• Journal of Plant Biotechnology
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• 제35권3호
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• pp.169-176
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• 2008

SA는 천연 페놀 화합물로써 식물체가 생성하는 호르몬 중의 하나이다. SA는 특히 병저항성, 생물학적, 비생물학적 스트레스로 인해 합성이 촉진되며 식물 방어 기작을 일으킨다고 알려져 있다. 식물의 방어 기작은 바로 식물에서 얻어지는 생산량에 영향을 미치기 때문에 SA에 대한 연구가 많이 되어져 왔다. 하지만 SA를 이해하기에는 아직까지 많은 연구가 필요 되어 지고 있다. 따라서 본 연구는 애기장대에서 SA 생합성하는데 중요한 효소인 SID2가 병저항성이 강한 siz1-2 돌연변이체와 야생형에서 어떠한 조절의 차이를 보이는 지를 SID2 promoter에 의해서 조절되는 GUS와 LUC를 가진 각각의 형질전환 식물체를 통하여 관찰하였다. GUS의 발현을 GUS histochemical assay, GUS enzyme assay 그리고 LUC의 발현을 CCD 카메라를 이용한 이미지 촬영과 Luciferase enzyme assay 수행한 결과, siz1-2를 사용한 형질전환 식물체에서 야생형에 비해 발현이 높게 일어났다. 이것을 바탕으로 SA에 반응하는 유전자들의 발현이 siz1-2 돌연변이체에서는 높은 이유가 SID2의 발현이 높게 조절 받기 때문이라는 것을 SID2 promoter:GUS::LUC/siz1-2 형질전환 식물체를 통해 알 수 있었다.

• 생명과학회지
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• 제27권4호
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• pp.456-463
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• 2017

본 연구는 3종의 한약재(감초(Glycyrrhizae radix), 황기(Astragali radix) 및 산약(Dioscorea rhizome)) 추출물의 에스트로겐 유사활성 및 조골세포 증식과 분화에 미치는 영향을 검토하고자 실험을 진행하였다. 에스트로겐 유사활성 측정을 위하여 인체 유방암 세포주인 MCF7 세포를 luciferase 유전자를 리포터로 사용하는 에스트로겐 반응성 리포터 시스템을 가지는 세포로 형질전환하여 사용하였다. 상기 세포를 이용하여 추출물의 에스트로겐 유사활성을 측정한 결과, 한약재 추출물이 음성대조군과 비교하여 1.11배~5.73배 높은 에스트로겐 유사활성을 나타내었다. 그 중 감초 추출물이 가장 높은 에스트로겐 유사활성을 보였다. 감초 추출물의 에스트로겐 유사활성은 추출물의 농도가 $50{\mu}g/ml$ 및 $500{\mu}g/ml$ 일 때 각각 $10^{-8}M$ 및 $10^{-7}M$ $17{\beta}-estradiol$과 거의 유사한 활성을 나타내었다. 조골세포주인 MC3T3-E1 세포를 이용한 실험에서는 감초 추출물의 농도가 $1{\sim}1,000{\mu}g/ml$ 범위일 때 독성을 나타내지 않았다. 황기 추출물은 조골세포에 있어서 유의적인 세포 증식률을 보이지 않았다. 그러나, 감초 및 산약 추출물은 각각 148% 및 133%의 최대 증식률을 보였다. 또한, 감초 추출물은 대조군과 비교하여 alkaline phosphatase(ALP) 활성이 증가하였으며, 추출물의 농도가 $100{\mu}g/ml$ 일 때 최대 122%의 ALP 활성을 나타내었다. 또한, Alizarin red S 염색법을 이용한 석회화 형성능 측정에서도 대조군과 비교하여 석회화가 증가하였다. 이러한 결과로 미루어 보아 감초 추출물이 골 형성 및 골다공증 예방 효과가 우수한 식품 소재인 것으로 사료된다.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.407-414
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• 2004

