp.419-428
• /
• 2014

This paper presents a numerical simulation method for the flow around advancing ships in regular waves by using a rectilinear grid system. Because the grid lines do not consist with body surface in the rectilinear grid system, the body geometries are defined by the interaction points of those grid lines and the body surface. For the satisfaction of body boundary conditions, no-slip and divergence free conditions are imposed on the body surface and body boundary cells, respectively. Meanwhile, free surface is defined with the modified marker density method. The pressure on the free surface is determined to make the pressure gradient terms of the governing equations continuous, and the velocity around the free surface is calculated with the pressure on the free surface. To validate the present numerical method, a vortex induced vibration (VIV) phenomenon and flows around an advancing Wigley III ship model in various regular waves are simulated, and the results are compared with existing and corresponding research data. Also, to check the applicability to practical ship model, flows around KRISO Container Ship (KCS) model advancing in calm water are numerically simulated. On the simulations, the trim and the sinkage are set free to compare the running attitude with some other experimental data. Moreover, flows around the KCS model in regular waves are also simulated.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.277-277
• /
• 2022

Lignin modification has been a breeding target for the improvements of forage digestibility and fermentation in whole crop silage(WCS) rice. In rice, gold hull and internode 2 (gh2) was identified as a lignin-deficient mutant. gh2 exhibits a reddish-brown pigmentation in the hull and the internode is located on the short arm of chromosome 2 and codes for cinnamyl-alcohol dehydrogenase (CAD). To develop WCS rice variety improved digestibility and fermentation, we measured acid detergent fiber (ADF), lignin and total digestible nutrient (TDN) calculated from ADF (TDN=88.9-(0.79% × ADF) and performed marker-assisted selection using CAD(Os2g0187800) gene first intron region specific marker with 55 Jungmo1038/J.collection lines. Those lines had lignin content range from 0.82 to 6.61%, ADF from 15.8 to 45.8%, TDN from 52.7 to 78.8 compared to 'Jungmo1038'(1.53,20.7,72.6), 'J.collection'(0.98,12.8,78.8%) and gh2 were introgressed into 44 lines. Considering on these genotype and low-lignin phenotype, we finally selected 2 elite lines(Suweon668, Suweon669). Suweon668 and Suweon669 line are high biomass-low lignin lines that the ADF content is relatively low, even though the dry matter weight is high. Also they have lodging and shattering resistance and glabrous leaf and hull important to improve cattle palatability. Our results will provide that rice can be improved for forage digestibility and fermentation with low lignin concentration.

• Journal of Life Science
• /
• v.24 no.6
• /
• pp.618-625
• /
• 2014

Rice flour is used in many food products. However, dough made from rice lacks extensibility and elasticity, making it less suitable than wheat for many food products such as bread and noodles. The high-molecular weight glutenin subunits (HMW-GS) of wheat play a crucial role in determining the processing properties of the wheat grain. This paper describes the development of marker-free transgenic rice plants expressing a wheat Glu-Dy10 gene encoding the HMG-GS from the Korean wheat cultivar 'Jokyeong' using Agrobacterium-mediated co-transformation. Two expression cassettes, consisting of separate DNA fragments containing Glu-1Dy10 and hygromycin phosphotransferase II (HPTII) resistance genes, were introduced separately into Agrobacterium tumefaciens EHA105 for co-infection. Each EHA105 strain harboring Glu-1Dy10 or HPTII was infected into rice calli at a 3: 1 ratio of Glu-1Bx7 and HPTII. Among 290 hygromycin-resistant $T_0$ plants, we obtained 29 transgenic lines with both the Glu-1Dy10 and HPTII genes inserted into the rice genome. We reconfirmed the integration of the Glu-1Dy10 gene into the rice genome by Southern blot analysis. Transcripts and proteins of the Glu-1Dy10 in transgenic rice seeds were examined by semi-quantitative RT-PCR and Western blot analysis. The marker-free plants containing only the Glu-1Dy10 gene were successfully screened in the $T_1$ generation.

• Journal of Plant Biotechnology
• /
• v.29 no.3
• /
• pp.151-159
• /
• 2002

Genetic map and molecular marker have a great importance in improving and facilitating crop breeding program as well as in genome analysis and map-based cloning of genes representing desirable characters. This study aimed at developing RAPD markers and constructing a genetic linkage map using 82 BC$_1$F$_1$individuals originated from the cross between '835' and B$_2$in radish (Raphanus sativus L.). One of the parents for genetic linkage map construction, '835'(P$_1$) of egg type is susceptible to Fusarium wilt and have medium resistance to virus infection and the other parent, B$_2$(P$_2$) of round type, is susceptible to Fusarium wilt and virus, Screening of 394 RAPD primers in BC$_1$F$_1$) population resulted in selecting 128 polymorphic markers which displayed 1:1 segregation pattern. Two markers failed to display 1:1 segregation and showed the segregation ratio skewed to maternal genotype. Selected markers were categorized into 14 linkage group based on LOD score represented by MAPMAKER/EXP program. Five groups composed of single marker among them were excluded from the linkage map, and consequently, the remaining groups are well matched with the number of radish chromosome (n＝9). The linkage map constructed with 128 markers covers 1,688.3 cM and the average distance between markers was 13.8 cM. For developing STS marker, we determined the partial nucleotide sequence of OPE10 marker at both ends and designed a oligonucleotide primer pair based on this sequence. STS PCR using the primer pair displayed a single, clear band of which segregation is perfectly matched with that of OPE10 marker. This implies that RAPD markers could readily convert into clear and reliable STS markers.

