• Title/Summary/Keyword: light signaling

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Interferon-gamma susceptibility of HL-60 cells, mononuclear cells of umbilical cord blood and bone marrow (HL-60 세포주, 제대혈 및 골수 단핵구 세포의 interferon-gamma에 대한 감수성에 관한 연구)

  • Cheong, Hee Jeong;Hong, Dae Sik;Kim, Sook Ja;Cheong, Jae Hwa;Lee, Joo Young;Lee, Nam Su;Park, Sung Kyu;Won, Jong Ho;Park, Hee Sook;Kim, Sung Il
    • IMMUNE NETWORK
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    • v.1 no.3
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    • pp.230-235
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    • 2001
  • Background: Finding of the regulation of various gene expression by cytokine including $IFN-{\gamma}$ in hematopoietic stem cell will light up the understanding of pathogenesis of aplastic anemia in various aspects. To study on aplastic anemia, however, we have to circumvent the difficulty of directly obtaining bone marrow stem cells from the patient. Therefore, we tried to find out a cell can replace the bone marrow stem cells for study on cell signaling pathway and regulation of gene expression by $IFN-{\gamma}$. Materials and Methods: HL-60 cells, of 20 ng/mL of $IFN-{\gamma}$. Total RNA was isolated from the cells and RT-PCR of the indoleamine 2,3-dioxygenase (IDO), $IFN-{\gamma}$, TNF-${\alpha}$, $MIP-1{\alpha}$, and $TGF-{\beta}2$ was carried out for the estimation of the gene expression. Results: $IFN-{\gamma}$ induced IDO gene expression of mononuclear cells from umbilical cord blood showed similar pattern as compared to that of bone marrow. Whether $INF-{\gamma}$ was treated or not, $TNF-{\alpha}$ was expressed in both mononuclear cells from umbilical cord blood and bone marrow. However, HL-60 cells showed different expression patterns. HL-60 cells would express neither IDO nor $TNF-{\alpha}$ even under the culture with 20ng/mL of $IFN-{\gamma}$. Conclusion: Our results showed bone marrow can be replaced with mononuclear cells from umbilical cord blood in the study on the relation between aplastic anemia and $IFN-{\gamma}$ including $IFN-{\gamma}$ cell signaling pathway.

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Research status of transcription factors involved in controlling gene expression by nitrate signaling in higher plants (고등식물의 질산시그널에 의한 유전자 발현제어 관련 전사인자의 연구현황)

  • Jung, Yu Jin;Park, Joung Soon;Go, Ji Yun;Lee, Hyo Ju;Kim, Jin Young;Lee, Ye Ji;Nam, Ki Hong;Cho, Yong-Gu;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
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    • v.48 no.3
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    • pp.124-130
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    • 2021
  • Nitrate is an important nutrient and signaling molecule in plants that modulates the expression of many genes and regulates plant growth. In this study, we cover the research status of transcription factors related to the control of gene expression by nitrate signaling in higher plants. Nitrate reductase is a key enzyme in nitrogen assimilation, as it catalyzes the nitrate-to-nitrite reduction process in plants. A variety of factors, including nitrate, light, metabolites, phytohormones, low temperature, and drought, modulate the expression levels of nitrate reductase genes and nitrate reductase activity, which is consistent with the physiological role if. Recently, several transcription factors controlling the expression of nitrate reductase genes have been identified in higher plants. NODULE-INCEPTION-Like Proteins (NLPs) are transcription factors responsible for the nitrate-inducible expression of nitrate reductase genes. Since NLPs also control the nitrate-inducible expression of genes encoding the nitrate transporter, nitrite transporter, and nitrite reductase, the expression levels of nitrate reduction pathway-associated genes are coordinately modulated by NLPs in response to nitrate. Understanding the function of nitrate in plants will be useful to create crops with low nitrogen use.