The expression of CYP3A4 gene is induced by a variety of structurally unrelated xenobiotics including the antibiotic rifampicin, pregnenolone 16-carbonitrile (PCN), and endogenous hormones, that might mediate through steroid and xenobiotic receptor (SXR) system. The molecular mechanisms underlying regulation of CYP3A4 gene expression have not been understood. In order to gain the insight of the molecular mechanism of CYP3A4 gene expression, study has been undertaken to investigate if the histone deacetylation is involved in the regulation of CYP3A4 gene expression by proximal promoter in human hepatoma HepG2 cells. Also we have investigated to see if SXR is involved in the regulation of CYP3A4 proximal promoter activity in human hepatoma HepG2 cells. HepG2 cells were transfected with a plasmid PCYP3A4-Luc containing ${\~}1kb$ of the CYP3A4 proximal promoter region (-863 to +64 bp) in front of a reporter gene, luciferase, in the presence or absence of pSAP-SXR. In HepG2 cells, CYP3A4 inducers, such as rifampicin, PCN and RU486 showed minimal stimulation of CYP3A4 proximal promoter activity in the absence of SXR and histone deacetylase (HDAC) inhibitors. 4-Dimethylamino-H-[4-(2-hydroxycarbamoylvinyl)benzyl]benzamide (IN2001), a new class HDAC inhibitor significantly increased CYP3A4 proximal promoter activity over untreated control cells and rifampicin concomitant treatment with IN2001 increased further CYP3A4 proximal promoter activity that was stimulated by IN2001 The results of this study demon-strated that both HDAC inhibitors and SXR are essential to increase of CYP3A4 proximal promoter activity by CYP3A4 inducers such as PCN, rifampicin, and RU486. Especially SXR seems to be important for the dose dependent response of CYP3A4 inducing chemicals to stimulate CYP3A4 proximal promoter activity. Also this data suggested that HDAC inhibitors seemed to facilitate the CYP3A4 proximal promoter to be activated by chemicals.

• Molecules and Cells
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• 제26권5호
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• pp.468-473
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• 2008

Low-density lipoprotein (LDL) induces cell proliferation in human aortic smooth muscle cells (hAoSMCs), which may be involved in atherogenesis and intimal hyperplasia. Recent studies have demonstrated that $Cl^-$ channels are related to vessel cell proliferation induced by a variety of stimuli. In this study, we investigated a potential role of $Cl^-$ channels in the signaling pathway of LDL effects on hAoSMC proliferation with a focus on the activation of Erk1/2-PI3K/Akt and the subsequent upregulation of Egr-1. $Cl^-$ channel blockers, DIDS, but neither NPPB nor Furosemide, completely abolished the LDL-induced DNA synthesis and cell proliferation. Moreover, DIDS, but not NPPB, significantly decreased LDL-stimulated $Cl^-$ concentration, as judged by flow cytometry analysis using MQAE as a $Cl^-$-detection dye. DIDS pretreatment completely abolished the activation of Erk1/2 and PI3K/Akt in a dose-dependent manner that is the hallmark of LDL activation, as judged by Western blot and proliferation assays. Moreover, pretreatment with DIDS ($Cl^-$ channel blockers) but not LY294002 (PI3K inhibitors) completely abolished the LDL-induced upregulation of Egr-1 to the same extent as PD98059 (MEK inhibitors to inhibit Erk), as judged by Western blot and luciferase reporter assays. This is the first report, to our knowledge, that DIDS-sensitive $Cl^-$-channels play a key role in the LDL-induced cell proliferation of hAoSMCs via the activation of Erk1/2 and PI3K/Akt and the upregulation of Egr-1.

• BMB Reports
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• 제40권5호
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• pp.749-756
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• 2007

Phosphorylation on serine/threonine or tyrosine residues of target proteins is an essential and significant regulatory mechanism in signal transduction during many cellular and life processes, including spermatogenesis, oogenesis and fertilization. In the present work, we reported the isolation and characterization of mouse testis-specific serine/threonine kinase 5 (Tssk5), which contains four alternatively spliced variants including, Tssk5$\alpha$, Tssk5$\beta$, Tssk5$\gamma$ and Tssk5$\delta$. Moreover, the locus of Tssk5 is on chromosome 14qC3 and the four variants had a similar high expression in the testis and the heart; however, had a low expression in other tissues, except for Tssk5$\alpha$ which also had comparably high expression in the spleen. Each variant of Tssk5 expression began in the testis 16 days after birth. Aside from TSSK5$\alpha$, the other isoforms have an insertion of ten amino acid residues (RLTPSLSAAG) in region VIb (HRD domain) (His-Arg-Asp). Moreover, only TSSK5$\alpha$ exhibited kinase activity and consistently, a further Luciferase Reporter Assay demonstrated that TSSK5$\beta$, TSSK5$\gamma$ and TSSK5$\delta$ cannot be stimulated at the CREB/CRE responsive pathway in comparison to TSSK5$\alpha$. These findings suggest that TSSK5$\beta$, TSSK5$\gamma$, TSSK5$\delta$ may be pseudokinases due to the insertion, which may damage the structure responsible for active kinase activity. Pull-down assay experiments indicated that TSSK5$\beta$, TSSK5 $\gamma$ and TSSK5$\delta$ can directly interact with TSSK5$\alpha$. In summary, these four isoforms with similar expression patterns may be involved in spermatogenesis through a coordinative way in testis.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2325-2331
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• 2013

