• Title/Summary/Keyword: RNA binding proteins

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Biochemical and Molecular Biological Studies on the DNA Replication of Bacteriophage T7 (Bacteriophage T7의 유전자 복제기작에 관한 생화학적, 분자생물학적 특성 연구)

  • KIM Young Tae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.2
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    • pp.209-218
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    • 1995
  • Bacteriophage T7 gene 2.5 protein, a single-stranded DNA binding protein, has been implicated in T7 DNA replication, recombination, and repair. Purified gene 2.5 protein has been shown to interact with the phage encoded gene 5 protein (DNA polymerase) and gene 4 proteins (helicase and primase) and stimulates their activities. Genetic analysis of T7 phage defective in gene 2.5 shows that the gene 2.5 protein is essential for T7 DNA replication and growth. T7 phage that contain null mutants of gene 2.5 were constructed by homologous recombination. These mutant phage $(T7\Delta2.5)$ cannot grow in Escherichia coli. After infection of E. coli with $T7\Delta2.5$, host DNA synthesis is shut off, and $T7\Delta2.5$ DNA synthesis is reduced to less than $1\%$ of wild-type phage DNA synthesis (Kim and Richardson, 1993, Proc. Natl. Aca. Sci. USA, 90, 10173-10177). A truncated gene 2.5 protein $(GP2.5-\Delta21C)$ deleted the 21 carboxyl terminal amino acids was constructed by in vitro mutagenesis. $GP2.5-\Delta21C$ cannot substitute for wild-type gene 2.5 protein in vivo; the phage are not viable and exhibit less than $1\%$ of the DNA synthesis observed in wild-type phage-infected cells. $GP2.5-\Delta21C$ has been purified to apparent homogeneity from cells overexpressing its cloned gene. Purified $GP2.5-\Delta21C$ does not physically into「act with T1 gene 4 protein as measured by affinity chromatography and immunoblot analysis. The mutant protein cannot stimulate T7 gene 4 protein activity on RNA-primed DNA synthesis and primer synthesis. These results suggest that C-terminal domain of gene 2.5 protein is essential for protein-protein interactions.

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Pectinase-treated Panax ginseng ameliorates hydrogen peroxide-induced oxidative stress in GC-2 sperm cells and modulates testicular gene expression in aged rats

  • Kopalli, Spandana Rajendra;Cha, Kyu-Min;Jeong, Min-Sik;Lee, Sang-Ho;Sung, Jong-Hwan;Seo, Seok-Kyo;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • v.40 no.2
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    • pp.185-195
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    • 2016
  • Background: To investigate the effect of pectinase-treated Panax ginseng (GINST) in cellular and male subfertility animal models. Methods: Hydrogen peroxide ($H_2O_2$)-induced mouse spermatocyte GC-2spd cells were used as an in vitro model. Cell viability was measured using MTT assay. For the in vivo study, GINST (200 mg/kg) mixed with a regular pellet diet was administered orally for 4 mo, and the changes in the mRNA and protein expression level of antioxidative and spermatogenic genes in young and aged control rats were compared using real-time reverse transcription polymerase chain reaction and western blotting. Results: GINST treatment ($50{\mu}g/mL$, $100{\mu}g/mL$, and $200{\mu}g/mL$) significantly (p < 0.05) inhibited the $H_2O_2$-induced ($200{\mu}M$) cytotoxicity in GC-2spd cells. Furthermore, GINST ($50{\mu}g/mL$ and $100{\mu}g/mL$) significantly (p < 0.05) ameliorated the $H_2O_2$-induced decrease in the expression level of antioxidant enzymes (peroxiredoxin 3 and 4, glutathione S-transferase m5, and glutathione peroxidase 4), spermatogenesis-related protein such as inhibin-${\alpha}$, and specific sex hormone receptors (androgen receptor, luteinizing hormone receptor, and follicle-stimulating hormone receptor) in GC-2spd cells. Similarly, the altered expression level of the above mentioned genes and of spermatogenesis-related nectin-2 and cAMP response element-binding protein in aged rat testes was ameliorated with GINST (200 mg/kg) treatment. Taken together, GINST attenuated $H_2O_2$-induced oxidative stress in GC-2 cells and modulated the expression of antioxidant-related genes and of spermatogenic-related proteins and sex hormone receptors in aged rats. Conclusion: GINST may be a potential natural agent for the protection against or treatment of oxidative stress-induced male subfertility and aging-induced male subfertility.

