• Molecular & Cellular Toxicology
• /
• 제1권2호
• /
• pp.92-98
• /
• 2005

DNA microarray analysis of gene expression in toxicogenomics typically requires relatively large amounts of total RNA. This limits the use of DNA microarray when the sample available is small. To confront this limitation, different methods of linear RNA amplification that generate antisense RNA (aRNA) have been optimized for microarray use. The target preparation strategy using amplified RNA in DNA microarray protocol can be divided into direct-incorporation labeling which resulted in cDNA targets (Cy-dye labeled cDNA from aRNA) and indirect-labeling which resulted in cRNA targets (i.e. Cy-dye labeled aRNA), respectively. However, despite the common use of amplified targets (cDNA or cRNA) from aRNAs, no systemic assessment for the use of amplified targets and bias in terms of hybridization performance has been reported. In this investigation, we have compared the hybridization performance of cRNA targets with cDNA targets from aRNA on a 10 K cDNA microarrays. Under optimized hybridization conditions, we found that 43% of outliers from cDNA technique and 86% from the outlier genes were reproducibly detected by both targets hybridization onto cDNA microarray. This suggests that the cRNA labeling method may have a reduced capacity for detecting the differential gene expression when compared to the cDNA target preparation. However, further validation of this discordant result should be pursued to determine which techniques possesses better accuracy in identifying truly differential genes.

• 한국정보과학회논문지:소프트웨어및응용
• /
• 제35권6호
• /
• pp.347-356
• /
• 2008

마이크로어레이는 분자 생물학 실험에 있어 중요한 도구로 사용되고 있으며, 마이크로어레이 데이타 분석을 위한 다양한 계산학적 방법이 개발되어 왔다. 그러나, 기존 분석방법은 주어진 조건에 영향을 주는 개별 유전자를 추출하는 데 강한 방면, 유전자 간의 복합작용에 의한 영향을 분석하기 힘들다는 단점을 가지고 있다. 하이퍼망 모델은 생물학적인 네트워크 작용을 모방한 구조이며, 계산과정에서 요소간의 복합작용을 직접 고려하기 때문에 기존 방법에서 다루기 힘들었던 요소간 상호작용 분석이 가능하다는 장점을 가진다. 본 논문에서는 마이크로어레이 데이타를 기반으로 microRNA(miRNA) 프로파일 분석을 위한 하이퍼망 분류 기법을 소개한다. 하이퍼망 분류기는 miRNA 쌍을 기본 요소로 하여 진화 과정을 통해 miRNA 분류 데이타를 학습한다. 학습된 하이퍼망으로부터 유의하다.고 판단되는 miRNA 모듈을 쉽게 추출할 수 있으며, 사용자는 추출된 모듈의 유치미성을 직접 판단할 수 있다. 하이퍼망 분류기는 암 관련 miRNA 발현 데이타 분류 실험을 통해 91.46%의 정확도를 보임으로써 기존 기계학습 방법에 비해 뛰어난 성능을 보여주었으며, 하이퍼망 분석을 통해 생물학적으로 유의한 miRNA 모듈을 찾을 수 있음을 확인하였다.

• Reproductive and Developmental Biology
• /
• 제32권4호
• /
• pp.229-235
• /
• 2008

Silencing of Dicer1 by siRNA did not inhibit development up to the blastocyst stage, but decreased expression of selected transcription factors, including Oct-4, Sox2 and Nanog, suggesting that Dicer1 gene expression is associated with differentiation processes at the blastocyst stage (Cui et al., 2007). In order to get insights into genes which may be linked with microRNA system, we compared gene expression profiles in Gapdh and Dicer1 siRNA-microinjected blastocysts using the Applied Biosystem microarray technology. Our data showed that 397 and 737 out of 16354 genes were up- and down-regulated, respectively, following siRNA microinjection (p<0.05), including 24 up- and 28 down-regulated transcription factors. Identification of genes that are preferentially expressed at particular Dicer1 knock down embryos provides insights into the complex gene regulatory networks that drive differentiation processes in embryos at blastocyst stage.

• 한국환경과학회지
• /
• 제24권5호
• /
• pp.623-631
• /
• 2015

Microarray technology provides a unique tool for the determination of gene expression at the level of messenger RNA (mRNA). This study, the mRNA expression profiles provide insight into the mechanism of action of cadmium in Fleshy shrimp (Fenneropenaeus chinensis). The ability of genomic technologies was contributed decisively to development of new molecular biomarkers and to the determination of new possible gene targets. Also, it can be approach for monitoring of trace metal using oligo-chip microarray-based in potential model marine user level organisms. 15K oligo-chip for F. chinensis that include mostly unique sets of genes from cDNA sequences was developed. A total of 13,971 spots (1,181 mRNAs up- regulated and 996 down regulated) were identified to be significantly expressed on microarray by hierarchical clustering of genes after exposure to cadmium for different conditions (Cd24-5000 and Cd48-1000). Most of the changes of mRNA expression were observed at the long time and low concentration exposure of Cd48-1000. But, gene ontology analysis (GO annotation) were no significant different between experiments groups. It was observed that mRNA expression of main genes involved in metabolism, cell component, molecular binding and catalytic function. It was suggested that cadmium inhibited metabolism and growth of F. chinensis.

