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Sample records for nf-kappab transcription factors

  1. A novel form of the RelA nuclear factor kappaB subunit is induced by and forms a complex with the proto-oncogene c-Myc.

    Science.gov (United States)

    Chapman, Neil R; Webster, Gill A; Gillespie, Peter J; Wilson, Brian J; Crouch, Dorothy H; Perkins, Neil D

    2002-01-01

    Members of both Myc and nuclear factor kappaB (NF-kappaB) families of transcription factors are found overexpressed or inappropriately activated in many forms of human cancer. Furthermore, NF-kappaB can induce c-Myc gene expression, suggesting that the activities of these factors are functionally linked. We have discovered that both c-Myc and v-Myc can induce a previously undescribed, truncated form of the RelA(p65) NF-kappaB subunit, RelA(p37). RelA(p37) encodes the N-terminal DNA binding and dimerization domain of RelA(p65) and would be expected to function as a trans-dominant negative inhibitor of NF-kappaB. Surprisingly, we found that RelA(p37) no longer binds to kappaB elements. This result is explained, however, by the observation that RelA(p37), but not RelA(p65), forms a high-molecular-mass complex with c-Myc. These results demonstrate a previously unknown functional and physical interaction between RelA and c-Myc with many significant implications for our understanding of the role that both proteins play in the molecular events underlying tumourigenesis. PMID:12027803

  2. NF-kappaB and p53 are the dominant apoptosis-inducing transcription factors elicited by the HIV-1 envelope.

    Science.gov (United States)

    Perfettini, Jean-Luc; Roumier, Thomas; Castedo, Maria; Larochette, Nathanael; Boya, Patricia; Raynal, Brigitte; Lazar, Vladimir; Ciccosanti, Fabiola; Nardacci, Roberta; Penninger, Josef; Piacentini, Mauro; Kroemer, Guido

    2004-03-01

    The coculture of cells expressing the HIV-1 envelope glycoprotein complex (Env) with cells expressing CD4 results into cell fusion, deregulated mitosis, and subsequent cell death. Here, we show that NF-kappaB, p53, and AP1 are activated in Env-elicited apoptosis. The nuclear factor kappaB (NF-kappaB) super repressor had an antimitotic and antiapoptotic effect and prevented the Env-elicited phosphorylation of p53 on serine 15 and 46, as well as the activation of AP1. Transfection with dominant-negative p53 abolished apoptosis and AP1 activation. Signs of NF-kappaB and p53 activation were also detected in lymph node biopsies from HIV-1-infected individuals. Microarrays revealed that most (85%) of the transcriptional effects of HIV-1 Env were blocked by the p53 inhibitor pifithrin-alpha. Macroarrays led to the identification of several Env-elicited, p53-dependent proapoptotic transcripts, in particular Puma, a proapoptotic "BH3-only" protein from the Bcl-2 family known to activate Bax/Bak. Down modulation of Puma by antisense oligonucleotides, as well as RNA interference of Bax and Bak, prevented Env-induced apoptosis. HIV-1-infected primary lymphoblasts up-regulated Puma in vitro. Moreover, circulating CD4+ lymphocytes from untreated, HIV-1-infected donors contained enhanced amounts of Puma protein, and these elevated Puma levels dropped upon antiretroviral therapy. Altogether, these data indicate that NF-kappaB and p53 cooperate as the dominant proapoptotic transcription factors participating in HIV-1 infection.

  3. Transcription factor NF-kB as a potential biomarker for oxidative stress

    NARCIS (Netherlands)

    Berg, R. van den; Haenen, G.R.M.M.; Berg, H. van den; Bast, A.

    2001-01-01

    There is increasing interest in the involvement of transcription factors, such as of the transcription factor NF-κB (nuclear factor-κB), in the pathogenesis of various diseases. NF-κB is involved in the control of the transcription of a variety of cellular genes that regulate the inflammatory

  4. Phorbol-ester-induced activation of the NF-κB transcription factor involves dissociation of an apparently cytoplasmic NF-κB/inhibitor complex

    International Nuclear Information System (INIS)

    Baeuerle, P.A.; Lenardo, M.; Pierce, J.W.; Baltimore, D.

    1988-01-01

    There is increasing evidence that inducible transcription of genes is mediated through the induction of the activity of trans-acting protein factors. The NF-κB transcription factor provides a model system to study the posttranslational activation of a phorbol-ester-inducible transcription factor. The finding that NF-κB activity is undectable in subcellular fractions from unstimulated cells suggests that NF-κB exists as an inactive precursor. The authors showed that NF-κB is detectable in two different forms. After selective removal of endogenous NF-κB, they demonstrate the existence of a protein inhibitor in cytosolic fractions of unstimulated cells that is able in vitro to convert NF-κB into an inactive desoxycholate-dependent form. The data are consistent with a molecular mechanism of inducible gene expression by which an apparently cytoplasmic transcription factor-inhibitor complex is dissociated by the action of TPA-activated protein kinase C

  5. Transcription Factor NF-κB: An Update on Intervention Strategies.

    Science.gov (United States)

    Panday, Arvind; Inda, Maria Eugenia; Bagam, Prathyusha; Sahoo, Malaya K; Osorio, Diana; Batra, Sanjay

    2016-12-01

    The nuclear factor (NF)-κB family of transcription factors are ubiquitous and pleiotropic molecules that regulate the expression of more than 150 genes involved in a broad range of processes including inflammation, immunity, cell proliferation, differentiation, and survival. The chronic activation or dysregulation of NF-κB signaling is the central cause of pathogenesis in many disease conditions and, therefore, NF-κB is a major focus of therapeutic intervention. Because of this, understanding the relationship between NF-κB and the induction of various downstream signaling molecules is imperative. In this review, we provide an updated synopsis of the role of NF-κB in DNA repair and in various ailments including cardiovascular diseases, HIV infection, asthma, herpes simplex virus infection, chronic obstructive pulmonary disease, and cancer. Furthermore, we also discuss the specific targets for selective inhibitors and future therapeutic strategies.