• Journal of Life Science
• /
• v.23 no.11
• /
• pp.1317-1324
• /
• 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
• /
• v.42 no.4
• /
• pp.312-325
• /
• 2015

In this review, we summarized the trends of genomics and transcriptomics research on peach, a model species of Rosaceae. Peach genome maps have been developed from various progeny groups with many next-generation sequencing (NGS) based single nucleotide polymorphism markers. Molecular markers of qualitative traits and quantitative trait loci (QTL) such as fruit characteristics, blooming date, and disease resistance have been analyzed. Among many characteristics, markers related to flesh softening and flesh adhesion are useful for marker assisted selection. Through comparative genomics, peach genome has been compared to the genome of Arabidopsis, Populus, Malus, and Fragaria species. Through transcriptomics and proteomics, fruit growth and development, and flavonoid synthesis, postharvest related transcriptomes and disease resistance related proteins have been reported. Recently, development of NGS based markers, construction of core collection of germplasm, and genotyping of various progenies have been preceded. In the near future, accurate QTL analysis and identification of useful genes are expected to establish a foundation for effective molecular breeding.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.4
• /
• pp.1325-1331
• /
• 2012

Tumor formation and growth is dictated by a very small number of tumor cells, called cancer stem cells, which are capable of self-renewal. The genesis of cancer stem cells and their resistance to conventional chemotherapy and radiotherapy via mechanisms such as multidrug resistance, quiescence, enhanced DNA repair abilities and anti-apoptotic mechanisms, make it imperative to develop methods to identify and use these cells as diagnostic or therapeutic targets. Aldehyde dehydrogenase 1 (ALDH1) is used as a cancer stem cell marker. In this study, we evaluated ALDH1 expression in CaSki, HeLa and SiHa cervical cancer cells using the Aldefluor method to isolate ALDH1-positive cells. We showed that higher ALDH1 expression correlated with significantly higher rates of cell proliferation, microsphere formation and migration. We also could demonstrate that SiHa-ALDH1-positive cells were significantly more tumorigenic compared to SiHa-ALDH1-negative cells. Similarly, SiHa cells overexpressing ALDH1 were significantly more tumorigenic and showed higher rates of cell proliferation and migration compared to SiHa cells where ALDH1 expression was knocked down using a lentivirus vector. Our data suggested that ALDH1 is a marker of cervical cancer stem cells and expand our understanding of its functional role.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.5
• /
• pp.243-248
• /
• 2001

This study was peformed to find out the optimal conditions for the selection of transformed cells using already established transgenic plants. Several transgenic poplar (Populus alba$\times$P giandulosa) lines carrying npt II or hpt gene as a selectable marker were tested against kanamycin or hygromycin. Two culture explants, leaf discs and nodes, were compared regarding their sensitivity to the antibiotics. When leaf discs of untransformed control plants were cultured on callus inducing media in the presence of varying levels of kanamycin or hygromycin, only those cultured on the media containing lower than 50 mg/L kanamycin or 2 mg/L hygromycin formed callus. However, much higher concentration of kanamycin was needed to suppress the growth of axillary buds of untransformed plants. On the other hand, hygromycin at the concentration of 5 mg/L effectively suppressed shoot growth of untransformed plants. Root induction from untransformed plants could also be suppressed at the concentration of 50 mg/L kanamycin or 5 mg/L hygromycin. The transgenic plants showed resistance to 100 mg/L kanamycin or 50 mg/L hygromycin in the growth of callus, shoots, and roots. Hygromycin appeared to be more efficient in selecting untransformed cells than kanamycin.

• Journal of Plant Biotechnology
• /
• v.33 no.4
• /
• pp.271-276
• /
• 2006

Hypocotyl explants of Chinese cabbage (us. 'Jeong Sang' and 'Seoul') produced adventitious shoots on Murashige and Skoog (MS) basal medium supplemented with 4mg/L $AgNO_3$, 5 mg/L acetosyringone, 4 mg/L 6-benzyladenine and 3mg/L alpha-naphthaleneacetic acid (SI) after cocoultivation with strains of Agrobacterium tumefaciens (LBA4404) harboring the pCAMBIA1301 and the $_PPTN290$ containing hygromycin-resistance gene and paromomycin-resistance gene as a selectable marker genes, respectively. There was a significant difference in the frequency of transgenic plants depending on antibiotics and cultivars used. Paromomycin was better than hygromycin, and cultivar 'Jeong-sang' was higher than 'c.v. Seoul' in the frequency of transgenic plants. In particular, the highest frequency (0.70%) of transgenic plants was obtained from selection medium (SI) containing 100mg/L paromomycin in c.v., 'Jeong-sang' GUS positive response were obtained 9 plants and 3 plants from the cultivars, 'Jeong-sang' and 'Seoul', respectively. They were grown to maturity in a greenhouse and normally produced $T_1$ seeds. GUS histochemical assay for progeny $(T_1)$ revealed that the transgenes were expressed in the plant genome.