• Title/Summary/Keyword: Expression vectors

Search Result 396, Processing Time 0.024 seconds

Cytolytic Effects of an Adenoviral Vector Containing L-Plastin Promoter Regulated E1A in Hepatocellular Carcinoma Cells

  • Chung, In-Jae
    • Biomolecules & Therapeutics
    • /
    • v.14 no.3
    • /
    • pp.148-151
    • /
    • 2006
  • We have previously reported that 2.4 kb of L-plastin promoter (LP) could regulate the expression of adenoviral vector (AV) exogenous genes in a tumor cell specific manner. In the present study, we tested if the replication competent AdLPE1A vector results in a direct cytotoxic effect in hepatocelluar carcinoma (HCC) cells. In vitro cytotoxicity tests were carried out with replication-competent (AdLPE1A) and -incompetent (AdLPCD) LP-driven vectors. AdLPE1A is an AV in which LP was inserted 5' to the E1A and E1B genes. The AdLPCD vector contains LP and the E. coli cytosine deaminase (CD) gene in transcription unit. Exposure of cells to AdLPE1A generated a significant cytotoxic effect as compared to the control. Almost 90% of the cell had manifested the characteristic cytopatic effect on day 9 after infection of cells with 10 MOI of AdLPE1A. On the other hand, almost 35% of the cells were left when the cells had been treated with 100 MOI of AdLPCD together with 5-FC on day 9 when compared with the cells which had never been exposed neither 5-FC nor AdLPCD. These results showed that the replication competent AdLPE1A vector could kill the HepG2 cells directly by the oncolytic effect of the virus. The replication competent AV vector carrying viral E1A generated greater cytotoxic effect than the replication incompetent AV, which contains the CD prodrug activation transcription unit without E1A, in HepG2 cells.

Mass production and application of activation tagged hairy root lines for functional genomic of secondary metabolism in ginseng

  • Choi, Dong-Woog;Chung, Hwa-Jee;Ko, Suk-Min;In, Dong-Soo;Song, Ji-Sook;Woo, Sung-Sick;Liu, Jang R.
    • Journal of Plant Biotechnology
    • /
    • v.36 no.3
    • /
    • pp.294-300
    • /
    • 2009
  • Activation tagging that uses T-DNA vectors containing multimerized transcriptional enhancers from the cauliflower mosaic virus (CaMV) 35S gene is a powerful tool to determine gene function in plants. This approach has been successfully applied in screening various types of mutations and cloning the corresponding genes. We generated an activation tagged hairy root pool of ginseng (Panax ginseng C.A. Meyer) in an attempt to isolate genes involved in the biosynthetic pathway of ginsenoside (triterpene saponin), which is known as the major active ingredient of the root. Quantitative and qualitative variation of ginsenoside in activation tagged hairy root lines were profiled using LC/MS. Metabolic profiling data enabled selection of a specific hairy root line which accumulated ginsenoside at a higher level than other lines. The relative expression level of several genes of triterpene biosynthetic pathway in the selected hairy root line was determined by real time RT-PCR. Overall results suggest that the activation tagged ginseng hairy root system described in this study would be useful in isolating genes involved in a complex metabolic pathway from genetically intractable plant species by metabolic profiling.

Improved plastid transformation efficiency in Scoparia dulcis L.

  • Kota, Srinivas;Hao, Qiang;Narra, Muralikrishna;Anumula, Vaishnavi;Rao, A.V;Hu, Zanmin;Abbagani, Sadanandam
    • Journal of Plant Biotechnology
    • /
    • v.46 no.4
    • /
    • pp.323-330
    • /
    • 2019
  • The high expression level of industrial and metabolically important proteins in plants can be achieved by plastid transformation. The CaIA vector, a Capsicum-specific vector harboring aadA (spectinomycin resistance), is a selectable marker controlled by the PsbA promoter, and the terminator is flanked by the trnA and trnI regions of the inverted repeat (IR) region of the plastid. The CaIA vector can introduce foreign genes into the IR region of the plastid genome. The biolistic method was used for chloroplast transformation in Scoparia dulcis with leaf explants followed by antibiotic selection on regeneration medium. Transplastomes were successfully screened, and the transformation efficiency of 3 transgenic lines from 25 bombarded leaf explants was determined. Transplastomic lines were evaluated by PCR and Southern blotting for the confirmation of aadA insertion and its integration into the chloroplast genome. Seeds collected from transplastomes were analyzed on spectinomycin medium with wild types to determine genetic stability. The increased chloroplast transformation efficiency (3 transplastomic lines from 25 bombarded explants) would be useful for expressing therapeutically and industrially important genes in Scoparia dulcis L.