EXPRESSION OF DOMINANT NEGATIVE p63 ISOFORM IN WELL-DIFFERENCIATED ORAL SQUAMOUS CELL CARCINOMA (분화도 좋은 구강 편평상피세포암종에서 Dominant Negative p63 isoform의 발현)

  • Kim, In-Su;Kim, Chul-Hwan;Kim, Kyung-Wook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.3
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    • pp.191-198
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    • 2007
  • The p53 which is well known as tumor suppressor gene is located at 17p13. p53 is a sequence-specific DNA binding transcription factor that responds to certain cytotoxic stresses, such as DNA damage, by enhancing the transcription of genes that regulate cell-cycle progression as well as programmed cell death. The p63 gene that is located at 3q27-29, is recognized members of the p53 family, and responsible for the transcription of 6 isoforms. Three isoforms ($TAp63{\alpha}$, $TAp63{\beta}$, $TAp63{\gamma}$) contain an N-terminal transactivation (TA) domain and can induce apoptosis. The other 3 isoforms (${\Delta}Np63{\alpha}$, ${\Delta}Np63{\beta}$, ${\Delta}Np63{\gamma}$) lack the TA domain and may function in a dominant-negative fashion by inhibiting the transactivation functions of p53 and TAp63 proteins, and thus act as oncoproteins. A number of studies have investigated the role of p63 in human squamous cell carcinomas from different organs. Only a few studies have examined ${\Delta}Np63$ isoform in oral squamous cell carcinoma including normal epithelium. This study aimed to evaluate expression of ${\Delta}Np63$ isoform in human oral squamous cell carcinoma tissue and normal mucosa. The 3 cases of well differenciated oral squamous cell carcinoma specimen including adjacent normal mucosa were examined, and immunohistochemical study with monoclonal antibody(4A4) and tumor cell apoptosis analysis with Transmission Electon Microscopy were studied. And, RT-PCR analysis was done for expression of ${\Delta}Np63$ isoform. The results were as followed. 1. Normal gingiva showed the restricted p63 expression in basal cell layer. 2. Well differentiated squamous cell carcinoma showed mainly p63 expression in overall area of malignancy, especially in basal cell layer to adjacent stromal tissue. 3. Tumor cells around keratinized area with no p63 expression disclosed less micro-organelle in decreased size cytoplasm and severe chromatin margination with nuclear destruction that means apoptosis. 4. Comparison of mRNA expression of ${\Delta}Np63$ isoform by RT-PCR showed variable expression of ${\Delta}Np63$ isoform, but ${\Delta}Np63{\alpha}$ was most highly expressed in all 3 tumor specimen. From theses results, it should be suggested that ${\Delta}Np63$ isoform expression in well differentiated squamous cell carcinoma was closely related to tumor oncogenesis, expecially overexpression of ${\Delta}Np63{\alpha}$ is a most important factor in tumor genesis of oral squamous cell carcinoma.

SREBP as a Global Regulator for Lipid Metabolism (지질대사 조절에서 SREBP의 역할)

  • Lee, Wonhwa;Seo, Young-kyo
    • Journal of Life Science
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    • v.28 no.10
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    • pp.1233-1243
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    • 2018
  • Sterol regulatory-element binding proteins (SREBPs) are a family of transcription factors that regulate lipid homeostasis and metabolism by controlling the expression of enzymes required for endogenous cholesterol, fatty acid (FA), triacylglycerol, and phospholipid synthesis. The three SREBPs are encoded by two different genes. The SREBP1 gene gives rise to SREBP-1a and SREBP-1c, which are derived from utilization of alternate promoters that yield transcripts in which distinct first exons are spliced to a common second exon. SREBP-2 is derived from a separate gene. Additionally, SREBPs are implicated in numerous pathogenic processes, such as endoplasmic reticulum stress, inflammation, autophagy, and apoptosis. They also contribute to obesity, dyslipidemia, diabetes mellitus, and nonalcoholic fatty liver diseases. Genome-wide analyses have revealed that these versatile transcription factors act as important nodes of biological signaling networks. Changes in cell metabolism and growth are reciprocally linked through SREBPs. Anabolic and growth signaling pathways branch off and connect to multiple steps of SREBP activation and form complex regulatory networks. SREBPs are activated through the PI3K-Akt-mTOR pathway in these processes, but the molecular mechanism remains to be understood. This review aims to provide a comprehensive understanding of the role of SREBPs in physiology and pathophysiology at the cell, organ, and organism levels.

