• 한국가축번식학회지
• /
• 제27권3호
• /
• pp.225-231
• /
• 2003

본 연구는 생체 내 세포 및 조직배양기로서의 면역결핍동물을 개발할 목적으로 proximal lck promoter와 DT-A gene를 이용하여 형질전환생쥐을 생산하고 이 형질전환생쥐의 면역세포에서 DT-A gene이 발현되는지를 분석하였다. 형질전환생쥐와 정상생쥐로부터 thymus, spleen 및 liver에서 RNA를 추출하여 RT-PCR수행하였는데 정상생쥐의 조직에서는 어떠한 DT-A gene의 발현양상을 얻을 수 없었으나 형질전환생쥐의 thymus, spleen, liver에 DT gene의 발현을 확인할 수 있었고, Northern blotting을 이용하여 형질전환생쥐의 thymus, spleen 및 liver에서 DT-A gene이 강하게 발현되는 것으로 나타났다. 형질전환생쥐 $F_1$ 및 $F_2$ 산자의 혈액에서 T-cell 발달의 분포도를 확인하기 위해 CD4 및 CD8 antibody를 이용하여 FACS analysis를 실시하였는데 형질전환생쥐의 혈액 내 mature T-cell인 single positive thymocyte의 수가 정상생쥐에 비해 감소하는 경향을 나타냈다. 정상생쥐의 혈액 내 T-cell 중 $CD8^{+}$ T-cell의 경우 약 50%를 나타냈으나 형질전환생쥐의 경우 33%로 감소하였고, $CD4^{+}$ T-cell은 정상생쥐에서 10%를 차지하고 있으나 형질전환생쥐에서는 5.9%로 감소되는 것으로 분석되었다. 그러므로 본 연구의 형질전환생쥐에서 lck promoter에 의해 초기 immature한 상태의 T-cell에서 DT-A gene이 발현되어 발육중인 T-cell이 파괴 되어 mature 상태인 $CD4^{+}CD8^{-}$나 $CD4^{-}CD8^{+}$ cells (single-positive)들이 감소된 것으로 확인되었다.

• Journal of Plant Biotechnology
• /
• 제2권3호
• /
• pp.135-142
• /
• 2000

The activity of promoter sequences was evaluated in garlic cells using the $\beta$-glucuronidase (GUS) gene as a reporter. Histochemical GUS assay indicated transient GUS activity in leaf, callus and root cells 48 hours after particle bombardment transformation. Quantitative fluorometric assays in extracts of transformed leaves demonstrated that the CsVMV promoter induced the highest level of gene expression, which was, on average, ten fold the level induced by CaMV35S and by the Arabidopsis Act2 promoters and two fold the level expression observed with a construct containing a double CaMV35S plus the untranslated leader sequence from AMV. No activity or very low levels were observed when cells were transformed with plasmids rontaining the typical monocot promoters, Actl, from rice or the Ubi-1, from maize. The green fluorescent protein (GFP) was also tested as a marker gene for garlic transformation. Intense fluorescence was observed in leaf, callus and root cells transformed with a construct containing the gfp gene under control of the CaMV35 Promoter. No fluorescence was detected when the gfp was under control of the Ubi-1 promoter.

• Plant Breeding and Biotechnology
• /
• 제2권3호
• /
• pp.289-300
• /
• 2014

A tissue-specific and developmentally expressed gene was isolated from Chinese cabbage (Brassica rapa L. ssp. pekinensis), designated BrREF (B. rapa Rubber elongation factor). BrREF transcripts were expressed at high levels in seedlings and at low levels in flower buds and roots. To study the activity of this promoter, the 2.2 kb upstream sequence of BrREF gene was fused to a β-glucuronidase (GUS) reporter gene and was introduced into Arabidopsis thaliana and B. napus by Agrobacterium-mediated transformation. Strong expression of GUS driven by the BrREF promoter was detected in the cotyledons and hypocotyls of transgenic plant seedlings, but GUS expression was weak in roots, excluding the root tips. GUS expression in the cotyledons and hypocotyls decreased dramatically as the seedlings matured and was not detected in the tissues of mature plants. During floral development, GUS expression was observed in immature anthers. These findings suggest that the BrREF promoter can modulate the tissue-specific and developmental expression of gene at the early stages of growth and development.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제34권5호
• /
• pp.518-524
• /
• 2008

Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

• 생명과학회지
• /
• 제21권10호
• /
• pp.1466-1472
• /
• 2011

본 연구에서는 누에의 초기 배아시기에 유전자 발현 조절이 가능한 EEG-704 promoter를 개발하고자 하였다. Promoter의 핵심 영역을 결정하기 위하여, 10개의 서로 다른 partial mutant clone들을 만들고 이를 Sf9 곤충세포주에 도입하여 luciferase assay 방법을 사용하여 각각의 clone의 활성을 분석하였다. Constitutive promoter인 BmA3 promoter에 의한 활성과 비교하였을 때, 약 1.5 kb의 promoter 염기서열을 포함하는 clone이 가장 높은 luciferase 발현율을 나타내었다. 특히 EEG-704 유전자의 경우 BLAST를 이용한 유전자 비교 분석의 결과 누에의 열충격 단백질20.8 (BmHsp20.8) 과 동일한 것으로 밝혀졌으며, 정상 온도조건과 비교하였을 때 열충격을 가한 조건하에서 발현율이 증가하는 현상을 나타내었다. 특이적으로 발생단계에서 직 간접적으로 발현 조절이 가능한 이러한 promoter는 여러 유용 재조합 단백질 생산을 위한 형질전환 누에 개발 시 매우 유용할 것으로 생각된다.

