• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.379-384
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• 1997

Superovulation with exogenous gonadotropins creates a spectrum of pre or periovulatory hormonal changes with subsequent detrimental effects on oocyte quality, fertilization, embryo development, implantation and maintenance of pregnancy. Our recent study determined potential roles for insulin-like growth factor-1 (IGF-1) in uterine environment regulation and preimplant tation in the rat. The evidence indicates that IGF-l may play an important role in the main tenance of a receptive uterine environment for embryonic development and the regulation of decidualization. Embryonic loss and failure of implantations following superovulation may be partially attributed to disturbances in uterine IGF-l action as observed in this study. We investigated the effects of superovulatory doses of gonadotropins on frequency of chromosomal a abnormalities of mouse embryos. Chromosome a analysis of mouse zygotes and 8- to 16-cell stage embryos from spontaneously ovulated, 5, 10, and l 15 lU pregnant mare serum gonadotropin (PMSG) superovulated mice was carried out. Aneuploidy, polyploidy and structural chrom- osomal abnormalities were detected among the four groups. However, only polyploidy was correlated with superovulation. In 10 and 15 IV PMSG treated groups, the rate of polypoidy was 2.9% and 10.5%, respectively. Furthermore, there was a dose reponse relationship between the PMSG dose and the incidence of embryonic p polyploidy (P

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.281-287
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• 1999

Codonopsis lanceolata ("Deoduck" in Korea) is a perennial herb, and belongs to family, Campanulaceae. Its taproot is used a good source of a wild vegetable as well as an herbaceous medicine. In this study, to develop a bialaphos-resistant transgenic Codonopsis, seed germination mechanism and somatic embryogenesis of the plant were investigated, and Agrobacterium-mediated transformation with bar gene encoding phosphinothricin acetyltransferase (PAT) was performed. Attempt were made to regenerate plant from cells via somatic embryogenesis. When the cotyledons, nodes and leaf disks were cultured on MS medium containing 2,4-D and zeatin, embryogenic calli were induced. Upon transferring the somatic embryos to N6 solid medium without plant growth regulators, they developed into plantlets under continuous illumination. All plants were dead on MS basal medium containing 10 mg/L phosphinothricin (PPT) and Basta, respectively. The explants did not produce calli in the medium containing 200 mg/L kanamycin. The explants were cocultured with Agrobacterium tumefaciens for 2 days, and transformants were selected in MS basal medium containing 1.0 mg/L 2,4-D, 100 mg/L kanamycin and 500 mg/L carbenicillin. After the selection, embryogenic calli were induced and then somatic embryos were produced by subsequent subculturing. The somatic embryos were germiated on N6 basal medium containing 200 mg/L kanamycin and 500 mg/L carbenicillin. PCR analysis showed that nptII and bar genes were introduced in the Deoduck transformants. After the confirmation of bar gene expression in RNA and protein level, the transgenic Deoduck will be used to study the genetics of filial generation with the herbicide control gene, bar.gene, bar.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.1-5
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• 2007

The Precesses for leaf development in dicotyledonous plants are surprisingly complex, while the mechanism of controlling and coordinating them is poorly understood. To characterize the fundamental features of the leaf development of Arabidopsis, we first attempted to isolate mutants that alter leaf morphology. Here, leaf morphological mutant of Arabidopsis, lanceolatal (lan1) which has small and narrow leaves have isolated and characterized. To clarify the function of LAN1 in organ development, we characterized lan1-7 mutant using an anatomical and genetic approach. The lan1-7 mutant had reduced size of foliage leaves and reduced dimensions of stems. A reduction both in cell size and in cell number was evident at the cellular level in the lan1 mutant, revealing that LAN1 gene appears to affect cell division at an earlier stage and cell elongation throughout the development of leaf primordia. from the analysis of heterogeneous plant with lan1 mutation and 35S-AG transgenic plant, AG gene is revealed to regulate leaf morphology under the control of 35S promoter. Thus, MADS-box gene was revealed to have some relationship to that of LAN1 gene at certain stage in leaf development processes.

