• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1193-1194
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• 2009

• Bulletin of the Korean Chemical Society
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• v.29 no.11
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• pp.2227-2230
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• 2008

• Molecules and Cells
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• v.21 no.1
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• pp.63-75
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• 2006

The 5′-region of Potato virus X (PVX) RNA, which contains an AC-rich, single-stranded region and stem-loop structure 1 (SL1), affects RNA replication and assembly. Using Systemic Evolution of Ligands by EXponential enrichment (SELEX) and the electrophoretic mobility shift assay, we demonstrate that SL1 interacts specifically with tobacco protoplast protein extracts (S100). The 36 nucleotides that correspond to the top region of SL1, which comprises stem C, loop C, stem D, and the tetra loop (TL), were randomized and bound to the S100. Remarkably, the wild-type (wt) sequence was selected in the second round, and the number of wt sequences increased as selection proceeded. All of the selected clones from the fifth round contained the wt sequence. Secondary structure predictions (mFOLD) of the recovered sequences revealed relatively stable stem-loop structures that resembled SL1, although the nucleotide sequences therein were different. Moreover, many of the clones selected in the fourth round conserved the TL and C-C mismatch, which suggests the importance of these elements in host protein binding. The SELEX clone that closely resembled the wt SL1 structure with the TL and C-C mismatch was able to replicate and cause systemic symptoms in plants, while most of the other winners replicated poorly only on inoculated leaves. The RNA replication level on protoplasts was also similarly affected. Taken together, these results indicate that the SL1 of PVX interacts with host protein(s) that play important roles related to virus replication.

• Journal of Life Science
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• v.23 no.10
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• pp.1260-1266
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• 2013

The ribosomal DNA (rDNA) clusters of Hypsizygus marmoreus 3-10 and H. marmoreus 1-1 were analyzed in this study. The small subunit (SSU) and intergenic spacer 2 (IGS 2) was partially sequenced. The internal transcribed spacer 1 (ITS 1), 5.8S, internal transcribed spacer 2 (ITS 2), large subunit (LSU), intergenic spacer 1 (IGS 1), and 5S were completely sequenced. The rDNA clusters of H. marmoreus 3-10 and H. marmoreus 1-1 were 7,049 bp in length. The sequence of SSU rDNA, which corresponded to 18S rDNA, was 1,796 bp in length, and the sequence of LSU rDNA, which corresponded to 28S rDNA, was 3,348 bp in length. The ITS region that variable region and IGS region that non-transcribed spacer was 462 bp and 1,290 bp in length. The sequence of 5.8S rDNA and 5S rDNA was 153 bp and 43 bp in length, respectively. The 17 bp of the rDNA cluster in the H. marmoreus 3-10 strain was different to that in the H. marmoreus 1-1 strain, with 2 bp in the SSU, 3 bp in the ITS, 9 bp in the LSU, and 3 bp in the IGS. The analysis of the secondary structure revealed that the ITS regions of H. marmoreus 3-10 and H. marmoreus 1-1 have five stem-loop structures. Interestingly, among these structures, one different nucleotide sequence resulted in a different secondary structure in stem-loop V.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.211-217
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• 1999

Effects of subsh-ate RNA configuration on the tians-splicing reactcon by group I intron ribozyme of Tetralzynzena thern\ulcornerophila were analyzed with substrate RNAs which have been generated to have very stable structures with stem-loop. RNAinapping strategy was perfo~med in vivo as well as in virro to search the mosl accessible siles to the ~irms-splicing ribozymes in the substrate RNAs. Sequences present in the loop of the target RNAs have shown to be well recognized by and reacted with group I inlron ribozymes while sequences present in the stein do not. Thesc results were confirmed with the experiments of trans-cleavage and rmnssplicing reactmn with ihe specific ribozyines recognizing those sequences. Moreover, sequence analysis of the trans-splicing products have shown that irons-splicing reaction can proceed with high fidelity. In conclusion, the secondary structure of substrate RNAs is one of the most important factors to detemine the ribozyme activity.

• Molecules and Cells
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• v.19 no.1
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• pp.104-113
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• 2005

Large inversions are well characterized in the chloroplast genomes of land plants. In contrast, reports of small inversions are rare and involve limited plant groups. In this study, we report the widespread occurrence of small inversions ranging from 5 to 50 bp in fully and partially sequenced chloroplast genomes of both monocots and dicots. We found that small inversions were much more common than large inversions. The small inversions were scattered over the chloroplast genome including the IR, SSC, and LSC regions. Several small inversions were uncovered in chloroplast genomes even though they shared the same overall gene order. The majority of these small inversions were located within 100 bp downstream of the 3' ends of genes. All had inverted repeat sequences, ranging from 11 to 24 bp, at their ends. Such small inversions form stem-loop hairpin structures that usually have the function of stabilizing the corresponding mRNA molecules. Intra-molecular recombination between the inverted sequences in the stem-forming regions are responsible for generating flip-flop orientations of the loops. The presence of two different orientations of the stem-loop in the trnL-F noncoding region of a single species of Jasminum elegans suggests that a short inversion can be generated within a short period of time. Small inversions of non-coding sequences may influence sequence alignment and character interpretation in phylogeny reconstructions, as shown in nine species of Jasminum. Many small inversions may have been generated by parallel or back mutation events during chloroplast genome evolution. Our data indicate that caution is needed when using chloroplast non-coding sequences for phylogenetic analysis.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.125-128
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• 2005

