• 제목/요약/키워드: Silenced

검색결과 86건 처리시간 0.028초

Evaluation of MiR-34 Family and DNA Methyltransferases 1, 3A, 3B Gene Expression Levels in Hepatocellular Carcinoma Following Treatment with Dendrosomal Nanocurcumin

  • Chamani, Fatemeh;Sadeghizadeh, Majid;Masoumi, Mahbobeh;Babashah, Sadegh
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권sup3호
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    • pp.219-224
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    • 2016
  • Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver making up more than 80 percent of cases. It is known to be the sixth most prevalent cancer and the third most frequent cause of cancer related death worldwide. Epigenetic regulation constitutes an important mechanism by which dietary components can selectively activate or inactivate target gene expression. The miR-34 family members including mir-34a, mir-34b and mir-34c are tumor suppressor micro RNAs, which are expressed in the majority of normal tissues. Several studies have indicated silencing of miR-34 expression via DNA methylation in multiple types of cancers. Bioactive nutrients like curcumin (Cur) have excellent anticarcinogenic activity and minimal toxic manifestations in biological systems. This compound has recently been determined to induce epigenetic changes. However, Cur is lipophilic and has a poor systemic bioavailability and poor absorption. Its bioavailability is increased through employing dendrosome nanoparticles. The aim of the current study was to investigate the effect of dendrosomal nanocurcumin (DNC) on expression of mir-34 family members in two HCC cell lines, HepG2 and Huh7. We performed the MTT assay to evaluate DNC and dendrosome effects on cell viability. The ability of DNC to alter expression of the mir-34 family and DNA methyltransferases (DNMT1, DNMT3A and 3B) was evaluated using semi-quantitative and quantitative PCR. We observed the entrance of DNC into HepG2 and Huh7 cells. Gene expression assays indicated that DNC treatment upregulated mir34a, mir34b and mir34c expression (P<0.05) as well as downregulated DNMT1, DNMT3A and DNMT3B expression (P<0.05) in both HepG2 and Huh7 cell lines. DNC also reduced viability of Huh7 and HepG2 cells through restoration of miR-34s expression. We showed that DNC could awaken the epigenetically silenced miR-34 family by downregulation of DNMTs. Our findings suggest that DNC has potential in epigenetic therapy of HCC.

The Existence of a Putative Regulatory Element in 3'-Untranslated Region of Proto-oncogene HOX11's mRNA

  • Li, Yue;Jiang, Zhao-Zhao;Chen, Hai-Xu;Leung, Wai-Keung;Sung, Joseph J.Y.;Ma, Wei-Jun
    • BMB Reports
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    • 제38권4호
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    • pp.500-506
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    • 2005
  • HOX11 encodes a homeodomain-containing transcription factor which directs the development of the spleen during embryogenesis. While HOX11 expression is normally silenced through an unknown mechanism in all tissues by adulthood, the deregulation of HOX11 expression is associated with leukemia, such as T-cell acute lymphoblastic leukemia. The elucidation of regulatory elements contributing to the molecular mechanism underlying the regulation of HOX11 gene expression is of great importance. Previous reports of HOX11 regulatory elements mainly focused on the 5'-flanking region of HOX11 on the chromosome related to transcriptional control. To expand the search of putative cis-elements involved in HOX11 regulation at the post-transcriptional level, we analyzed HOX11 mRNA 3'-untranslated region (3'UTR) and found an AU-rich region. To characterize this AU-rich region, in vitro analysis of HOX11 mRNA 3'UTR was performed with human RNA-binding protein HuR, which interacts with AU-rich element (ARE) existing in the 3'UTR of many growth factors' and cytokines' mRNAs. Our results showed that the HOX11 mRNA 3'UTR can specifically bind with human HuR protein in vitro. This specific binding could be competed effectively by typical ARE containing RNA. After the deletion of the AU-rich region present in the HOX11 mRNA 3'UTR, the interaction of HOX11 mRNA 3'UTR with HuR protein was abolished. These findings suggest that HOX11 mRNA 3'UTR contains cis-acting element which shares similarity in the action pattern with RE-HuR interactions and may involve in the post-transcriptional regulation of the HOX11 gene.