  6. Is NF-kappaB a good target for cancer therapy? Hopes and pitfalls.

    Science.gov (United States)

    Baud, Véronique; Karin, Michael

    2009-01-01

    Nuclear factor kappaB (NF-kappaB) transcription factors have a key role in many physiological processes such as innate and adaptive immune responses, cell proliferation, cell death, and inflammation. It has become clear that aberrant regulation of NF-kappaB and the signalling pathways that control its activity are involved in cancer development and progression, as well as in resistance to chemotherapy and radiotherapy. This article discusses recent evidence from cancer genetics and cancer genome studies that support the involvement of NF-kappaB in human cancer, particularly in multiple myeloma. The therapeutic potential and benefit of targeting NF-kappaB in cancer, and the possible complications and pitfalls of such an approach, are explored.

  7. Overexpression of the transcription factor NF-YC9 confers abscisic acid hypersensitivity in Arabidopsis.

    Science.gov (United States)

    Bi, Chao; Ma, Yu; Wang, Xiao-Fang; Zhang, Da-Peng

    2017-11-01

    Nuclear factor Y (NF-Y) family proteins are involved in many developmental processes and responses to environmental cues in plants, but whether and how they regulate phytohormone abscisic acid (ABA) signaling need further studies. In the present study, we showed that over-expression of the NF-YC9 gene confers ABA hypersensitivity in both the early seedling growth and stomatal response, while down-regulation of NF-YC9 does not affect ABA response in these processes. We also showed that over-expression of the NF-YC9 gene confers salt and osmotic hypersensitivity in early seedling growth, which is likely to be directly associated with the ABA hypersensitivity. Further, we observed that NF-YC9 physically interacts with the ABA-responsive bZIP transcription factor ABA-INSENSITIVE5 (ABI5), and facilitates the function of ABI5 to bind and activate the promoter of a target gene EM6. Additionally, NF-YC9 up-regulates expression of the ABI5 gene in response to ABA. These findings show that NF-YC9 may be involved in ABA signaling as a positive regulator and likely functions redundantly together with other NF-YC members, and support the model that the NF-YC9 mediates ABA signaling via targeting to and aiding the ABA-responsive transcription factors such as ABI5.

  8. A Role for the NF-kb/Rel Transcription Factors in Human Breast Cancer

    National Research Council Canada - National Science Library

    Baldwin, Albert

    1998-01-01

    Human breast cancer is characterized by the inappropriate expression of growth factors, kinases and possibly certain transcription factors Our project has focused on the regulation of the NF-kB family...

  9. Eukaryotic Initiation Factor 4H Is under Transcriptional Control of p65/NF-κB

    Science.gov (United States)

    Fiume, Giuseppe; Rossi, Annalisa; de Laurentiis, Annamaria; Falcone, Cristina; Pisano, Antonio; Vecchio, Eleonora; Pontoriero, Marilena; Scala, Iris; Scialdone, Annarita; Masci, Francesca Fasanella; Mimmi, Selena; Palmieri, Camillo; Scala, Giuseppe; Quinto, Ileana

    2013-01-01

    Protein synthesis is mainly regulated at the initiation step, allowing the fast, reversible and spatial control of gene expression. Initiation of protein synthesis requires at least 13 translation initiation factors to assemble the 80S ribosomal initiation complex. Loss of translation control may result in cell malignant transformation. Here, we asked whether translational initiation factors could be regulated by NF-κB transcription factor, a major regulator of genes involved in cell proliferation, survival, and inflammatory response. We show that the p65 subunit of NF-κB activates the transcription of eIF4H gene, which is the regulatory subunit of eIF4A, the most relevant RNA helicase in translation initiation. The p65-dependent transcriptional activation of eIF4H increased the eIF4H protein content augmenting the rate of global protein synthesis. In this context, our results provide novel insights into protein synthesis regulation in response to NF-κB activation signalling, suggesting a transcription-translation coupled mechanism of control. PMID:23776612

  10. NF-κB Transcription Factor Role in Consolidation and Reconsolidation of Persistent Memories

    Directory of Open Access Journals (Sweden)

    Verónica ede la Fuente

    2015-09-01

    Full Text Available Transcriptional regulation is an important molecular process required for long-term neural plasticity and long-term memory formation. Thus, one main interest in molecular neuroscience in the last decades has been the identification of transcription factors that are involved in memory processes. Among them, the NF-κB family of transcription factors has gained interest due to a significant body of evidence that supports a key role of these proteins in synaptic plasticity and memory. In recent years, the interest was particularly reinforced because NF-κB was characterized as an important regulator of synaptogenesis. This function may be explained by its participation in synapse to nucleus communication, as well as a possible local role at the synapse. This review provides an overview of experimental work obtained in the last years, showing the essential role of this transcription factor in memory processes in different learning tasks in mammals. We focus the review on the consolidation and reconsolidation memory phases as well as on the regulation of immediate-early and late genes by epigenetic mechanisms that determine enduring forms of memories.