Enhanced Calreticulin Expression Promotes Calcium-dependent Apoptosis in Postnatal Cardiomyocytes

  • Lim, Soyeon;Chang, Woochul;Lee, Byoung Kwon;Song, Heesang;Hong, Ja Hyun;Lee, Sunju;Song, Byeong-Wook;Kim, Hye-Jung;Cha, Min-Ji;Jang, Yangsoo;Chung, Namsik;Choi, Soon-Yong;Hwang, Ki-Chul
    • Molecules and Cells
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    • v.25 no.3
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    • pp.390-396
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    • 2008
  • Calreticulin (CRT) is one of the major $Ca^{2+}$ binding chaperone proteins of the endoplasmic reticulum (ER) and an unusual luminal ER protein. Postnatally elevated expression of CRT leads to impaired development of the cardiac conductive system and may be responsible for the pathology of complete heart block. In this study, the molecular mechanisms that affect $Ca^{2+}$-dependent signal cascades were investigated using CRT-overexpressing cardiomyocytes. In particular, we asked whether calreticulin plays a critical role in the activation of $Ca^{2+}$-dependent apoptosis. In the cells overexpressing CRT, the intracellular calcium concentration was significantly increased and the activity of PKC and level of SECAR2a mRNA were reduced. Phosphorylation of Akt and ERKs decreased compared to control. In addition the activity of the anti-apoptotic factor, Bcl-2, was decreased and the activities of pro-apoptotic factor, Bax, p53 and caspase 8 were increased, leading to a dramatic augmentation of caspase 3 activity. Our results suggest that enhanced CRT expression in mature cardiomyocytes disrupts intracellular calcium regulation, leading to calcium-dependent apoptosis.

DNA and Proteomic Expression of Cervi parvum cornu Herbal-acupuncture Solution (CPC-HAS) in HepG2 carcinomar cells (녹용약침액(鹿茸藥鍼液)의 간암세포주(肝癌細胞柱)에 대한 DNA 및 단백질 발현(發顯))

  • Ryu, Sung-Hyun;Lee, Kyung-Min;Lee, Bong-Hyo;Lim, Seong-Chul;Jung, Tae-Young;Seo, Jung-Chul
    • Journal of Pharmacopuncture
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    • v.9 no.2
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    • pp.5-16
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    • 2006
  • Objective : It has long been known about the osteogenic effect of CPC-HAS on bone tissues. However, it has not been determined the effect of CPC-HAS on cancer cells. The purpose of this study is to screen the CPC-HAS mediated differentially expressed genes in cancer cells such as HepG2 hepatoma cells. Oligonucleotide microarray and proteomics approaches were employed to screen the differential expression genes. Methods : CPC-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. Cells were treated with various concentrations of CPC-HAS (0.1, 0.5, 1.5, 10, 20mg/ml) for 24 h. Cell toxicity was tested by MTT assay. To screen the differentially expressed genes in cancer cells, cells were treated with 1.5mg/ml of CPC-HAS. For oligonucleotide microarray assay, total RNA was used for gene expression analysis using oligonucleotide Genechip(Human genome Ul33 Plus 2.0., Affimatrix Co.). For proteomic analysis, total protein was analyzed by 2D gel electrophoresis and Q-TOF mass spectrometer. Results : It has no cytotoxic effects on both HepG2 cell in all concentrations(0.l, 0.5, 1.5, 10, 20mg/ml). In oligonucleotide microarray assay, the number of more than twofold differentially regulated known genes was 23 with 5 up-regulated and 18 down-regulated genes in HepG2 cells. In proteomic analysis, three spots were identified by 2D-gel electrophoresis and Q-TOF analysis. Two down-regulated proteins were aldehyde dehydrogenase 1 and enolase 1, and up-regulated protein was fatty acid binding protein 1 by 1.5mg/ml of CPC-HAS. Discussion : This study showed the screening of CPC-HAS mediated differentially regulated genes using combined approaches of oligonucleotide microarray and proteomic analysis. The screened genes will be used for the better understanding of the therapeutic effects of CPC-HAS on cancer fields.