Antiapoptotic Effects Induced by Different Wavelengths of Ultraviolet Light

  • Ibuki, Yuko;Goto, Rensuke
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.485-487
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    • 2002
  • Cells receive signals for survival as well as death, and the balance between the two ultimately determines the fate of the cells. UV-triggered apoptotic signaling has been well documented, whereas UV-induced survival effects have received little attention. We have reported previously that UVB irradiation prevented apoptosis, which was partly dependent on activation of the phosphatidylinositol 3-kinase (PI3-kinase)/ Akt pathway. In this study, anti-apoptotic effects of UV with different wavelength ranges, UVA, UVB and UVC, were examined. NIH3T3 cells showed apoptotic cell death by detachment from the extracellular matrix under serum-free conditions, which was prevented by all wavelengths. However, the effect of UVA was less than those of UVB and UVC. Reduction of mitochondrial transmembrane potential and activation of caspase-9 and -3 were suppressed by all three wavelengths of UV, showing wavelength-dependent effects as mentioned above. The PI3-kinase inhibitor wortmannin partially inhibittrl the UVB and UVC-induced suppression of apoptosis, but not the inhibitoty effect of UVA. The Akt phosphotylation by UVB and UVC was completely inhibittrl by addition of wortmannin, but that by UVA was not P38 MAP kinase inhibitor SB203580 partially inhibited the UVB and UVC-induced suppression of apoptosis and Akt phosphotylation, and completely inhibited UVA-induced those. These results suggested the existence of two different survival pathways leading to suppression of apoptosis, one for UVA that is independent of the PI3-kinase/Akt pathway and dependent on p38 MAP kinase, and the other for UVB and UVC that is dependent on both pathways.

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Consensus channelome of dinoflagellates revealed by transcriptomic analysis sheds light on their physiology

  • Pozdnyakov, Ilya;Matantseva, Olga;Skarlato, Sergei
    • ALGAE
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    • v.36 no.4
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    • pp.315-326
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    • 2021
  • Ion channels are membrane protein complexes mediating passive ion flux across the cell membranes. Every organism has a certain set of ion channels that define its physiology. Dinoflagellates are ecologically important microorganisms characterized by effective physiological adaptability, which backs up their massive proliferations that often result in harmful blooms (red tides). In this study, we used a bioinformatics approach to identify homologs of known ion channels that belong to 36 ion channel families. We demonstrated that the versatility of the dinoflagellate physiology is underpinned by a high diversity of ion channels including homologs of animal and plant proteins, as well as channels unique to protists. The analysis of 27 transcriptomes allowed reconstructing a consensus ion channel repertoire (channelome) of dinoflagellates including the members of 31 ion channel families: inwardly-rectifying potassium channels, two-pore domain potassium channels, voltage-gated potassium channels (Kv), tandem Kv, cyclic nucleotide-binding domain-containing channels (CNBD), tandem CNBD, eukaryotic ionotropic glutamate receptors, large-conductance calcium-activated potassium channels, intermediate/small-conductance calcium-activated potassium channels, eukaryotic single-domain voltage-gated cation channels, transient receptor potential channels, two-pore domain calcium channels, four-domain voltage-gated cation channels, cation and anion Cys-loop receptors, small-conductivity mechanosensitive channels, large-conductivity mechanosensitive channels, voltage-gated proton channels, inositole-1,4,5-trisphosphate receptors, slow anion channels, aluminum-activated malate transporters and quick anion channels, mitochondrial calcium uniporters, voltage-dependent anion channels, vesicular chloride channels, ionotropic purinergic receptors, animal volage-insensitive cation channels, channelrhodopsins, bestrophins, voltage-gated chloride channels H+/Cl- exchangers, plant calcium-permeable mechanosensitive channels, and trimeric intracellular cation channels. Overall, dinoflagellates represent cells able to respond to physical and chemical stimuli utilizing a wide range of G-protein coupled receptors- and Ca2+-dependent signaling pathways. The applied approach not only shed light on the ion channel set in dinoflagellates, but also provided the information on possible molecular mechanisms underlying vital cellular processes dependent on the ion transport.