  11. Molecular evidence for the existence of lipopolysaccharide-induced TNF-alpha factor (LITAF) and Rel/NF-kB pathways in disk abalone (Haliotis discus discus).

    Science.gov (United States)

    De Zoysa, Mahanama; Nikapitiya, Chamilani; Oh, Chulhong; Whang, Ilson; Lee, Jae-Seong; Jung, Sung-Ju; Choi, Cheol Young; Lee, Jehee

    2010-01-01

    The lipopolysaccharide-induced TNF-alpha factor (LITAF) and Rel family nuclear factor kappaB (Rel/NF-kB) are two important transcription factors which play major roles in the regulating inflammatory cytokine, apoptosis and immune related genes. Here, we report the discovery of disk abalone LITAF (AbLITAF) and Rel/NF-kB (AbRel/NF-kB) homologues and their immune responses. Full-length cDNA of AbLITAF consists of 441 bp open reading frame (ORF) that translates into putative peptide of 147 aa. Analysis of AbLITAF sequence showed it has characteristic LITAF (Zn(+2)) binding domain with two CXXC motifs. Phylogenetic analysis results further revealed that AbLITAF is a member of LITAF family. AbRel/NF-kB is 584 aa protein that contains several characteristic motifs including Rel homology domain (RHD), Rel protein signature, DNA binding motif, nuclear localization signal (NLS) and transcription factor immunoglobulin - like fold (TIG) similar to their invertebrate and vertebrate counterparts. Tissue specific analysis results showed that both AbLITAF and AbRel/NF-kB mRNA was expressed ubiquitously in all selected tissues in constitutive manner. However, constitutive expression of AbLITAF was higher than AbRel/NF-kB in all tissues except mantle. Upon immune challenge by bacteria (Vibrio alginolyticus, Vibrio parahemolyticus and Lysteria monocytogenes) and viral hemoragic septicemia virus (VHSV), AbLITAF showed the significant up-regulation in gills while AbRel/NF-kB transcription was not change significantly. Based on transcriptional response against immune challenge, we could suggest that regulation of TNF-alpha expression may have occurred mainly by LITAF activation rather than NF-kB in disk abalone. The cumulative data from other molluscs and our data with reference to TNF-alpha, LITAF and Rel/NF-kB from disk abalone provide strong evidence that LITAF and NF-kB are independent pathways likely to occur throughout the Phylum mollusca. 2010 Elsevier Ltd. All rights reserved.

  12. Memory extinction entails the inhibition of the transcription factor NF-kappaB.

    Directory of Open Access Journals (Sweden)

    Emiliano Merlo

    Full Text Available In contextual memories, an association between a positive or negative reinforcement and the contextual cues where the reinforcement occurs is formed. The re-exposure to the context without reinforcement can lead to memory extinction or reconsolidation, depending on the number of events or duration of a single event of context re-exposure. Extinction involves the temporary waning of the previously acquired conditioned response. The molecular processes underlying extinction and the mechanisms which determine if memory will reconsolidate or extinguish after retrieval are not well characterized, particularly the role of transcription factors and gene expression. Here we studied the participation of a transcription factor, NF-kappaB, in memory extinction. In the crab context-signal memory, the activation of NF-kappaB plays a critical role in consolidation and reconsolidation, memory processes that are well characterized in this model. The administration of a NF-kappaB inhibitor, sulfasalazine prior to extinction session impeded spontaneous recovery. Moreover, reinstatement experiments showed that the original memory was not affected and that NF-kappaB inhibition by sulfasalazine impaired spontaneous recovery strengthening the ongoing memory extinction process. Interestingly, in animals with fully consolidated memory, a brief re-exposure to the training context induced neuronal NF-kappaB activation and reconsolidation, while prolonged re-exposure induced NF-kappaB inhibition and memory extinction. These data constitutes a novel insight into the molecular mechanisms involved in the switch between memory reconsolidation and extinction. Moreover, we propose the inhibition of NF-kappaB as the engaged mechanism underlying extinction, supporting a novel approach for the pharmacological enhancement of this memory process. The accurate description of the molecular mechanisms that support memory extinction is potentially useful for developing new strategies

  13. Copine-I: Modulator of NF-kappa B Transcription and Prostate Cancer Survival

    National Research Council Canada - National Science Library

    Mayo, Marty W; Creutz, Carl

    2008-01-01

    The purpose of our studies is to elucidate how Copine-I antagonizes NF-.B transcription. Nuclear factor-.B (NF-.B) is a dynamic transcription factor that regulates important biological processes involved in cancer initiation and progression...

  14. Transforming growth factor-beta 1 (TGF-beta1) promotes IL-2 mRNA expression through the up-regulation of NF-kappaB, AP-1 and NF-AT in EL4 cells.

