• 한국미생물·생명공학회지
• /
• 제36권4호
• /
• pp.353-359
• /
• 2008

Hepatitis C virus (HCV) is known as the causative agent of blood transmitted hepatitis. Two viral proteins, E2 and NS5A, are known to exert interferon resistance of HCV via PKR pathway. Here, we report a third protein, the RNA-dependent RNA polymerase (NS5B) of HCV, induced interferon resistance inhibiting p56 pathway. p56 was shown to interact with p48 subunit of eukaryotic initiation factor 3 (eIF3). This interaction inhibited formation of ternary complex in translation initiation. Using dual reporter assay system, we observed that the translation decreased when interferon alpha was added to the culture. But, in the presence of HCV NS5B, the translation partly recovered. NS5B and p48 subunit of eIF3 were shown to interact. This interaction seems to inhibit the interaction between p48 and p56. This is the first report that a virus exerts interferon resistance via p56 pathway.

• 한국지능시스템학회논문지
• /
• 제22권6호
• /
• pp.786-792
• /
• 2012

마이크로어레이는 수만 가지 이상의 DNA 또는 RNA를 기판위에 배열해 놓은 것이며 이 기술을 이용하여 대량의 유전자 발현을 탐색할 수 있게 되었다. 그렇지만 마이크로어레이는 실험자가 탐색하려는 특정 표현형에 대해서 설계된 실험방법을 이용하므로 제한된 숫자의 유전자 발현만을 관찰할 수 있다. 본 논문에서는 MicroRNAs(miRNAs)와 Protein-Protein Interaction(PPI) 정보를 포함하고 있는 데이터베이스를 활용하여 마이크로어레이 데이터의 의미적 확장 방법을 제시하고자 한다. 또한 Online Mendelian Inheritance in Man(OMIM) 및 International Statistical Classification of Diseases and Related Health Problems, $10^{th}$ Revision(ICD-10)을 이용하여 질병 간 유전적 공통점 파악을 시도하였다. 이러한 접근방법을 통하여 새로운 생물학적 시각을 제공할 수 있을 것으로 기대된다.

• 생명과학회지
• /
• 제30권6호
• /
• pp.501-512
• /
• 2020

제주조릿대 잎은 항염, 해열 및 이뇨작용을 가지고 있어 위궤양, 목마름 및 토혈 치료를 위한 민간의약으로 사용되어 왔다. 본 저자들은 제주조리대 잎에서 분리한 피토케미칼 풍부 추출물(PRE)과 그 에틸아세테이트 분획물(EPRE)은 여러 위암 세포주에서 세포사멸을 유도하는 항암 효과가 있다고 보고한 바 있다. 본 연구는 EPRE의 세포사멸 유도 기전에 관여하는 분자표적들을 탐색하기 위하여 EPRE을 처리한 SNU-16 세포에서 mRNA와 microRNA (miRNA)의 프로파일 변화를 분석하였다. RNA sequencing 분석을 통해 총 2,875개의 차등적으로 발현되는 유전자들(DEGs)을 동정하였다. 유전자 온톨로지(GO)와 KEGG 경로 분석 결과, EPRE는 세포사멸, 유사 분열-활성화 단백질 키나제(MAPK) 및 염증 반응, 종양 괴사 인자(TNF) 신호 전달 및 암 경로에 관여하는 유전자들의 발현을 조절하는 것으로 나타났다. 단백질-단백질 상호 작용(PPI) 네트워크 분석으로 세포사멸 및 세포죽음과 관련된 유전자들 간의 상호작용들을 확인할 수 있었다. 그리고, miRNA sequencing 분석을 통해 총 27개의 차별적으로 발현되는 miRNAs (DEMs)를 동정하였다. GO와 KEGG 경로 분석 결과, EPRE는 세포주기, 세포사멸 및 tropomyosin-receptor-kinase (TRK) 수용체 신호 전달, 성장인자-β(TGF-β), 핵인자 κB (NF-κB) 및 암 경로에 관여하는 miRNAs의 발현을 조정하였다. 본 연구결과는 EPRE의 항암 효과의 근본적인 메커니즘에 대한 통찰력을 제공한다.

