• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
• /
• pp.1-15
• /
• 1999

In a case-control study to evaluate the factors involved in the development of hepatocellular carcinoma, polymorphisms of the p53 gene were compared in 68 cases mostly infected with hepatitis C virus (HCV) and 68 controls matched for sex and age: DNA from peripheral blood leukocytes was analyzed by the polymerase chain reaction-single strand conformation polymorphism method and direct sequencing. Polymorphisms analyzed were those in exon 4 (CCC vs. CGC, Pro vs. Arg at codon 72, Al allele vs. A2 allele), intron 2 (C vs. G at nucleotide 38, Al vs. A2), intron 3 (C vs. A at nucleotide 65, Al vs. A2; absence and presence of 16 base pair repeat at nucleotides 24 to 39, Al vs. A2), intron 6 (A vs. G at nucleotide 62, Al vs. A2) and intron 7 (C and T vs. T and G at nucleotides 72 and 92, Al vs. A2). A significantly higher frequency of the allele for CCC (Pro, Al) at codon 72 of exon 4 was found in cases (39%) than in controls (26%) (p<0.05). Highly significant linkage of the polymorphisms in exon 4, intron 2, intron 3 and intron 7, and between the intron 3-16 bp duplication and polymorphism in intron 6 also was found. Matched Fair analysis showed significantly higher frequencies of certain haplotypes (1-1-1-1-2-2 or 1-1-2-1-2-1 for exon 4, intron 2, intron 3, the intron 3-16 bp duplication, intron 6 and intron 7) in cases than in controls (p=0.014, OR=2.27, 95% CI= 1.08-5.12). No preference of specific p53 polymorphisms for specific HCV genotype was detected. These findings suggest that in hepatocarcinogenesis mainly due to HCV infection, genetic factors may be involved and that genetic markers can serve as predictors of a high-risk group for hepatocarcinogenesis.

• Genomics & Informatics
• /
• 제10권1호
• /
• pp.58-64
• /
• 2012

Intron prediction is an important problem of the constantly updated genome annotation. Using two model plant (rice and $Arabidopsis$) genomes, we compared two well-known intron prediction tools: the Blast-Like Alignment Tool (BLAT) and Sim4cc. The results showed that each of the tools had its own advantages and disadvantages. BLAT predicted more than 99% introns of whole genomic introns with a small number of false-positive introns. Sim4cc was successful at finding the correct introns with a false-negative rate of 1.02% to 4.85%, and it needed a longer run time than BLAT. Further, we evaluated the intron information of 10 complete plant genomes. As non-coding sequences, intron lengths are not limited by a triplet codon frame; so, intron lengths have three phases: a multiple of three bases (3n), a multiple of three bases plus one (3n + 1), and a multiple of three bases plus two (3n + 2). It was widely accepted that the percentages of the 3n, 3n + 1, and 3n + 2 introns were quite similar in genomes. Our studies showed that 80% (8/10) of species were similar in terms of the number of three phases. The percentages of 3n introns in $Ostreococcus$ $lucimarinus$ was excessive (47.7%), while in $Ostreococcus$ $tauri$, it was deficient (29.1%). This discrepancy could have been the result of errors in intron prediction. It is suggested that a three-phase evaluation is a fast and effective method of detecting intron annotation problems.

• Genomics & Informatics
• /
• 제6권2호
• /
• pp.84-86
• /
• 2008

The Tetrahymena group I intron has been shown to employ a trans-splicing reaction and has been modified to specifically target and replace human telomerase reverse transcriptase (hTERT) RNA with a suicide gene transcript, resulting in the induction of selective cytotoxicity in cancer cells that express the target RNA, in animal models as well as in cell cultures. In this study, we evaluated the target RNA specificity of trans-splicing phenomena by the group I intron in mice that were intraperitoneally inoculated with hTERT-expressing human cancer cells to validate the anti-cancer therapeutic applicability of the group I intron. To this end, an adenoviral vector that encoded for the hTERT-targeting group I intron was constructed and systemically injected into the animal. 5'-end RACE-PCR and sequencing analyses of the trans-spliced cDNA clones revealed that all of the analyzed products in the tumor tissue of the virus-infected mice resulted from reactions that were generated only with the targeted hTERT RNA. This study implies the in vivo target specificity of the trans-splicing group I intron and hence suggests that RNA replacement via a trans-splicing reaction by the group I intron is a potent anti-cancer genetic approach.

• The Plant Pathology Journal
• /
• 제29권3호
• /
• pp.234-241
• /
• 2013

Polygalacturonase (PG) gene is a typical gene family present in eukaryotes. Forty-nine PGs were mined from the genomes of Neurospora crassa and five Aspergillus species. The PGs were classified into 3 clades such as clade 1 for rhamno-PGs, clade 2 for exo-PGs and clade 3 for exo- and endo-PGs, which were further grouped into 13 sub-clades based on the polypeptide sequence similarity. In gene structure analysis, a total of 124 introns were present in 44 genes and five genes lacked introns to give an average of 2.5 introns per gene. Intron phase distribution was 64.5% for phase 0, 21.8% for phase 1, and 13.7% for phase 2, respectively. The introns varied in their sequences and their lengths ranged from 20 bp to 424 bp with an average of 65.9 bp, which is approximately half the size of introns in other fungal genes. There were 29 homologous intron blocks and 26 of those were sub-clade specific. Intron losses were counted in 18 introns in which no obvious phase preference for intron loss was observed. Eighteen introns were placed at novel positions, which is considerably higher than those of plant PGs. In an evolutionary sense both intron loss and gain must have taken place for shaping the current PGs in these fungi. Together with the small intron size, low conservation of homologous intron blocks and higher number of novel introns, PGs of fungal species seem to have recently undergone highly dynamic evolution.

