• Title/Summary/Keyword: transcriptional level

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Molocular Cloning and Sequence Analysis of the Immediate Early Viral Gene, IE1, from Bombyx mori Nuclear Polyhedrosis Virus K1

  • Park, Hye-Jin;Lee, Kwang-Sik;Je, Yeon-Ho;Sohn, Hung-Dae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • v.3 no.1
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    • pp.43-49
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    • 2001
  • We have cloned and characterized an immediate early-1 gene, iel, which is activated immediately upon entrance of the viral genome into the cell nucleus, from Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. This gene encodes a protein 584 amino acids with a predicted molecular weight of 67 kDa. The promoter and coding regions of BmNPV-K1 ie1 showed high homology with Autographa californica nuclear polyhedrosis virus and BmNPV T3 strain. The BmNPV-K1 ie1 was different from amino acid sequence at 4 positions in BmNPV T3. The location of ie1 gene in the BmNPV-K1 genome was confirmed by Southern blot analysis and its expression patterns at the transcriptional level in the infected cells were confirmed by Nerthern hybridization analysis.

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Isolation and Characterization of Paraquat-inducible Promoters from Escherichia coli

  • Lee, Joon-Hee;Roe, Jung-Hye
    • Journal of Microbiology
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    • v.35 no.4
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    • pp.277-283
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    • 1997
  • Promoters inducible by paraquat, a superocide-generating agent, were isolated from Escherichia coli using a promoter-probing plasmid pRS415 with promoterless lacA gene. Twenty one promoters induced by paraquat were selected and further characterized. From sequence analysis, thirteen of the promoters were mapped to their specific loci on the Escherichia coli chromosome. Several promoters were mapped to the upstream of known genes such as usgl, katG, and mglB, whose relationships with superoxide response have not been previously reported. Other promoters were mapped to the upstream region of unknown open reading frames. Downstream of HC 96 promoter are uncharacterized ORFs whose sequences are homologous to ABC-transporter subunits. Downstream of HC84 promoter is an ORF encoding a transcriptional regulator-like protein, which contains a LysR family-specific HTH (helix-turn-helix) DNA bindign motif. We investigated whether these promoters belong to the soxRS regulon. All promoters except HC96 were found to belong to the soxRS regulon. The HC96 promoter was significantly induced by paraquat in the soxRS deletion mutant strain. The basal transcription level of three promoters (HE43, HC71, HD94) significantly increased at the stationary phase, implying that they are regulated by RpoS. However, paraquat inducibility of all promoters disappeared in the stationary phase, suggesting that SoxRS regulatory system is active only in rapidly growing cells.

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RTP1, a Rat Homologue of Adenovirus ElA-associated Protein BS69, Interacts with DNA Topoisomerase II

  • Oh, Misook;Rha, Geun-Bae;Yoon, Jeong-Ho;Sunwoo, Yang-Il;Hong, Seung-Hwan;Park, Sang-Dai
    • Animal cells and systems
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    • v.6 no.3
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    • pp.277-282
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    • 2002
  • Topoisomearse II is an essential enzyme in all organisms with several independent roles in DNA metabolism. Recently, it has been demonstrated that the C-terminal region of topoisomerases II is associated with hetero-logous protein-protein interactions in human and yeast. In this study, we identified that RTP1, a rat homologue of EIA binding protein BS69, is another topoisomerae II interacting protein by yeast two-hybrid screening. RTP1 has an E1A-binding domain and a MYND motif, which are known to be required for transcriptional regulation by binding to other proteins and interaction with the leucine zipper motif of topoisomerase II. The physical interaction between RTP1 and topoisomerase ll$\alpha$ was examined by GST pull-down assay in vitro. The expression level of RTP1 peaks in S phase as that of topoisomerase ll$\alpha$. These results suggest that the interaction between topoisomerase ll$\alpha$ and RTP1 might play an important role in regulating the transcription of genes involved in DNA metabolism in higher eukaryotes.

