• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.4 s.304
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• pp.33-42
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• 2005

This paper proposes a classification method for gene expression data, using membership function and neural network. The gene expression is a process to produce mRNA and protains which generate a living body, and the gene expression data is important to find out the functions and correlations of genes. Such gene expression data can be obtained from DNA 칩 massively and quickly. However, thousands of gene expression data may not be useful until it is well organized. Therefore a classification method is necessary to find the characteristics of gene data acquired from the gene expression. In the proposed method, a set of gene data is extracted according to the fisher's criterion, because we assume that selected gene data is the well-classified data sample. However, the selected gene data does not guarantee well-classified data sample and we calculate feature values using membership function to reduce the influence of outliers in gene data. Feature vectors estimated from the selected feature values are used to train back propagation neural network. The experimental results show that the clustering performance of the proposed method has been improved compared to other existing methods in various gene expression data.

• Journal of Microbiology
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• v.44 no.1
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• pp.64-71
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• 2006

To investigate the effects of the nucleotide sequences in Shine-Dalgarno (SD) and the spacer region (SD-ATG) on bovine growth hormone (bGH) gene expression, the expression vectors under the control of the T7 promoter (pT7-7 vector) were constructed using bGH derivatives (bGH1 & bGH14) which have different 5'-coding regions and were induced in E. coli BL21 (DE3). Oligonucleotides containing random SD sequences and a spacer region were chemically synthesized and the distance between the SD region and the initiation codon were fixed to nine bases in length. The oligonucleotides were annealed and fused to the bGH1 and bGH14 cDNA, respectively. When the bGH gene was induced with IPTG in E. coli BL21(DE3), some clones containing only bGH14 cDNA produced considerable levels of bGH in the range of $6.9\%\;to\;8.5\%$ of total cell proteins by SDS-PAGE and Western blot. Otherwise, the bGH was not detected in any clones with bGH1 cDNA. Accordingly, the nucleotide sequences of SD and the spacer region affect on bGH expression indicates that the sequences sufficiently destabilize the mRNA secondary structure of the bGH14 gene. When the free energy was calculated from the transcription initiation site to the +51 nucleotide of bGH cDNA using a program of nucleic acid folding and hybridization prediction, the constructs with values below -26.3 kcal/mole (toward minus direction) were not expressed. The constructs with the original sequence of bGH cDNA also did not show any expression, regardless of the free energy values. Thus, the disruption of the mRNA secondary structure may be a major factor regulating bGH expression in the translation initiation process. Accordingly, the first stem-loop among two secondary structures present in the 5'-end region of the bGH gene should be disrupted for the effective expression of bGH.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.219-229
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• 2020

Objective: Considering the physiological and clinical importance of leptin receptor (LEPR) in regulating obesity and the fact that porcine LEPR expression is not known to be controlled by lncRNAs and miRNAs, we aim to characterize this gene as a potential target of SSC-miR-323 and the lncRNA TCONS_00010987. Methods: Bioinformatics analyses revealed that lncRNA TCONS_00010987 and LEPR have SSC-miR-323-binding sites and that LEPR might be a target of lncRNA TCONS_00010987 based on cis prediction. Wild-type and mutant TCONS_00010987-target sequence fragments and wild-type and mutant LEPR 3'-UTR fragments were generated and cloned into pmiRRB-REPORT^TM-Control vectors to construct respective recombinant plasmids. HEK293T cells were co-transfected with the SSC-miR-323 mimics or a negative control with constructs harboring the corresponding binding sites and relative luciferase activities were determined. Tissue expression patterns of lncRNA TCONS_00010987, SSC-miR-323, and LEPR in Anqing six-end-white (AQ, the obese breed) and Large White (LW, the lean breed) pigs were detected by real-time quantitative polymerase chain reaction; backfat expression of LEPR protein was detected by western blotting. Results: Target gene fragments were successfully cloned, and the four recombinant vectors were constructed. Compared to the negative control, SSC-miR-323 mimics significantly inhibited luciferase activity from the wild-type TCONS_00010987-target sequence and wild-type LEPR-3'-UTR (p<0.01 for both) but not from the mutant TCONS_00010987-target sequence and mutant LEPR-3'-UTR (p>0.05 for both). Backfat expression levels of TCONS_00010987 and LEPR in AQ pigs were significantly higher than those in LW pigs (p<0.01), whereas levels of SSC-miR-323 in AQ pigs were significantly lower than those in LW pigs (p<0.05). LEPR protein levels in the backfat tissues of AQ pigs were markedly higher than those in LW pigs (p<0.01). Conclusion: LEPR is a potential target of SSC-miR-323, and TCONS_00010987 might act as a sponge for SSC-miR-323 to regulate LEPR expression.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6165-6171
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• 2013

