• Title/Summary/Keyword: natural recombination

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Construction of a Transgenic Silkworm Carrying the Fibroin Gene of the Japanese Oak Silkworm, Antheraea yamamai

  • Park, Kwang-Ho;Kang, Seok-Woo;Hwang, Jae-Sam;Goo, Tea-Won;Yun, Eun-Young;Lee, Sang-Mong;Sohn, Hung-Dae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.6 no.1
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    • pp.49-55
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    • 2003
  • We describe the generation of transgenic silkworm that carrying the chimeric fibroin light chain (L-chain) gene. Previously, we have cloned the complete fibroin L-chain gene from the silkworm Baekok-Jam, Bombyx mori, and the complete fibroin gene from the oak silkworm, Antheraea yamamai. The 444 bp repetitive sequence of A. yamamai fibroin gene was inserted into the exon 6 of B. mori fibroin L-chain gene to produce chimeric fibroin L-chain gene. The chimeric fibroin L-chain gene was cloned into the polyhedrin gene site of Autographa californica nuclear polyhedrosis virus (AcNPV) to yield a recombinant baculovirus as a fibroin gene targeting vector, One-day-old fifth instar female silkworm larvae were injected with the recombinant baculovirus and then mated with normal male moths. Genomic DNA from their progenies was extracted and screened for the desired targeting event by using PCR and Southern blot analysis. The analysis showed that the chimeric fibroin gene had intergrated into the L-chain gene on the genome by homologous recombination and was transmitted through generations. The transgenic silkworm carrying the chimeric fibroin gene were approximately 43.2% in $F_2$ generation, and the silkworms synthesized the fusion protein in cocoons layer.

A Natural Hybrid of Intergeneric Mating between a Female Pungtungia herzi and a Male Pseudorasbora parva (Cypriniformes: Cyprinidae)

  • Kim, Keun-Yong;Ko, Myeong-Hun;Cho, Sung Jang;Kim, Woo-Jin;Son, Min Ho;Bang, In-Chul
    • Fisheries and Aquatic Sciences
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    • v.18 no.1
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    • pp.99-107
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    • 2015
  • A natural hybrid of a probable intergeneric mating between the striped shiner Pungtungia herzi and the stone morocco Pseudorasbora parva (Cypriniformes: Cyprinidae) was captured in the Geumho River, a tributary of the Nakdong River basin in Korea. Morphological characters and DNA sequences were analyzed to verify its hybrid state and identify the parentage of its parent species. The hybrid exhibited a phenotypic intermediacy between the two parent species in the number of vertebrae and the mouth shape. Out of 1,488 base pair (bp) positions of the nuclear recombination activating gene 1 gene (rag1), which has a biparental mode of inheritance, 41-bp substitutions were detected between the two parent species, whereas an electropherogram of the hybrid displayed polymorphic double peaks at all of the base positions, along with one additional one, strongly indicating its hybrid state. Meanwhile, sequence comparison of the mitochondrial cytochrome b gene (mt-cyb) (1,140 bp), which has a maternal mode of inheritance, showed only 5-22-bp differences (97.6-99.5% identities) between the hybrid and Pu. herzi, but as many as 158-168-bp differences (85.2-86.1% identities) between the hybrid and Ps. parva, clearly indicating Pu. herzi as the maternal species. Thus, combined analyses of independent data sets (i.e., morphology and nuclear and mitochondrial DNA sequences) offered convincing evidence for the hybrid state of a naturally occurring hybrid resulting from intergeneric mating between a female Pu. herzi and a male Ps. parva.

Characterization of Achlya bisexualis $\beta$-Amylase Expression in an Amylolytic Industrial Strain of Saccharomyces cerevisiae (전분 분해성 산업용 Saccharomyces cerevisiae에서 Achlya bisexualis $\beta$-Amylase의 발현 특성 규명)

  • Lee, Ok-Hee;Lim, Mi-Hyeon;Kim, Ji-Hye;Ryu, Eun-Hye;Ko, Hyun-Mi;Chin, Jong-Eon;Bai, Suk
    • Korean Journal of Microbiology
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    • v.44 no.3
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    • pp.264-269
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    • 2008
  • To develop an amylolytic industrial yeast strain producing $\beta$-amylase, the BAMY gene encoding Achlya bisexualis $\beta$-amylase was constitutively expressed under the control of the alcohol dehydrogenase gene promoter (ADC1p) in an industrial strain of Saccharomyces cerevisiae. Yeast transformation was carried out by an integration system containing $\delta$-sequences as the recombination site. The integrative cassette devoid of bacterial DNA sequences was constructed that contains the BAMY gene and $\delta$-sequences. Industrial S. cerevisiae transformed with this integrative cassette secreted 45 kDa $\beta$-amylase into the culture medium. The $\beta$-amylase activity of the transformant was approximately 18.5-times higher than that of A. bisexualis. The multi-integrated BAMY genes in the transform ant were stable after 100 generations of growth in nonselective medium. Hydrolysis of soluble starch and various starches with the enzyme released maltose but not glucose or oligosaccharides.