A 16S ribosomal RNA gene from S. chungbukensis DJ77 has been sequenced. This sequence had a length of 1,502 bp and was extended for 29 bp at 5' and for 37 bp at 3' from the partial sequence (1,435 bp) registered in 2000 year. Besides, 1 bp was newly added near to the 3' end. We made the secondary structure of the 16S rRNA based on E. coli model and found four specific regions. We found constant and variable regions in genus Sphingomonas as the result of multiple alignment of 16S rRNA gene sequences from Sphingomonas spp. and S. chungbukensis DJ77. We found a stem loop structure in S. chungbukensis DJ77, which was only discovered in C. jejuni to date. It showed the structural agreement despite the difference of the sequences from the both organisms. Finally, S. chungbukensis DJ77 belonged to cluster II (Sphingobium) group, after the classification using phylogenetic analysis and nucleotide signature analysis.

• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.62-65
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• 1999

Iron regulatory proteins (IRPs) 1 and 2 bind with equally high affinity to specific RNA stem-loop sequences known as iron-responsive elements (IRE) which mediate the post-transcriptional regulation of many genes of iron metabolism. To study putative IRE-like sequences in RNA transcripts using the IRP-IRE interaction, Eight known genes from database were selected and the RNA binding activity of IRE-like sequences were compared to IRP-2. Among them, the IRE-like sequence in 3'-untranslational region (UTR) of divalent ration transporter-1 (DCT-1) shows a significant RNA binding affinity. This finding predicts that IRE consensus sequence present within 3'-UTR of DCT-1 might confer the regulation by IRP-2.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.28-33
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• 1998

A gene coding for ${\beta}$-xylosidase from thermophilic xylanolytic Bacillus sp. KK-1 was cloned into Escherichia coli using plasmid pBR322. Recombinant plasmid DNAs were isloated from E. coli clones which were capable of hydrolyzing 4-methylumbelliferyl-${\beta}$-D xylopyranoside. Restriction analysis showed the DNAs to share a common insert DNA. Xylo-oligosaccharides, including xylotriose, xylotetraose, xylopentaose, and xylobiose were hydrolyzed to form xylose as an end product by cell-free extracts of the E. coli clones, confirming that the cloned gene from strain KK-1 is ${\beta}$-xylosidase gene. The ${\beta}$-xylosidase gene of strain KK-1 designated as xylB was completely sequenced. The xylB gene consisted of an open reading frame of 1,602 nucleotides encoding a polypeptide of 533 amino acid residues, and a TGA stop codon. The 3' flanking region contained one stem-loop structure which may be involved in transcriptional termination. The deduced amino acid sequence of the KK-1 ${\beta}$-xylosidase was highly homologous to the ${\beta}$-xylosidases of Bacillus subtilis and Bacillus pumilus, but it showed no similarity to a thermostable ${\beta}$-xylosidase from Bacillus stearothermophilus.

• Molecules and Cells
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• v.27 no.4
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• pp.429-441
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• 2009

We have determined the complete mitochondrial genome of the yellow-spotted long horned beetle, Psacothea hilaris (Coleoptera: Cerambycidae), an endangered insect species in Korea. The 15,856-bp long P. hilaris mitogenome harbors gene content typical of the animal mitogenome and a gene arrangement identical to the most common type found in insect mitogenomes. As with all other sequenced coleopteran species, the 5-bp long TAGTA motif was also detected in the intergenic space sequence located between $tRNA^{Ser}$(UCN) and ND1 of P. hilaris. The 1,190-bp long non-coding A+T-rich region harbors an unusual series of seven identical repeat sequences of 57-bp in length and several stretches of sequences with the potential to form stem-and-loop structures. Furthermore, it contains one $tRNA^{Arg}$-like sequence and one $tRNA^{Lys}$-like sequence. Phylogenetic analysis among available coleopteran mitogenomes using the concatenated amino acid sequences of PCGs appear to support the sister group relationship of the suborder Polyphaga to all remaining suborders, including Adephaga, Myxophaga, and Archostemata. Among the two available infraorders in Polyphaga, a monophyletic Cucujiformia was confirmed, with the placement of Cleroidea as the basal lineage for Cucujiformia. On the other hand, the infraorder Elateriformia was not identified as monophyletic, thereby indicating that Scirtoidea and Buprestoidea are the basal lineages for Cucujiformia and the remaining Elateriformia.