ZNF424, a novel human KRAB/C2H2 zinc finger protein, suppresses NFAT and p21 pathway

  • Wang, Yuequn;Zhou, Junnei;Ye, Xiangli;Wan, Yongqi;Li, Youngqing;Mo, Xiaoyan;Yuan, Wuzhou;Yan, Yan;Luo, Na;Wang, Zequn;Fan, Xiongwei;Deng, Yun;Wu, Xiushan
    • BMB Reports
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    • 제43권3호
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    • pp.212-218
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    • 2010
  • Zinc finger-containing transcription factors are the largest single family of transcriptional regulators in mammals, which play an essential role in cell differentiation, cell proliferation, apoptosis, and neoplastic transformation. Here we have cloned a novel KRAB-related zinc finger gene, ZNF424, encoding a protein of 555aa. ZNF424 gene consisted of 4 exons and 3 introns, and mapped to chromosome 19p13.3. ZNF424 gene was ubiquitously expressed in human embryo tissues by Northern blot analysis. ZNF424 is conserved across species in evolution. Using a GFP-labeled ZNF424 protein, we demonstrate that ZNF424 localizes mostly in the nucleus. Transcriptional activity assays shows ZNF424 suppresses transcriptional activity of L8G5-luciferase. Overexpression of ZNF424 in HEK-293 cells inhibited the transcriptional activity of NFAT and p21, which may be silenced by siRNA. The results suggest that ZNF424 protein may act as a transcriptional repressor that suppresses NFAT and p21 pathway to mediate cellular functions.

MiR-144-3p and Its Target Gene β-Amyloid Precursor Protein Regulate 1-Methyl-4-Phenyl-1,2-3,6-Tetrahydropyridine-Induced Mitochondrial Dysfunction

  • Li, Kuo;Zhang, Junling;Ji, Chunxue;Wang, Lixuan
    • Molecules and Cells
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    • 제39권7호
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    • pp.543-549
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    • 2016
  • MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neuro-degenerative diseases, Parkinson's disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, ${\beta}$-amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes involved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor ${\gamma}$ coactivator-$1{\alpha}$(PGC-$1{\alpha}$), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.

Rice OsACDR1 (Oryza sativa Accelerated Cell Death and Resistance 1) Is a Potential Positive Regulator of Fungal Disease Resistance

  • Kim, Jung-A;Cho, Kyoungwon;Singh, Raksha;Jung, Young-Ho;Jeong, Seung-Hee;Kim, So-Hee;Lee, Jae-eun;Cho, Yoon-Seong;Agrawal, Ganesh K.;Rakwal, Randeep;Tamogami, Shigeru;Kersten, Birgit;Jeon, Jong-Seong;An, Gynheung;Jwa, Nam-Soo
    • Molecules and Cells
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    • 제28권5호
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    • pp.431-439
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    • 2009
  • Rice Oryza sativa accelerated cell death and resistance 1 (OsACDR1) encodes a putative Raf-like mitogen-activated protein kinase kinase kinase (MAPKKK). We had previously reported upregulation of the OsACDR1 transcript by a range of environmental stimuli involved in eliciting defense-related pathways. Here we apply biochemical, gain and loss-of-function approaches to characterize OsACDR1 function in rice. The OsACDR1 protein showed autophosphorylation and possessed kinase activity. Rice plants overexpressing OsACDR1 exhibited spontaneous hypersensitive response (HR)-like lesions on leaves, upregulation of defense-related marker genes and accumulation of phenolic compounds and secondary metabolites (phytoalexins). These transgenic plants also acquired enhanced resistance to a fungal pathogen (Magnaporthe grisea) and showed inhibition of appressorial penetration on the leaf surface. In contrast, loss-of-function and RNA silenced OsACDR1 rice mutant plants showed downregulation of defense-related marker genes expressions and susceptibility to M. grisea. Furthermore, transient expression of an OsACDR1:GFP fusion protein in rice protoplast and onion epidermal cells revealed its localization to the nucleus. These results indicate that OsACDR1 plays an important role in the positive regulation of disease resistance in rice.

푸에르토리코의 인종주의를 읽는 세 가지 사회문화적 코드 (The Sociocultural Codes for Interpreting Racism in Puerto Rico)