Effects of pH Shock on the Secretion System in Streptomyces coelicolor A3(2)

  • Kim, Yoon-Jung;Song, Jae-Yang;Hong, Soon-Kwang;Smith, Colin P.;Chang, Yong-Keun
    • Journal of Microbiology and Biotechnology
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    • v.18 no.4
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    • pp.658-662
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    • 2008
  • Effects of pH shock on the secretion system of S. coelicolor A3(2) have been investigated at a transcriptional level by using DNA microarrays. Actinorhodin secretion was observed to be highly enhanced when an acidic-pH shock was applied to surface grown cultures of S. coelicolor A3(2). In this culture, a gene of actVA-orf1 encoding a putative efflux pump or transporter protein for actinorhodin was strongly upregulated. A major number of efflux pumps for other metabolites and a major number of secretion proteins for protein secretion were also observed to be upregulated with pH shock. The secretion of actinorhodin was observed to be remarkably enhanced in liquid culture as well.

DNA Microarray Analysis of Gene Expression Profiles in Aging process of Mouse Brain

  • Lee Mi-Suk;Heo Jee-In;Kim Jae-Bong;Park Jae-Bong;Lee Jae-Yang;Han Jeong-A.;Kim Jong-Il
    • Genomics & Informatics
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    • v.4 no.1
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    • pp.23-32
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    • 2006
  • In order to investigate the molecular basis of the aging process in brain, we have employed high-density oligonucleotide microarrays providing data on 10,108 gene clusters to define transcriptional patterns in three brain regions, cerebral cortex, cerebellum, and hippocampus. Comparison of the expression patterns between young (6-week-old) and aged (17-month-old) C57BL/6 male micerevealed that about ten percent (1098) of the genes showed a significant change in the expression level in at least one of the three tissues. Among them, 23 genes were upregulated and 62 genes were downregulated in all three tissues of the old mice. The number of genes upregulated exclusively in hippocampus (337) was much larger compared to other tissues. Gene ontology-based analysis showed the genes related with signal transduction or molecular transports are more likely to be upregulated than downregulated in the aging process of hippocampus. These data may provide some useful means for elucidating the molecular aspect of aging in hippocampus and other regions in brain.

MicroRNA Target Recognition: Insights from Transcriptome-Wide Non-Canonical Interactions

  • Seok, Heeyoung;Ham, Juyoung;Jang, Eun-Sook;Chi, Sung Wook
    • Molecules and Cells
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    • v.39 no.5
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    • pp.375-381
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    • 2016
  • MicroRNAs (miRNAs) are small non-coding RNAs (~22 nucleotides) regulating gene expression at the post-transcriptional level. By directing the RNA-induced silencing complex (RISC) to bind specific target mRNAs, miRNA can repress target genes and affect various biological phenotypes. Functional miRNA target recognition is known to majorly attribute specificity to consecutive pairing with seed region (position 2-8) of miRNA. Recent advances in a transcriptome-wide method of mapping miRNA binding sites (Ago HITS-CLIP) elucidated that a large portion of miRNA-target interactions in vivo are mediated not only through the canonical "seed sites" but also via non-canonical sites (~15-80%), setting the stage to expand and determine their properties. Here we focus on recent findings from transcriptome-wide non-canonical miRNA-target interactions, specifically regarding "nucleation bulges" and "seed-like motifs". We also discuss insights from Ago HITS-CLIP data alongside structural and biochemical studies, which highlight putative mechanisms of miRNA target recognition, and the biological significance of these non-canonical sites mediating marginal repression.

Atractylochromene Is a Repressor of Wnt/β-Catenin Signaling in Colon Cancer Cells

  • Shim, Ah-Ram;Dong, Guang-Zhi;Lee, Hwa Jin;Ryu, Jae-Ha
    • Biomolecules & Therapeutics
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    • v.23 no.1
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    • pp.26-30
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    • 2015
  • Wnt/${\beta}$-catenin signaling pathway was mutated in about 90% of the sporadic and hereditary colorectal cancers. The abnormally activated ${\beta}$-catenin increases the cancer cell proliferation, differentiation and metastasis through increasing the expression of its oncogenic target genes. In this study, we identified an inhibitor of ${\beta}$-catenin dependent Wnt pathway from rhizomes of Atractylodes macrocephala Koidzumi (Compositae). The active compound was purified by activity-guided purification and the structure was identified as 2,8-dimethyl-6-hydroxy-2-(4-methyl-3-pentenyl)-2H-chromene (atractylochromene, AC). AC suppressed b-catenin/Tcell factor transcriptional activity of HEK-293 reporter cells when they were stimulated by Wnt3a or inhibitor of glycogen synthase kinase-$3{\beta}$. AC down-regulated the nuclear level of ${\beta}$-catenin through the suppression of galectin-3 mediated nuclear translocation of ${\beta}$-catenin in SW-480 colon cancer cells. Furthermore, AC inhibits proliferation of colon cancer cell. Taken together, AC from A. macrocephala might be a potential chemotherapeutic agent for the prevention and treatment of human colon cancer.