• KSBB Journal
• /
• 제10권1호
• /
• pp.89-96
• /
• 1995

A rabidopsis thaliana의 trpl 변이 식물체는 uv 하에서 푸른 형광 빛을 발하며, phosphoribosyl anthranilate transferase를 encoding하는 유전자가 결여되어 있다. 이 유전자를 PATl이라고 하며, 많 은 미 생물에서 phospho ribosyl anthranilate trans ferase와 homologous하다. 트럽토판 생합성에서 이 효소가 결여되면 anthranilate가 축적되며 형광 빛 을 발하게 된다. PATl 의 유전자 조절을 알아보기 위하여, PATl 유전자의 promoter를 단계 별로 삭제하여 트립토판 변이 식물체의 형질전환과 재분화를 시도하였다. 이 러한 유전자 조작을 통하여 이 유전자의 발현 양상을 조절하는 promoter 요소와 작용을 확인할 수 있으리라고 생각된다. 또한 PAT의 항체를 사용한 Immunoassay를 통하여 형질전환체 의 단백질 양의 변화를 분석한 결과 PATl의 완전 한 promoter를 가진 pHSI07의 형질전환체는 대조구보다 2배의 단백질 양을 나타냄으로서 2쌍의 PAT 유전자가 발현되었음을 알 수 있었다. PATl 은 selection marker와 reporter 유전자로서 분자유 전학연구에 공헌할 수 였으리라고 생각된다.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제11권3호
• /
• pp.273-276
• /
• 2006

RNA interference (RNAi), a process of sequence-specific gene suppression, has been known as a natural gene regulatory mechanism in a wide range of lower organisms. Recently, we have reported that a transfection of human U6 promoter (hU6) driven hairpin small-interference RNA (siRNA) plasmid specifically knocks down the target gene by post-transcriptional gene silencing in mammalian cells. Here we report that transfection of polymerase chain reaction (PCR) products, containing human U6 promoter with hairpin siRNA, knocks down the target gene expression in human teratocarcinoma NT-2/D1 cells. Moreover, we showed 3' end termination sequence, 5 Ts, is not critical elements for knocking down in PCR-based siRNA system. Therefore, the PCR-based siRNA system is a promising tool not only for the screening but also to temporally regulate gene expression in the human progenitor cells.

• Animal cells and systems
• /
• 제7권1호
• /
• pp.63-68
• /
• 2003

Until recently, interest in human complement receptor type I (CR1) has focused on immune complex processing, which contributed to our understanding of regulatory mechanism of complement activation. However, the promoter structure and transcriptional regulation of human CR1 gene has not been clear. To study the unique regulation of human CR1 gene expression, we assessed promoter activity of the $5^1$-flanking region of human CR1 gene using transient transfection and gel mobility shift assays. In this study we demonstrated that NF-Y binds to the inverted CCAAT element and that the functional interaction with protein(s) which bind to the GC-rich motif may be necessary for optimal transcription of human CR1 gene. We also show that sequence elements which located at-95/58 and +45/+50 are important for optimal transcription of CR1 gene.

• Journal of Microbiology
• /
• 제34권2호
• /
• pp.137-143
• /
• 1996

We isolated a promoter inducible by paraquat, a superoxide-generating agent, from Escherichia coli using a promoter-probing plasmid pRS415. From sequence analysis we found out the promoter is for fpr ENCODING nadph : ferredoxin oxidoreductase. We constructed on operon fusion of lacZ gene with fpr promoter to monitor the expression of the gene in the single-copy state. LacZ expression generators, menadione and plumbagin, also induced the expression of .betha.-galactosidase in the fusion strain. On the other hand, no significant induction was observed by treatment with hydrogen peroxide, ethanol, and heat shock. Induction of .betha.-galactosidase was significantly reduced by introducing a .DELTA. sox 8 :: cat of soxS3 :: Tn10 mutation into the fusion strain, indicating that fpr gene is a member of the soxRS regulon. The transcriptional start site was determined by primer extension analysis. Possible roles of fpr induction in superoxide stress were discussed.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제20권2호
• /
• pp.107-114
• /
• 2010

For stable germline transformation, the promoter of Bombyx mori cytoplasmic actin gene (BmA3) has been used for ubiquitous expression of transgenes. So far, no strong promoter is available for ubiquitous expression in B. mori, excluding BmA3 promoter. To identify more powerful promoter than previously reported BmA3 promoter, we isolated 9 clones that show stronger signal compared to BmA3 by a dot blot hybridization. Among these 9 clones, we focused on one clone which has high amino acid homology (85%) with hypothetical protein 32 gene of Lonomia obliqua. This clone, named bHp32 (B. mori hypothetical protein 32) was ubiquitously expressed in all tissues and developmental stage of fifth instar B. mori larvae. As result of promoter assay using dual luciferase assay system, we found the highest transcription activity region (-1,200/+220) in the 5'-flanking region of bHp32 gene, which has 42-fold more intensive promoter activity than BmA3 promoter. Moreover, the bHp32 promoter was normally regulated in Bm5, Sf9, and S2 cells. Therefore, we suggest that bHp32 promoter may be used more powerful and effectively for transgene expression in various insects containing B. mori as a universal promoter.