    Science.gov (United States)

    Han, S H; Yea, S S; Jeon, Y J; Yang, K H; Kaminski, N E

    1998-12-01

    Transforming growth factor beta1 (TGF-beta1) has been previously shown to modulate interleukin 2 (IL-2) secretion by activated T-cells. In the present studies, we determined that TGF-beta1 induced IL-2 mRNA expression in the murine T-cell line EL4, in the absence of other stimuli. IL-2 mRNA expression was significantly induced by TGF-beta1 (0.1-1 ng/ml) over a relatively narrow concentration range, which led to the induction of IL-2 secretion. Under identical condition, we examined the effect of TGF-beta1 on the activity of nuclear factor AT (NF-AT), nuclear factor kappaB (NF-kappaB), activator protein-1 (AP-1) and octamer, all of which contribute to the regulation of IL-2 gene expression. Electrophoretic mobility shift assays showed that TGF-beta1 markedly increased NF-AT, NF-kappaB and AP-1 binding to their respective cognate DNA binding sites, whereas octamer binding remained constant, as compared with untreated cells. Employing a reporter gene expression system with p(NF-kappaB)3-CAT, p(NF-AT)3-CAT and p(AP-1)3-CAT, TGF-beta1 treatment of transfected EL4 cells induced a dose-related increase in chloramphenicol acetyltransferase activity that correlated well with the DNA binding profile found in the electrophoretic mobility shift assay studies. These results show that TGF-beta1, in the absence of any additional stimuli, up-regulates the activity of key transcription factors involved in IL-2 gene expression, including NF-AT, NF-kappaB and AP-1, to help promote IL-2 mRNA expression by EL4 cells.

  15. Direct non transcriptional role of NF-Y in DNA replication.

    Science.gov (United States)

    Benatti, Paolo; Belluti, Silvia; Miotto, Benoit; Neusiedler, Julia; Dolfini, Diletta; Drac, Marjorie; Basile, Valentina; Schwob, Etienne; Mantovani, Roberto; Blow, J Julian; Imbriano, Carol

    2016-04-01

    NF-Y is a heterotrimeric transcription factor, which plays a pioneer role in the transcriptional control of promoters containing the CCAAT-box, among which genes involved in cell cycle regulation, apoptosis and DNA damage response. The knock-down of the sequence-specific subunit NF-YA triggers defects in S-phase progression, which lead to apoptotic cell death. Here, we report that NF-Y has a critical function in DNA replication progression, independent from its transcriptional activity. NF-YA colocalizes with early DNA replication factories, its depletion affects the loading of replisome proteins to DNA, among which Cdc45, and delays the passage from early to middle-late S phase. Molecular combing experiments are consistent with a role for NF-Y in the control of fork progression. Finally, we unambiguously demonstrate a direct non-transcriptional role of NF-Y in the overall efficiency of DNA replication, specifically in the DNA elongation process, using a Xenopus cell-free system. Our findings broaden the activity of NF-Y on a DNA metabolism other than transcription, supporting the existence of specific TFs required for proper and efficient DNA replication. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  16. MicroRNAs control transcription factor NF-kB (p65) expression in human ovarian cells.

    Science.gov (United States)

    Sirotkin, Alexander V; Alexa, Richard; Kišová, Gabriela; Harrath, Abdel Halim; Alwasel, Saleh; Ovcharenko, Dmitriy; Mlynček, Miloš

    2015-05-01

    MicroRNAs (miRNAs) are known to influence ovarian cell proliferation, apoptosis and hormone release, but it remains unknown whether miRNAs affect ovarian functions via transcription factors. We examined the effect of miRNAs on nuclear factor-κappaB (NF-kB) (p65) expression in human ovarian luteinized granulosa cells. We transfected cultured primary human ovarian luteinized granulosa cells with 80 different constructs encoding human pre-miRNAs and then evaluated NF-kB (p65) expression (percentage of cells containing p65) by immunocytochemistry. We found that 21 of the constructs stimulated NF-kB (p65) expression and 18 of the constructs inhibited NF-kB (p65) expression. This is the first direct demonstration that miRNAs affect NF-kB (p65) expression and the first genome-scale miRNA screen to identify upregulation and downregulation of NF-kB accumulation by miRNAs in the ovary. Novel miRNAs that affect the NF-kB signalling pathway could be useful for the control of NF-kB-dependent reproductive processes and the treatment of NF-kB-dependent reproductive disorders.

  17. Hepatitis C Virus NS3 Mediated Microglial Inflammation via TLR2/TLR6 MyD88/NF-κB Pathway and Toll Like Receptor Ligand Treatment Furnished Immune Tolerance.

    Directory of Open Access Journals (Sweden)

