• Title/Summary/Keyword: expression system

Search Result 4,441, Processing Time 0.035 seconds

Expression Pattern of Early Growth Response Gene 1 during Olive Flounder (Paralichthys olivaceus) Embryonic Development

  • Yang, Hyun;Lee, Jeong-Ho;Noh, Jae Koo;Kim, Hyun Chul;Park, Choul-Ji;Park, Jong-Won;Kim, Kyung-Kil
    • Development and Reproduction
    • /
    • v.18 no.4
    • /
    • pp.233-240
    • /
    • 2014
  • The early growth response protein 1 (Egr-1) is a widely reported zinc finger protein and a well known transcription factor encoded by the Egr-1 gene, which plays key roles in many aspects of vertebrate embryogenesis and in adult vertebrates. The Egr-1 expression is important in the formation of the gill vascular system in flounders, which develops during the post-hatching phase and is essential for survival during the juvenile period. However, the complete details of Egr-1 expression during embryo development in olive flounder are not available. We assessed the expression patterns of Egr-1 during the early development of olive flounders by using reverse transcription polymerase chain reaction (RT-PCR) analysis. Microscopic observations showed that gill filament formation corresponded with the Egr-1 expression. Thus, we showed that Egr-1 plays a vital role in angiogenesis in the gill filaments during embryogenesis. Further, Egr-1 expression was found to be strong at 5 days after hatching (DAH), in the development of the gill vascular system, and this strong expression level was maintained throughout all the development stages. Our findings have important implications with respect to the biological role of Egr-1 and evolution of the first respiratory blood vessels in the gills of olive flounder. Further studies are required to elucidate the Egr-1-mediated stress response and to decipher the functional role of Egr-1 in developmental stages.

Trap identification of the constitutive promoter-like sequences from the bacterial fish pathogen, as exemplified by Edwardsiella tarda

  • Lee, Sang-Yoon;Kim, Ki-Hong;Kim, Dong-Soo;Nam, Yoon-Kwon
    • Journal of fish pathology
    • /
    • v.24 no.3
    • /
    • pp.297-305
    • /
    • 2011
  • A trap identification system for isolating functional sequences to allow the constitutive expression of foreign protein from Edwardsiella tarda was developed. Using the green fluorescent protein (GFP) reporter-based trap system, various functional sequences to drive heterologous expression of the GFP were selectable in Escherichia coli host. However from the bioinformatic sequence analysis, all the segments predicted as regulatory regions were not native promoters actually existing upstream of endogenous E. tarda genes. Instead, a number of non-authentic sequences, possibly resulted from the random shuffling and/or intermolecular ligation were also proven to be able to display a potent GFP expression in the recombinant E. coli. Further analysis with selected clones showed that both authentic and non-authentic sequences could function in as a constitutive promoter, leading quite a consistent and stable GFP expression after repetitive subcultures. Microscopic examination also confirmed the uniform pattern of GFP expression in every host bacterium. Semi-quantitative assay of GFP showed that there was no clear relationship between expression levels and organizational features of the promoters trapped. Functional promoter-like elements achieved in the present study could be a good starting material for multivalent genetic engineering of E. tarda in order to produce recombinant vaccines in a cost-effective fashion.

Effect of Galactose and Dextrose on Human Lipocortin I Expression in Recombinant Saccharomyces cerevisiae Carrying Galactose-Regulated Expression System

  • Nam, Soo-Wan;Seo, Dong-Jin;Rhee, Sang-Ki;Park, Young-Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • v.3 no.3
    • /
    • pp.168-173
    • /
    • 1993
  • The expression kinetics of human lipocortin I (LCI), a potential anti-inflammatory agent, was studied in the shake-flask and fermenter cultures of Saccharomyces cerevisiae carrying a galactose-inducible expression system. The cell growth, expression level of LCI, and the plasmid stability were investigted under various galactose induction conditions. The expression of LCI was repressed by the presence of a very small amount of dextrose in the culture medium, but it was induced by galactose after dextrose became completely depleted. The optimal ratio of dextrose to galactose for lipocortin I production was found to be 1.0 (10 g/l dextrose and 10 g/l galactose). With optimal D/G ratio of 1.0 and the addition of galactose prior to dextrose depletion, LCI of about 100~130 mg/l was produced. LCI at a concentration of 174 mg/l was porduced in the fed-batch culture, which was nearly a twice as much of that produced in the batch culture. The plasmid stability was very high in all culture cases, and thus was considered to be not an important parameter in the expression of LCI.

