• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.183-190
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• 1994

Cell-free extracts prepared from cultured insect cells, Spodoptera. frugiperda, were analyzed for activation of early gene transcription of an insect baculovirus, Autographa californica nuclear polyhedrosis virus (AcNPV). The template DNA used for in vitro transcription assays contained promoter sites for the baculovirus genes that have been classified as immediate early ($\alpha$) or early genes. These genes are located in the HindIII-K/Q region of the AcNPV genome. Nuclei isolated from the AcNPV-infected Spodoptera frugiperda cells were also used for in vitro transcription analysis by RNase-mapping the labeled RNA synthesized from in vitro run-on reaction in the isolated nuclei. The genes studied by this technique were p26 and pl0 genes which were classified as delayed early and late gene, respectively. We found that transcription of the genes from the HindIII-K region was accurately initiated and unique in the whole cell extract obtained from uninfected cells, although abundance of the in vitro transcripts was reverse to that of in vivo RNA. With isolated nuclei transcription of the p26 gene was inhibited by $\alpha$-amanitin suggesting that the p26 gene was transcribed by host RNA polymerase II. However, transcription of the pl0 gene in isolated nuclei was not inhibited by $\alpha$-amanitin, but rather stimulated by the inhibitor. We also found that the synthesis of $\alpha$-amanitin-resistant RNA polymerase was begun before 6 hr p.i., the time point at which the onset of viral DNA replication as well as the appearance of a-amanitin-resistant viral transcripts were detected. These studies give us strong evidence to support the previous data that early genes of AcNPV were transcribed by host RNA polymerease III, while transcription of late genes was mediated at least by a novel $\alpha$-amanitin-resistant RNA polymerase.

• Genomics & Informatics
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• v.13 no.2
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• pp.26-30
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• 2015

nc886 (=vtRNA2-1, pre-miR-886, or CBL3) is a newly identified non-coding RNA (ncRNA) that represses the activity of protein kinase R (PKR). nc886 is transcribed by RNA polymerase III (Pol III) and is intriguingly the first case of a Pol III gene whose expression is silenced by CpG DNA hypermethylation in several types of cancer. PKR is a sensor protein that recognizes evading viruses and induces apoptosis to eliminate infected cells. Like viral infection, nc886 silencing activates PKR and induces apoptosis. Thus, the significance of the nc886:PKR pathway in cancer is to sense and eliminate pre-malignant cells, which is analogous to PKR's role in cellular innate immunity. Beyond this tumor sensing role, nc886 plays a putative tumor suppressor role as supported by experimental evidence. Collectively, nc886 provides a novel example how epigenetic silencing of a ncRNA contributes to tumorigenesis by controlling the activity of its protein ligand.

• BMB Reports
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• v.41 no.5
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• pp.358-362
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• 2008

RNA interference (RNAi) is the process of sequence-specific gene silencing. However, RNAi efficiency still needs to be improved for effective inhibition of target genes. We have developed an effective strategy to express multiple shRNAs (small hairpin RNA) simultaneously using multiple RNA Polymerase III (Pol III) promoters in a single vector. Our data demonstrate that multiple shRNAs expressed from Pol III promoters have a synergistic effect in repressing the target gene. Silencing of endogenous cyclophilin A (CypA) or key HIV viral genes by multiple shRNAs results in significant inhibition of the target gene.

• Korean Journal of Plant Tissue Culture
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• v.27 no.5
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• pp.379-385
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• 2000

tRNA and 7SL RNA based antisense vehicles were prepared by inserting conserved anti-viral and anti-viroid domains. Anti-PVS coat protein leader sequence (ACPL) and antistructural antihairpin domain of PSTVd (AHII) were inserted in tRNA cassette; anti- zing finger domain of PVS, AHII and anti hop latent viroid ribozyme were inserted in 7SL RNA gene isolated from A. thaliana. These constructs were shown to be transcribed both, in in vitro and in in vivo conditions. However, it followed from our work that closely linked position of PoIII reference genes and PoIIII antisense genes within T-DNA lead to the impairment of RNA expression in transgenic plants. To assay in vivo transcription of antisense genes, hairy root potato cultures were established using h. tumefaciens A4-24 bearing both, Ri plasmid and PoIII-promoterless plant expression vectors with antisense RNA genes. Expression of antisense RNA in transgenic potato tissues was proven by specific RT-PCR reactions.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.228-234
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• 1994

Genomic RNA was extracted from Cy strain of odontoglossum ringspot tobamovirus (ORSV-Cy) isolated from infected leaves of tobacco cv. Samsun. Size of the genomic RNA was about 6.6 kb in length. The genomic RNA was fractionated using Sephadex G-50 column chromatography into 2 fractions. They were polyadenylated at their 3'-end using E. coli poly(A) polymerase. Polyadenylated viral RNA was recovered by oligo (dT) primer adapter containing NotI restriction site and Moloney murine leukemia virus SuperScript reverse transcriptase (RNase H-). Second-strand cDNA was synthesized by using E. coli DNA ligase, E. coli DNA polymerase I and E. coli RNase H. Recombinant plasmids containing cDNAs for ORSV-Cy RNA ranged from about 800 bp to 3,000 bp. Among the selected 238 recombinants, pORCY-124 clone was the largest one covering 3'-terminal half of the viral RNA. This clone contained two restriction sites for EcoRI and XbaI and one site for AccI, AvaI, BglII, BstXI, HindIII, PstI, and TthIII 1. respectively. The clone contained partial viral replicase, a full-length movement protein and a complete coat protein genes followed by a 3' untranslated region of 414 nucleotides based on restriction mapping and nucleotide sequencing analyses. Clones pORCY-028, -068, -072, -187 and -224 were overlapped with the pORCY-124. Clones pORCY-014 and -095 covered 5' half upstream from the middle region of the viral RNA, which was estimated based on restriction mapping and partial sequence analysis. Constructed cDNA library covered more than 90% of the viral genome.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.37-41
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• 2001