• 미생물학회지
• /
• 제35권4호
• /
• pp.253-257
• /
• 1999

Cadaverine, putrescine, spermidine과 spermine이 spectinomycin에 의한 T4 파지 thymidylate synthase 유전자(td) intron의 splicing 억제에 미치는 영향을 조사하였다. Polyamine이 존재하지 않는 상태에서 7mM spectinomycin은 splicing rate를 약 40% 감소시켰다. 사용한 농도 범위(0.1~5mM)에서 cadaverine은 splicing rate를 감소시켰으나, putrescine은 0.5mM 농도에서 약 13% 정도의 splicing rate를 증가시켰다. Spermidine은 0.5mM 농도에서 약 11% 정도의 splicing rate를 증가시켰으며, sperimine은 0.01mM 농도에서 약 16% 정도의 splicing rate을 증가시켰다. 시험한 polyamine 중에서 특히 sperimine은 가장 낮은 농도에서 spectinomycin에 의한 억제반응을 극복하는 최고의 활성효과를 나타냈다. 이와 같은 억제 회복 효과는 polyamine에 의한 td intron 리보자임의 구조적 안정성에 기인하는 것으로 추정된다.

• 한국전자통신학회논문지
• /
• 제16권4호
• /
• pp.675-682
• /
• 2021

제한된 종류, 제한된 수량의 센서를 사용하여야 하는 환경에서 다양한 상황정보를 획득하여야 하는 수요가 나타날 수 있다. 본 연구에서는 제한된 숫자의 센서를 사용하여야 하는 환경에서 한정된 센서를 사용하면서도 이전보다 다양한 상황정보를 획득하기 위한 새로운 방안을 제안하였다. 이를 위하여 생물학 분야에서 큰 관심을 얻고 있는 Exon-Intron이론에서 실마리를 얻어 이를 기초로 다양한 상황정보 획득 방안을 제안하였다. Exon-Intron의 선택적 자르기 및 조합 방안과 같이 각 센서의 이벤트들을 효율적으로 자르고 각 이벤트 데이터들을 조합하여 활용함으로써 획득하는 상황정보의 다양화를 실현할 수 있었다.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2003년도 추계학술대회
• /
• pp.87-88
• /
• 2003

PegIntron is the pegylated form of human recombinant interferon alfa-2b (IFN${\alpha}$2b). IFN ${\alpha}$2b, known as Intron A, has been in approved clinical use since the 1980's for various cancer indications, and for the treatment of Hepatitis C. In the mid 1990's, several clinical investigators reported that combination therapy with ribavirin and Intron A dramatically increased the therapeutic efficacy for treatment of Hepatitis C.(omitted)

• BMB Reports
• /
• 제28권1호
• /
• pp.57-61
• /
• 1995

The expression of a recombinant human lactoferrin is reported in mouse HC11 mammary epithelial cells. Expression of human lactoferrin (hLF) was achieved by placing its cDNA under the control of the bovine ${\beta}$-casein gene. To improve the hLF expression level in a cell culture system, two artificial introns were also introduced to construct expression vectors. One intron was a hybrid-splice signal consisting of bovine ${\beta}$-casein intron 1 and rabbit ${\beta}$-globin intron II. The other intron was a DNA fragment spanning intron 8 of the bovine ${\beta}$-casein gene. The hybrid intron moderately elevated hLF expression, whereas intron 8 alone did not express any detectable amount of hLF as judged by Northem and Western blot analyses. When the two introns were used together they contributed to a synergistic elevation of hLF expression. These data indicate that artificial introns on both sides of the hLF cDNA were necessary to increase expression of cDNA.

• 생명과학회지
• /
• 제12권4호
• /
• pp.427-432
• /
• 2002

잇바디돌김(Porptyra dentata)을 대상으로 핵의 18S ribo-somal RNA를 지령하는 유전자 즉 18S rDNA 유전자를 증폭하고, 염기서열분석을 수행하였다. 전체 18S rDNA의 exon 영역 크기는 1822 bp, intron 영역의 크기는 512 bp였다. 이들 exon과 intron 영역의 G+C함량은 각각 49%와 55%씩 나타내었다. 일본산 잇바디돌김(CenBank accession number: AB013183)의 exon 영역과의 비교에서 상동성이 97.1%에 도달하였다. 568번과 569번 염기사이의 upstream에 위치하는 intron 영 역에서는 AB013183과 52.1%의 상동성을 보였다.

• Journal of Plant Biotechnology
• /
• 제40권1호
• /
• pp.27-36
• /
• 2013

We isolated and functionally characterized a Dendrobium Actin1 (DmACT1) promoter that drives strong gene expression in the orchid genus Dendrobium. A genomic fragment containing the region 3227 bp upstream of the coding region of DmACT1 was obtained by inverse PCR. Detailed comparison of the full-length cDNA and genomic sequences revealed that DmACT1 has a 1374 bp first intron in the 5' UTR. However, the 5' flanking sequences upstream of the coding region showed no obvious sequence similarities compared to those of known promoters, including plant actin promoters. Serial deletion constructs of the 5' flanking region from the translation initiation codon were fused to the coding sequence of a GUS/luciferase fusion reporter to identify the regulatory elements necessary for promoter activity. Transient assays in the flowers of Dendrobium revealed that the 5' UTR-intron greatly enhanced promoter activity. Moreover, the DmACT1 promoter with its 5' UTR-intron yielded approximately 10-fold higher reporter activity than the rice Act1 promoter-intron. Our data suggest that the DmACT1 promoter with its 5' UTR-intron is a useful tool for strong expression of transgenes in Dendrobium orchids.