• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.31-31
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• 1996

The double-stranded panhandle structure of the influenza virus RNA is important for the replication, transcription and packaging into the virion of the vRNA. The solution structure of a 34-nucleotide-long RNA which contains the conserved panhandle sequences has been investigated by one- and two-dimensional NMR spectroscopies. (omitted)

• BMB Reports
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• v.47 no.6
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• pp.330-335
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• 2014

Turnip yellow mosaic virus (TYMV) is a spherical plant virus that has a single 6.3 kb positive strand RNA as a genome. In this study, RNA1 sequence of Flock house virus (FHV) was inserted into the TYMV genome to test whether TYMV can accommodate and express another viral entity. In the resulting construct, designated TY-FHV, the FHV RNA1 sequence was expressed as a TYMV subgenomic RNA. Northern analysis of the Nicotiana benthamiana leaves agroinfiltrated with the TY-FHV showed that both genomic and subgenomic FHV RNAs were abundantly produced. This indicates that the FHV RNA1 sequence was correctly expressed and translated to produce a functional FHV replicase. Although these FHV RNAs were not encapsidated, the FHV RNA having a TYMV CP sequence at the 3'-end was efficiently encapsidated. When an eGFP gene was inserted into the B2 ORF of the FHV sequence, a fusion protein of B2-eGFP was produced as expected.

• BMB Reports
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• v.46 no.10
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• pp.495-500
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• 2013

Turnip yellow mosaic virus (TYMV) is a positive strand RNA virus. We have modified TYMV coat protein (CP) by inserting a c-Myc epitope peptide at the N- or C-terminus of the CP, and have examined its effect on assembly. We introduced the recombinant CP constructs into Nicotiana benthamiana leaves by agroinfiltration. Examination of the leaf extracts by agarose gel electrophoresis and Western blot analysis showed that the CP modified at the N-terminus produced a band co-migrating with wild-type virions. With C-terminal modification, however, the detected bands moved faster than the wild-type virions. To further examine the effect, TYMV constructs producing the modified CPs were prepared. With N-terminal modification, viral RNAs were protected from RNase A. In contrast, the viral RNAs were not protected with C-terminal modification. Overall, the results suggest that virion assembly and RNA packaging occur properly when the N-terminus of CP is modified, but not when the C-terminus is modified.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.86-86
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• 1995

No Abstract, See Full Text

• Journal of Life Science
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• v.7 no.4
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• pp.392-401
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• 1997

The poliovirus is a small, and non-enveloped virus. The RNA genome of poliovirus is continuous, linear, and has a single open reading frame. This polyprotein precursor is cleaved proteolytically to yield mature products. Most of the cleavages occur by viral protease. The mature proteins derived from the P1 polyprotein precursor are the structural components of the viral capsid. The initial cleavage by 2A protease is indirectly involved in the cleavage of a cellular protein p220, a subunit of the eukaryotic translation initiation factor 4F. This cleavage leads to the shut-off of cap-dependent host cell translation, and allows poliovirus to utilize the host cell machinery exclusively for translation its own RNA, which is initiated by internal ribosome entry via a cap-independent mechanism. The functional role of the 2B, 2C and 2BC proteins are not much known. 2B, 2C, 2BC and 3CD proteins are involved in the replication complex of virus induced vesicles. All newly synthesized viral RNAs are linked with VPg. VPg is a 22 amino acid polypeptide which is derived from 3AB. The 3C and 3CD are protease and process most of the cleavage sites of the polyprotein precursor. The 3C protein is also involved in inhibition of RNA polymerase II and III mediated transcription by converting host transcription factor to an inactive form. The 3D is the RNA dependent RNA polymerase. It is known that poliovirus replication follows the general pattern of positive strand RNA virus. Plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA strands. Poliovirus RNA synthesis occurs in a membranous environment but how the template RNA and proteins required for RNA replication assemble in the membrane is not much known. The RNA requirements for the encapsidation of the poliovirus genome (packaging signal) are totally unknown. The poliovirus infection cycle lasts approximately 6 hours.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.171-174
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• 2012

THOC1/Hpr1 is one subunit of THO complex that is an evolutionally conserved assembly involved in the mRNP packaging and mRNA export during transcription elongation. In fission yeast Schizosaccharomyces pombe, an ortholog (spHpr1) of THOC1/Hpr1 was identified based on sequence alignment. A deletion mutant in a diploid strain was constructed by replacing one of spHpr1-coding region with a $kan^r$ gene using one-step gene disruption method. Tetrad analysis showed that the sphpr1 is essential for growth. Over-expression of sphpr1 from strong nmt1 promoter caused no defects of growth and mRNA export. However, repression of the sphpr1 expression resulted in growth inhibition accompanied by accumulation of poly$(A)^+$ RNA in the nucleus. These results suggest that spHpr1 is involved in mRNA export from the nucleus to cytoplasm.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.249-253
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• 2014