This study aimed to analyze the expression and clinical significance of cyclin G2 (CCNG2) in thyroid carcinoma and the biological effects of CCNG2 overexpression in a cell line. Immunohistochemistry and Western blotting were used to analyze CCNG2 protein expression in 63 cases of thyroid cancer and normal tissues to allow the relationship with clinical factors to be assessed. CCNG2 lentiviral and empty vectors were transfected into the thyroid cancer K1 cell line. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were applied to detect the mRNA and protein levels of CCNG2. MTT assay and cell cycle were also conducted to assess the influence of up-regulated expression of CCNG2 on K1 cell biology. The level of CCNG2 protein expression was found to be significantly lower in thyroid cancer tissue than normal tissues (P<0.05). Western blot: The relative amount of CCNG2 protein in thyroid cancer tissue was respectively found to be significantly lower than in normal tissues (P<0.05), correlating with lymph node metastasis, clinic stage and histological grade (P<0.05), but not gender, age or tumor size (P>0.05). Loss of CCNG2 expression correlated significantly with poor overall survival time on Kaplan-Meier analysis (P<0.05). The results for biological functions showed that K1 cell transfected CCNG2 had a lower survival fraction, a greater percentage in the G0/G1 phases, and lower cyclin-dependent kinase 2 (CDK2) protein expression compared with K1 cells non-transfected with CCNG2 (P<0.05). CCNG2 expression decreased in thyroid cancer and correlated significantly lymph node metastasis, clinic stage, histological grade and poor overall survival, suggesting that CCNG2 may play important roles as a negative regulator in thyroid cancer K1 cells by promoting degradation of CDK2.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.245-252
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• 2001

Erm proteins, MLS (macrolide-lincosamide-streptogramin B) resistance factor proteins, show high degree of amino acid sequence homology and comprise of a group of structurally homologous N-methyltransferases. On the basis of the recently determined structures of ErmC` and ErmAM, ErmSF was divided into two domains, N-terminal end catalytic domain and C-terminal end substrate binding domain and attempted to overexpress catalytic domain in E. coli using various pET expression systems. Three DNA fragments were used to express the catalytic domain: DNA fragment 1 encoding Met 1 through Glu 186, DNA fragment 2 encoding Arg 60 to Glu 186 and DNA fragment 3 encoding Arg 60 through Arg 240. Among the pET expression vectors used, pET 19b successfully expressed the DNA fragment 3 and pET23b succeeded in expression of DNA fragment 1 and 2. But the overexpressed catalytic domains existed as inclusion body, a insoluble aggregate. To assist the soluble expression of ErmSF catalytic domains, Coexpression of chaperone GroESL or Thioredoxin and lowering the incubation temperature to $22^{\circ}C$ were attempted, as did in the soluble expression of the whole ErmSF protein. Both strategies did not seem to be helpful. Solubilization with guanidine-HCl and renaturation with gradual removal of denaturant and partial digestion of overexpressed whole ErmSF protein (expressed to the level of 126 mg/ι culture as a soluble protein) with proteinase K, nonspecific proteinase are under way.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.355-366
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• 2003

A unified procedure for principal component regression (PCR), partial least squares (PLS) and ordinary least squares (OLS) is proposed. The process gives solutions for PCR, PLS and OLS in a unified and non-iterative way. This enables us to see the interrelationships among the three regression coefficient vectors, and it is seen that the so-called E-matrix in the solution expression plays the key role in differentiating the methods. In addition to setting out the procedure, the paper also supplies a robust numerical algorithm for its implementation, which is used to show how the procedure performs on a real world data set.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.779-781
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• 2001

Human leptin is a 16kDa protein and is known to influence body weight control. It is composed of 146 amino acids. In this study, human leptin gene was obtained from homosapiens leptin mRNA using RT-PCR. And leptin gene was inserted into secretion vectors and Saccharomyces cerevisiae was transformed. In flask culture, Saccharomyces cerevisiae transformant showing high leptin expression titre was selected and with the best transformant, fed-batch fermentation and purification was optimized. As a result, about 2 g/L of leptin was expressed and the yield of purification was about 80%.

• BMB Reports
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• v.44 no.10
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• pp.692-697
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• 2011

To investigate the pathways of oxidoreductases in plants, 2 key components in thioredox systems i.e. thioredoxin h (Trx h) and NADPH-dependent thioredoxin reductase (NTR) genes were first isolated from tomatoes (Solanum lycopersicum). Subsequently, the coding sequences of Trx h and NTR were inserted into pET expression vectors, and overexpressed in Escherichia coli. In the UV-Visible spectra of the purified proteins, tomato Trx h was shown to have a characteristic 'shoulder' at ~290 nm, while the NTR protein had the 3 typical peaks unique to flavoenzymes. The activities of both proteins were demonstrated by following insulin reduction, as well as DTNB reduction. Moreover, both NADPH and NADH could serve as substrates in the NTR reduction system, but the catalytic efficiency of NTR with NADPH was 2500-fold higher than with NADH. Additionally, our results reveal that the tomato Trx system might be involved in oxidative stress, but not in cold damage.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.119-119
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• 2003

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2001.12a
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• pp.203-207
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• 2001

In this Paper, we propose the neural network based emotion recognition method for intelligently recognizing the human's emotion using CCD color image. To do this, we first acquire the color image from the CCD camera, and then propose the method for recognizing the expression to be represented the structural correlation of man's feature Points(eyebrows, eye, nose, mouse) It is central technology that the Process of extract, separate and recognize correct data in the image. for representation is expressed by structural corelation of human's feature Points In the Proposed method, human's emotion is divided into four emotion (surprise, anger, happiness, sadness). Had separated complexion area using color-difference of color space by method that have separated background and human's face toughly to change such as external illumination in this paper. For this, we propose an algorithm to extract four feature Points from the face image acquired by the color CCD camera and find normalization face picture and some feature vectors from those. And then we apply back-prapagation algorithm to the secondary feature vector. Finally, we show the Practical application possibility of the proposed method.