• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.271-277
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• 1995

The RNA nucleotide sequences of the 3/-noncoding regions (3'-NCRs) of two Korean strains of turnip mosaic virus (TuMV), Ca and cqs, have been determined from their cDNA clones that encompassed the 3'-terminal regions of the viral genomic RNAs. The 3'-NCRs of both strains were 209 nucleotides long, terminated with GAC residues and poly (A) tails. The potential polyadenylational signal motif, UAUGU, was located 140 nucleotides upstream from the poly (A) tail in each of the virus. A highly conserved hexanucleotide sequence [A G U G A/U G/C], which was common in the 3'-NCRs of the potyvirus RNAs, was also found at the regions of 119 bases upstream from the 3'-end. Comparison of the 3'-NCRs of the two Korean isolates with those of four strains from Canada, China and Japan showed significantly identical genotypes (94.3∼99.5%). The secondary structure of three loops with long stems was found within the 3'-NCRs by sequence analysis. The substituted bases in the region among the six TuMV strains did not alter their secondary structures. Length of the 3'-NCRs of the know 11 potyviral RNAs and TuMV RNAs was different from one another and their nucleotide sequences showed 55.7% to 24.0% of homology. The 3'-NCR, therefore, is considered to be useful for phylogenetic studies in potyviruses.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.1-9
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• 1989

The locations of 5' ends as well as the splicing pattern of viral poly A(-) 19S RNA from monkey cells infected with SV40 were determined by a modification of primer extension method. The 5' end of this RNA mapped at the major cap site at nucleotide residue 325, used most frequently by SV40 late RNAs. The intron from nt.373 to nt.558 was removed as the ordinary cytoplasmic poly A(+) 19S RNA. The 3'end of this RNA was very heterogeneous and distributed over 1 kb upstream of polyadenylation site, as determined by S1 nuclease mapping. The reason for this normally initiated and spliced RNA to accumulate in the nucleus was investigated. In order to test whether the presence of unused 3' splice region on this RNA caused such subcellular distribution, cells were transfected with SV40 mutant KNA containing deletion around 3' splice site. The RNA deleted of 3' splice region accumulated mainly in the cytoplasm. This accumulation did not result from the increased stability of the RNA due to the deletion, since the wild type and mutant RNAs exhibited similar half lives after chase with actinomycin D. Therefore it is likely that the 19S spliced RNA is hindered from being transported into the cytoplasm due to some pre-splicing complexes formed at the unused 3' splice site.

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.189-200
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• 1993

Ornithine decarboxylase is the first and rate limiting enzyme in the biosynthesis of polyamines in mammalian cells. During cell growth the enzyme is regulated by rapid changes in the level of its mRNA and protein. To explore the molecular basis of these changes, ODC-specific complementary DNA (cDNA) clones were isolated from a bovine cDNA library. This region of the cDNA contained a portion of the open reading frame, a 3'noncoding region, and a poly-A tail of 456, 348, and 14 nucleotides, respectively. A comparison of the deduced sequence of the carboxyl terminal 151 amino acids of ODC with amino acid sequences in the same region of the enzyme from human, mouse, rat, and hamster showed greater than 88% identity in these proteins. The highly conserved nature of the amino acid sequences may be related to the important role of ODC in cell growth and differentiation.

• Membrane Journal
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• v.13 no.4
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• pp.291-299
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• 2003

Polymer membranes such as poly(1-trimethylsilyl-1-propyne)-polyetherimide (PTMSP-PEI) and poly(dimethylsiloxane)- polyetherimide (PDMS-PEI) composite membrane were prepared by solution casting method. To investigate the characteristics of these membranes, the analytical methods such as FT-IR, $^1H-NMR,$ DSC, TGA, GPC, and SEM have been utilized. The number-average (equation omitted) and weight-average (equation omitted) molecular weight of PTMSP were 477,920 and 673,329 respectively. The glass transition temperature ($T_g$) of PTMSP was $224^{\circ}C.$ The separation of the gas mixture ($H_2/N_2$) through the composite membranes were studied as a function of pressure. The separation factor (${\alpha}, {\beta},$ quation omitted) of the composite membranes used in this work increased as the pressure of permeation cell increased. The real separation factor (${\alpha}$), head separation factor (${\beta}$), and tail separation factor (equation omitted) of PTMSP-PEI composite membrane were 2.28, 1.17, and 1.96 respectively at ${\Delta}P$ 30psi and $25^{\circ}C.$ (${\alpha}, {\beta}$ and equation omitted of PDMS-PEI composite membrane were 3.70, 1.53, and 2.42 respectively at ${\Delta}P$ 30psi and $25^{\circ}C$.

• BMB Reports
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• v.50 no.4
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• pp.194-200
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• 2017

Eukaryotic gene expression is precisely regulated at all points between transcription and translation. In this review, we focus on translational control mediated by the 3'-untranslated regions (UTRs) of mRNAs. mRNA 3'-UTRs contain cis-acting elements that function in the regulation of protein translation or mRNA decay. Each RNA binding protein that binds to these cis-acting elements regulates mRNA translation via various mechanisms targeting the mRNA cap structure, the eukaryotic initiation factor 4E (eIF4E)-eIF4G complex, ribosomes, and the poly (A) tail. We also discuss translation-mediated regulation of mRNA fate.