Occurrence of a Natural Intergeneric Hybrid between a Female Tanakia lanceolata and a Male Rhodeus pseudosericeus (Cypriniformes: Cyprinidae) in Daecheoncheon Stream Flowing into the Yellow Sea in the Republic of Korea (서해안 독립 하천 대천천에서 납자루 Tanakia lanceolata (♀)와 한강납줄개 Rhodeus pseudosericeus(♂)의 자연 속간잡종 출현)

  • Kim, Yong Hwi;Sung, Mu Sung;Yun, Bong Han;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.33 no.2
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    • pp.45-56
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    • 2021
  • A male, presumed to be an intergeneric hybrid between Tanakia lanceolata and Rhodeus pseudosericeus, was collected in the Boryeong Daecheoncheon Stream flowing into the Yellow Sea in the Republic of Korea. Morphological and molecular phylogenetic analyses were performed to discriminate the definite origin of the estimated natural hybrid. As a result of the morphological analysis, the color of the dorsal and anal fin rays edges of the natural hybrid individual, the upper and lower body colors followed the morphological characteristics of T. lanceolata, and that blue longitudinal stripe in the center of the caudal peduncle, the incomplete lateral line, and the barbels absent followed the morphological characteristics of R. pseudosericeus. In addition, as a result of the cytochrome b (cytb) gene analysis of mitochondrial DNA (mtDNA), the natural hybrid showed a nucleotide sequence similarity of 99.82 to 100% with T. lanceolata, and the maternal species was identified as T. lanceolata. As a result of the recombination activating gene 1 (rag1) gene analysis of nuclear DNA (nDNA), the natural hybrid showed double peaks pattern reflecting both the single nucleotide polymorphism sites (38 bp) between T. lanceolata and R. pseudosericeus, and the paternal species was identified as R. pseudosericeus. Therefore, a natural hybrid estimated male of Acheilognathinae analyzed in this study was found to be an intergeneric hybrid between a female T. lanceolata and a male R. pseudosericeus.

Analysis of Effects on the performance of ceramic metal halide lamp by the loss of elements that have been filled in arc tube

  • Jang, Hyeok-Jin;Yang, Jong-Gyeong;Lee, Jong-Chan;Kim, U-Yeong;Sin, Ik-Tae;Park, Dae-Hui
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.219-219
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    • 2009
  • ceramic metal halide lamps are a subset of high intensity discharge lamps so named because of their high radiance These lamps weak ionized plasma in a fire-resisting but light transmissive wrapping by the corridor of current through atomic and molecular vapors. for commercial applications, For commercial applications, the conversion of electric power to light must occur with good efficiency and with sufficient spectral content throughout the visible (380-800 nm) to permit the light so generated to render colors comparable to natural sunlight. the purpose of this paper is to carry out a study on the variation of ageing time(2000 On/Off[hr]) on the performance of 150W CMH lamps. Experimental results show that the blackening by reacting W(tungsten)with I atomic has been created in the arc tube of an ageing lamp(2000 On/Off[hr]), the arc was unstable, and increased a lamp resistance made lamp voltage increases significantly. Also, Color temperature of the ageing lamp was moved by the losses of Ho with Dy atomics and by recombination of Na with I.

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Study of Connection Process in Distribution systems using Genetic Algorithm (배전계통에서 GA를 이용한 접속변경 순서 결정 방법)

  • Oh, Seon;Seo, Jeong-Kap
    • Journal of Satellite, Information and Communications
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    • v.6 no.1
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    • pp.6-11
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    • 2011
  • In this paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic Algorithm (GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transferring problem to minimize load generated load point outage in each sub-section. This approach is one of the most difficult procedures and become combination problems. A new approach using GA was developed for this problem. GA is a general purpose optimization technique based on principles inspired from the biological evolution using metaphors of mechanisms such as natural selection, genetic recombination and survival of the fittest. Test results for the model system with 24 nodes 29 branches are reported in the paper.