    Ayilam Ramachandran Rajalakshmy

    Full Text Available Recent evidence suggests the neurotrophic potential of hepatitis C virus (HCV. HCV NS3 protein is one of the potent antigens of this virus mediating inflammatory response in different cell types. Microglia being the immune surveillance cells in the central nervous system (CNS, the inflammatory potential of NS3 on microglia was studied. Role of toll like receptor (TLR ligands Pam2CSK3 and Pam3CSK4 in controlling the NS3 mediated microglial inflammation was studied using microglial cell line CHME3.IL (Interleukin-8, IL-6, TNF-α (Tumor nicrosis factor alpha and IL-1β gene expressions were measured by semi quantitative RT-PCR (reverse transcription-PCR. ELISA was performed to detect IL-8, IL-6, TNF-α, IL-1β and IL-10 secretion. FACS (Flourescent activated cell sorting was performed to quantify TLR1, TLR2, TLR6, MyD88 (Myeloid differntiation factor 88, IkB-α (I kappaB alpha and pNF-κB (phosphorylated nuclear factor kappaB expression. Immunofluorescence staining was performed for MyD88, TLR6 and NF-κB (Nuclear factor kappaB. Student's t-test or One way analysis of variance with Bonferoni post hoc test was performed and p < 0.05 was considered significant.Microglia responded to NS3 by secreting IL-8, IL-6, TNF-α and IL-1β via TLR2 or TLR6 mediated MyD88/NF-κB pathway. Transcription factor NF-κB was involved in activating the cytokine gene expression and the resultant inflammatory response was controlled by NF-κB inhibitor, Ro106-9920, which is known to down regulate pro-inflammatory cytokine secretion. Activation of the microglia by TLR agonists Pam3CSK4 and Pam2CSK4 induced immune tolerance against NS3. TLR ligand treatment significantly down regulated pro-inflammatory cytokine secretion in the microglia. IL-10 secretion was suggested as the possible mechanism by which TLR agonists induced immune tolerance. NS3 as such was not capable of self-inducing immune tolerance in microglia.In conclusion, NS3 protein was capable of activating

  18. Inhibitory effects of curcumin and capsaicin on phorbol ester-induced activation of eukaryotic transcription factors, NF-kappaB and AP-1.

    Science.gov (United States)

    Surh, Y J; Han, S S; Keum, Y S; Seo, H J; Lee, S S

    2000-01-01

    Recently, considerable attention has been focused on identifying dietary and medicinal phytochemicals that can inhibit, retard or reverse the multi-stage carcinogenesis. Spices and herbs contain phenolic substances with potent antioxidative and chemopreventive properties. Curcumin, a yellow colouring agent from turmeric and capsaicin, a pungent principle of red pepper exhibit profound anticarcinogenic and antimutagenic activities. Two well-defined eukaryotic transcription factors, nuclear factor-kappa B (NF-kappaB) and activator protein 1 (AP-1) have been implicated in pathogenesis of many human diseases including cancer. These transcription factors are known to be activated by a wide array of external stimuli, such as tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), tumor necrosis factor, reactive oxygen species, bacterial lipopolysaccharide, and ultraviolet. In the present study, we found that topical application of TPA onto dorsal skin of female ICR mice resulted in marked activation of epidermal NF-kappaB and AP-1. Curcumin and capsaicin, when topically applied prior to TPA, significantly attenuated TPA-induced activation of each transcription factor in mouse skin. Likewise, both compounds inhibited NF-kappaB and AP-1 activation in cultured human promyelocytic leukemia (HL-60) cells stimulated with TPA. Based on these findings, it is likely that curcumin and capsaicin exert anti-tumor promotional effects through suppression of the tumor promoter-induced activation of transcription factors, NF-kappaB and AP-1.

  19. Diarctigenin, a lignan constituent from Arctium lappa, down-regulated zymosan-induced transcription of inflammatory genes through suppression of DNA binding ability of nuclear factor-kappaB in macrophages.

    Science.gov (United States)

    Kim, Byung Hak; Hong, Seong Su; Kwon, Soon Woo; Lee, Hwa Young; Sung, Hyeran; Lee, In-Jeong; Hwang, Bang Yeon; Song, Sukgil; Lee, Chong-Kil; Chung, Daehyun; Ahn, Byeongwoo; Nam, Sang-Yoon; Han, Sang-Bae; Kim, Youngsoo

    2008-11-01

    Diarctigenin was previously isolated as an inhibitor of nitric oxide (NO) production in macrophages from the seeds of Arctium lappa used as an alternative medicine for the treatment of inflammatory disorders. However, little is known about the molecular basis of these effects. Here, we demonstrated that diarctigenin inhibited the production of NO, prostaglandin E(2), tumor necrosis factor-alpha, and interleukin (IL)-1beta and IL-6 with IC(50) values of 6 to 12 miciroM in zymosan- or lipopolysaccharide-(LPS) activated macrophages. Diarctigenin attenuated zymosan-induced mRNA synthesis of inducible NO synthase (iNOS) and also inhibited promoter activities of iNOS and cytokine genes in the cells. Because nuclear factor (NF)-kappaB plays a pivotal role in inflammatory gene transcription, we next investigated the effect of diarctigenin on NF-kappaB activation. Diarctigenin inhibited the transcriptional activity and DNA binding ability of NF-kappaB in zymosan-activated macrophages but did not affect the degradation and phosphorylation of inhibitory kappaB (IkappaB) proteins. Moreover, diarctigenin suppressed expression vector NF-kappaB p65-elicited NF-kappaB activation and also iNOS promoter activity, indicating that the compound could directly target an NF-kappa-activating signal cascade downstream of IkappaB degradation and inhibit NF-kappaB-regulated iNOS expression. Diarctigenin also inhibited the in vitro DNA binding ability of NF-kappaB but did not affect the nuclear import of NF-kappaB p65 in the cells. Taken together, diarctigenin down-regulated zymosan- or LPS-induced inflammatory gene transcription in macrophages, which was due to direct inhibition of the DNA binding ability of NF-kappaB. Finally, this study provides a pharmacological potential of diarctigenin in the NF-kappaB-associated inflammatory disorders.

