• YAKHAK HOEJI
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• v.31 no.2
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• pp.116-125
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• 1987

It is still difficult and time consuming to obtain cDNA sequences that contain the entire nucleotide sequence of the corresponding mRNA. A rapid and high efficient cloning method to obtain full-length cDNA segments is thus developed. The cloning procedure described here consists of the construction of oligo(dT)-tailed vector primer using pWR34 plasmid, polyadenylation of mRNA-cDNA heteroduplex using terminal deoxytransferase, and replacement of MRNA strand with DNA by RNase H and DNA polymerase I. The restriction endonuclease analysis shows that the size of inserted-cDNA is in the range of 1.5~4.0 kb long suggesting that most of cloned cDNA are full-length or nearly full-length cDNA. The plasmid-DNA recombinants obtained were 4$\times$$10^5$~$10^{6}$ per $\mu\textrm{g}$ of rat liver poly (A$^+$)mRNA, which is 4 to 10 fold higher cloning efficiency in comparison to the presently used methods for full-length cDNA cloning. The results indicate that the described cloning system is much simpler, less time consuming, and very efficient cloning method to construct a cDNA library.

• Genomics & Informatics
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• v.10 no.3
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• pp.206-211
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• 2012

DNA barcoding has been widely used in species identification and biodiversity research. A short fragment of the mitochondrial cytochrome c oxidase subunit I (COI) sequence serves as a DNA bio-barcode. We collected DNA barcodes, based on COI sequences from 156 species (529 sequences) of fish, insects, and shellfish. We present results on phylogenetic relationships to assess biodiversity the in the Korean peninsula. Average GC% contents of the 68 fish species (46.9%), the 59 shellfish species (38.0%), and the 29 insect species (33.2%) are reported. Using the Kimura 2 parameter in all possible pairwise comparisons, the average interspecific distances were compared with the average intraspecific distances in fish (3.22 vs. 0.41), insects (2.06 vs. 0.25), and shellfish (3.58 vs. 0.14). Our results confirm that distance-based DNA barcoding provides sufficient information to identify and delineate fish, insect, and shellfish species by means of all possible pairwise comparisons. These results also confirm that the development of an effective molecular barcode identification system is possible. All DNA barcode sequences collected from our study will be useful for the interpretation of species-level identification and community-level patterns in fish, insects, and shellfish in Korea, although at the species level, the rate of correct identification in a diversified environment might be low.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.96-104
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• 2012

Phylogenetic analyses were conducted to evaluate relationships of 7 taxa of Korean Carpesium including three outgroup (Inula britannica L., Inula germanica L., Rhanteriopsis lannginosa (DC.) Rauschert) by using ITS (internal transcribed spacer) sequences of nuclear ribosomal DNA. Phylogenetic studies used maximum parsimony, neighbor-joining and maximum likelihood methods analysis. The length of the ITS sequences was 731 bp, and the lengths of the ITS1, ITS2 and 5.8S regions were 284~297 bp, 264~266 bp and 164 bp, respectively. The total number of variable sites was 111 for the entire sequences, and a parsimony informative sites of 64 are valid. Base change appeared variously in ITS1 rather than in ITS2. As the result, Korean Carpesium were formed monophyletic group and C. abrotanoides situated as the most basal clade. The results show that C. macrocephalum is closely related with C. triste. C. rosulatum has the closest relationship with C. glossophyllum. C. cernuum is close to C. divaricatum. These results suggest that the ITS data used in this study could be useful for the phylogenetic analysis of Korean Carpesium.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.93-97
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• 2003

We describe here the cloning of a cDNA encoding putative calreticulin (CRT) from the silkworm, Bombyx mori. The CRT cDNA comprised of 1,194 bp encoding 398 amino acid residues. B. mori. CRT has a HDEL sequence at the end of the C-domain. The B. morl, CRT showed 88% protein sequence identity to the G. mellonella CRT, 71 % to A. aegypti CRT, and 63% to H. sapiens CRT, Phylogenetic analysis revealed that the deduced amino acid sequences of the B. mori CRT formed a highly inclusive subgroup with other insect CRTs. Northern blot analysis exhibited an expression of the B. mori CRT gene in the fat body, evidencing the fat body as a major site for CRT synthesis.

• Parasites, Hosts and Diseases
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• v.41 no.1
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• pp.47-55
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• 2003

We compared patterns of intraspecific polymorphism of two markers with contrasting modes of evolution, nuclear ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA), in the lung fluke, diploid and triploid Paragonimus westermani from three geographical regions of Korea. The genetic distances between three populations of Korean diploid and triploid P. westermani showed no significant difference in the nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 (mtCOI) and ribosomaal second internal transcribed spacer (ITS2) genes. A highly resolved strict-consensus tree was obtained that illustrated phylogenetically useful information of the ITS2 and mtCOI sequences from diploid and triploid P. westermani.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.145-149
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• 2003