Expressional Characteristics of Retro Image Shown on Wedding Dresses (웨딩드레스에 나타난 레트로 이미지의 표현 특성)

  • Gai, Shunan;Yoo, Youngsun
    • Journal of the Korean Society of Costume
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    • v.66 no.2
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    • pp.103-116
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    • 2016
  • This study intends to discover characteristics and methods of retro image wedding dresses by analyzing prior studies about retro characteristics. The characteristics of retro image wedding dresses are as follows: 'Recreative Retro', Trend revival Retro', 'Nostalgic Retro' and 'Remixed Retro'. The expressional characteristics and methods of each character are as follows. The 'Recreated Retro' has been recreated in the wedding dresses worn by celebrities, actresses' wedding dresses in movies, and also in the famous designer's high end wedding dresses. These dresses do not merely duplicate the originals, but also reflect images, which were reproduced by combining modern technology. The 'Trend revival Retro' emerged as a combination of past fashion styles and new trends. It seems to stimulate the customers' reminiscence of past fashion trends and create unique designs through expressing the metaphor or the adaptation of past fashion styles. The 'Nostalgic Retro' started from the discovery of emotional values for something old or the inclination to be attracted to old styles. It has been expressed through design concepts with natural themes. The 'Remixed Retro' is from recombination of Retro elements. It is shown as a new interpretative code which explains how current time blends with different times.

Alternative Production of Avermectin Components in Streptomyces avermitilis by Gene Replacement

  • Yong Joon-Hyoung;Byeon Woo-Hyeon
    • Journal of Microbiology
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    • v.43 no.3
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    • pp.277-284
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    • 2005
  • The avermectins are composed of eight compounds, which exhibit structural differences at three positions. A family of four closely-related major components, A1a, A2a, B1a and B2a, has been identified. Of these components, B1a exhibits the most potent antihelminthic activity. The coexistence of the '1' components and '2' components has been accounted for by the defective dehydratase of aveAI module 2, which appears to be responsible for C22-23 dehydration. Therefore, we have attempted to replace the dehydratase of aveAI module 2 with the functional dehydratase from the erythromycin eryAII module 4, via homologous recombination. Erythromycin polyketide synthetase should contain the sole dehydratase domain, thus generating a saturated chain at the C6-7 of erythromycin. We constructed replacement plasmids with PCR products, by using primers which had been derived from the sequences of avermectin aveAI and the erythromycin eryAII biosynthetic gene cluster. If the original dehydratase of Streptomyces avermitilis were exchanged with the corresponding erythromycin gene located on the replacement plasmid, it would be expected to result in the formation of precursors which contain alkene at C22-23, formed by the dehydratase of erythromycin module 4, and further processed by avermectin polyketide synthase. Consequently, the resulting recombinant strain JW3105, which harbors the dehydratase gene derived from erythromycin, was shown to produce only C22,23-unsaturated avermectin compounds. Our research indicates that the desired compound may be produced via polyketide gene replacement.

Pseudorecombination between Two Distinct Strains of Cucumber mosaic virus Results in Enhancement of Symptom Severity

  • Phan, Mi Sa Vo;Seo, Jang-Kyun;Choi, Hong-Soo;Lee, Su-Heon;Kim, Kook-Hyung
    • The Plant Pathology Journal
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    • v.30 no.3
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    • pp.316-322
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    • 2014
  • Recently, a Cucumber mosaic virus (CMV) strain, named as CMV-209, was isolated from Glycine soja. In this study, symptom expression of CMV-209 was analyzed in detail in Nicotiana benthamiana by comparing with that of CMV-Fny, which is a representative strain of CMV. Using infectious cDNA clones of CMV strains 209 and Fny, symptom expression of various pseudorecombinants between these two strains were examined in the early and late infection stages. In the early infection stage, the pseudorecombinants containing Fny-RNA2 induced stunting and leaf distortion on the newly emerged leaves whereas the pseudorecombinants containing 209-RNA2 caused no obvious symptoms. In the late infection stage, the pseudorecombinants containing 209-RNA1 and Fny-RNA2 induced severe leaf distortion and stunting, while CMV-209 induced mild symptom and CMV-Fny caused typical mosaic, general stunting, and leaf distortion symptoms, indicating that RNA 2 encodes a symptom determinant(s) of CMV, which is capable of enhancing symptoms. Furthermore, our results support the possibility that natural recombination between compatible viruses can result in emergence of novel viruses causing severe damages in crop fields.

Reliability evaluation of distribution systems vs. the optimal load transferring using genetic algorithms (유전 알고리즘을 이용한 최적부하절체에 의한 배전계통의 신뢰도 평가)

  • Han, Seong-Ho;Choi, Joon-Ho;Choi, Do-Hyuk;Rhee, Wook;Choi, Dai-Seub;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.862-864
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    • 1996
  • This paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic algorithm(GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transferring problem to minimize over load generated load point outage in each sub-section. This kind of the approach is one of the most difficult procedure which becomes a combination problems. A new approach using GA Was developed for this problem. We proposed a tree search algorithm which satisfied the tree constraint. GA is general purpose optimization techniques based on principles inspired from the biological evolution such as natural selection, genetic recombination and survival of the fittest Test results for the model system with 24 nodes and 29 branches are reported in the paper.

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