  • 이은아
    • 비교문화연구
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    • 제44권
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    • pp.7-28
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    • 2016
  • 이 글에서는 푸에르토리코에 깊게 뿌리내린 인종주의를 이해하기 위해 세 가지 핵심적 용어를 중심으로 흑인성에 대한 사회문화적 배경을 살펴보고자 한다. 카세리오스, 레게톤, 트리게뇨스는 모두 푸에르토리코 사회의 인종민주주의 이데올로기와 깊은 연관이 있다. 카세리오스는 저소득층을 위한 공동주택으로서 범죄척결의 대상지로 지목되면서 흑인성에 고착된 폭력성과 무절제한 성, 가난의 이미지를 보다 확산시키는 결과를 낳았다. 레게톤은 2000년대 중반 세계적인 성공을 거두면서 푸에르토리코 섬뿐만 아니라 뉴욕 푸에르토리코의 아프로디아스포라의 음악적 힘에 주목하게 만들었다. 아프리카계 카리브 음악의 부상과 확산을 통해 푸에르토리코 문화적 정체성에서 흑인성이 갖는 의미를 재발견하는 계기가 되었다. 트리게뇨스는 물라토의 다른 이름으로서 최근 들어 혼혈인을 아우르는 통합적 용어로 자주 사용된다. 인종민주주의의 허상을 드러내는 한계와 더불어 흑인성의 대안적 개념이 될 수 있는 가능성을 지니고 있다. 이 세 가지 개념을 둘러싼 논의들은 고착화된 인종주의를 드러냄과 동시에 극복을 위한 문화적 노력과 잠재력을 엿보게 해준다. 인종적 불평등과 위계적 사회질서에 대해 역사적으로 침묵하도록 만든 인종주의의 고질성과 편재성에 저항하기 위해서 보다 강력하고 대응적인 문화정치학이 필요할 것이다.

간에서 지방산 분할에 대한 지방산결합 단백질 5의 역할 (The role of Fatty acid binding protein 5 (Fabp5) in fatty acid partitioning in the liver)

  • 박재승
    • 디지털융복합연구
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    • 제17권8호
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    • pp.283-291
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    • 2019
  • 간성 지방생성과 지방 대사에 있어서 FABP5의 역할에 대하여 알아보고자 하였다. 마우스에 바이러스 입자를 이용하여 간에서 FABP5를 과발현 그리고 침묵시켜 이용하였다. 마우스에 서양식 또는 일반 사료를 1주일간 섭취시키고 24시간 동안 금식한 후 희생하였다. 간을 기계적으로 분쇄하여 웨스턴 블?으로 단백질 농도를 측정하였고, mRANA 분석에는 RT-PCR을 이용하였다. 간과 혈청의 지질 분석에는 박층 크로마토그래피를 이용하였다. 서양식이나 고농도 포화 지방식을 급식한 쥐에서 FABP5 발현이 높은 증가를 보였으나, FABP5 mRNA 발현은 급식에 비해 단식조건에서 급격히 감소하였다. FABP5를 과발현 시킨 상태에서 급식과 금식을 실시한 결과 간성 TG가 중요하게 증가하였다. 간성 유리 콜레스테롤은 급식상태에서 현저히 감소하였다. FABP5 발현 억제 시 간성 TG가 상당히 감소하였다. 결과들에서 보듯이, FABP5가 간지질 생성에 중요한 역할을 하며, 정상 상태 및 탄수화물 유도 조건에서 간성 TG 저장형성에 관여할 것으로 사료된다. FABP5는 비알코올성 지방간 질환, 대사증후군, 비만 치료에 활용될 수 있을 것으로 사료된다. 더 나아가, FABP5 발현에 어떤 전사인자가 관여하는지에 대한 연구가 필요하다.

Avian leukosis virus subgroup J and reticuloendotheliosis virus coinfection induced TRIM62 regulation of the actin cytoskeleton

  • Li, Ling;Zhuang, Pingping;Cheng, Ziqiang;Yang, Jie;Bi, Jianmin;Wang, Guihua
    • Journal of Veterinary Science
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    • 제21권3호
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    • pp.49.1-49.14
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    • 2020
  • Background: Coinfection with avian leukosis virus subgroup J (ALV-J) and reticuloendotheliosis virus (REV) is common in chickens, and the molecular mechanism of the synergistic pathogenic effects of the coinfection is not clear. Exosomes have been identified as new players in the pathogenesis of retroviruses. The different functions of exosomes depend on their cargo components. Objectives: The aim of this study was to investigate the function of co-regulation differentially expressed proteins in exosomes on coinfection of ALV-J and REV. Methods: Here, viral replication in CEF cells infected with ALV-J, REV or both was detected by immunofluorescence microscopy. Then, we analyzed the exosomes isolated from supernatants of chicken embryo fibroblast (CEF) cells single infected and coinfected with ALV-J and REV by mass spectrometry. KEGG pathway enrichment analyzed the co-regulation differentially expressed proteins in exosomes. Next, we silenced and overexpressed tripartite motif containing 62 (TRIM62) to evaluate the effects of TRIM62 on viral replication and the expression levels of NCK-association proteins 1 (NCKAP1) and actin-related 2/3 complex subunit 5 (ARPC5) determined by quantitative reverse transcription polymerase chain reaction. Results: The results showed that coinfection of ALV-J and REV promoted the replication of each other. Thirty proteins, including TRIM62, NCK-association proteins 1 (NCKAP1, also known as Nap125), and Arp2/3-5, ARPC5, were identified. NCKAP1 and ARPC5 were involved in the actin cytoskeleton pathway. TRIM62 negatively regulated viral replication and that the inhibition of REV was more significant than that on ALV-J in CEF cells coinfected with TRIM62. In addition, TRIM62 decreased the expression of NCKAP1 and increased the expression of ARPC5 in coinfected CEF cells. Conclusions: Collectively, our results indicated that coinfection with ALV-J and REV competitively promoted each other's replication, the actin cytoskeleton played an important role in the coinfection mechanism, and TRIM62 regulated the actin cytoskeleton.