Two linear plasmid-like DNAs, 10.2 kb and 7.2 kb were found in the mitochondria of P. ostreatus. They have covalently linked 5'-terminal proteins in both ends. Two continuous fragments of 4.7 kb and 2.3 kb from 7.2 kb DNA were cloned and sequenced. Two long open reading frames (ORF1; 2982 bp, 993 a.a and ORF2; 2703 bp, 900 a.a) and one short open reading frame(ORF3; 771 bp, 256 a.a) were found in the 7.2 kb plasmid. The putative ORF1 and ORF2 have conserved motifs of DNA polymerases and RNA polymerases, respectively, while the ORF3 has homologous regions with phosphatase from Plasmodium, and also with adhesine from Mycoplasma.

• Journal of Life Science
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• v.30 no.1
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• pp.88-95
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• 2020

Using a random arbitrarily primed polymerase chain reaction, messenger RNA expression levels were assessed after exposure to 10% (v/v) toluene for 8 hr in solvent-tolerant Pseudomonas sp. BCNU 106. Among the 100 up-expressed products, 50 complementary DNA fragments were confirmed to express repeatedly; these were cloned and then sequenced. Blast analysis revealed that toluene stimulated an adaptive increase in the gene expression level in association with transcriptions such as LysR family of transcriptional regulators and RNA polymerase factor sigma-32. The expression of catalase and Mn2+/Fe2+ transporter genes functionally associated with inorganic ion transport and metabolism increased, and the increased expression of type IV pilus assembly PilZ and multi-sensor signal transduction histidine kinase genes, functionally categorized into signal transduction and mechanisms, was also demonstrated under toluene stress. The gene expression level of beta-hexosaminidase in association with carbohydrate transport and metabolism increased, and those of DNA polymerase III subunit epsilon, DNA-3-methyladenine glycosylase II, DEAD/DEAH box helicase domain-containing protein, and ABC transporter also increased after exposure to toluene in DNA replication, recombination, and repair, and even in defense mechanism. In particular, the RNAs corresponding to the ABC transporter, Mn2+/Fe2+ transporter, and the β-hexosaminidase gene were confirmed to be markedly induced in the presence of 10% toluene. Thus, defense mechanism, cellular ion homeostasis, and biofilm formation were shown as essential for toluene tolerance in Pseudomonas sp. BCNU 106.

• Journal of Life Science
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• v.8 no.2
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• pp.126-130
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• 1998

A pair of designed primers (sequences from Gene Bank) amplified 16S fRNA gene of V. vulnificus within polymerase chain reaction (PCR) machine. This PCR product is about 1.3kb DNA fragment. Six enzymes (BamH I, Alu I, Sau3A I, Hind III, Sal I, Sma I) were used for restriction pattern analysis of amplified 16S rRNA gene of V. vulnificus ATCC 27562. Digested fragments are resolved by 3% agarose gel. BamH I did not show digested fragment so, there was no cutting site of BamH I in PCR product. Alu I produced three small fragments from 400 bp to 200 bp. Sau3A I produced three fragments larger than Alu I from 70 bp and 500 bp. One of fragments of Sal I was same with 500 bp of Hind III fragment and the other was 750 bp. Sma I showed two fragments of 800 bp and 470 bp. The profile of digested fragments of 16S rRNA of V.vulnificus ATCC 27562 will may be able to use standard profile for identification of V. vulnificus.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.1028-1039
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• 2004

During the past 65 million years, Alu sequences have been amplified through RNA-polymerase IIIderived transcripts, and have reached the copy number of about 1.4 million in primate genomes. They are the largest family among mobile genetic elements in human genome and consist of ten percent of the human genome. Alu sequences are thought to be functionless genetically, but many researchers have proved new function and disease implication. Alu elements make the genome insertional mutation, Alu-mediated recombination events, and unexpected splicing site and change gene structures, protein sequences, splicing motifs and expression patterns. In this review, the structure and origin of Alu, consensus sequences of Alu subfamilies, evolution and distribution of Alu, and their related diseases were described. We also indicated new research direction of Alu elements in relation to evolution and disease.

• Journal of Plant Biology
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• v.38 no.3
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• pp.267-274
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• 1995

Based upon the nucleotide sequence of As strain of cucumber mosaic virus (CMV-As0 RNA4, coat protein (CP) gene was selected for the design of oligonucleotide primers of polymerase chain reaction (PCR) for detection and identification of the virus. Reverse transcription and polymerase chain reaction (RT-PCR) was performed with a set of 18-mer CMV CP-specific primers to amplify a 671 bp fragment from crude nucleic acid extracts of virus-infected leaf tissues as well as purified viral RNAs. The minimum concentrations of template viral RNA and crude nucleic acids from infected tobacco tissue required to detect the virus were 1.0 fg and 1:65,536 (w/v), respectively. No PCR product was obtained when potato virus Y-VN RNA or extracts of healthy plants were used as templates in RT-PCR using the same primers. The RT-PCR detected CMV-Y strain as well as CMV-As strain. Restriction analysis of the two individual PCR amplified DNA fragments from CMV-As and CMV-Y strains showed distinct polymorphic patterns. PCR product from CMV-As has a single recognition site for EcoRI and EcoRV, respectively, and the product from CMV-Y has no site for EcoRI or EcoRV but only one site for HindIII. The RT-PCR was able to detect the virus in the tissues of infected pepper, tomato and Chinese cabbage plants.