Objective: To detect effects of plumbagin on proliferation and apoptosis in non-small cell lung cancer cell lines, and investigate the underlying mechanisms. Materials and Methods: Human non-small cell lung cancer cell lines A549, H292 and H460 were treated with various concentrations of plumbagin. Cell proliferation rates was determined using both cell counting kit-8 (CCK-8) and clonogenic assays. Apoptosis was detected by annexin V/propidium iodide double-labeled flow cytometry and TUNEL assay. The levels of reactive oxygen species (ROS) were detected by flow cytometry. Activity of NF-${\kappa}B$ was examined by electrophoretic mobility shift assay (EMSA) and luciferase reporter assay. Western blotting was used to assess the expression of both NF-${\kappa}B$ regulated apoptotic-related gene and activation of p65 and $I{\kappa}B{\kappa}$. Results: Plumbagin dose-dependently inhibited proliferation of the lung cancer cells. The IC50 values of plumbagin in A549, H292, and H460 cells were 10.3 ${\mu}mol/L$, 7.3 ${\mu}mol/L$, and 6.1 ${\mu}mol/L$ for 12 hours, respectively. The compound concentration-dependently induced apoptosis of the three cell lines. Treatment with plumbagin increased the intracellular level of ROS, and inhibited the activation of NK-${\kappa}B$. In addition to inhibition of NF-${\kappa}B$/p65 nuclear translocation, the compound also suppressed the degradation of $I{\kappa}B{\kappa}$. ROS scavenger NAC highly reversed the effect of plumbagin on apoptosis and inactivation of NK-${\kappa}B$ in H460 cell line. Treatment with plumbagin also increased the activity of caspase-9 and caspase-3, downregulated the expression of Bcl-2, upregulated the expression of Bax, Bak, and CytC. Conclusions: Plumbagin inhibits cell growth and induces apoptosis in human lung cancer cells through an NF-${\kappa}B$-regulated mitochondrial-mediated pathway, involving activation of ROS.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4671-4676
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• 2014

Background: MicroRNA-200a (miR-200a) has been reported to regulate tumour progression in several tumours but little is known about its role in neuroblastoma. Our aim was to investigate the potential role and mechanism of miR-200a in neuroblastomas. Materials and Methods: Expression levels of miR-200a in tissues were determined using RT-PCR. The effect of miR-200a and shAP-$2{\gamma}$ on cell viability was evaluated using MTS assays, and target protein expression was determined using Western blotting and RT-PCR. Luciferase reporter plasmids were constructed to confirm direct targeting. Results were reported as mean${\pm}$S.E.M and differences were tested for significance using the 2-tailed Students t-test. Results: We determined that miR-200a expression was significantly lower in neuroblastoma tumors than the adjacent non-cancer tissue. Over-expression of miR-200 are reduced cell viability in neuroblastoma cells and inhibited tumor growth in mouse xenografts. We identified AP-$2{\gamma}$ as a novel target for miR-200a in neuroblastoma cells. Thus miR-200a targets the 3'UTR of AP-$2{\gamma}$ and inhibits its mRNA and protein expression. Furthermore, our result showed that shRNA knockdown of AP-$2{\gamma}$ in neuroblastoma cells results in significant inhibit of cell proliferation and tumor growth in vitro, supporting an oncogenic role of AP-$2{\gamma}$ in neuroblastoma. Conclusions: Our study revealed that miR-200a is a candidate tumor suppressor in neuroblastoma, through direct targeting of AP-$2{\gamma}$. These findings re-enforce the proposal of AP-$2{\gamma}$ as a therapeutic target in neuroblastoma.