  20. Regulation of Neph3 gene in podocytes - key roles of transcription factors NF-kappaB and Sp1

    LENUS (Irish Health Repository)

    Ristola, Mervi

    2009-08-24

    Abstract Background Neph3 (filtrin) is expressed in the glomerular podocytes where it localizes at the specialized cell adhesion structures of the foot processes called slit diaphragms which form the outermost layer of the glomerular filtration barrier. Neph3 protein shows homology and structural similarity to Neph1, Neph2 and nephrin, which all are crucial for maintaining the normal glomerular ultrafiltration function. The exact function of Neph3 in the kidney is not known but we have previously shown that the level of Neph3 mRNA is decreased in proteinuric diseases. This suggests that Neph3 may play a role in the pathogenesis of kidney damage, and emphasizes the need to analyze the regulatory mechanisms of Neph3 gene. In this study we investigated the transcriptional regulation of Neph3 gene by identifying transcription factors that control Neph3 expression. Results We cloned and characterized approximately 5 kb fragment upstream of the Neph3 gene. Neph3 proximal promoter near the transcription start site was found to be devoid of TATA and CAAT boxes, but to contain a highly GC-rich area. Using promoter reporter gene constructs, we localized the main activating regulatory region of Neph3 gene in its proximal promoter region from -105 to -57. Within this region, putative transcription factor binding sites for NF-κB and Sp1 were found by computational analysis. Mutational screening indicated that NF-κB and Sp1 response elements are essential for the basal transcriptional activity of the Neph3 promoter. Co-transfection studies further showed that NF-κB and Sp1 regulate Neph3 promoter activity. In addition, overexpression of NF-κB increased endogenous Neph3 gene expression. Chromatin immunoprecipitation assay using cultured human podocytes demonstrated that both NF-κB and Sp1 interact with the Neph3 promoter. Conclusion Our results show that NF-κB and Sp1 are key regulators of Neph3 expression at the basal level in podocytes, therefore providing new insight

  1. Mitochondria mediate tumor necrosis factor-alpha/NF-kappaB signaling in skeletal muscle myotubes

    Science.gov (United States)

    Li, Y. P.; Atkins, C. M.; Sweatt, J. D.; Reid, M. B.; Hamilton, S. L. (Principal Investigator)

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is implicated in muscle atrophy and weakness associated with a variety of chronic diseases. Recently, we reported that TNF-alpha directly induces muscle protein degradation in differentiated skeletal muscle myotubes, where it rapidly activates nuclear factor kappaB (NF-kappaB). We also have found that protein loss induced by TNF-alpha is NF-kappaB dependent. In the present study, we analyzed the signaling pathway by which TNF-alpha activates NF-kappaB in myotubes differentiated from C2C12 and rat primary myoblasts. We found that activation of NF-kappaB by TNF-alpha was blocked by rotenone or amytal, inhibitors of complex I of the mitochondrial respiratory chain. On the other hand, antimycin A, an inhibitor of complex III, enhanced TNF-alpha activation of NK-kappaB. These results suggest a key role of mitochondria-derived reactive oxygen species (ROS) in mediating NF-kappaB activation in muscle. In addition, we found that TNF-alpha stimulated protein kinase C (PKC) activity. However, other signal transduction mediators including ceramide, Ca2+, phospholipase A2 (PLA2), and nitric oxide (NO) do not appear to be involved in the activation of NF-kappaB.

  2. RelA NF-κB subunit activation as a therapeutic target in diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Zhang, Mingzhi; Xu-Monette, Zijun Y; Li, Ling

    2016-01-01

    It has been well established that nuclear factor kappa-B (NF-κB) activation is important for tumor cell growth and survival. RelA/p65 and p50 are the most common NF-kB subunits and involved in the classical NF-kB pathway. However, the prognostic and biological significance of RelA/p65 is equivoca...

  3. Activation of AMP-activated protein kinase by kainic acid mediates brain-derived neurotrophic factor expression through a NF-kappaB dependent mechanism in C6 glioma cells

    International Nuclear Information System (INIS)

    Yoon, Hana; Oh, Young Taek; Lee, Jung Yeon; Choi, Ji Hyun; Lee, Ju Hie; Baik, Hyung Hwan; Kim, Sung Soo; Choe, Wonchae; Yoon, Kyung-Sik; Ha, Joohun; Kang, Insug

    2008-01-01

    AMP-activated protein kinase (AMPK) is a key regulator of energy homeostasis. Kainic acid (KA), a prototype excitotoxin is known to induce brain-derived neurotrophic factor (BDNF) in brain. In this study, we examined the role of AMPK in KA-induced BDNF expression in C6 glioma cells. We showed that KA and KA receptor agonist induced activation of AMPK and KA-induced AMPK activation was blocked by inhibition of Ca 2+ /calmodulin-dependent protein kinase kinase (CaMKK) β. We then showed that inhibition of AMPK by compound C, a selective inhibitor of AMPK, or small interfering RNA of AMPKα1 blocked KA-induced BDNF mRNA and protein expression. Inhibition of AMPK blocked KA-induced phosphorylation of CaMKII and I kappaB kinase (IKK) in C6 cells. Finally, we showed that inhibition of AMPK reduced DNA binding and transcriptional activation of nuclear factor-kappaB (NF-κB) in KA-treated cells. These results suggest that AMPK mediates KA-induced BDNF expression by regulating NF-κB activation

  4. Noisy transcription factor NF-¿B oscillations stabilize and sensitize cytokine signaling in space

    DEFF Research Database (Denmark)