Blind Signal Subspace-Based Channel Identification for DS/CDMA DM Downlink (DS/CDMA DMB 하향 링크에서의 신호 공간에 기초한 블라인드 채널 추정)

  • Yang Wan-Chul;Lee Byung-Seub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.15 no.9
    • /
    • pp.848-855
    • /
    • 2004
  • In this paper, we propose a new channel identification technique for long code DS/CDMA DMB down link system which estimate the channel response based on the signal space vector only, unlike the most conventional subspace method relying on the orthogonal property of noise space vectors to the signal space vector. Because of this property of the proposed method, it is optimum and practical in manipulation of the covariance matrix to be analyzed. In the paper, we derive the mathematical expression necessary to clarify the proposed method and show the relevant simulation and numerical results to verify the validity of the proposed algorithm.

Exploiting Gastrointestinal Microbes for Livestock and Industrial Development - Review -

  • Singh, Birbal;Bhat, Tej K.;Singh, Bhupinder
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.4
    • /
    • pp.567-586
    • /
    • 2001
  • Gastrointestinal tract of ruminants as well as monogastric animals are colonised by a variety of microorganisms including bacteria, fungi and protozoa. Gastrointestinal ecosystem, especially the rumen is emerging as an important source for enrichment and natural selection of microbes adapted to specific conditions. It represents a virtually untapped source of novel products (e.g. enzymes, antibiotics, bacteriocins, detoxificants and aromatic compounds) for industrial and therapeutic applications. Several gastrointestinal bacteria and fungi implicated in detoxification of anti-nutritional factors (ANFs) can be modified and manipulated into promising system for detoxifying feed stuffs and enhancing fibre fermentation both naturally by adaptation or through genetic engineering techniques. Intestinal lactobacilli, bifidobacteria and butyrivibrios are being thoroughly investigated and widely recommended as probiotics. Restriction endonucleases and native plasmids, as stable vectors and efficient DNA delivery systems of ruminal and intestinal bacteria, are increasingly recognised as promising tools for genetic manipulation and development of industrially useful recombinant microbes. Enzymes can improve the nutrient availability from feed stuffs, lower feed costs and reduce release of wastes into the environment. Characterization of genes encoding a variety of commercially important enzymes such as cellulases, xylanases, $\beta$-glucanases, pectinases, amylases and phytases will foster the development of more efficacious and viable enzyme supplements and enzyme expression systems for enhancing livestock production.

Hepatitis C Virus Core Protein Is Efficiently Released into the Culture Medium in Insect Cells

  • Choi, Soo-Ho;Kim, So-Yeon;Park, Kyu-Jin;Kim, Yeon-Joo;Hwang, Soon-Bong
    • BMB Reports
    • /
    • v.37 no.6
    • /
    • pp.735-740
    • /
    • 2004
  • Hepatitis C virus (HCV) is a causal agent of the chronic liver infection. To understand HCV morphogenesis, we studied the assembly of HCV structural proteins in insect cells. We constructed recombinant baculovirus expression vectors consisting of either HCV core alone, core-E1, or core-E1-E2. These structural proteins were expressed in insect cells and were examined to assemble into particles. Neither core-E1 nor core-E1-E2 was capable of assembling into virus-like particles (VLPs). It was surprising that the core protein alone was assembled into core-like particles. These particles were released into the culture medium as early as 2 days after infection. In our system, HCV structural proteins including envelope proteins did not assemble into VLPs. Instead, the core protein itself has the intrinsic capacity to assemble into amorphous core-like particles. Furthermore, released core particles were associated with HCV RNA, indicating that core proteins were assembled into nucleocapsids. These results suggest that HCV may utilize a unique core release mechanism to evade the hosts defense mechanism, thus contributing to the persistence of HCV infection.

