• Journal of Life Science
• /
• v.14 no.3
• /
• pp.375-384
• /
• 2004

Fibroblast growth factors (FGFs) are known to induce multiple functions in early development, including mesoderm formation, gastrulation movement and antero-posterior patterning. The induction of mesoderm from Xenopus presumptive ectoderm and the combination effect on inducing organs of bFGF(basic FGF) and HGF (Hepatocyte Growth Factor) were studied. Explants were cultured in the combined solution for 3 days to normal embryo arrive at St. 43. These effects on combined dose were examined by histological experiment and by immunohistochemical method. The concentrations of growth factors were tested in 0, 0.5, 1, 10 and also tested in 50 ng/ml of bFGF, and 0, 1, 10, 50 and 100ng/ml of HGF respectively. The synergistic effects were seen in the combined-dose of bFGF and HGF rather than in single dose. Various organs were differentiated and highest inducing effects were seen at the combined concentration of 1 ng/ml of bFGF and 10ng/ml of HGF, and at the concentration 10ng/ml of bFGF and 1 ng/ml of HGF. The bFGF induces various organs from cultured animal cap explants and the effects are time and dose-dependent. HGF is also a potent mitogen for renal tubular cells and for mature hepatocytes in primary culture. Eyes were developed in high percentage at the combined concentration of 1 and 10ng/ml of bFGF, and 1 and 10 ng/ml of HGF. From the induced eye and normal embryonic eye, RPE65 was commonly detected by monoclonal antibodies 40All and 25F5 and the localization of RPE65 was seen by AP reaction.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.39 no.2
• /
• pp.180-186
• /
• 1994

Lipoxygenase activity of soybean seeds of approximately 507 genotypes as well as its inheritance and selection efficiency in early breeding generation was measured in the Department of Agronomy, Seoul National University to facilitate breeding for low lipoxygenase activity of soybean. Average seed lipoxygenase activity of 507 cultivars and strains was 350 unit (unit: $\Delta$0.01 /min. /mg at 234nm) and ranged from 50 to 670 unit. There was no difference in mean lipoxygenase activity according to apparent seed characters such as seed coat and embryo color. But early mature soybean genotypes had fairly low lipoxygenase activity. Lipoxygenase activity was inherited quantitatively, in which additive effect was greater than dominant one and proportion of gene with positive effects was similar to that with negative ones. Estimated narrow- and broad-sense heritabilities were 0.78 and 0.86 for lipoxygenase activity, respectively. Heritability measured from selection in early breeding lines for high or low lipoxygenase activity was 64~76% or 54~62%, respectively. And selection for high lipoxygenase activity increased by 29.7~44.7%, whereas that for low ones decreased by 21.8~27.3%, respectively, when compared to random population. Clear effect in selecting of lipoxygenase activity was present in early generation.

• Development and Reproduction
• /
• v.8 no.1
• /
• pp.35-42
• /
• 2004

Oocyte maturation refers to the process that prophase I arrested germinal vesicle(GV) drives the progression of meiosis to metaphase II(MII) to have the capacity for fertilization and embryo development. To better understand the molecular mechanism(s) involved in oocyte maturation, we identified differentially expressed genes(DEGs) between GV and MII mouse oocytes using a new innovative annealing control primer (ACP) technology. Using 20 ACPs, we successfully cloned 32 DEGs between GV and Mll oocytes, and 26 out of these 32 DEGs were functionally known genes. Four genes including Pscd2 were GV-specific, 10 genes including PKD2 and CSN3 were highly expressed in GV oocytes(GV-selective), and 12 genes including Diva were highly expressed in MII oocytes (MII-selective). Ail of the genes identified in this study were first reported in the oocyte expression using ACP system and especially, we could characterize the existence of PKD-CSW signaling pathwayin the mouse oocytes. Results of the present study would provide insight for studying molecular mechanisms regulating oocyte maturation.

• Korean Journal of Ichthyology
• /
• v.23 no.3
• /
• pp.198-205
• /
• 2011

Early life history of the endangered species, Gobiobotia macrocephala was investigated to provide baseline data for biological characteristics and recovery. Adult fish were sampled by spoon net at Hongcheon-gun, Gangwon-do, Korea in April to June 2010. The female's eggs were obtained by injecting Ovaprim and fertilized by dry method in the laboratory. The mature eggs were slightly adhesive and transparent with greyish and average 0.89${\pm}$0.04mm in diameter. The hatching of the embryo took place in about 107 hours after fertilization under water temperature of 23$^{\circ}C$ and newly hatched larvae were average 4.6${\pm}$0.16mm in total length. At 4 days after hatching, they were average 6.1${\pm}$0.20mm in total length and their yolk sacs were completely absorbed. From 15 days after hatching, they entered the juvenile stage and reached at 8.6${\pm}$0.67mm in total length. At the 100 days after hatching, their band patterns and external form were similar to those of adults, and they averaged 31.5${\pm}$3.32mm in total length.

• Korean Journal of Ichthyology
• /
• v.28 no.3
• /
• pp.156-163
• /
• 2016

Egg development and early life history of Korean southern spine loach, Iksookimia hugowolfeldi, were observed in the present study. Eggs were obtained after injecting females with 0.5 mL/kg of Ovarprim. Eggs were artificially fertilized using the dry method in the laboratory. Number of spawned eggs were $1,933{\pm}530per$ individual. Mature eggs were slightly adhesive with light yellowish coloring, and they measured $1.35{\pm}0.03mm$ in diameter. Hatching of the embryo occurred 56 h (50%) after fertilization at water temperature $25^{\circ}C$, and newly hatched larvae were averaged of $5.6{\pm}0.18mm$ in total length. At 5 days after hatching, larvae averaged $7.8{\pm}0.31mm$ in total length and their yolk sacs had been completely absorbed. Beginning at 15 days after hatching, the fish entered the juvenile stage and reached $13.2{\pm}0.87mm$ in total length. At 100 days after hatching, the band patterns and external form of juvenile were similar to those of adults, and they averaged $49.2{\pm}4.29mm$ in total length.