    Gangstad, S.W.; Feldager, C.W.; Juul, Jeppe Søgaard

    2013-01-01

    NF-¿B is a major transcription factor mediating inflammatory response. In response to a pro-inflammatory stimulus, it exhibits a characteristic response - a pulse followed by noisy oscillations in concentrations of considerably smaller amplitude. NF-¿B is an important mediator of cellular...... amplitude has not been addressed. We use a cellular automaton model to address these issues in the context of spatially distributed communicating cells. We find that noisy secondary oscillations stabilize concentric wave patterns, thus improving signal quality. Furthermore, both lower secondary amplitude...... as well as noise in the oscillation period might be working against chronic inflammation, the state of self-sustained and stimulus-independent excitations. Our findings suggest that the characteristic irregular secondary oscillations of lower amplitude are not accidental. On the contrary, they might have...

  5. NF-Y loss triggers p53 stabilization and apoptosis in HPV18-positive cells by affecting E6 transcription.

    Science.gov (United States)

    Benatti, Paolo; Basile, Valentina; Dolfini, Diletta; Belluti, Silvia; Tomei, Margherita; Imbriano, Carol

    2016-07-19

    The expression of the high risk HPV18 E6 and E7 oncogenic proteins induces the transformation of epithelial cells, through the disruption of p53 and Rb function. The binding of cellular transcription factors to cis-regulatory elements in the viral Upstream Regulatory Region (URR) stimulates E6/E7 transcription. Here, we demonstrate that the CCAAT-transcription factor NF-Y binds to a non-canonical motif within the URR and activates viral gene expression. In addition, NF-Y indirectly up-regulates HPV18 transcription through the transactivation of multiple cellular transcription factors. NF-YA depletion inhibits the expression of E6 and E7 genes and re-establishes functional p53. The activation of p53 target genes in turn leads to apoptotic cell death. Finally, we show that NF-YA loss sensitizes HPV18-positive cells toward the DNA damaging agent Doxorubicin, via p53-mediated transcriptional response.

  6. Mycobacterium leprae induces NF-κB-dependent transcription repression in human Schwann cells

    International Nuclear Information System (INIS)

    Pereira, Renata M.S.; Calegari-Silva, Teresa Cristina; Hernandez, Maristela O.; Saliba, Alessandra M.; Redner, Paulo; Pessolani, Maria Cristina V.; Sarno, Euzenir N.; Sampaio, Elizabeth P.; Lopes, Ulisses G.

    2005-01-01

    Mycobacterium leprae, the causative agent of leprosy, invades peripheral nerve Schwann cells, resulting in deformities associated with this disease. NF-κB is an important transcription factor involved in the regulation of host immune antimicrobial responses. We aimed in this work to investigate NF-κB signaling pathways in the human ST88-14 Schwannoma cell line infected with M. leprae. Gel shift and supershift assays indicate that two NF-κB dimers, p65/p50 and p50/p50, translocate to the nucleus in Schwann cells treated with lethally irradiated M. leprae. Consistent with p65/p50 and p50/p50 activation, we observed IκB-α degradation and reduction of p105 levels. The nuclear translocation of p50/p50 complex due to M. leprae treatment correlated with repression of NF-κB-driven transcription induced by TNF-α. Moreover, thalidomide inhibited p50 homodimer nuclear translocation induced by M. leprae and consequently rescues Schwann cells from NF-κB-dependent transcriptional repression. Here, we report for the first time that M. leprae induces NF-κB activation in Schwann cells and thalidomide is able to modulate this activation

  7. A Key Role for NF-κB Transcription Factor c-Rel in T-Lymphocyte-Differentiation and Effector Functions

    Directory of Open Access Journals (Sweden)

    Alexander Visekruna

    2012-01-01

    Full Text Available The transcription factors of the Rel/NF-κB family function as key regulators of innate and adoptive immunity. Tightly and temporally controlled activation of NF-κB-signalling pathways ensures prevention of harmful immune cell dysregulation, whereas a loss of control leads to pathological conditions such as severe inflammation, autoimmune disease, and inflammation-associated oncogenesis. Five family members have been identified in mammals: RelA (p65, c-Rel, RelB, and the precursor proteins NF-κB1 (p105 and NF-κB2 (p100, that are processed into p50 and p52, respectively. While RelA-containing dimers are present in most cell types, c-Rel complexes are predominately found in cells of hematopoietic origin. In T-cell lymphocytes, certain genes essential for immune function such as Il2 and Foxp3 are directly regulated by c-Rel. Additionally, c-Rel-dependent IL-12 and IL-23 transcription by macrophages and dendritic cells is crucial for T-cell differentiation and effector functions. Accordingly, c-Rel expression in T cells and antigen-presenting cells (APCs controls a delicate balance between tolerance and immunity. This review gives a selective overview on recent progress in understanding of diverse roles of c-Rel in regulating adaptive immunity.

  8. Chalepin: A Compound from Ruta angustifolia L. Pers Exhibits Cell Cycle Arrest at S phase, Suppresses Nuclear Factor-Kappa B (NF-κB) Pathway, Signal Transducer and Activation of Transcription 3 (STAT3) Phosphorylation and Extrinsic Apoptotic Pathway in Non-small Cell Lung Cancer Carcinoma (A549).

