• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.115-118
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• 2000

Recombinant plasmids harboring a heterologous gene coding for the enhanced green fluorescent protein (EGFP) were transfected and expressed in Drosophila melanogaster S2 cells. A stable transformation of polyclonal cell populations expressing EGFP were isolated after 4 weeks of selection with hygromycin B. The recombinant EFGP expressed in transformed S2 cells consisted of a molecular weight of 27 kDa. EGFP expression was also confirmed by fluorometric measurement. The maximum EGFP concentration was about 9.3 mg/I. The present findings demonstrate not only the successful stable expression of EGFP in Drosophuila was about 9.3 mgI. The present findings demonstrate not only the successful stable expression of EGFP in Drosophila S2 cells, but also the use of EGFP as a reporter to analyze gene expression, with its potential of a Drosophila cell expression system for recombinant protein production being an alternative to a baculovirus-insect cell expression system.

• Animal cells and systems
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• v.2 no.1
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• pp.113-116
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• 1998

A cDNA clone coding for ribosomal protein 46 (rp46) which is a component of 60S ribosomal large subunit has been identified from Drosophila melanogaster. A cDNA clone encoding S. cerevisiae rp46 was used as a probe to screen a Drosophila larvae cDNA library. The DNA sequence analysis revealed that the cDNA coding for Drosophils rp46 contains a complete reading frame of 153 nucleotides coding for 51 amino acids. The deduced amino acid sequence showed 71-75% homology with those of other eukaryotic organisms. Northern blot analysis showed that about 1-kb rp46 transcripts are abundant throughout fly development. Whole mount embryonic mRNA in situ hybridization also showed no preferential distribution of the transcripts to any specific region. The chromosomal in situ hybridization revealed that the identified gene is localized at position 60C on the right arm of the second polytene chromosome with a possibility of single copy.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.149-150
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• 2003

The purpose of this experiment is to optimize the yield of the recombinant Cox2 from the stably transformed Drosophila melanogaster S2 cells, using dimethylsulfoxide and sodium butyrale. Materials and Methods : Materials - Cell line : Drosophila melanogaster Schneider 2 (S2) cells - vector pMT/BiP/V5-His and pCoHygro (Invitrogen) (omitted)

• Applied Biological Chemistry
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• v.44 no.4
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• pp.211-214
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• 2001

Utilizing the foreign gene expression system of Drosophila melanogaster Schneider line 2(S2) cell, the degree of transient protein and mRNA expression was examined with different terminators. In the case of transient expression, the expression level of green fluorescent protein(GFP) was the highest when the transfection agent was eliminated and then cultivated for 36 to 48 hr. The terminators(SV40 p(A), SV40 small T-antigen and human gastrin 3'UTR) of the expression vector system were each cloned with endostatin; thereafter, the expression levels of the endostatin and its mRNA were compared. When the expression levels of endostatin were compared 36 hr after transfection, the SV40 p(A) terminator showed the highest expression level of endostatin and its mRNA.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.147-148
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• 2003

The purpose of this experiment is to confirm whether the recombinant tumstatin revealed from the stably transformed Drosophila melanogaster S2 cells has in vitro capacity. Materials and Methods : Materials - Cell line : Drosophila melanogaster Schneider 2 (S2) cells - vector pMT/BiP/V5-His and pCoHygro (Invitrogen) (omitted)

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.40-40
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• 2003

Recombinant plasmids harboring heterologous genes coding enhanced green fluorescent protein (EGFP) and erythropoietin (EPO) were transfected and expressed in Drosophila melanogaster S2 cells. Stably transformed cell populations expressing EGFP or monkey EPO were isolated after 4 weeks of selection with hygromycin B. (omitted)

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.563-568
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• 2002

Stably transformed Drosophila melanogaster 52 cells producing recombinant VP7 were obtained, and recombinant VP7 expression was confirmed by Western blot analysis. The molecular weight of recombinant VP7 expressed in 52 cells was approximately 35.5 kDa, and 75% of the total VP7 produced was present in the medium. Recombinant VP7 contained N-linked glycosylated oligosaccharides. Aprotinin, leupeptin, and polyvinylpyrrolidone did not have any noticeable effect on recombinant VP7 production; however, DMSO and sodium butyrate increased its production by 120% and 60%, respectively.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.40-45
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• 2006

The baculovirus-insect Drosophila melanogaster S2 cell system combines advantages of conventional baculovirus system and non-lytic S2 cell system because baculoviruses can infect non-permissive cells such as mammalian and Drosophila S2 cells but cannot replicate themselves inside the cells. In the present work, we investigated effects of infection conditions on production of green fluorescent protein (GFP) as a target protein using this baculovirus-S2 cell system. Even though higher MOI and longer baculovirus contact time showed better GFP expression yield during the shorter period, overall protein yield could be lower during the longer period due to the relatively higher cell detachment and lysis (lower cell viability). In addition, maintaining high MOI will be not practical for large-scale cell culture. Therefore, instead of maintaining high MOI, we found that high initial cell number and concentrated (10X) baculovirus volume can confer comparable protein expression even under the moderate MOI condition. Also, we found that the post-infection time that is connected to state of cells after infection was an important factor for production yield.

• Applied Microscopy
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• v.39 no.2
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• pp.185-189
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• 2009

Studies about the structure of Drosophila melanogaster retinal cell using electron microscopy have been carried out in details since 1960s. However, these results can have limitations in functional research because of two-dimensional structure. In this study, the adult retina of Drosophila melanogaster was investigated by employing high pressure freezing method, serial sections, high voltage electron microscopy, and 3-dimensional reconstruction method. From there results, mitochondria, microtubules, and nuclei were reconstructed as 3-dimensional structure using IMOD program. The 3D structure of these organelles showed that mitochondira mainly located in distal region near lens, and microtubule mainly located in distal and basal region. The 3D reconstruction of these organelles can be used for a critical evaluation in the dynamic change of cellular organelles caused by functional abnormality like retinal degeneration.

• Molecules and Cells
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• v.44 no.1
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• pp.13-25
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• 2021

Apoptosis and compensatory proliferation, two intertwined cellular processes essential for both development and adult homeostasis, are often initiated by the mis-regulation of centrosomal proteins, damaged DNA, and defects in mitosis. Fly Anastral spindle 3 (Ana3) is a member of the pericentriolar matrix proteins and known as a key component of centriolar cohesion and basal body formation. We report here that ana3m19 is a suppressor of lethality induced by the overexpression of Sol narae (Sona), a metalloprotease in a disintegrin and metalloprotease with thrombospondin motif (ADAMTS) family. ana3m19 has a nonsense mutation that truncates the highly conserved carboxyl terminal region containing multiple Armadillo repeats. Lethality induced by Sona overexpression was completely rescued by knockdown of Ana3, and the small and malformed wing and hinge phenotype induced by the knockdown of Ana3 was also normalized by Sona overexpression, establishing a mutually positive genetic interaction between ana3 and sona. p35 inhibited apoptosis and rescued the small wing and hinge phenotype induced by knockdown of ana3. Furthermore, overexpression of Ana3 increased the survival rate of irradiated flies and reduced the number of dying cells, demonstrating that Ana3 actively promotes cell survival. Knockdown of Ana3 decreased the levels of both intra- and extracellular Sona in wing discs, while overexpression of Ana3 in S2 cells dramatically increased the levels of both cytoplasmic and exosomal Sona due to the stabilization of Sona in the lysosomal degradation pathway. We propose that one of the main functions of Ana3 is to stabilize Sona for cell survival and proliferation.