Reduced Expression of Limd1 in Ulcerative Oral Epithelium Associated with Tobacco and Areca Nut

  • Maiti, Guru Prasad;Ghosh, Amlan;Chatterjee, Ramdas;Roy, Anup;Sharp, Tyson V.;Roychoudhury, Susanta;Panda, Chinmay Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4341-4346
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    • 2012
  • Purpose: The aim of this study was to cast light on initiating molecular events associated with the development of premalignant oral lesions induced by tobacco and/or areca nut. Method: Immunohistochemical analyses of cell cycle regulatory proteins (LIMD1, RBSP3, p16, RB, phosphorylated RB, p53), EGFR and SH3GL2 (EGFR associated protein) were performed with inflammatory/ulcerative epithelium and adjacent hyperplastic/mild dysplastic lesions. Results: No change in expression of the proteins was seen in inflammatory epithelium. Reduced nuclear expression of LIMD1 was evident in ulcerative epithelium. In hyperplastic lesions, reduced expression of RBSP3, p16, SH3GL2 and overexpression of p-RB and EGFR were apparent. Reduced nuclear expression of p53 was observed in mild dysplastic lesions. Conclusion: Our data suggest that inactivation of LIMD1 in ulcerative epithelium might predispose the tissues to alterations of other cell cycle regulatory and EGFR signaling proteins needed for the development of premalignant oral lesions.

An inhibitory role of NEK6 in TGFβ/Smad signaling pathway

  • Zuo, Jie;Ma, Haijie;Cai, Hao;Wu, Yanhua;Jiang, Wei;Yu, Long
    • BMB Reports
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    • v.48 no.8
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    • pp.473-478
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    • 2015
  • The NEK6 (NIMA-related kinases 6) is reported to play po-tential roles in tumorigenesis. Although it is suggested to function in several cellular pathways, the underlying mechanism in tumorigenesis is still largely unknown. In the present study, we discovered interaction of NEK6 with Smad4, a key member of transforming growth factor beta (TGFβ) pathway. Over-expression of NEK6 in hepatocellular carcinoma (HCC) cell lines suppresses TGFβ-mediated transcription activity in a kinase activity-dependent manner. In addition, NEK6 suppresses the cell growth arrest induced by TGFβ. Mechanically, NEK6 blocks nuclear translocation of Smad4, which is essential for TGFβ function. Moreover, we identified that NEK6 could be regulated by TGFβ and hypoxia. Our study sheds new light on the roles of NEK6 in canonical TGFβ/Smad pathway and tum-origenesis. [BMB Reports 2015; 48(8): 473-478]

Detection of Hydrogen Peroxide in vitro and in vivo Using Peroxalate Chemiluminescent Micelles

  • Lee, Il-Jae;Hwang, On;Yoo, Dong-Hyuck;Khang, Gil-Son;Lee, Dong-Won
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2187-2192
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    • 2011
  • Hydrogen peroxide plays a key role as a second messenger in the normal cellular signaling but its overproduction has been implicated in various life-threatening diseases. Peroxalate chemiluminescence is the light emission from a three component reaction between peroxalate, hydrogen peroxide and fluorophores. It has proven great potential as a methodology to detect hydrogen peroxide in physiological environments because of its excellent sensitivity and specificity to hydrogen peroxide. We developed chemiluminescent micelles composed of amphiphilic polymers, peroxalate and fluorescent dyes to detect hydrogen peroxide at physiological concentrations. In this work, we studied the relationship between the chemiluminescence reactivity and stability of peroxalate by varying the substitutes on the aryl rings of peroxalate. Alkyl substitutes on the aryl ring of peroxalate increased the stability against water hydrolysis, but diminished the reactivity to hydrogen peroxide. Chemiluminescent micelles encapsulating diphenyl peroxalate showed significantly higher chemiluminescence intensity than the counterpart encapsulating dimethylphenyl or dipropylphenyl peroxalate. Diphenyl peroxalate-encapsulated micelles could detect hydrogen peroxide generated from macrophage cells stimulated by lipopolysaccharide (LPS) and image hydrogen peroxide generated during LPS-induced inflammatory responses in a mouse.