  • PDF

Analysis of C. elegans VIG-1 Expression

  • Shin, Kyoung-Hwa;Choi, Boram;Park, Yang-Seo;Cho, Nam Jeong
    • Molecules and Cells
    • /
    • v.26 no.6
    • /
    • pp.554-557
    • /
    • 2008
  • Double-stranded RNA (dsRNA) induces gene silencing in a sequence-specific manner by a process known as RNA interference (RNAi). The RNA-induced silencing complex (RISC) is a multi-subunit ribonucleoprotein complex that plays a key role in RNAi. VIG (Vasa intronic gene) has been identified as a component of Drosophila RISC; however, the role VIG plays in regulating RNAi is poorly understood. Here, we examined the spatial and temporal expression patterns of VIG-1, the C. elegans ortholog of Drosophila VIG, using a vig-1::gfp fusion construct. This construct contains the 908-bp region immediately upstream of vig-1 gene translation initiation site. Analysis by confocal microscopy demonstrated GFP-VIG-1 expression in a number of tissues including the pharynx, body wall muscle, hypodermis, intestine, reproductive system, and nervous system at the larval and adult stages. Furthermore, western blot analysis showed that VIG-1 is present in each developmental stage examined. To investigate regulatory sequences for vig-1 gene expression, we generated constructs containing deletions in the upstream region. It was determined that the GFP expression pattern of a deletion construct (${\Delta}-908$ to -597) was generally similar to that of the non-deletion construct. In contrast, removal of a larger segment (${\Delta}-908$ to -191) resulted in the loss of GFP expression in most cell types. Collectively, these results indicate that the 406-bp upstream region (-596 to -191) contains essential regulatory sequences required for VIG-1 expression.

Mass expression of Apx I and Apx II of Actinobacillus pleuropneumoniae in Escherichia coli (대장균에서 흉막폐렴균 독소 Apx I과 Apx II의 대량발현)

  • Kim, Tae-Jung;Lee, Bong-Joo;Lee, Jae-Il
    • Korean Journal of Veterinary Research
    • /
    • v.45 no.2
    • /
    • pp.185-189
    • /
    • 2005
  • Actinobacillus pleuropneumoniae is the causative agent of a porcine contagious pleuropneumonia. Among several virulence factors including exotoxin (Apx toxins), LPS, transferrin-binding proteins, OMPs, and some proteases, Apx toxins have been major targets for the protection study. In this study, cloning and expression of A. pleuropneumoniae Apx I and Apx II toxin, which are produced by all highly virulent strains, were performed by Escherichia coli expression system. Genes coding Apx I and II toxin were amplified from the A. pleuropneumoniae serotype 5 genomic DNA using polymerase chain reaction and cloned to a prokaryotic expression vector, pRSET. Expression of the Apx I and Apx II coding sequences in E. coli resulted in the formation of insoluble inclusion bodies purified according to a denaturing purification protocol, which employs the use of guanidium. Recombinant proteins were purified using $Ni^{2+}$-charged resin affinity purification. This expression and purification system made it possible to produce Apx I and Apx II in large amounts for further immunologic studies.

Evaluation of a New Episomal Vector Based on the GAP Promoter for Structural Genomics in Pichia pastoris

  • Hong In-Pyo;Anderson Stephen;Choi Shin-Geon
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.9
    • /
    • pp.1362-1368
    • /
    • 2006
  • A new constitutive episomal expression vector, pGAPZ-E, was constructed and used for initial screening of eukaryotic target gene expression in Pichia pastoris. Two reporter genes such as beta-galactosidase gene and GFPuv gene were overexpressed in P. pastoris. The expression level of the episomal pGAPZ-E strain was higher than that of the integrated form when the beta-galactosidase gene was used as the reporter gene in P. pastoris X33. The avoiding of both the integration procedure and an induction step simplified the overall screening process for eukaryotic target gene expression in P. pastoris. Nine human protein targets from the Core 50, family of Northeast Structural Genomics Consortium (http://www.nesg.org), which were intractable when expressed in E. coli, were subjected to rapid screening for soluble expression in P. pastoris. HR547, HR919, and HR1697 human proteins, which had previously been found to express poorly or to be insoluble in E. coli, expressed in soluble form in P. pastoris. Therefore, the new episomal GAP promoter vector provides a convenient and alternative system for high-throughput screening of eukaryotic protein expression in P. pastoris.

A study on the effect factor of architectural material expression (재료의 물성 표현에 영향을 주는 요인 연구)

  • Kim, So-Hee
    • Korean Institute of Interior Design Journal
    • /
    • v.15 no.6 s.59
    • /
    • pp.60-67
    • /
    • 2006
  • In modem days when architectural materials have grave impacts on overall design expression, materials for architecture, especially finishing materials have become the most essential elements for the design expression, as architectural space and form have been. When it comes to the architectural materials, they can be conceived by visual and tactile sensory system and perceptional system which based on memory and experience. This study confirms how materials bring into effect on architecture in the sense of its design. The main subject of this analysis is expression method of architectural finishing materials. Also, this study finds out the relationship between finishing materials and the images of materials by analyzing the effect factor of architectural material expression with the perspectives of materials, formal and environments and by examining roles of the architectural materials in design. The material factor, in the expression of materiality, is how to make tectonic space and to vary the surface of building as finishing material design. The formal factor is related to set up the new direction in the architectural form and to create the dynamic and informal space. And the social and cultural environment as the effect factor gives new situation and context to architectural material expression. This principle enables us to use architectural materials as one of the important elements which express the whole characteristics of the area.