Effect of ciglitazone on adipogenic transdifferentiation of bovine skeletal muscle satellite cells

  • Zhang, Junfang;Li, Qiang;Yan, Yan;Sun, Bin;Wang, Ying;Tang, Lin;Wang, Enze;Yu Jia;Nogoy, Kim Margarette Corpuz;Li, Xiangzi;Choi, Seong-Ho
    • Journal of Animal Science and Technology
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    • v.63 no.4
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    • pp.934-953
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    • 2021
  • Ciglitazone is a member of the thiazolidinedione family, and specifically binds to peroxisome proliferator-activated receptor-γ (PPARγ), thereby promoting adipocyte differentiation. We hypothesized that ciglitazone as a PPARγ ligand in the absence of an adipocyte differentiation cocktail would increase adiponectin and adipogenic gene expression in bovine satellite cells (BSC). Muscle-derived BSCs were isolated from six, 18-month-old Yanbian Yellow Cattle. The BSC were cultured for 96 h in differentiation medium containing 5 µM ciglitazone (CL), 10 µM ciglitazone (CM), or 20 µM ciglitazone (CH). Control (CON) BSC were cultured only in a differentiation medium (containing 2% horse serum). The presence of myogenin, desmin, and paired box 7 (Pax7) proteins was confirmed in the BSC by immunofluorescence staining. The CL, CM, and CH treatments produced higher concentrations of triacylglycerol and lipid droplet accumulation in myotubes than those of the CON treatment. Ciglitazone treatments significantly increased the relative expression of PPARγ, CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, fatty acid synthase, stearoyl-CoA desaturase, and perilipin 2. Ciglitazone treatments increased gene expression of Pax3 and Pax7 and decreased expression of myogenic differentiation-1, myogenin, myogenic regulatory factor-5, and myogenin-4 (p < 0.01). Adiponectin concentration caused by ciglitazone treatments was significantly greater than CON (p < 0.01). RNA sequencing showed that 281 differentially expressed genes (DEGs) were found in the treatments of ciglitazone. DEGs gene ontology (GO) analysis showed that the top 10 GO enrichment significantly changed the biological processes such as protein trimerization, negative regulation of cell proliferation, adipocytes differentiation, and cellular response to external stimulus. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that DEGs were involved in the p53 signaling pathway, PPAR signaling pathway, biosynthesis of amino acids, tumor necrosis factor signaling pathway, non-alcoholic fatty liver disease, PI3K-Akt signaling pathway, and Wnt signaling pathway. These results indicate that ciglitazone acts as PPARγ agonist, effectively increases the adiponectin concentration and adipogenic gene expression, and stimulates the conversion of BSC to adipocyte-like cells in the absence of adipocyte differentiation cocktail.

Molecular characterization of juvenile hormone signaling pathway-related genes in the brackish water flea Diaphanosoma celebensis (기수산 물벼룩의 유충 호르몬(Juvenile hormone) 신호전달경로 관련 유전자의 특성 분석)

  • Hayoung Cho;Jewon Yoo;Young-Mi Lee
    • Korean Journal of Environmental Biology
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    • v.40 no.3
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    • pp.255-266
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    • 2022
  • In crustaceans, molting is regulated by interactions between ecdysteroid and juvenile hormone (JH) signaling pathway-related genes. Unlike the ecdysteroid signaling pathway, little information on the role of JH signaling pathway-related genes in molting is available in zooplanktonic crustaceans. In this study, three genes (juvenile hormone acid O-methyltransferase (JHAMT), methoprene-tolerant (Met), and juvenile hormone epoxide hydrolase (JHEH)) which are involved in the synthesis, receptor-binding, and degradation of JH were identified using sequence and phylogenetic analysis in the brackish water flea, Diaphanosoma celebensis. Transcriptional changes in these genes during the molting cycle in D. celebensis were analyzed. Sequence and phylogenetic analysis revealed that these putative proteins may be functionally conserved along with those of insects and other crustaceans. In addition, the expression of the three genes was correlated with the molting cycle of D. celebensis, indicating that these genes may be involved in the synthesis and degradation of JH, resulting in normal molting. This study will provide information for a better understanding of the role of JH signaling pathway-related genes during the molting process in Cladocera.