• Membrane Journal
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• v.14 no.4
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• pp.304-311
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• 2004

The poly(1-trimethylsilyl-1-propyne) (PTMSP) and silica-filled PTMSP membranes were prepared by casting from a toluene solution on porous polyetherimide (PEI). FT-IR spectrum, GPC and SEM pictures have been taken to characterize the membranes. The particle size of membrane decreases as silica content of the membrane increases from 23 to 60 wt%, and a uniform distribution of the silica is observed. The separation properties of the gas mixture (32 mol% $H_2$/ 68 mol% $N_2$) through the composite membranes were studies as a function of pressure and percentage of silica. Selectivity values of $H_2$/$N_2$ increased as the pressure of permeation cell and silica content of the membrane increased. The real separation factor($\alpha$), head separation factor($\beta$), and tail separation factor((equation omitted)) of PTMSP-PEI composite membrane were 2.28, 1.58, and 1.44 respectively at $\Delta$P 30 psi and $25^{\circ}C$. $\alpha$, $\beta$, and (equation omitted) of PTMSP-Silica-PEI composite membrane for 60 wt% silica were 3.34, 1.95, 1.72 at $\Delta$P 30 psi and $25^{\circ}C$.

• Journal of Plant Biology
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• v.39 no.1
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• pp.9-13
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• 1996

A clone, LCM1, which encodes calmodulin (CaM) was isolated and characterized from monocot lily (Lilium longiflorum Thunb.) plants. The clone is 681 bps and contains the 447 bp coding region, 8 bp leader sequence, 210 bp 3'-untraslated region, and a poly(A) tail. The coding region of 149 amino acids encodes a protein of predicted Mr 17 kD. Comparison of the LCM1 amino acid sequence with other CaMs revealed that the protein is highly conserved among various living organisms. The expression level of calmodulin gene in lily was studied by RNA blot analysis. The LCM1 mRNA was present in all tissues tested. However, a higher level of calmodulin was observed in anther and floral bud. The level of calmodulin mRNA in anther was about 10 times higher than that in anther was about 10 times higher than that in vegetative tissues. The anther preferential expression of CaM in lily is currently investigated in dicot plants.

• BMB Reports
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• v.32 no.4
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• pp.345-349
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• 1999

We fused the promoter region of an H3.2 chicken histone gene, whose expression is dependent on the cell cycle, to the 5' coding region of an H3.3 chicken histone gene, which is expressed constitutively at a low level throughout the cell cycle. This fusion gene showed a cell cycle-regulated pattern of expression, but in a different manner. The mRNA level of the fusion gene increase during the S phase of the cell cycle by about 3.7-fold at 6 h and 2.7-fold at 12 h after the serum stimulation. The mRNA level of the intact H3.2 gene, however, increased by an average of 3.6-fold at 6 h and 8.7-fold at 12 h. This different expression pattern might be due to the differences in their 3' end region that is responsible for mRNA stability. The 3' end of the H3.2 mRNA contains a stem-loop structure, instead of a poly(A) tail present in the H3.3 mRNA. We also constructed a similar fusion gene using a H3.3 histone gene whose introns had been eliminated to rule out the possibility of involvement of the introns in cell cycle-regulated expression. The expression of this fusion gene was almost identical to the fusion gene made previously. These results indicate that the promoter region of the H3.2 gene is only partially responsible for its expression during the S phase of the cell cycle.

• The Korean Journal of Zoology
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• v.28 no.3
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• pp.166-178
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• 1985

In order to express hepatitis B surface antigen $(HB_sAg)$ containing pre-surface antigen region in mammalian calls, 2.7 kb DNA fragment containing pre-surface region-$HB_sAg$ gene poly(A) addition site of HBV genome was cloned into simian virus 40(SV 40) based chimeric vector pSVOB. 2.7 kb DNA fragment was derived from pHBVD 107 containing tandem copies of the HBV genome in a head-to-tail arrangement by Bgl II digestion. Construction of the vector pSVOE involved the incorporation of SV40 sequences spanning the viral origin of replication and 72 bp repeats (enhancer) into a pBR 322 derivative lacking sequences which inhibit replication in mammalian cells. Bam HI linker was inserted at the Pvu II site in the proximity of SV40 late promoter of pSVOE and named as pSVOB. To construct the recombinant plasmid pSVBS, pHBVD 107 was digested with Bgl II to isolate 2.7kb DNA fragment and the fragment was ligated into the Bam HI site of pSVOB by ligation. Preliminary result showed that the recombinant plasmid pSVBS produced $HB_sAg$ in the monkey cell producing large T antigen (COS cell).

• The Plant Pathology Journal
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• v.24 no.3
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• pp.361-364
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• 2008

The complete nucleotide sequences of a Korean isolate of Potato virus X(PVX-Kr) has been determined. Full-length cDNA of PVX-Kr has been directly amplified by long template reverse transcription and polymerase chain reaction(RT-PCR) using virus specific 5'-end primer and 3'-end primer, and then constructed in a plasmid vector. Consecutive subclones of a full-length cDNA clone were constructed to identify whole genome sequence of the virus. Total nucleotide sequences of genome of PVX-Kr were 6,435 excluding one adenine at poly A tail, and genome organization was identical with that of typical PVX species. Comparison of whole genome sequence of PVX-Kr with those of European and South American isolates showed 95.4-96.8% and 77.4-77.9%, in nucleotide similarity, respectively. Sequenced PVX-Kr in this study and twelve isolates already reported could be divided into two subgroups in phylogeny based on their complete nucleotide sequences. Phylogenetic tree analysis demonstrated that PVX-Kr was clustered with European and Asian isolates(Taiwan, os, bs, Kr, S, X3, UK3, ROTH1, Tula) in the same subgroup and South American isolates(CP, CP2, CP4, HB) were clustered in the other subgroup.