• 제목/요약/키워드: promoter assay

검색결과 360건 처리시간 0.026초

Wnt/$\beta$-catenin/Tcf Signaling Induces the Transcription of a Tumor Suppressor Axin2, a Negative Regulator of the Signaling Pathway

  • Jho, Eek-hoon;Tong Zhang;Claire Domon;Joo, Choun-Ki;Freund, Jean-Noel;Frank Costantini
    • 한국응용약물학회:학술대회논문집
    • /
    • 한국응용약물학회 2001년도 추계학술대회 및 정기총회
    • /
    • pp.108-108
    • /
    • 2001
  • Axin2/Conductin/Axil and its ortholog Axin are negative regulators of the Wnt signaling pathway, which promote the phosphorylation and degradation of ${\beta}$-catenin. While Axin is expressed ubiquitously, Axin2 mRNA was seen in a restricted pattern during mouse embryogenesis and organogenesis. Because many sites of Axin2 expression overlapped with those of several Wnt genes, we tested whether Axin2 was induced by Wnt signaling. Endogenous Axin2 mRNA and protein expression could be rapidly induced by activation of the Wnt pathway, and Axin2 reporter constructs, containing a 5.6 kb DNA fragment including the promoter and first intron, were also induced. This genomic region contains eight Tcf/LEF consensus binding sites, five of which are located within longer, highly conserved non-coding sequences. The mutation or deletion of these Tcf/LEF sites greatly diminished induction by ${\beta}$-catenin, and mutation of the Tcf/LEF site T2 abolished protein binding in an electrophoretic mobility-shift assay. These results strongly suggest that Axin2 is a direct target of the Wnt pathway, mediated through Tcf/LEF factors. The 5.6 kb genomic sequence was sufficient to direct the tissue specific expression of d2EGFP in transgenic embryos, consistent with a role for the Tcf/LEF sites and surrounding conserved sequences in the in vivo expression pattern of Axin2. Our results suggest that Axin2 participates in a negative feedback loop, which could serve to limit the duration or intensity of a Wnt-initiated signal.

  • PDF

Post-Transcriptional Control of Tropoelastin in Aortic Smooth Muscle Cells Affects Aortic Dissection Onset

  • Qi, You-Fei;Shu, Chang;Xiao, Zhan-Xiang;Luo, Ming-Yao;Fang, Kun;Guo, Yuan-Yuan;Zhang, Wen-Bo;Yue, Jie
    • Molecules and Cells
    • /
    • 제41권3호
    • /
    • pp.198-206
    • /
    • 2018
  • Aortic dissection (AD) is a catastrophic disease with high mortality and morbidity, characterized with fragmentation of elastin and loss of smooth muscle cells. Although AD has been largely attributable to polymorphisms defect in the elastin-coding gene, tropoelastin (TE), other undermined factors also appear to play roles in AD onset. Here, we investigated the effects of post-transcriptional control of TE by microRNAs (miRNAs) on elastin levels in aortic smooth muscle cells (ASMC). We found that miR-144-3p is a miRNA that targets TE mRNA in both human and mouse. Bioinformatics analyses and dual luciferase reporter assay showed that miR-144-3p inhibited protein translation of TE, through binding to the 3'-UTR of the TE mRNA. Interestingly, higher miR-144-3p levels and lower TE were detected in the ASMC obtained from AD patients, compared to those from non-AD controls. In a mouse model for human AD, infusion of adeno-associated viruses (serotype 6) carrying antisense for miR-144-3p (asmiR-144-3p) under CAG promoter significantly reduced the incidence and severity of AD, seemingly through enhancement of TE levels in ASMC. Thus, our data suggest an essential role of miR-144-3p on the pathogenesis of AD.