• BMB Reports
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• 제44권2호
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• pp.123-128
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• 2011

Leucine-rich repeat containing protein 10 (LRRC10) is characterized as a cardiac-specific gene, suggesting a role in heart development and disease. A severe cardiac morphogenic defect in zebrafish morphants was recently reported but a contradictory result was found in mice, suggesting a more complicated molecular mechanism exists during mouse embryonic development. To elucidate how LRRC10 is regulated, we analyzed the 5'enhancer region approximately 3 kilo bases (kb) upstream of the Lrrc10 start site using luciferase reporter gene assays. Our characterization of the Lrrc10 promoter indicates it possesses complicated cis-and trans-acting elements. We show that GATA4 and MEF2C could both increase transcriptional activity of Lrrc10 promoter individually but that they do not act synergistically, suggesting that there exists a more complex regulation pattern. Surprisingly, knockout of Gata4 and Mef2c binding sites in the 5’enhancer region (-2,894/-2,889) didn't change the transcriptional activity of the Lrrc10 promoter and the likely GATA4 binding site identified was located in a region only 100 base pair (bp) upstream of the promoter. Our data provides insight into the molecular regulation of Lrrc10 expression, which probably also contributes to its tissue-specific expression.

• Asian-Australasian Journal of Animal Sciences
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• 제33권3호
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• pp.398-407
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• 2020

Objective: The Yip1 domain family (YIPF) proteins were proposed to function in endoplasmic reticulum (ER) to Golgi transport and maintenance of the morphology of the Golgi, which were homologues of yeast Yip1p and Yif1p. YIPF3, the member 3 of YIPF family was a homolog of Yif1p. The aim of present study was to investigate the expression and regulation mechanism of porcine YIPF3. Methods: Quantitative realtime polymerase chain reaction (qPCR) was used to analyze porcine YIPF3 mRNA expression pattern in different tissues and pig kidney epithelial (PK15) cells stimulated by polyinosine-polycytidylic acid (poly [I:C]). Site-directed mutations combined with dual luciferase reporter assays and electrophoretic mobility shift assay (EMSA) were employed to reveal transcription regulation mechanism of porcine YIPF3. Results: Results showed that the mRNA of porcine YIPF3 (pYIPF3) was widely expressed with the highest levels in lymph and lung followed by spleen and liver, while weak in heart and skeletal muscle. Subcellular localization results indicated that it expressed in Golgi apparatus and plasma membranes. Upon stimulation with poly (I:C), the level of this gene was dramatically up-regulated in a time- and concentration-dependent manner. pYIPF3 core promoter region harbored three cis-acting elements which were bound by ETS proto-oncogene 2 (ETS2), zinc finger and BTB domain containing 4 (ZBTB4), and zinc finger and BTB domain containing 14 (ZBTB14), respectively. In which, ETS2 and ZBTB4 both promoted pYIPF3 transcription activity while ZBTB14 inhibited it, and these three transcription factors all played important regulation roles in tumorigenesis and apoptosis. Conclusion: The pYIPF3 mRNA expression was regulated by ETS2, ZBTB4, and ZBTB14, and its higher expression in immune organs might contribute to enhancing ER to Golgi transport of proteins, thus adapting to the immune response.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10439-10444
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• 2015

Many chemotherapeutic agents have been successfully used to treat hepatocellular carcinoma (HCC); however, the development of chemoresistance in liver cancer cells usually results in a relapse and worsening of prognosis. It has been demonstrated that DNA methylation and histone modification play crucial roles in chemotherapy resistance. Currently, extensive research has shown that there is another potential mechanism of gene expression control, which is mediated through the function of short noncoding RNAs, especially for microRNAs (miRNAs), but little is known about their roles in cancer cell drug resistance. In present study, by taking advantage of miRNA effects on the resistance of human hepatocellular carcinoma cells line to cisplatin, it has been demonstrated that miR-340 were significantly downregulated whereas Nrf2 was upregulated in HepG2/CDDP (cisplatin) cells, compared with parental HepG2 cells. Bioinformatics analysis and luciferase assays of Nrf2-3'-untranslated region-based reporter constructor indicated that Nrf2 was the direct target gene of miR-340, miR-340 mimics suppressing Nrf2-dependent antioxidant pathway and enhancing the sensitivity of HepG2/CDDP cells to cisplatin. Interestingly, transfection with miR-340 mimics combined with miR-340 inhibitors reactivated the Nrf2 related pathway and restored the resistance of HepG2/CDDP cells to CDDP. Collectively, the results first suggested that lower expression of miR-340 is involved in the development of CDDP resistance in hepatocellular carcinoma cell line, at least partly due to regulating Nrf2-dependent antioxidant pathway.