• Molecular & Cellular Toxicology
• /
• 제5권4호
• /
• pp.335-345
• /
• 2009

A major source of paeoniflorin (PF) which was from the Paeonia lactiflora root, has been used as a herbal medicine in East Asia for its antiallergic, antiinflammatory, and immunoregulatory effects. However, only few details are known about the mechanism of apoptosis induced by this compound. The present study was undertaken to further elucidate the molecular mechanism of apoptosis and the changes of gene expression elicited by PF using DNA microarrays and computational gene-expression analysis tools in human leukemia U937 cells. A comparative global transcription analysis between treatment with PF and anisomycin (AM) that induces apoptosis in U937 cells revealed that c-Jun-$NH_2$-kinase (JNK) pathway related genes were less expressed in PF-treated cells. Elucidation of the mechanisms by which PF conducts its anti-cancer activities through comparative analysis of the gene expression is necessary to provide a solid foundation for its use as a promising agent in prevention and treatment strategies.

• Journal of Microbiology and Biotechnology
• /
• 제18권5호
• /
• pp.837-844
• /
• 2008

Glucose (xylose) isomerases from Streptomyces sp. have been used for the production of high fructose corn syrup for industrial purposes. An 11-kb DNA fragment containing the xyl gene cluster was isolated from Streptomyces lividans TK24 and its nucleotide sequences were analyzed. It was found that the xyl gene cluster contained a putative transcriptional repressor (xylR), xylulokinase (xylB), and xylose isomerase (xylA) genes. The transcriptional directions of the xylB and xylA genes were divergent, which is consistent to those found in other streptomycetes. A gene encoding XylR was located downstream of the xylB gene in the same direction, and its mutant strain produced xylose isomerase regardless of xylose in the media. The enzyme expression level in the mutant was 4.6 times higher than that in the parent strain under xylose-induced condition. Even in the absence of xylose, the mutant strain produce over 60% of enzyme compared with the xylose-induced condition. Gel mobility shift assay showed that XylR was able to bind to the putative xyl promoter, and its binding was inhibited by the addition of xylose in vitro. This result suggested that XylR acts as a repressor in the S. lividans xylose operon.

• 한국미생물·생명공학회지
• /
• 제23권2호
• /
• pp.131-137
• /
• 1995

The alkaline phosphatase (K-ALPase) gene of Kluyveromyces fragilis has been cloned (1) and determined its base sequences (2) previously in our laboratory. When the K-ALPase gene was expressed in Escherichia coli and Saccharomyces cerevisiae, it showed a constitutive activity in E. coli, and a derepressed activity in S. cerevisiae in phosphate-limited medium. Northem hybridization experiment was performed to elucidate the transcription level of the K-ALPase gene. Northern experiment showed that transcription level of K-ALPase gene in S. cerevisiae was higher in phosphate depletion, but it was higher in high phosphate medium than in phosphate limited medium in K. fragilis. The transcription initiation site of the K-ALPase gene was determined by primer extension analysis. It matched nucleotide position - 169 in relation to the putative trnslational start site.

• KSBB Journal
• /
• 제8권2호
• /
• pp.104-109
• /
• 1993

한 개의 pladsmid에 Gus gene과 Hygromycin resistant gene(Hpt)을 합친 vector를 개발하였다. 이 재조합된 DNA를 벼의 건조한 종자에 imbibition시켜 형질전환했을 때, hygromycin 배지에서 선별한 결과 그 발현율은 single Hpt vector와 차이 가 없었으며, 주로 뿌리의 생장점이나 자엽초에서 Gus expression을 볼 수 있였다. 또한 hygromycin 배지에서 선별되어 성체가 된 개체에서 그 genomic DNA를 뽑아 PCR을 한 결과 1Kb Hpt gene을 확인하였다. 그리고 생체에서 추출한 총 RNA에서 cDNA를 만든 후 reverse transcription PCR을 통하여, 외부 유전자의 발현을 증명하였다.