SARS-CoV-2 mRNA Vaccine Elicits Sustained T Cell Responses Against the Omicron Variant in Adolescents

  • Sujin Choi;Sang-Hoon Kim;Mi Seon Han;Yoonsun Yoon;Yun-Kyung Kim;Hye-Kyung Cho;Ki Wook Yun;Seung Ha Song;Bin Ahn;Ye Kyung Kim;Sung Hwan Choi;Young June Choe;Heeji Lim;Eun Bee Choi;Kwangwook Kim;Seokhwan Hyeon;Hye Jung Lim;Byung-chul Kim;Yoo-kyoung Lee;Eun Hwa Choi;Eui-Cheol Shin;Hyunju Lee
    • IMMUNE NETWORK
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    • v.23 no.4
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    • pp.33.1-33.13
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    • 2023
  • Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been acknowledged as an effective mean of preventing infection and hospitalization. However, the emergence of highly transmissible SARS-CoV-2 variants of concern (VOCs) has led to substantial increase in infections among children and adolescents. Vaccine-induced immunity and longevity have not been well defined in this population. Therefore, we aimed to analyze humoral and cellular immune responses against ancestral and SARS-CoV-2 variants after two shots of the BNT162b2 vaccine in healthy adolescents. Although vaccination induced a robust increase of spike-specific binding Abs and neutralizing Abs against the ancestral and SARS-CoV-2 variants, the neutralizing activity against the Omicron variant was significantly low. On the contrary, vaccine-induced memory CD4+ T cells exhibited substantial responses against both ancestral and Omicron spike proteins. Notably, CD4+ T cell responses against both ancestral and Omicron strains were preserved at 3 months after two shots of the BNT162b2 vaccine without waning. Polyfunctionality of vaccine-induced memory T cells was also preserved in response to Omicron spike protein. The present findings characterize the protective immunity of vaccination for adolescents in the era of continuous emergence of variants/subvariants.

Inhibitory Effect of Purple Corn 'Seakso 1' Husk and Cob Extracts on Lipid Accumulation in Oleic Acid- Induced Non-Alcoholic Fatty Liver Disease HepG2 Model (올레산 유도 비알코올성 지방간세포에서 자색옥수수 색소 1호 포엽과 속대 추출물의 지질 축적 억제 효과)

  • Lee, Ki Yeon;Kim, Tae hee;Kim, Jai Eun;Bae, Son wha;Park, A-Reum;Lee, Hyo Young;Choi, Sun jin;Park, Jong yeol;Kwon, Soon bae;Kim, Hee Yeon
    • Journal of Food Hygiene and Safety
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    • v.35 no.1
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    • pp.93-101
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    • 2020
  • Seakso 1, a maize hybrid, was developed in 2008 by Gangwon Agricultural Research and Extension Services in Korea and registered in 2011. It is single-cross hybrid, semi-flint, deep-purple variety of corn, variety of are yellow, while the husks and cobs are purple. Due to the sensitivity of Seakso 1 to excess moisture after seeding, water supply should be carefully managed, and it should be harvested at a suitable time to obtain the highest anthocyanin content. This study investigated the hepatoprotective effect of Saekso 1 corn husk and cob extracts (EHCS) in oleic acid-induced non-alcoholic fatty liver disease (NAFLD) in HepG2 cells. EHCS showed a high level of lipid accumulation inhibiting effect. EHCS also suppressed triglyceride accumulation and inhibited expression of lipid marker genes, such as sterol regulatory element binding protein-1c (SREBP-1c) and sterol regulatory element binding protein-1a (SREBP-1a). Analysis by western blot of the expression of p-AMPK, p-SREBP1, PPARα, and FAS proteins showed that the incidence of SREBP1 protein, a major factor involved in lipid metabolism in the liver, has decreased significantly after treatment with the extracts. Moreover, the protein-induced expression of FAS, a major enzyme involved in the biosynthetic pathways of fatty acids, was decreased significantly in all concentrations. These results suggest that EHCS is a potent agent for the treatment of NAFLD.