• Korean Journal of Ecology and Environment
• /
• v.45 no.1
• /
• pp.93-101
• /
• 2012

In the present study, egg development and early life history of Korean spined loach, $Iksookimia$ $koreensis$, were observed. Adult fish were sampled using spoon nets in Okgye-ri, Hoengseong-gun, Gangwon-do, Korea in July 2010. Eggs were obtained after injecting females with Ovarprim. Eggs were then artificially fertilized in the laboratory using the dry method. Mature eggs were slightly adhesive and transparent with a light yellowish color, and measured $1.40{\pm}0.04mm$ (mean${\pm}$SD) in diameter. Hatching of the embryo occurred approximately 50 h after fertilization in the water at $23^{\circ}C$, and newly hatched larvae were averaged $4.7{\pm}0.21mm$ in total length. 5 days after hatching, the averaged total length of larvae was $7.1{\pm}0.25mm$ and their yolk sacs had been completely absorbed. 17 days after hatching, fish started to enter the juvenile stage and reached $12.2{\pm}1.10mm$ in total length. 80 days after hatching, the band patterns and external form of juvenile fish were similar to those of adults, and they averaged $31.0{\pm}3.98mm$ in total length.

• Journal of Ginseng Research
• /
• v.23 no.3 s.55
• /
• pp.130-134
• /
• 1999

Somatic embryos were induced directly from cotyledon explants of Korean ginseng (Panax ginseng C.A. Meyer) on Murashige and Skoog (MS) medium with 2,4-D, BAP, kinetin or lacking growth regulators. When somatic embryos formed on all media grew to cotyledonary stage, the further development of embryos was ceased and remained in white color. By gibberellic acid (over 1.0 mg/1 $GA_3$) treatment, all the somatic embryos turned rapidly to green and germinated within 3 weeks. Chilling treatment also induced the germination of somatic embryos. The effective temperature regime was $-2^{\circ}C$ for over 8 weeks but more higher temperature than $0^{\circ}C$ did not effective for germination of somatic embryos. Ultrastructural observation revealed that the cotyledon cells of somatic embryos without chilling or $GA_3$ treatment contained numerous lipid reserves, dense cytoplasm, proplastids and non-activated mitochondria with poorly differentiated internal structure, but the cotyledon cells of germinating somatic embryos after chilling or $GA_3$ treatment highly vacuolated and contained well-developed chloroplasts and active state of mitochondria enclosing numerous cristae. The above results indicate that in vitro developed somatic embryos of Panax ginseng may be dormant after mature similar to zygotic embryos.

• Korean Journal of Plant Taxonomy
• /
• v.40 no.4
• /
• pp.226-233
• /
• 2010

An intensive study of the embryology of Gymnospermium microrrhynchum was conducted to provide information regarding a discussion of the phylogenetic relationships of the genus, which is yet unstudied. Our results indicated that Gymnospermium is similar to other genera of Berberidaceae in terms of its embryological features. Nevertheless, newly reported and unique features are the well-developed endothelium and the undifferentiated seed coat type. Until the study of Gymnospermium, it may have been considered to be closer to Caulophyllum and Leontice in the tribe Leonticeae. These three genera share many morphological features as well as molecular similarities, by which they are kept in the same tribe, Leonticeae. However, very little detailed embryological data regarding these genera have been published thus far. Gymnospermium was characterized according to the basic type of anther wall formation as well as its glandular tapetum, successive cytokinesis in the microspore mother cell, two-celled mature pollen grains, anatropous and crassinucellate ovules with a nucellar cap, well-developed endothelium, its Polygonum type of embryo sac formation, its nuclear type of endosperm formation, and its undifferentiated seed coat type. In comparison with Nandina, there are many differences, such as the dehiscence of the anther, the cytokinesis in the microspore mother cells, the shape of the megaspore dyad, and the seed characteristics. Although we had no available detailed embryological information regarding Caulophyllum and Leontice, which are genera that are more closely related to Gymnospermium, we could deduce from the phylogenetic relationship that Gymnospermium, Caulophyllum, and Leontice are more closely related to each other than other genera of Berberidaceae on the basis of the seed characteristics.

• Journal of Plant Biotechnology
• /
• v.29 no.3
• /
• pp.189-192
• /
• 2002

An efficient plant regeneration system of major cultivars of sweetpotato (Ipomoea batatas (L.) Lam.) in Korea via somatic embryogenesis was established. Embryogenic calli were formed from shoot apical meristems of sweetpotato cultivars when cultured on LS medium supplemented with 1 mg/L auxin (2,4-D, picloram, dicamba). Among three kinds of auxin, 1 mg/L 2,4-D showed the highest embryogenic calli induction rate. After 4 weeks of cultures on LS medium supplemented with 1 mg/L 2,4-D, embryogenic calli induction rates of Sinhwangmi, Zami, Yulmi, and White Star were 86%, 78%, 76%, and 80%, respectively. Upon transfer onto LS basal medium, most of somatic embryos developed into plantlets. Regenerated plantlets were transplanted to potting soil and grown to mature plants in a greenhouse.