• Journal of Plant Biotechnology
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• v.49 no.1
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• pp.74-81
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• 2022

Brassica napus, an oil crop that produces rapeseed oil, is an allotetraploid (AACC, 2n = 38) produced by natural hybridization between B. rapa and B. oleracea. In this study, microspore was cultured using the F₁ developed from a cross between 'EMS26' line with high oleic acid content and 'J8634-B-30' lines. The flower bud size showing the nuclear development at the late uninucleate and binucleate stage with high embryogenesis rate was 2.6 ~ 3.5 mm. Microspores were cultured using only this size and after then most microspore embryo developed into secondary embryos and then regeneration plants obtained from the developed multilobe. The analysis of the ploidy of the plants revealed that 66.7% and 27.8% of the total lines were tetraploids and octoploids, respectively. The sizes of stomatal cells in tetraploids, octoploids, and diploids were 25.5, 35.6, and 19.9 ㎛, respectively, indicating that ploidy level was positively correlated with cell size. Furthermore, 62 tetraploid doubled haploid (DH) lines were selected. The average oleic acid (C18:1) and linolenic acid (C18:3) concentrations of DH were 72.3% and 6.2%, respectively. Oleic acid and linolenic acid concentrations exceeded the two parental values in 5 and 14 DH lines, respectively, suggesting that these two fatty acids had transgressive segregation. Therefore, the DH population can be utilized for the biosynthesis of unsaturated fatty acids in rapeseed and related genes. It can also be used as a breeding material for varieties with high oleic acid concentrations.

• Journal of Life Science
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• v.13 no.3
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• pp.314-323
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• 2003

The purpose of this study was to examine the effects of xenobiotic nuclear receptors, CAR, SXR, and PPAR${\gamma}$ on the transcriptional activity of estrogen receptor in human breast cancer cell lines and compare with those in human hepatoma cell line. Two different breast cancer cell lines, MCF-7 and MDA-MB-231 were cultured and effects of CAR, SXR, and PPAR${\gamma}$ on the ER-mediated transcriptional activation of synthetic (4ERE)-tk-luciferase reporter gene were analyzed. Consistent with the previous report, CAR significantly inhibited ER-mediated transactivation and SXR repressed modestly whereas the PPAR${\gamma}$ did not repress the ER-mediated transactivation. However, in breast cancer cells neither of the xenobiotic receptors repressed the ER-mediated transactivation. Instead, they tend to increase the transactivation depending on the cell type and xenobiotic nuclear receptors. In MCF-7, SXR but neither CAR nor PPAR${\gamma}$ slightly increased ER-mediated transactivation whereas in MDA-MB-231, CAR and PPAR${\gamma}$ but not SXR tend to increase the transactivation of the reporter gene. These results indicate that the effects of ER cross-talk by the CAR, SXR, and PPAR${\gamma}$ , are different in breast cancer cells from hepatoma cells. In conclusion, the transcriptional regulation by estrogen can involve different cross-talk interaction between estrogen receptor and xenobiotic nuclear receptors depending on the estrogen target cells.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.155-160
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• 2001

Changes in genetic diversity after seed-tree practice were simulated in test plantation of tulip tree at Sokdal-ri, Banwol-myon, Hwasung-gun, Kyungki Provence. I-SSR markers were analyzed in a total of 305 tulip trees. A total of 89 amplicon variants were observed by PCR with 9 I-SSR primers. Genetic diversity for 305 trees was relatively high (S. I. =0.4532). Individuals originated from the seed orchards in U.S.A. showed the highest level of genetic diversity (0.4530), those from Anyang showed the medium level (0.4152), and those from Cheonbuk showed the lowest (0.3929). Simulation of seed-tree practice accompanied by 2 consecutive thinnings was performed on the basis of morphological characteristics and planted distances of the individual trees, which left 37 trees as candidates for seed-trees. Decreasing rate of genetic diversity within seed sources was greatest for individuals from Cheonbuk (28.3%), moderate for those from Anyang (16.3%), and smallest for those from U.S.A. (8.0%). In spite of little difference in decreasing rate of individuals for the 3 seed sources (87.5~88.2%), large difference in decreasing rate of genetic diversity within seed sources might be due to difference in number of mother trees for the 3 seed sources. For example, whereas individuals originated from the seed orchard in U.S.A., which showed the smallest decreasing rate of genetic diversity, might be originated from relatively large number of mother trees, those from Anyang and Cheonbuk might be originated from relatively small number of mother trees. Although mean of 17.5% of the genetic diversity within seed sources was decreased through 2 consecutive thinnings, a decrease in genetic diversity for the whole individuals (37 trees) was only 6.1%. This observation suggests that the seed-tree practice on the basis of the criteria established in the present study may not result in great reduction in overall genetic diversity of the progenies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.473-480
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• 1983