• Molecular & Cellular Toxicology
• /
• 제1권4호
• /
• pp.281-283
• /
• 2005

Extraction of biologically meaningful data and their validation are very important for toxicogenomics study because it deals with huge amount of heterogeneous data. BINGO is an annotation mining tool for biological interpretation of gene groups. Several statistical modeling approaches using Gene Ontology (GO) have been employed in many programs for that purpose. The statistical methodologies are useful in investigating the most significant GO attributes in a gene group, but the coherence of the resultant GO attributes over the entire group is rarely assessed. BINGO complements the statistical methods with graph-theoretic measures using the GO directed acyclic graph (DAG) structure. In addition, BINGO visualizes the consistency of a gene group more intuitively with a group-based GO subgraph. The input group can be any interesting list of genes or gene products regardless of its generation process if the group is built under a functional congruency hypothesis such as gene clusters from DNA microarray analysis.

• Macromolecular Research
• /
• 제15권2호
• /
• pp.100-108
• /
• 2007

Gene therapy has become a promising strategy for the treatment of genetically based diseases, such as cancer, which are currently considered incurable. A major obstacle in the field of cancer gene therapy is the development of a safe and efficient delivery system for therapeutic gene transfer. Non-viral vectors have attracted great interest, as they are simple to prepare, stable, easy to modify and relatively safe compared to viral vectors. In this review, an insight into the strategies developed for polyethylenimine (PEI)-based non-viral vectors has been provide, including improvement of the polyplex properties by incorporating hydrophilic spacer, poly(ethylene glycol) (PEG). Moreover, this review will summarize the strategies for the tumor targeting. Specifically, a targeted polymeric gene delivery system, PEI-g-PEG-RGD, will be introduced as an efficient gene delivery vector for tumor therapy, including its functional analysis both in vitro and in vivo.

• Animal cells and systems
• /
• 제7권2호
• /
• pp.159-164
• /
• 2003

The RAD3 gene of Saccharomyces cerevisiae is required for excision repair and is essential for cell viability. The RAD3 encoded protein possesses a single stranded DNA-dependent ATPase and DNA and DNA-RNA helicase activities. To examine the extent of conservation of structure and function of a S. pombe RAD3 during eukaryotic evolution, the RAD3 homolog gene was isolated by screening of genomic DNA library. The isolated gene was designated as HRD3 (homolog of RAD3 gene). Southern blot analysis confirmed that S. pombe chromosome contains the same DNA as HRD3 gene and this gene exists as a single copy in S. pombe. The transcript of 2.8 kb was detected by Northern blot analysis, The level of transcripts increased by ultraviolet (UV) irradiation, indicating that HRD3 is one of the UV-inducible genes in S. pombe. Furthermore, the predicted partial sequence of HRD3 protein has 60％ identity to S. cerevisiae RAD3 gene. This homology was particularly striking in the regions identified as being conserved in a group of DNA helicases. Gene deletion experiments indicate that the HRD3 gene is essential for viability and DNA repair function. These observations suggest evolutionary conservation of other protein components with which HRD3 might interact in mediating its DNA repair and viability functions.