ApolipophorinIII (apoLp-III) is a protypical exchangeable apolipoprotein that is abundant in hemolymph of many insect species. Its function lies in the stabilization of low-density lipophorin particles (LDLp) crossing the hemocoel in phases of high energy consumption to deliver lipids from the fat body to the flight muscle cells. But, recent studies with naive Galleria mellonella-apoLp-III gave first indication of an unexpected role of that protein in insect immune activation. In this research, we cloned a cDNA encoding putative apoLp-III from the silkworm, Bombyx mori injected with E. coli and characterized its role. We constructed a cDNA library using whole bodies of B. mori larvae injected with E. coli, carried out the differential screening, and selected the up-regulated clones. Among these clones, we focused on a cDNA showing a high sequence similarity to the apolipophorinIII from other insects and analyzed the nucleotide and deduced amino acid sequences. The pupative B. mori Jam123 apoLp-III cDNA contained 1,131 bp encoding 186 amino acid residues. Phylogenetic analysis revealed that the nucleotide and amino acid sequences of the B. mori apoLp-III cDNA formed a highly inclusive subgroup with Bombycidae. But, it was interesting that B. mori Jam123 is closer to B. mandarina than B. mori P50 and B. mori N4. Northern blot analysis showed a signal in the fat body, posterior silkgland and midgut.

• Journal of Life Science
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• v.7 no.3
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• pp.167-171
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• 1997

As an initial effort to elucidate RNA: protein binding in a way to regulate translation initiation and phosphorylation, a cDNA encoding a double-stranded RNA binding factor (RBFII)was isolated from Hela ZAPII cDNA library by affinity screening using [$\alpha$$^{-32}$P] UMP-labeled HIV Rev-responsive element(RRE) RNA. The nucleotide sequence of RBF (or TRBP) cDNA except the 5’end. At the 5’end, This common ORF was fused in-frame to N-terminal residues of Lac-Z through a unique 138 nt sequence encoding 46residues in the case of RBFII and a 63 nt sequence encoding 21 residuces in the case of RBFI. The context of ATG appearing first in the sequences suggests that both these cDNA inserts are incomplete at the 5’end.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.235-242
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• 2017

Cudrania tricuspidata Bureau is a widely-used, medicinal, perennial and woody plant. Obtaining information about the genetic diversity of plant populations is highly important with regard toconservation and germplasm utilization. Although C. tricuspidata is an important medicinal plant species registered in South Korea, no molecular markers are currently available to distinguish Korean-specific ecotypes from other ecotypes from different countries. In this study, we developed single nucleotide polymorphism (SNP) markers derived from the chloroplast and nuclear genomic sequences, which serve to to identify distinct Korean-specific ecotypes of C. tricuspidata via amplification refractory mutation system (ARMS)-PCR and high resolution melting (HRM) curve analyses. We performed molecular authentication of twelve C. tricuspidata ecotypes from different regions using DNA sequences in the maturaseK (MatK) chloroplast intergenic region and nuclear ribosomal DNA internal transcribed spacer (ITS) regions. The SNP markers developed in this study are useful for rapidly identifying specific C. tricuspidata ecotypes from different regions.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.529-533
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• 2001

The ${\beta}$-Amylase cDNA fragment from the oomcete Saprolegnia parasitica was cloned by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate oligonucleotide primers derived from conserved ${\beta}$-amylase sequences. The 5'and 3'regions of the $\beta$-amylase gene were amplified using the rapid amplification of cDNA ends (rACE) system. It consisted of an open reading frame of 1,350 bp for a protein of 450 amino acids. Comparison between the genomic and cDNA sequences revealed that the intron was not present in the coding region. The deduced amino acid sequence of the ${\beta}$-amylase gene had a 97% similarity to the ${\beta}$-amylase of Saprolegnia ferax, followed by 41% similarity to those of Arabidopsis thaliana, Hordeum vulgare, and Zea mays. The ${\beta}$-amylase gene was also expressed in Saccharomyces cerevisiae by placing it under the control of the alcohol dehydrogenase gene (ADC1) promoter.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.583-590
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• 2018

Genus Typha L. (Typhaceae; Cattail in common) is one of the hydrophytic plants found in semi-aquatic regions. About nine to 18 species of the genus exist all over the world. In Korea, the most commonly found cattail species are T. laxmanni and T. angustifolia. The aim of this study was to prepare a cDNA library and sequences and analyze expressed sequence tags (ESTs) from these species, T. laxmanni and T. angustifolia. In the case of T. laxmanni, we observed that 715 out of 742 ESTs had high quality sequences, whereas the remaining 27 ESTs were low quality sequences. In this study, we identified 77 contigs, 393 unassembled clones and 65.7% singletons. Furthermore, in the case of T. angustifolia, we recorded 992 high quality EST sequences, and by excluding 28 low quality sequences from among them, we retrieved 120 contigs, 348 unassembled clones and 48.9% singletons. The basic local alignment search tool (BLAST) and Kyoto encyclopedia of genes and genomes (KEGG) database results enabled us to identify the functional categories, i.e., molecular function (16.5%), biological process (22.2%) and cellular components (61.3%). In addition, between these two species, the no hits and anonymous genes were 4.2% and 11.7% and 6.2% and 11.2% in T. laxmanni and T. angustifolia, respectively, based on the BLAST results. The study concluded that they have certain species-specific genes. Hence, the results of this study on these two species could be a valuable resource for further studies.