Characterization of Constitutively Activating Eel Follicle-Stimulating Hormone Receptor

  • Kim, Jeong-Soo;Byambaragchaa, Munkhzaya;Min, Kwan-Sik
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.34 no.4
    • /
    • pp.267-271
    • /
    • 2019
  • This study aimed to investigate the function of the constitutively activating mutation D540G on eel FSHR activity by in vitro functional studies. Site-directed mutagenesis was carried out to generate the D-to-G mutation at position 540 of the pcDNA3-eel FSHR construct. Vectors expressing either wild type or mutant receptor were transfected into Chinese hamster ovary (CHO-K1) cells. The functional characteristics of both the wild type and mutant receptors were analyzed by a cAMP assay. cAMP accumulation was highly increased in cells transfected with the D540G mutant receptor in a dose-dependent manner. Of note, basal cAMP levels were remarkably increased (~13.1-fold) with expression of this mutant when compared to wild type receptor. These findings suggest that the D540G mutation in the eel FSHR may contribute to ovulation during eel sex maturation as well as play a pivotal role in inducing FSHR activity.

A study on local facial features using LDP (LDP를 이용한 지역적 얼굴 특징 표현 방법에 관한 연구)

  • Cho, Young Tak;Jung, Woong Kyung;Ahn, Yong Hak;Chae, Ok Sam
    • Convergence Security Journal
    • /
    • v.14 no.5
    • /
    • pp.49-56
    • /
    • 2014
  • In this paper, we proposed a method for representing local facial features based on LDP (Local Directional Pattern). To represent both PFF (Permanent Facial Features) and TFF (Transient Facial Features) effectively, the proposed method configure local facial feature vectors based on overlapped blocks for each facial feature in the forms of various size and shape. There are three advantages - it take advantages of geometric feature based method; it shows robustness about detection error using movement characteristics of each facial feature; and it shows reduced sampling error because maintain spatial information caused by block size variability. Proposed method shows better classification accuracy and reduced amount of calculation than existing methods.

Specific Isoforms of Protein Kinase G Downregulate the Transcription of Cyclin D1 in NIH3T3

  • Lim, Seon Young;Soh, Jae-Won
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.4
    • /
    • pp.1165-1169
    • /
    • 2013
  • To elucidate the role of PKG isoforms in transcriptional control of cyclin D1, we employed a series of expression vectors of PKG $1{\alpha}$ and PKG $1{\beta}$ which encode HA-tagged wild type and constitutively active (SD and ${\Delta}N$) mutants. Our present study demonstrates that both the constitutively active mutants of PKG $1{\beta}$ downregulate the transcription of cyclin D1 when transiently transfected in NIH3T3 cells, whereas PKG $1{\alpha}$ mutants show weak inhibition. We further studied the transcriptional regulators of cyclin D1, such as, c-fos, NF-${\kappa}B$, and CRE by using the luciferase reporter assay. Constitutively active mutants of PKG $1{\beta}$ showed marked transcriptional downregulation of c-fos in NIH3T3 cells, whereas PKG $1{\alpha}$ downregulated c-fos to a lesser extent. We also found that the constitutively active mutants of PKG negatively regulated the activation of NF-${\kappa}B$ and CRE, suggesting their involvement in the regulation of cyclin D1.

Purification and NMR Studies of RNA Polymerase II C-Terminal Domain Phosphatase 1 Containing Ubiquitin Like Domain

  • Ko, Sung-Geon;Lee, Young-Min;Yoon, Jong-Bok;Lee, Weon-Tae
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.5
    • /
    • pp.1039-1042
    • /
    • 2009
  • RNA polymerase II C-terminal domain phosphatase 1 containing ubiquitin like domain (UBLCP1) has been identified as a regulatory molecule of RNA polymerase II. UBLCP1 consists of ubiquitin like domain (UBL) and phosphatase domain homologous with UDP and CTD phosphatase. UBLCP1 was cloned into the E.coli expression vectors, pET32a and pGEX 4T-1 with TEV protease cleavage site and purified using both affinity and gel-filtration chromatography. Domains of UBLCP1 protein were successfully purified as 7 mg/500 mL (UBLCP1, 36.78 KDa), 32 mg/500 mL (UBL, 9 KDa) and 8 mg/500 mL (phosphatase domain, 25 KDa) yielded in LB medium, respectively. Isotope-labeled samples including triple-labeled ($^2H/^{15}N/^{13}C$) UBLCP1 were also prepared for hetero-nuclear NMR experiments. $^{15}N-^{1}H$ 2D-HSQC spectra of UBLCP1 suggest that both UBL and phosphatase domain are properly folded and structurally independent each other. These data will promise us further structural investigation of UBLCP1 by NMR spectroscopy and/or X-ray crystallography.