• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.563-569
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• 2007

RAPD analysis showed that all the OTUs of 'Sandolbae' were the same species because amplified band patterns of all samples generated by each of 5 random primers were identical. Even though there were different environmental conditions, all the "Chuiangne" trees from three different places were the same species, and also all the "Cheongshilli" trees were the same species too. No genetic variations were detected between native Korean pears grown in the habitats and in the research field. Because 212 polymorphic bands were generated by 9 primers selected through primer screening, they were possible to analyze genetic relationship among naturally growing three native Korean pears and nine cultivars of Pyrus pyrifolia and P. communis. Based on the RAPD analysis, three main groups were formed. The first group represented the Six P. pyrifoia cultivars, the second group was the three native Korean pears, and the last group was the three P. communis cultivars. Genetic distance between 'Wonwhang' and 'Chojuro' was closer than other cultivars in group 1 since dissimilarity index value between these two cultivars was 50.82. However, genetic distance between 'Niitaka' and 'Chojuro' was the most distant compared to the others in group 1. In group 2, 'Sandlobae' was genetically closer to 'Chuiangne' than 'Cheongshilli' because dissimilarity index value between 'Sandlobae' and 'Chuiangne' was smaller, 50.82, than the value between 'Sandlobae' and 'Cheongshilli', 63.636. In group 3, 'Old Home' was genetically closer to 'Bartlett' than 'Kaiser Alexander(or Bosc)'. Group 3 composed of P. communis cultivars was genetically further than other two groups, P. pyrifolia cultivars and native Korean pears.

• BMB Reports
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• v.28 no.1
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• pp.33-39
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• 1995

The Gelatinases (typeIV collagenases) are metalloproteinases that may play an important role in tumor invasion and metastasis. Progelatinase A was purified from a conditioned medium of T98G human glioblastoma cells. TIMP-2 complexed progelatinase A and free progelatinase A were separated by heparin affinity HPLC. The final product was homogeneous on SDS-PAGE, with a molecular weight of 64,000 daltons without reduction. TIMP-2 and free progelatinase A were separated from TIMP-2 complexed progelatinase A by reverse-phase HPLC in the presence of trifluoroacetic acid. TIMP-2 complexed progelatinase A was resistant to activation by p-aminophenyl mercuric acetate (APMA), and showed less than 20% of the activity of the TIMP-2 free active enzyme. TIMP-2 free progelatinase A was easily activated to the mature form with a molecular weight of 57,000 daltons by APMA and showed high activity compared to the TIMP-2 complexed enzyme.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.104-110
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• 2000

To analyse the genetic relationship and intraspecific variations among the Eleutherococcus senticosus population, the polymerase chain reaction(PCR) was performed total genomic DNAs of 10 E. senticosus collections by random 10 primers. The genetic diversity and genetic distance among 10 collections of Eleutherococcus spp. were used to describe the dendrogram showing phylogenic relationship. Ten collections were classfied into two group(group I, II) at the similarity coefficient value of 0.50. Group I included E. senticosus of Bukhado(Japanese), youngwal(Korea), E. seoulense, and E. chiisanesis while group II included several internal and Russia collection. The range of polymorphism was from 66.7 to 90.9% in 87 amplified DNA fragments. The similarity value of all collections ranged from 0.41 to 0.92. The average of genetic distance was 0.61.

• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.119-133
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• 1997

Isozyme was used to characterize general protein patterns of genetic relationships among 303 silkworm stocks preserved in National Sericultural and Entomology Research Institute, RDA. Six isozymes (esterase, acid phosphatase, alkaline phosphatase, amylase, glucose-6-phosphate dehydrogenase and sucrase) from hemolymph, midgut, and digestive juice were employed to construct dendograms(UPGMA method) using a polycrylamide gel electrophoresis. A cluster analysis revealed four major group, which were divided into several subgroups within each group, contained assemglages of Japanese and Chinese races. Especially, genetic differentiation in the first and second group was greatest rather than within Japanese and Chinese races repectively and was concordant with the hypothesis of phyletic sorting of initial variability in China many years ago. Hypothesized recent introgression between groups was also plausible, but the eviednce suggested bidirectional gene flow between the Chinese and the Japnaese lineages. Interpreting the results in light of evidence from the current study, the genetic diversity and relationship showed in Korean silkworm race, Hansammyun reflected early and independent evolution from the Chinese ancestor, limited addition of new variability and phyletic sorting within Korean peninsula more than 4,000 years.

• Plant Resources
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• v.6 no.1
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• pp.16-26
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• 2003

Molecular markers are useful tools for evaluating genetic diversity and determining cultivar identity. Present study was conducted to evaluate the genetic diversity within a diverse collection of rice accessions used for Korean breeding programs. Two hundred eighty-seven rice cultivars, composed of temperate japonica, tropical japonica, indica, and Tongil-type of Korean crossing parents were evaluated by means of 15 simple sequence repeat (SSR) markers. A total of 99 alleles were detected, and the number of alleles per marker ranged from 4 to 11, with an average of 6.6 per locus. Polymorphism information content (PIC) for each of the SSR markers ranged from 0.2924 to 0.8102 with an average of 0.5785. These results, with the result that use of only 15 SSR markers made all rice cultivars examined could be uniquely distinguished, imply the efficiency of SSR markers for analysis of genetic diversity in rice. Cluster analysis was performed on similar coefficient matrics calculated from SSR markers to generate a dendogram in which two major groups corresponding to japonica (Group I) and indica and Tongil type rice (group II) with additional subclasses within both major groups. The narrowness of the Korean breeding germplasm was revealed by the fact that most of the Korean-bred and Japan-bred temperate japonica cultivars were concentrated into only 2 of the sub-group I-1 (143 cultivars) and I-2 (58 cultivars) among six sub-groups in major group of japonica. This is because of the japonica accessions used in this study was a very closely related ones because of frequent sharing of the crossing parents with similar genetic background with synergy effect of the inherited genetic difference between indica and japonica. A rice breeding strategy with the use of molecular markers was discussed for overcoming of genetic vulnerability owing to this genetic narrowness.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.234-236
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• 1994