Association of Cytokine Gene Polymorphisms with Gastritis in a Kazakh Population

  • Kulmambetova, Gulmira Nigmetzhanovna;Imanbekova, Meruert Kuatbekovna;Logvinenko, Andrey Alexeevich;Sukashev, Adilbek Temirzhanovich;Filipenko, Maxim Leonidovich;Ramanсulov, Erlan Mirhaidarovich
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권18호
    • /
    • pp.7763-7768
    • /
    • 2014
  • Background: Gastritis and gastric cancer are the most common diseases in the Kazakh population. Polymorphisms in genes coding of cytokines have been played important role with gastric disease risk. The risk alleles of cytokines in patients with gastritis can predict the risk of developing gastric cancer. The aim of this study was to investigate cytokine gene polymorphisms as risk factors for the development of gastritis in a case-control study with gastritis patients and healthy individuals from the Kazakh ethnic group, living in North Kazakhstan. Materials and Methods: The polymerase chain reaction followed by direct sequencing were used for detection of two functional polymorphisms in the IL1 gene family, and TaqMan SNP Genotyping Assay Sets were applied for three potentially functional polymorphisms in the IL10 gene, and one in the TNFA promoter. Results: Association analysis of studied allelic variants and the development of gastritis in H. pylori-positive patients showed that IL1B -31C/C, IL1B -511T/T and IL1RN -2/2 allelic variants were associated with development of gastritis (OR=1.8 (1.07-3.16), p=0.025; OR=1.7 (1.04-2.99), p=0.035, and OR=4.92 (2.45-9.85), p<0.001) respectively. Haplotype C-Т that combines both homozygous allelic variants of IL1B gene also had a statistically significant association with slightly higher OR (OR: 1.43, 95% CI: 1.08-1.88). Conclusions: The data from the current study showed that the genotype IL-1B -511Т/-31C-IL1-RN-2 and H. pylori infection increase risk of gastritis in the Kazakh population. That genotype combination might be a factor increasing the risk of developing gastric cancer.

유전자총을 이용한 상추 내로의 배추 Glutathione Reductase (GR)유전자의 도입 (Transformation of Chinese Cabbage Glutathione Reductase (GR) gene into Lettuce (Lactuca sativa L.) with Particle Bombardment)

  • 정재동;이부자;이효신;김창길
    • 식물조직배양학회지
    • /
    • 제27권6호
    • /
    • pp.475-478
    • /
    • 2000
  • 상추에 particle bombardment를 이용한 배추 Glutathione Reductase (GR)유전자의 형질전환효율 향상 및 형질전환체의 유전분석에 관한 실험을 수행하여 얻은 결과를 요약하면 다음과 같다. Particle bombardment 이용시 사출 전 4시간, 사출 후 16시간 동안 삼투조절제인 0.6M serbitolfmannitol 을 처리하여 형질전환시킨 상추 자엽조직에서 GUS 반응 spot이 가장 많았다. 0.3, 0.6, 1.5 kbp로 나타나는 3가지 종류의 primer를 사용하여 PCR한 결과 각각의 primer에 homology를 타나내는 band를 확인하여 355 promoter와 BcGRl유전자가 삽입이 된 것을 확인하였다. 형질전환된 상추의 자식 종자를 채종하여 kanamycin 200mg/L이 첨가된 MS배지에 파종하여 형질전환시키지 않은 상추의 자식 종자와 비교해 본 결과, 형질전환된 상추의 종자에서 발아된 유묘의 약 70%정도가 kanamycin에 대해 내성을 나타내었다.

  • PDF

Cooperative transcriptional activation of ATP-binding cassette sterol transporters ABCG5 and ABCG8 genes by nuclear receptors including Liver-X-Receptor

  • Back, Su Sun;Kim, Jinsu;Choi, Daehyung;Lee, Eui Sup;Choi, Soo Young;Han, Kyuhyung
    • BMB Reports
    • /
    • 제46권6호
    • /
    • pp.322-327
    • /
    • 2013
  • The ATP-binding cassette transporters ABCG5 and ABCG8 form heterodimers that limit absorption of dietary sterols in the intestine and promote cholesterol elimination from the body through hepatobiliary secretion. To identify cis-regulatory elements of the two genes, we have cloned and analyzed twenty-three evolutionary conserved region (ECR) fragments using the CMV-luciferase reporter system in HepG2 cells. Two ECRs were found to be responsive to the Liver-X-Receptor (LXR). Through elaborate deletion studies, regions containing putative LXREs were identified and the binding of $LXR{\alpha}$ was demonstrated by EMSA and ChIP assay. When the LXREs were inserted upstream of the intergenic promoter, synergistic activation by $LXR{\alpha}/RXR{\alpha}$ in combination with GATA4, $HNF4{\alpha}$, and LRH-1, which had been shown to bind to the intergenic region, was observed. In conclusion, we have identified two LXREs in ABCG5/ABCG8 genes for the first time and propose that these LXREs, especially in the ECR20, play major roles in regulating these genes.