THOC7/Mft1 is a member of the THO complex that is an evolutionally conserved assembly connecting transcription elongation with mRNP packaging and mRNA export. In fission yeast Schizosaccharomyces pombe, an ortholog (spThoc7) of THOC7/Mft1 was isolated by partial complementation of the lethality in synthetic lethal mutant, SLRsm1. A deletion mutant in a diploid strain was constructed by replacing one of spThoc7-coding region with an $ura4^+$ gene using one-step gene disruption method. Tetrad analysis showed that the spthoc7 is nonessential for growth. But the ${\Delta}thoc7$ null mutant showed slight defects of both growth and mRNA export. And the functional spThoc7-GFP protein is localized mainly in the nucleus. These results suggest that spThoc7 is also involved in mRNA export from the nucleus to cytoplasm.

• BMB Reports
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• v.41 no.7
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• pp.511-515
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• 2008

The nucleocapsid (NC) protein of the Human Immunodeficiency Virus-1 plays a key role in viral genomic packaging by specifically recognizing the Psi($\Psi$) RNA sequence within the HIV-1 genome RNA. Recently, a novel cell-based assay was developed to probe the specific interactions in vivo between the NC and $\Psi$-RNA using E.coli cells (J. Virol. 81: 6151-55, 2007). In order to examine the extendibility of this cell-based assay to RNAs other than $\Psi$-RNA, this study tested the RNA aptamers isolated in vitro using the SELEX method, but whose specific binding ability to NC in a living cellular environment has not been established. The results demonstrate for the first time that each of those aptamer RNAs can bind specifically to NC in a NC zinc finger motif dependent manner within the cell. This confirms that the cell-based assay developed for NC-$\Psi$interaction can be further extended and applied to NC-binding RNAs other than $\Psi$-RNA.

• Journal of the Korean Magnetic Resonance Society
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• v.5 no.1
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• pp.29-36
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• 2001

The structures of two VBS (viral binding site) RNAs, SL1 and SL2, of Yeast Saccharomyces cerevisiae vims have been studied by 2D and 3D NMR experiments. VBSs play a crucial role in viral particle binding to the plus strand and packaging of the RNA. The secondary structures of the two VBS RNAs share a common feature of the stem-internal loop-stem-hairpin loop structure although the size of the internal loops of SL1 and SL2 differs. 2D experiments were sufficient for fill assignments of SL1. However, isotope labeling of the sample and multidimensional experiments were required for 28-nucleotide-long SL2 due to the spectral overlap. Several 3D HCCH experiments have accomplished full assignment of SL2 RNA.

• Korean Journal of Veterinary Research
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• v.39 no.4
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• pp.797-805
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• 1999

T sergenti cDNA library were constructed to get a more broad information about the structural, functional or antigenic properties of the proteins, and analyzes for their partial cDNA sequences and expression sequences tags(ESTg). The mRNA were purified from T sergenti isolates to identify the information of antigen gene, then first and second strand cDNA was synthesized. EcoR I adaptor ligation and Xho I enzyme restriction were used to the synthesized cDNA, and ligated into a Uni-ZAP XR vector. T sergenti cDNA library was constructed with packaging and amplification in vitro. Antibody screening was performed with constructed T sergenti cDNA library using antisera against T sergenti. Among those clones, eight phagemids were rescued from the recombinant in vivo excision with f1 helper phage. Using the analysis of endonuclease restriction and PCR, the recombinant cDNA were proved having a 0.5-3.0kb of inserts. The eight of partial cDNA clones' sequences were obtained and examined for their homology using BLASTN and BLASTX. The eight of sequenced clones were classified into three groups according to the basis of database searches. A total 3,045bp of partial cDNA sequence were determined from six clones. The putatively identified clones contain a cytochrome c gene, a heat shock protein gene, a cyclophilin gene, and a ribosomal protein gene. The unidentified clones have a homology to ATP-binding protein(mtrA) gene of S argillaceus, DNA-binding protein(DBP) gene of Pseudorabies virus 85kDa merozoite protein gene of B bovis, mRNA spm1 protein of T annulata and glycine-rich RNA-binding protein mRNA of O sativa etc.