Ginsenoside Rb2 suppresses cellular senescence of human dermal fibroblasts by inducing autophagy

  • Kyeong Eun Yang;Soo-Bin Nam;Minsu Jang;Junsoo Park;Ga-Eun Lee;Yong-Yeon Cho;Byeong-Churl Jang;Cheol-Jung Lee;Jong-Soon Choi
    • Journal of Ginseng Research
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    • 제47권2호
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    • pp.337-346
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    • 2023
  • Background: Ginsenoside Rb2, a major active component of Panax ginseng, has various physiological activities, including anticancer and anti-inflammatory effects. However, the mechanisms underlying the rejuvenation effect of Rb2 in human skin cells have not been elucidated. Methods: We performed a senescence-associated β-galactosidase staining assay to confirm cellular senescence in human dermal fibroblasts (HDFs). The regulatory effects of Rb2 on autophagy were evaluated by analyzing the expression of autophagy marker proteins, such as microtubule-associated protein 1A/1B-light chain (LC) 3 and p62, using immunoblotting. Autophagosome and autolysosome formation was monitored using transmission electron microscopy. Autophagic flux was analyzed using tandem-labeled GFP-RFP-LC3, and lysosomal function was assessed with Lysotracker. We performed RNA sequencing to identify potential target genes related to HDF rejuvenation mediated by Rb2. To verify the functions of the target genes, we silenced them using shRNAs. Results: Rb2 decreased β-galactosidase activity and altered the expression of cell cycle regulatory proteins in senescent HDFs. Rb2 markedly induced the conversion of LC3-I to LC3-II and LC3 puncta. Moreover, Rb2 increased lysosomal function and red puncta in tandem-labeled GFP-RFP-LC3, which indicate that Rb2 promoted autophagic flux. RNA sequencing data showed that the expression of DNA damage-regulated autophagy modulator 2 (DRAM2) was induced by Rb2. In autophagy signaling, Rb2 activated the AMPK-ULK1 pathway and inactivated mTOR. DRAM2 knockdown inhibited autophagy and Rb2-restored cellular senescence. Conclusion: Rb2 reverses cellular senescence by activating autophagy via the AMPK-mTOR pathway and induction of DRAM2, suggesting that Rb2 might have potential value as an antiaging agent.

신종교영화의 유형과 특성 (Typology and the Features of Films about New Religious Movements)

  • 박종천
    • 대순사상논총
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    • 제33집
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    • pp.179-218
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    • 2019
  • 이 글은 신종교운동을 비도덕적이고 반사회적인 소종파(cult)로 비판하면서 선정적이고 자극적인 방식으로 영상화하여 소비하는 신종교영화의 문제점을 지적하고, 신종교운동을 기성종교에서 벗어나려는 소극적 주변종교와 기성종교를 대체하려는 적극적 대안종교의 관점에서 신종교영화를 분석할 수 있는 유형론을 제시하였다. 특히 신종교현상의 반사회적 일탈을 강조하면서 세뇌와 탈세뇌의 관점에 치우친 사회비평형 신종교영화와는 달리, 최근 새롭게 떠오르고 있는 신종교영화의 새로운 유형으로 공감성찰형 신종교영화와 신앙참여형 신종교 영화의 특성에 대한 분석을 전개하였다. <오쇼 라즈니쉬의 문제적 유토피아>(2018)를 비롯한 공감성찰형 신종교영화들이 규범적인 단일 프레임을 넘어서서 다면적인 구성과 다성적인 목소리를 갖춘 열린 프레임을 통해 내부자의 자기성찰과 외부자의 타자공감이 가능하도록 한 반면, <화평의 길>(1984)을 비롯한 신앙참여형 신종교영화들은 후천개벽이나 해원상생 등의 대안종교적 비전을 통해 기성종교에서 소외되거나 배제되었던 주변인들의 원한을 풀고 말할 수 없었던 하위주체들의 목소리를 회복시키는 새로운 영상적 방식을 선보였다.