Expression and Characterization of Human T-Cell Leukemia Virus Type-I Env and Gag Proteins

  • Son, Kyung-Hwa;Kim, Byong-Moon;Lee, Taik-You;Kim, Seong-Ryong;Kim, Kun-Soo;Lee, Jeong-Kug;Yang, Jai-Myung
    • Journal of Microbiology and Biotechnology
    • /
    • 제9권3호
    • /
    • pp.311-317
    • /
    • 1999
  • Human T-cell leukemia virus Type-I (HTLV-I) is etiologically associated with rare adult T-cell leukemia, a malignant T-cell disorder. cDNAs encoding p24 (gag), gp21(env), and pXII of HTLV-I were amplified by polymerase chain reaction (PCR) using the genomic DNA extracted from HUT102 cell line as a template. The amplified cDNAs were cloned into the Escherichia coli expression vectors and over-expression of the recombinant proteins were achieved by adding IPTG into the culture media in order to induce the promoter. The molecular weights of the recombinant p24, gp21, and pXII, determined by SDS-PAGE, were found to be approximately 28 kDa, 23 kDa, and 15 kDa, respectively. Reactivity of the recombinant proteins with human sera was tested by the immunoblot assay. The gp21 and p24 reacted against the sera obtained from HTLV-I-infected individuals but not against the sera obtained from normal persons. These results suggest that the recombinant proteins expressed in E. coli were recognized by antibodies in sera from HTLV-I infected patients. These recombinant proteins would be applicable for detecting the presence of antibodies against HTLV-I in human blood samples.

  • PDF

Crystal Structure of the Regulatory Domain of MexT, a Transcriptional Activator of the MexEF-OprN Efflux Pump in Pseudomonas aeruginosa

  • Kim, Suhyeon;Kim, Songhee H.;Ahn, Jinsook;Jo, Inseong;Lee, Zee-Won;Choi, Sang Ho;Ha, Nam-Chul
    • Molecules and Cells
    • /
    • 제42권12호
    • /
    • pp.850-857
    • /
    • 2019
  • The Gram-negative opportunistic pathogen, Pseudomonas aeruginosa, has multiple multidrug efflux pumps. MexT, a LysR-type transcriptional regulator, functions as a transcriptional activator of the MexEF-OprN efflux system. MexT consists of an N-terminal DNA-binding domain and a C-terminal regulatory domain (RD). Little is known regarding MexT ligands and its mechanism of activation. We elucidated the crystal structure of the MexT RD at 2.0 Å resolution. The structure comprised two protomer chains in a dimeric arrangement. MexT possessed an arginine-rich region and a hydrophobic patch lined by a variable loop, both of which are putative ligand-binding sites. The three-dimensional structure of MexT provided clues to the interacting ligand structure. A DNase I footprinting assay of full-length MexT identified two MexT-binding sequence in the mexEF-oprN promoter. Our findings enhance the understanding of the regulation of MexT-dependent activation of efflux pumps.

Particle Bombardment에 의한 고구마의 형질전환 (Genetic Transformation of Sweet Potato by Particle Bombardment)