To obtain basic information on the Korean local com lines a total of 57 lines were selected from 1,000 Korean local collection at Chungnam National University, and classified by principal component analysis, and genetic nature was investigated. There were a great variation in mean values of plant characters of the lines. The mean values of plant characters except for density of kernels varied with types of crossing. All characters except for tasselling dates were reduced in magnitude when selfed, while those characters were increased when topcrossed. The inbreeding depression varied with plant characters and lines. The characters such as yield, kernel weight per ear, ear weight and plant height showed great degree of inbreeding depression. Group I showed high inbreeding depression in such characters as 100 kernel weight, leaf number, plant height and days to tasselling, while group II showed high inbreeding depression in other plant characters. Heterosis of plant characters varied also with lines. The ear weight, kernel weight per ear, yield, 100 kernel weight, and plant height were some of the plant characters showing high heterosis. Group II showed high values of heterosis in such characters as ear length, ear diameter, ear weight, kernel weight per ear, 100 kernel weight and leaf length, while group I was high in heterosis in other plant characters. The degree of homozygosity was highest in ear weight (79.1%) and lowest in ear number per plant (-2.1%). Group II showed higher degree of homozygosity than group I. Correlation coefficients between characters of sibbed and topcrossed lines were positive for all characters. Highly significant correlation coefficients between sibbed and topcrossed lines were obtained especially for characters such as ear number per plant, plant height, leaf length and yield per plot.

• Development and Reproduction
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• v.6 no.2
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• pp.71-76
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• 2002

Present study was aimed to summary the recent reports of chromosomal technology such like a polyploidv, sex differentiation, gynogenesis, transgenic fish and gene manipulation. Triploid cells for rainbow trout and channel catfish were induced through thermal shocks of varying temperature levels and produced as a industrial use. A monosex fish with homogametic females of 15 species of high valued fish were produced by exposing to irradiation. It seemed that different irradiation was suitable to inactivate the sperm and block the formation in producing the gynogenetic diploids. Since 1985, transgenic fish have been successfully produced by microinjecting or electroporating desired foreign DNA into unfertilized or newly fertilized eggs using about 40 fish species. More recently, transgenic fish have also been produced by infecting newly fertilized eggs with pantropic, defective retroviral vectors carrying desired foreign DNA. These transgenic fish can serve as excellent experimental models for basic scientific investigations as well as in marine biotechnological applications.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.409-413
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• 2015

To enhance phytoremediation, which removes heavy metal from soil, transgenic plants were applied to contaminated soil. We constructed a transformation vector expressing both $TgMTP_1$ (T. goesingense metal tolerance protein):HA and TgMTP:GFP genes. Transgenic plants were generated using an Agrobacterium-mediated transformation system that expressed the two vectors. Screening and analysis confirmed the incorporation of foreign genes into the Arabidopsis thaliana genome. Callus was induced in the 116 T3 line. These transgenic plants and calli were used for further analyses on the accumulation of Ni. The 116 T3-line plants and calli from selected lines were resistant to heavy metals and accumulated Ni in their leaves. The expression level of TgMTP RNA was equal in all leaves, but protein stability increased in the leaves with Ni treatment. According to these results, we suggest that $TgMTP_1$-overexpressing plants may be useful for phytoremediation of soil.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.6
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• pp.595-601
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• 2013

This paper presents an optimized design of a millimeter-wave on-chip dipole antenna using CMOS process. The serious flaw of the antenna using CMOS process is low radiation efficiency because of high permittivity and conductivity. To overcome the weakness, we need to widen radiation area in air and optimize distance between an antenna and a reflector. The radiation efficiency and bandwidth of the designed antenna are respectively 16.5 % and 22.3 % at 80 GHz. Systematic methods are attempt to analyze an effect on the antenna radiation efficiency. To widen radiation area in air, substrate cut angle and distance between the antenna and chip edge are adjusted. In addition, to optimize distance between an antenna and reflector, substrate thickness and distance between the antenna and a circuit ground plane are adjusted.