Identification of Differentially Expressed Genes in the Longissimus Dorsi Muscle Tissue between Duroc and Erhualian Pigs by mRNA Differential Display

  • Pan, P.W.;Zhao, S.H.;Yu, M.;Liu, B.;Xiong, T.A.;Li, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1066-1070
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    • 2003
  • In order to identify differentially expressed mRNAs (which represent possible candidates for significant phenotypic variances of muscle growth, meat quality between introduced European and Chinese indigenous pigs) in the longissimus dorsi muscle tissue between adult Duroc and Erhualian pigs, mRNA differential display was performed. Five 3' anchor primers in combination with 20 different 5' arbitrary primers (100 primer sets) were used and nearly 5,000 cDNA bands were examined, among which 10 differential display cDNAs were obtained, cloned and sequenced. Six of the 10 cDNAs showed similarity to identified genes from GenBank and the other 4 had no matches in GenBank. Differential expression was tested by Northern blot hybridization and could be confirmed for 2 cDNAs. The method used in this study provides a useful molecular tool to investigate genetic variation that occurs at the transcriptional level between different breeds.

Differential Expression of Cytochrome P450 Genes Regulate the Level of Adipose Arachidonic Acid in Sus Scrofa

  • Choi, Kyung-Mi;Moon, Jin-Kyoo;Choi, Seong-Ho;Kim, Kwan-Suk;Choi, Yang-Il;Kim, Jong-Joo;Lee, Cheol-Koo
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.7
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    • pp.967-971
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    • 2008
  • We compared the fatty acid composition of adipose tissues prepared from Korean native and Yorkshire pigs that have different characteristics in growth and fat deposition. There was no significant difference in the content of most fatty acids between the two breeds, with the exception of arachidonic acid and cis-11,14,17-eicosatrienoic acid. We also investigated the transcriptional levels of genes encoding three different types of oxygenases, including cytochrome P450 (CYP), lipoxygenase and cyclooxygenase, which metabolize arachidonic acid. We found a significant difference in the expression of the CYP genes, CYP2A13, CYP2U1 and CYP3A4, but no differences for the latter two genes between the two breeds. Our results suggest that the difference in arachidonic acid content between the two breeds was caused by differential expression of the CYP genes. Eventually, different levels of EETs and HETEs produced from arachidonic acid by the activity of CYP might contribute partly to the difference of fatness between the two breeds.

Role of Integrin-Linked Kinase in Multi-drug Resistance of Human Gastric Carcinoma SGC7901/DDP Cells

  • Song, Wei;Jiang, Rui;Zhao, Chun-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5619-5625
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    • 2012
  • Gastric carcinoma is a leading cause of cancer death in the world and multi-drug resistance (MDR) is an essential aspect of gastric carcinoma chemotherapy failure. Recent studies have shown that integrin-linked kinase (ILK) is involved in metastasis of human tumors, expression silencing of ILK inhibiting the metastasis of several types of cultured human cancer cells. However, the role and potential mechanism of ILK to reverse the multi-drug resistance in human gastric carcinoma is not fully clear. In this report, we focused on roles of expression silencing of ILK in multi-drug resistance reversal of human gastric carcinoma SGC7901/DDP cells, including increased drug sensitivity to cisplatin, cell apoptosis rates, and intracellular accumulation of Rhodamine-123, and decreased mRNA and protein expression of multi-drug resistance gene (MDR1), multi-drug resistance-associated protein (MRP1), excision repair cross-complementing gene 1 (ERCC1), glutathione S-transferase -${\pi}$ (GST-${\pi}$) and RhoE, and transcriptional activation of AP-1 and NF-${\kappa}B$ in ILK silenced SGC7901/DDP cells. We also found that there was a decreased level of p-Akt and p-ERK. The results indicated that ILK might be used as a potential therapeutic strategy to combat multi-drug resistance through blocking PI3K-Akt and MAPK-ERK pathways in human gastric carcinoma.