  • 민성란;정원중;이영복;유장렬
    • 식물조직배양학회지
    • /
    • 제25권5호
    • /
    • pp.329-333
    • /
    • 1998
  • Escherichia coli의 $\beta$-glucuronidase (GUS) 유전자를 고구마의 배발생세포괴에 particle bombardment로 도입하여 재분화 식물체에 발현시켰다. CaMV35S-GUS 융합유전자와 선발표지로서 neomycin phosphotransferase유전자가 들어있는 binary 운반체 pBI121 DNA를 텅스텐 입자로 코팅하여 정단분열 조직 유래의 배발생 세포괴에 bombarding하였다. Bombarding된 세포괴를 1mg/L 2,4-D와 100mg/L kanamycin이 첨가된 MS 배지로 옮겨 한달 간격으로 6개월동안 계대배양하였다. Kanamycin 저항성 캘러스를 0.03mg/L 2iP, 0.03 mg/L ABA 및 50 mg/L kanamycin이 들어있는 MS 배지로 옮겨 체세포배를 유도하였고, kanamycin이 첨가되지 않은 MS 기본배지에서 식물체로 발달시켰다. 토양에서 생육중인 6개체의 식물을 대상으로 PCR과 northern분석을 수행한 결과 GUS 유전자가 식물체 genome에 안정적으로 도입, 발현되었음이 확인되었다. 조직화학적 분석으로 GUS 유전자가 형질전환 식물체에서 발현됨을 밝혔다.

  • PDF

Defining the N-Linked Glycosylation Site of Hantaan Virus Envelope Glycoproteins Essential for Cell Fusion

  • Zheng, Feng;Ma, Lixian;Shao, Lihua;Wang, Gang;Chen, Fengzhe;Zhang, Ying;Yang, Song
    • Journal of Microbiology
    • /
    • 제45권1호
    • /
    • pp.41-47
    • /
    • 2007
  • The Hantaan virus (HTNV) is an enveloped virus that is capable of inducing low pH-dependent cell fusion. We molecularly cloned the viral glycoprotein (GP) and nucleocapsid (NP) cDNA of HTNV and expressed them in Vero E6 cells under the control of a CMV promoter. The viral gene expression was assessed using an indirect immunofluorescence assay and immunoprecipitation. The transfected Vero E6 cells expressing GPs, but not those expressing NP, fused and formed a syncytium following exposure to a low pH. Monoclonal antibodies (MAbs) against envelope GPs inhibited cell fusion, whereas MAbs against NP did not. We also investigated the N-linked glycosylation of HTNV GPs and its role in cell fusion. The envelope GPs of HTNV are modified by N-linked glycosylation at five sites: four sites on G1 (N134, N235, N347, and N399) and one site on G2 (N928). Site-directed mutagenesis was used to construct eight GP gene mutants, including five single N-glycosylation site mutants and three double-site mutants, which were then expressed in Vero E6 cells. The oligosaccharide chain on residue N928 of G2 was found to be crucial for cell fusion after exposure to a low pH. These results suggest that G2 is likely to be the fusion protein of HTNV.

Lentivirus System을 이용한 Glucocorticoid 유도 Reporter 유전자 발현의 분석 (In vitro Analysis of Glucocorticoid-induced Reporter Gene Expression Using Lentivirus System)

  • 이미숙;김지연;허송욱
    • 한국해양바이오학회지
    • /
    • 제2권2호
    • /
    • pp.81-85
    • /
    • 2007
  • 글루코코르티코이드의 다양한 생리학적 과정은 이 호르몬에 의해 활성화된 수용체가 표적 유전자의 전사를 촉진 혹은 억제시킴으로써 일어나게 된다. 본 논문은 렌티바이러스 리포터 시스템을 이용하여 글루코코르티코이드 호르몬에 의한 GR 활성을 핵내에서 GRE에 의해 유도된 리포터 단백질인 mRFP 또는 루시퍼라아제의 발현을 통해 정성, 정량화 하였다. 그 결과 GR이 endogenous 하게 발현되는 HeLa 세포에서 코티졸을 처리하였을 때 활성화된 GR에 의해 GRE-inducible한 RFP와 루시퍼라아제의 발현이 각각 공초점 형광 현미경과 IVIS-200을 이용하여 형광 또는 BLI을 통해 증가함을 확인하였다. 이러한 결과를 통해 렌티바이러스 리포터 시스템을 이용한 연구는 세포 내에서 뿐 만 아니라 향후 생체내에서의 GR signaling을 모니터링하는데 유용하게 사용되어질 수 있을 것이다.

  • PDF