• Molecules and Cells
• /
• 제40권10호
• /
• pp.714-730
• /
• 2017

Pre-mRNA splicing further increases protein diversity acquired through evolution. The underlying driving forces for this phenomenon are unknown, especially in terms of gene expression. A rice alternatively spliced transcript detection microarray (ASDM) and RNA sequencing (RNA-Seq) were applied to differentiate the transcriptome of 4 representative organs of Oryza sativa L. cv. Ilmi: leaves, roots, 1-cm-stage panicles and young seeds at 21 days after pollination. Comparison of data obtained by microarray and RNA-Seq showed a bell-shaped distribution and a co-lineation for highly expressed genes. Transcripts were classified according to the degree of organ enrichment using a coefficient value (CV, the ratio of the standard deviation to the mean values): highly variable (CVI), variable (CVII), and constitutive (CVIII) groups. A higher index of the portion of loci with alternatively spliced transcripts in a group (IAST) value was observed for the constitutive group. Genes of the highly variable group showed the characteristics of the examined organs, and alternatively spliced transcripts tended to exhibit the same organ specificity or less organ preferences, with avoidance of 'organ distinctness'. In addition, within a locus, a tendency of higher expression was found for transcripts with a longer coding sequence (CDS), and a spliced intron was the most commonly found type of alternative splicing for an extended CDS. Thus, pre-mRNA splicing might have evolved to retain maximum functionality in terms of organ preference and multiplicity.

• Bulletin of the Korean Chemical Society
• /
• 제29권6호
• /
• pp.1137-1140
• /
• 2008

M1 RNA, the catalytic subunit of Escherichia coli RNase P, is an essential ribozyme that processes the 5' leader sequence of tRNA precursors (ptRNAs). Using KS2003, an E. coli strain generating only low levels of M1 RNA, which showed growth defects, we examined whether M1 RNA is involved in polycistronic mRNA processing or degradation. Microarray analysis of total RNA from KS2003 revealed six polycistronic operon mRNAs (acpP-fabF, cysDNC, flgAMN, lepAB, phoPQ, and puuCBE) showing large differences in expression between the adjacent genes in the same mRNA transcript compared with the KS2001 wild type strain. Model substrates spanning an adjacent pair of genes for each polycistronic mRNA were tested for RNase P cleavage in vitro. Five model RNAs (cysNC, flgMN, lepAB, phoPQ, and puuBE) were cleaved by RNase P holoenzyme but not by M1 RNA alone. However, the cleavages occurred at non-ptRNA-like cleavage sites, with much less efficiency than the cleavage of ptRNA. Since cleavage products generated by RNase P from a polycistronic mRNA can have different in vivo stabilities, our results suggest that RNase P cleavage may lead to differential expression of each cistron.

• Journal of Animal Science and Technology
• /
• 제52권4호
• /
• pp.329-336
• /
• 2010

본 연구는 소의 부위별 근육에 특이하게 발현하는 유전자 마커를 발굴하여 소고기의 부위를 과학적으로 판명할 수 있는 기술을 개발하고자 실시하였다. 이러한 연구 목표 아래 먼저 사태(Beef shank), 등심(Longissimus dorsi), 양지(Deep pectoral), 홍두깨(Semitendinosus) 부위의 근육조직에서 MSC (myogenic satellite cell, 근육줄기세포)를 순수 분리하고 이를 MFC (myotube-formed cell; 근관이 형성된 세포)로 분화시키거나 ALC (adipocyte-like cell; 지방세포와 유사한 세포)로 이형분화 시킨 후 3가지의 세포로 부터 각각의 RNA를 추출하였다. 이렇게 추출한 RNA는 24,000개의 bovine oligo-nucelotide (70 mer)가 집적된 microarray를 이용해 4개의 조직 중 1개의 조직에서만 MSC의 분화(MFC) 또는 이형분화 과정에서 mRNA의 발현이 증감을 보이는 유전자 135개를 먼저 발굴하였다. 135개의 유전자에 대해 microarray 분석에 사용한 동일한 RNA를 이용하여 real-time PCR 기술로 검증한 결과 총 29개의 유전자가 microarray 분석 결과와 유사함을 보였다. 29개의 유전자를 다시 4개 부위의 생체 조직에서 추출한 RNA를 이용해 real-time PCR 방법으로 분석한 결과 TS (thymi- dlyate synthase), TE (tropoelastin), RAD52(similar RAD52 motifcontaining protein 1), unknown gene), MLC2 (myosin light 2, regulatory cardiac, slow), TXNIP (thioredoxin-interating protein) 6개의 유전자만이 다른 부위에 비해 사태 부위에서 현저한 발현의 차이를 나타냈다. 결론적으로 본 연구를 통해 소 부위별 근육을 구분할 수 있는 과학적 기술의 토대를 확립하였다.

• 한국발생생물학회:학술대회논문집
• /
• 한국발생생물학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
• /
• pp.109-109
• /
• 2005

• 한국수정란이식학회:학술대회논문집
• /
• 한국수정란이식학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
• /
• pp.109-109
• /
• 2005

• 한국생물정보학회:학술대회논문집
• /
• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
• /
• pp.366-370
• /
• 2005

Tissue microarry is one of the high throughput technologies in the post-genomic era. Using tissue microarray, the researchers are able to investigate large amount of gene expressions at the level of DNA, RNA, and protein The important aspect of tissue microarry is its ability to assess a lot of biomarkers which have been used in clinical practice. To manipulate the categorical data of tissue microarray, we applied Bayesian network classifier algorithm. We identified that Bayesian network classifier algorithm could analyze tissue microarray data and integrating prior knowledge about gastric cancer could achieve better performance result. The results showed that relevant integration of prior knowledge promote the prediction accuracy of survival status of the immunohistochemical tissue microarray data of 18 tumor suppressor genes. In conclusion, the application of Bayesian network classifier seemed appropriate for the analysis of the tissue microarray data with clinical information.