Autophagy in Cervical Cancer: An Emerging Therapeutic Target

  • Pandey, Saumya;Chandravati, Chandravati
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.4867-4871
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    • 2012
  • Cervical cancer is a leading cause of morbidity and mortality in women worldwide. Although the human papillomavirus (HPV) is considered the major causative agent of cervical cancer, yet the viral infection alone is not sufficient for cancer progression. The etiopathogenesis of cervical cancer is indeed complex; a precise understanding of the complex cellular/molecular mechanisms underlying the initiation, progression and/or prevention of the uterine cervix is therefore essential. Autophagy is emerging as an important biological mechanism in targeting human cancers, including cervical cancer. Furthermore, autophagy, a process of cytoplasm and cellular organelle degradation in lysosomes, has been implicated in homeostasis. Autophagic flux may vary depending on the cell/tissue type, thereby altering cell fate under stress conditions leading to cell survival and/or cell death. Autophagy may in turn govern tumor metastasis and subsequent carcinogenesis. Inflammation is a known hallmark of cancer. Vascular insufficiency in tumors, including cervical tissue, leads to depletion of glucose and/or oxygen perturbing the osmotic mileu causing extracellular acidosis in the tumor microenvironment that may eventually result in autophagy. Thus, targeted manipulation of complex autophagic signaling may prove to be an innovative strategy in identification of clinically relevant biomarkers in cervical cancer in the near future.

Performance Analysis of Buffer Aware Scheduling for Video Services in LTE Network

  • Lin, Meng-Hsien;Chen, Yen-Wen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3594-3610
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    • 2015
  • Recent advancements in broadband wireless communication technologies enable mobile users to receive video streaming services with various smart devices. The long term evolution (LTE) network provides high bandwidth and low latency for several emerging mobile applications. This paper proposes the buffer aware scheduling (BAS) approach to schedule the downlink video traffic in LTE network. The proposed BAS scheme applies the weighting function to heuristically adjust the scheduling priority by considering the buffer status and channel condition of UE so as to reduce the time that UE stays in the connected state without receiving data. Both of 1080P and 2160P resolution video streaming sources were applied for exhaustive simulations to examine the performance of the proposed scheme by comparing to that of the fair bandwidth (FB) and the best channel quality indicator (CQI) schemes. The simulation results indicate that the proposed BAS scheme not only achieves better performance in power saving, streaming delivery time, and throughput than the FB scheme while maintaining the similar performance as the best CQI scheme in light traffic load. Specifically, the proposed scheme reduces streaming delivery time and generates less signaling overhead than the best CQI scheme when the traffic load is heavy.

The Protein Kinase 2 Inhibitor CX-4945 Induces Autophagy in Human Cancer Cell Lines

  • Kim, Jiyeon;Park, Mikyung;Ryu, Byung Jun;Kim, Seong Hwan
    • Bulletin of the Korean Chemical Society
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    • v.35 no.10
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    • pp.2985-2989
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    • 2014
  • Autophagy is a self-digestion process in which intracellular structures are degraded in response to stress. Notably, prolonged autophagy leads to cell death. In this study, we investigated whether CX-4945, an orally available protein kinase 2 (CK2) inhibitor, induces autophagic cell death in human cervical cancer-derived HeLa cells and in human prostate cancer-derived LNCaP cells. CX-4945 treatment of both cell lines resulted in the formation of autophagosomes, in the conversion of microtubule-associated protein 1 light chain 3 (LC3), and in down-regulation of the Akt-mammalian target of rapamycin (mTOR)-p70 ribosomal protein S6 kinase (S6K) signaling cascade. Thus, pharmacologic inhibition of CK2 by CX-4945 induced autophagic cell death in human cancer cells by down-regulating Akt-mTOR-S6K. These results suggest that autophagy-inducing agents have potential as anti-cancer drugs.