The Chronic and Unpredictable Stress Suppressed Kisspeptin Expression during Ovarian Cycle in Mice

  • Kim, Seung-Joon
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.34 no.1
    • /
    • pp.40-49
    • /
    • 2019
  • Chronic and unpredictable stress can disrupt the female reproductive system by suppression for secretion of gonadotrophin-releasing hormone (GnRH) and gonadotrophin, resulted in ovarian malfunction and infertility. In the recent days, kisspeptin has been highly highlighted as a hypothalamic peptide which directly stimulates synthesis and release for GnRH. However, in spite of the key role of kisspeptin in the female reproductive system, little information is still available on the changes of its expression during ovarian cycle under stressed condition. Therefore, we induced chronic and unpredictable stress series to the female mice to analyze kisspeptin expression in the brain and ovary. Stressed mice exhibited changes of behavior and body weight gain during the stress assessment, which suggested that the present stress model in mice was successfully established. In the brain level, kisspeptin expression was attenuated than control. In the ovary level, the stressed mice displayed irregularly shrunk oocytes with broken zona pellucida throughout the follicle stages, pyknotic granulosa cells, decreased number of developing follicles and increased number of atretic follicles than the control. In case of kisspeptin expression in the whole ovary tissue, the expression level was decreased in the stressed mice. In detail, the less intensity of kisspeptin expression in the antral follicles phase was observed in the stressed mice than control mice, indicating that local function of kisspeptin during ovary cycle is highly associated with development of ovarian follicles. We expect that the present study has important implications for the fields of reproductive biology.

Investigation of Agrobacterium-mediated Transient dsRNA Expression in Tobacco

  • Choi, Wonkyun;Lim, HyeSong;Seo, Hankyu;Kim, Dong Wook
    • Korean Journal of Ecology and Environment
    • /
    • v.52 no.4
    • /
    • pp.394-402
    • /
    • 2019
  • The Agrobacterium tumefaciens mediated gene transfer is widely used to generate genetic transformation of plants and transient assay of temporal exogenous gene expression. Syringe infiltration system into tobacco (Nicotiana benthamiana) leaves is a powerful tool for transient expression of target protein to study protein localization, protein-protein binding and protein production. However, the protocol and technical information of transient gene expression, especially double strand RNA (dsRNA), in tobacco using Agrobacterium is not well known. Recently, dsRNA is crucial for insecticidal effect on destructive agronomic pest such as Corn rootworm. In this study, we investigated the factor influencing the dsRNA expression efficiency of syringe agro-infiltration in tobacco. To search the best combination for dsRNA transient expression in tobacco, applied two Agrobacterium cell lines and three plant vector systems. The efficiency of dsRNA expression has estimated by real-time PCR and digital PCR. As a result, pHellsgate12 vector constructs showed the most effective accumulation of dsRNA in the cell. These results indicated that the efficiency of dsRNA expression was depending on the kind of vector rather than Agrobacterium cells. In summary, the optimized combination of transient dsRNA expression system in tobacco might be useful to in vivo dsRNA expression for functional study and risk assessment of dsRNA.

Effects of exercise on myokine gene expression in horse skeletal muscles

  • Lee, Hyo Gun;Choi, Jae-Young;Park, Jung-Woong;Park, Tae Sub;Song, Ki-Duk;Shin, Donghyun;Cho, Byung-Wook
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.3
    • /
    • pp.350-356
    • /
    • 2019
  • Objective: To examine the regulatory effects of exercise on myokine expression in horse skeletal muscle cells, we compared the expression of several myokine genes (interleukin 6 [IL-6], IL-8, chemokine [C-X-C motif] ligand 2 [CXCL2], and chemokine [C-C motif] ligand 4 [CCL4]) after a single bout of exercise in horses. Furthermore, to establish in vitro systems for the validation of exercise effects, we cultured horse skeletal muscle cells and confirmed the expression of these genes after treatment with hydrogen peroxide. Methods: The mRNA expression of IL-6, IL-8, CXCL2, and CCL4 after exercise in skeletal muscle tissue was confirmed using quantitative-reverse transcriptase polymerase chain reactions (qRT-PCR). We then extracted horse muscle cells from the skeletal muscle tissue of a neonatal Thoroughbred. Myokine expression after hydrogen peroxide treatments was confirmed using qRT-PCR in horse skeletal muscle cells. Results: IL-6, IL-8, CXCL2, and CCL4 expression in Thoroughbred and Jeju horse skeletal muscles significantly increased after exercise. We stably maintained horse skeletal muscle cells in culture and confirmed the expression of the myogenic marker, myoblast determination protein (MyoD). Moreover, myokine expression was validated using hydrogen peroxide ($H_2O_2$)-treated horse skeletal muscle cells. The patterns of myokine expression in muscle cells were found to be similar to those observed in skeletal muscle tissue. Conclusion: We confirmed that several myokines involved in inflammation were induced by exercise in horse skeletal muscle tissue. In addition, we successfully cultured horse skeletal muscle cells and established an in vitro system to validate associated gene expression and function. This study will provide a valuable system for studying the function of exercise-related genes in the future.