• The Plant Pathology Journal
• /
• 제25권4호
• /
• pp.344-351
• /
• 2009

A biocontrol bacterium Bacillus licheniformis N1 grown in nutrient broth showed no chitinolytic activity, while its genome contains a gene which encodes a chitinase. The gene for chitinase from B. licheniformis N1 was amplified by PCR and the deduced amino acid sequence analysis revealed that the chitinase exhibited over 95% identity with chitinases from other B. licheniformis strains. Escherichia coli cells carrying the recombinant plasmid displayed chitinase activity as revealed by the formation of a clear zone on chitin containing media, indicating that the gene could be expressed in E. coli cells. Chitinase gene expression in B. licheniformis N1 was not detected by RT-PCR analysis. The protein was over-expressed in E. coli BL21 (DE3) as a glutathione S-transferase fusion protein. The protein could also be produced in B. subtilis 168 strain carrying the chitinase gene of N1 strain. The crude protein extract from E. coli BL21 carrying GST fusion protein or culture supernatant of B. subtilis carrying the chitinase gene exhibited enzyme activity by hydrolyzing chitin analogs, 4-methylumbelliferyl-$\beta$-D-N,N'-diacetylchitobioside and 4-methylumbelliferyl-$\beta$-D-N,N',N"-triacetylchitotrioside. These results indicated that even though the chitinase gene is not expressed in the N1 strain, the coding region is functional and encodes an active chitinase enzyme. Furthermore, B. subtilis 168 transformants expressing the chitinase gene exhibited antifungal activity against Fulvia fulva by suppressing spore germination. Our results suggest that the proper engineering of the expression of the indigenous chitinase gene, which will lead to its expression in the biocontrol strain B. licheniformis N1, may further enhance its biocontrol activity.

• 한국육종학회지
• /
• 제42권1호
• /
• pp.50-55
• /
• 2010

옥수수 R 유전자의 대립인자 중 하나인 R-r:standard (R-r:std)는 종자 호분층의 안토시아닌 합성을 조절하는 S subcomplex와 종자 이외 식물체부위의 안토시아닌 합성을 조절하는 P component로 구성되어 있으며, S subcomplex는 S1 및 S2 component로 구성되어 있다. R 유전자의 대립인자 중 일부는 Pl 유전자가 존재할 경우 종피의 안토시아닌 합성을 유도한다. 따라서 Pl 유전자가 존재할 경우 옥수수 종피의 안토시아닌 합성을 유도하는 R 유전자의 구성요소를 구명하고자 종피의 안토시아닌 합성에 미치는 서로 다른 R 인자들의 효과를 분석하였다. R-ch와 r-ch 인자는 유사한 정도의 착색 효과를 보였으며, R-r:Ecuador (R-r:Ec)는 이들보다 짙은 착색효과를 나타내었다. S subcomplex의 기능은 상실하였으나 정상적인 P component를 보유하고 있는 것으로 추정되는 r-ch는 Pl 유전자가 존재할 경우 종피의 색소합성 기능을 유지하고 있으나, S subcomplex의 기능은 정상이나 P component의 기능은 잃어버린 것으로 추정되는 R-r:Ec 유래 인자 R-g:g1111는 Pl 유전자가 존재할 경우에도 종피가 착색되지 않았다. 더욱이 R-ch와 r-ch 인자의 PCR 분석 결과, R-ch는 P와 S1 component를 보유하고 있으나, r-ch는 S1을 보유하고 있지 않는 것으로 나타났다. 따라서 R 유전자의 구성요소 중 P component가 종피의 안토시아닌 합성에 관여하는 구성요소로 추정되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권11호
• /
• pp.1515-1520
• /
• 2012

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is important for regulation of growth and development in mammals. The present investigation was carried out to study DNA polymorphism by PCR-RFLP of IGFBP-3 gene and its effect on fibre traits of Chinese Inner Mongolian cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Four hundred and forty-four animals were used to detect polymorphisms in the hircine IGFBP-3 gene. A 316-bp fragment of the IGFBP-3 gene in exon 2 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in the populations. The frequency of AA, AB and BB genotypes was 0.58, 0.33 and 0.09 respectively. The allelic frequency of the A and B allele was 0.75 and 0.25 respectively. Nucleotide sequencing revealed a C>G transition in the exon 2 region of the IGFBP-3 gene resulting in R158G change which caused the polymorphism. Least squares analysis revealed a significant effect of genotypes on cashmere weight (p<0.0001), cashmere fibre length (p<0.001) and hair length (p<0.05) of the animals. The effect of genotypes on cashmere fibre diameter was not statistically significant (p>0.05). The animals of AB and BB genotypes showed higher cashmere weight, cashmere fibre length and hair length than the animals possessing AA genotype. These results suggested that polymorphisms in the hircine IGFBP-3 gene might be a potential molecular marker for cashmere weight in cashmere goats.