• Journal of Genetic Medicine
• /
• 제3권1호
• /
• pp.15-19
• /
• 1999

We have investigated the genetic variation in the human apo B mRNA editing protein (apobec-1) gene. Exon 3 of the apobec-1 gene was amplified by polymerase chain reaction. After detection of an additional band by single strand conformational polymorphism (SSCP) analysis, sequencing of the SSCP-shift sample revealed a single-base mutation. The mutation was a CGG transversion at codon 80 resulting in a lleRMet substitution. This substitution was confirmed by restriction fragment length polymorphism analysis since a Pvull site is abolished by the substitution. Population and family studies confirmed that the inheritance of the genotypes for apobec-1 gene polymorphism is controlled by two codominant alleles (P1 and P2). A significant difference in plasma triglyceride was detected among the different apobec-1 genotypes in the CAD patients (P<0.05). Our study could provide the basis for elucidating the interaction between genetic variation of the apobec-1 gene and disorders related to lipid metabolism.

• The Plant Pathology Journal
• /
• 제28권1호
• /
• pp.40-48
• /
• 2012

$Potato$ $virus$ $X$ (PVX) replication is precisely regulated by regulatory viral sequences and by viral and/or host proteins. In a previous study, we identified a 54-kDa cellular tobacco protein that bound to a region within the first 46 nucleotides (nt) of the 5' non-translated region (NTR) of the viral genome. Optimal binding was dependent upon the presence of an ACCA sequence at nt 10-13. To identify host factors that bind to 5' NTR elements including AC-rich sequences as well as stemloop 1 (SL1), we used northwestern blotting and matrixassisted laser desorption/ionization time-of-flight mass spectrometry for peptide mass fingerprinting. We screened several host factors that might affect PVX replication and selected a candidate protein, $Nicotiana$ $tabacum$ WRKY transcription factor 1 (NtWRKY1). We used a $Tobacco$ $rattle$ $virus$ (TRV)-based virus-induced gene silencing (VIGS) system to investigate the role of NtWRKY1 in PVX replication. Silencing of $WRKY1$ in $Nicotiana$ $benthamiana$ caused lethal apical necrosis and allowed an increase in PVX RNA accumulation. This result could reflect the balancing of PVX accumulation in a systemic $N.$ $benthamiana$ host to maintain PVX survival and still produce a suitable appearance of mosaic and mottle symptoms. Our results suggest that PVX may recruit the WRKY transcription factor, which binds to the 5' NTR of viral genomic RNA and acts as a key regulator of viral infection.

• Journal of Korean Neurosurgical Society
• /
• 제65권5호
• /
• pp.697-709
• /
• 2022

Objective : The present study aimed to identify the function of ischemic stroke (IS) patients' peripheral blood and its role in IS, explore the pathogenesis, and provide direction for clinical research progress by comprehensive bioinformatics analysis. Methods : Two datasets, including GSE58294 and GSE22255, were downloaded from Gene Expression Omnibus database. GEO2R was utilized to obtain differentially expressed genes (DEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs were performed using the database annotation, visualization and integrated discovery database. The protein-protein interaction (PPI) network of DEGs was constructed by search tool of searching interactive gene and visualized by Cytoscape software, and then the Hub gene was identified by degree analysis. The microRNA (miRNA) and miRNA target genes closely related to the onset of stroke were obtained through the miRNA gene regulatory network. Results : In total, 36 DEGs, containing 27 up-regulated and nine down-regulated DEGs, were identified. GO functional analysis showed that these DEGs were involved in regulation of apoptotic process, cytoplasm, protein binding and other biological processes. KEGG enrichment analysis showed that these DEGs mediated signaling pathways, including human T-cell lymphotropic virus (HTLV)-I infection and microRNAs in cancer. The results of PPI network and cytohubba showed that there was a relationship between DEGs, and five hub genes related to stroke were obtained : SOCS3, KRAS, PTGS2, EGR1, and DUSP1. Combined with the visualization of DEG-miRNAs, hsa-mir-16-5p, hsa-mir-181a-5p and hsa-mir-124-3p were predicted to be the key miRNAs in stroke, and three miRNAs were related to hub gene. Conclusion : Thirty-six DEGs, five Hub genes, and three miRNA were obtained from bioinformatics analysis of IS microarray data, which might provide potential targets for diagnosis and treatment of IS.