During the screening of insecticidal compounds from soil microorganisms, SR 2077 was isolated from the metabolites of Actinomycetes isolate No. 2077 and identified as albocycline by UV and NMR data analyses.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.285-289
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• 1994

An insecticidal crystal protein gene, cryIA(c), from Bacillus thuringiensis HD-73 was integrated into the chromosome of a xanthan-producing bacterium, Xanthomonas campestris XP92. The cryIA(c) gene expression cassette was constructed that placed the gene between the trc promoter and rrnB transcriptional terminator. The $lacl^q$ gene was also included to prevent the expression of cryIA(c) gene in X campestris cells. Southem blot analysis confirmed the integration of the cryIA(c) gene expression cassette in chromosome of X campestris XP92 transconjugant. Expression of the insecticidal crystal protein was confirmed by Western blot analysis and bioassay against the larvae of Hyphantria cunea (Lepidoptera： Arctiidae) and Plutella xylostella (Lepidoptera：Plutellidae).

• Journal of Embryo Transfer
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• v.24 no.3
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• pp.199-205
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• 2009

This study was carried out to investigate the effective genetic resources preservation system using the frozen boar semen. The porcine oocytes were matured for 44 hours in NCSU-23 medium with or without 10% Porcine Follicle Fluid (PFF), 0.5 ${\mu}g/ml$ porcine FSH, 0.5 ${\mu}g/ml$ equine LH, 1.0 ${\mu}g/ml$ 17 $\beta$-estradiol ($E_2$) and 10 ng/ml Epidermal Growth Factor (EGF) under mineral oil at $38.5^{\circ}C$ in humidified atmosphere of 5% $CO_2$ in air. After 44 h of culture, the oocytes were inseminated with frozen-thawed semen and fresh semen prepared with mTBM medium for 6 h. Later, set of 50 presumptive zygotes were transferred into 4-well dish (500 ${\mu}l$) of IVC medium. for embryos freezing, slow-freezing and vitrification methods were used as a cryopreservation. Differences among treatments were analyzed using General Linear Model Procedure by SAS Package (version 6.12) differences were considered significant when p<0.05. Following IVF and IVC, the rates of cleavage and blastocysts formation were significantly higher (p<0.05) in hormone supplemented group than that of hormone-free group (25.7 vs, 12.1). The development rates to cleavage and blastocysts were significantly higher in PZM-5 group than NCSU-23 group (60.3%, 46.6% vs 27.4%, 11.1%). Further improvement was achieved when PZM-5 was supplemented with FBS. Cleavage rates was significantly higher in fresh semen source group than frozen semen (66.7% vs 43.7%). However in blastocysts rates was similar two groups. Post-thaw survival rates of embryos were 1.2% and 2.2% in slow-frezing and vitrification groups, respectively. The results of our study suggest that it is still possible to improve the culture conditions and boar semen cryopreservation for enhance reproductive technology and animal genetic resources conservation.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.250-257
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• 2008

Knowledge of genetic diversity and of the genetic relationships among elite breeding materials has had a significant impact on the improvement of crops. In maize, this information is particularly useful in i) planning crosses for hybrid and line development, ii) in assigning lines to heterotic groups and iii) in plant variety protection. We have used the SSR technique to study the genetic diversity and genetic relationships among 76 Korean waxy corn accessions, representing a diverse collection from throughout Korea. Assessment of genetic diversity among members of this group was conducted using 30 microsatellite markers. Among these 30 microsatellite markers, we identified a total of 127 alleles (with an average of 4.2 and a range of between 2 and 9 alleles per locus). Gene diversity at these 30 microsatellite loci varied from 0.125 to 0.795 with an average of 0.507. The cluster tree generated with the described microsatellite markers recognized two major groups with 36.5% genetic similarity. Group I includes 63 inbred lines, with similarity coefficients of between 0.365 and 0.99. Group II includes 13 inbred lines, with similarity coefficients of between 0.45 and 0.85. The present study indicates that the 30 microsatellite loci chosen for this analysis are effective molecular markers for the assessment of genetic diversity and genetic relationships between Korean waxy corn accessions. Specifically, this study's assessment of genetic diversity and relationships between a set of 76 Korean waxy corn inbred lines will be helpful for such activities as planning crosses for hybrid and line development and association mapping analyses of maize breeding programs in Korea.

• Journal of Information Technology Application
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• v.3 no.3
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• pp.25-40
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• 2001

This paper deals with the problem of generating optimal polynomials using Genetic Programming(GP). The polynomial should approximate nonlinear response surfaces. Also, there should be a consideration regarding the size of the polynomial, It is not desirable if the polynomial is too large. To build small or medium size of polynomials that enable to model nonlinear response surfaces, we use the low order Tailor series in the function set of GP, and put the constrain on generating GP tree during the evolving process in order to prevent GP trees from becoming too large size of polynomials. Also, GAGPT(Group of Additive Genetic Programming Trees) is adopted to help achieving such purpose. Two examples are given to demonstrate our method.