• Molecules and Cells
• /
• 제43권5호
• /
• pp.469-478
• /
• 2020

Hepatitis C virus (HCV) propagation is highly dependent on cellular proteins. To identify the host factors involved in HCV propagation, we previously performed protein microarray assays and identified the LIM and SH3 domain protein 1 (LASP-1) as an HCV NS5A-interacting partner. LASP-1 plays an important role in the regulation of cell proliferation, migration, and protein-protein interactions. Alteration of LASP-1 expression has been implicated in hepatocellular carcinoma. However, the functional involvement of LASP-1 in HCV propagation and HCV-induced pathogenesis has not been elucidated. Here, we first verified the protein interaction of NS5A and LASP-1 by both in vitro pulldown and coimmunoprecipitation assays. We further showed that NS5A and LASP-1 were colocalized in the cytoplasm of HCV infected cells. NS5A interacted with LASP-1 through the proline motif in domain I of NS5A and the tryptophan residue in the SH3 domain of LASP-1. Knockdown of LASP1 increased HCV replication in both HCV-infected cells and HCV subgenomic replicon cells. LASP-1 negatively regulated viral propagation and thereby overexpression of LASP-1 decreased HCV replication. Moreover, HCV propagation was decreased by wild-type LASP-1 but not by an NS5A binding-defective mutant of LASP-1. We further demonstrated that LASP-1 was involved in the replication stage of the HCV life cycle. Importantly, LASP-1 expression levels were increased in persistently infected cells with HCV. These data suggest that HCV modulates LASP-1 via NS5A in order to regulate virion levels and maintain a persistent infection.

• Bulletin of the Korean Chemical Society
• /
• 제26권2호
• /
• pp.285-291
• /
• 2005

The nonstructural protein 5B (NS5B) of hepatitis C virus (HCV) is the viral RNA-dependent RNA polymerase (RdRp), which is the essential catalytic enzyme for the viral replication and is an appealing target for the development of new therapeutic agents against HCV infection. A small amount of serum from a single patient with hepatitis C was used to get the genome of a Korean HCV isolate. Sequence analysis of NS5B 1701 nucleotides showed the genotype of a Korean isolate to be subtype 1b. The soluble recombinant HCV NS5B polymerase lacking the C-terminal 24 amino acids was expressed and purified to homogeneity. With the highly purified NS5B protein, we established in vitro systems for RdRp activity to identify potential polymerase inhibitors. The rhodanine family compounds were found to be potent and specific inhibitors of NS5B from high throughput screening (HTS) assay utilizing the scintillation proximity assay (SPA) system. The binding mode of an inhibitor was analyzed by measuring various kinetic parameters. Lineweaver-Burk plots of the inhibitor suggested it binds not to the active site of NS5B polymerase, but to an allosteric site of the enzyme. The activity of NS5B in in vitro polymerase reactions with homopolymeric RNA requires interaction with multiple substrates that include a template/primer and ribonucleotide triphosphate. Steady-state kinetic parameter, such as Km, was determined for the ribonucleotide triphosphate. One of compounds found interacts directly with the viral polymerase and inhibits RNA synthesis in a manner noncompetitively with respect to UTP. Furthermore, we also investigated the ability of the compound to inhibit NS5B-directed viral RNA replication using the Huh7 cell-based HCV replicon system. The investigation is potentially very useful for the utility of such compounds as anti-hepatitic agents.

• Journal of Microbiology and Biotechnology
• /
• 제34권2호
• /
• pp.233-239
• /
• 2024

N6-methyladenosine (m6A) RNA methylation has recently emerged as a significant co-transcriptional modification involved in regulating various RNA functions. It plays a vital function in numerous biological processes. Enzymes referred to as m6A methyltransferases, such as the methyltransferase-like (METTL) 3-METTL14-Wilms tumor 1 (WT1)-associated protein (WTAP) complex, are responsible for adding m6A modifications, while m6A demethylases, including fat mass and obesity-associated protein (FTO) and alkB homolog 5 (ALKBH5), can remove m6A methylation. The functions of m6A-methylated RNA are regulated through the recognition and interaction of m6A reader proteins. Recent research has shown that m6A methylation takes place at multiple sites within hepatitis B virus (HBV) RNAs, and the location of these modifications can differentially impact the HBV infection. The addition of m6A modifications to HBV RNA can influence its stability and translation, thereby affecting viral replication and pathogenesis. Furthermore, HBV infection can also alter the m6A modification pattern of host RNA, indicating the virus's ability to manipulate host cellular processes, including m6A modification. This manipulation aids in establishing chronic infection, promoting liver disease, and contributing to pathogenesis. A comprehensive understanding of the functional roles of m6A modification during HBV infection is crucial for developing innovative approaches to combat HBV-mediated liver disease. In this review, we explore the functions of m6A modification in HBV replication and its impact on the development of liver disease.

• 한국생물물리학회:학술대회논문집
• /
• 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
• /
• pp.43-43
• /
• 1999

Signal peptides of secretary proteins interact with various membranes and non-membrane components during the translocation. We investigated the interaction of signal peptides of ribose binding protein (RBP) with Escherichia coli (E.coli) signal recognition particle (SRP), SecA and lipid bilayer. Previous studies showed that the functional signal peptides inhibit the GTPase activity of E.coli SRP which consisted of F로 and 4.5S RNA.(omitted)