    Science.gov (United States)

    Richardson, Jaime Stella Moses; Aminudin, Norhaniza; Abd Malek, Sri Nurestri

    2017-10-01

    transducer and activation of transcription 3, and extrinsic apoptotic pathway and also its ability to arrest cell cycle in S phase. This compound was from the leaves of Ruta angustifolia L. Pers. It provides new insight on the ability of this plant in suppressing certain cancers, especially the nonsmall cell lung carcinoma according to this study. Abbreviations used: °C: Degree Celsius, ANOVA: Analysis of variance, ATCC: American Type Culture Collection, BCL-2: B-Cell CLL/Lymphoma 2, Bcl-xL: B-cell lymphoma extra-large, BH3: Bcl-2 homology 3, BID: BH3-interacting domain death agonist, BIR: Baculovirus inhibitor of apoptosis protein repeat, Caspases: Cysteinyl aspartate-specific proteases, CDK: Cyclin-dependent kinase, CO 2 : Carbon dioxide, CST: Cell signaling technologies, DISC: Death-inducing signaling complex, DMSO: Dimethyl sulfoxide, DNA: Deoxyribonucleic acid, DR4: Death receptor 4, DR5: Death receptor 5, E1a: Adenovirus early region 1A, ECL: Enhanced chemiluminescence, EDTA: Ethylenediaminetetraacetic acid, ELISA: Enzyme-linked immunosorbent assay, etc.: Etcetera, FADD: Fas-associated protein with death domain, FBS: Fetal bovine serum, FITC: Fluorescein isothiocyanate, G1: Gap 1, G2: Gap 2, HPLC: High-performance liquid chromatography, HRP: Horseradish peroxidase, IAPs: Inhibitor of apoptosis proteins, IC50: Inhibitory concentration at half maximal inhibitory, IKK-α: Inhibitor of nuclear factor kappa-B kinase subunit alpha, IKK-β: Inhibitor of nuclear factor kappa-B kinase subunit beta, IKK-γ: Inhibitor of nuclear factor kappa-B kinase subunit gamma, IKK: IκB kinase, IkBα: Nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha, m: Meter, M: Mitotic, mm: Millimeter, mRNA: Messenger ribonucleic acid, NaCl: Sodium chloride, NaVO4: Sodium orthovanadate, NEMO: NF-Kappa-B essential modulator, NF-κB: Nuclear factor kappa-light chain-enhancer of activated B cells, NSCLC: Nonsmall cell lung carcinoma, PBS: Phosphate buffered saline, PGE2

  9. Lentiviral-mediated targeted NF-kappaB blockade in dorsal spinal cord glia attenuates sciatic nerve injury-induced neuropathic pain in the rat.

    Science.gov (United States)

    Meunier, Alice; Latrémolière, Alban; Dominguez, Elisa; Mauborgne, Annie; Philippe, Stéphanie; Hamon, Michel; Mallet, Jacques; Benoliel, Jean-Jacques; Pohl, Michel

    2007-04-01

    Neuropathic pain developing after peripheral nerve injury is associated with altered neuronal and glial cell functions in the spinal cord. Activated glia produces algogenic mediators, exacerbating pain. Among the different intracellular pathways possibly involved in the modified glial function, the nuclear factor kappaB (NF-kappaB) system is of particular interest, as numerous genes encoding inflammation- and pain-related molecules are controlled by this transcription factor. NF-kappaB is a pleiotropic factor also involved in central nervous system homeostasy. To study its role in chronic pain, it is thus essential to inhibit the NF-kappaB pathway selectively in activated spinal glial cells. Here, we show that when restricted to spinal cord and targeted to glial cells, lentiviral vector-mediated delivery of NF-kappaB super- repressor IkappaBalpha resulted in an inhibition of the NF-kappaB pathway activated in the rat spinal cord after sciatic nerve injury (chronic constriction injury, CCI). Concomitantly, IkappaBalpha overproduction prevented the enhanced expression of interleukin-6 and of inducible nitric oxide synthase associated with chronic constriction injury and resulted in prolonged antihyperalgesic and antiallodynic effects. These data show that targeted blockade of NF-kappaB activity in spinal glia efficiently alleviates pain behavior in CCI rats, demonstrating the active participation of the glial NF-kappaB pathway in the development of neuropathic pain after peripheral nerve injury.

  10. Regulation of NF-{kappa}B activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Spilsbury, Alison [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom); Vauzour, David; Spencer, Jeremy P.E. [Molecular Nutrition Group, Centre for Integrative Neuroscience and Neurodynamics, School of Chemistry, Food and Pharmacy, University of Reading, Reading RG6 6AP (United Kingdom); Rattray, Marcus, E-mail: m.a.n.rattray@reading.ac.uk [Reading School of Pharmacy, University of Reading, Reading RG6 6UB (United Kingdom)

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer We tested the hypothesis that low concentrations of flavonoids inhibit NF-{kappa}B in astrocytes. Black-Right-Pointing-Pointer Primary cultured astrocytes possess a functional {kappa}B-system, measured using luciferase assays. Black-Right-Pointing-Pointer Seven flavonoids (100 nM-1 {mu}M) failed to reduce NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer Four flavonoids (100 nM-1 {mu}M) failed to reduce TNFa-stimulated NF-{kappa}B activity in astrocytes. Black-Right-Pointing-Pointer (-)-Epicatechin did not regulate nuclear translocation of the NF-{kappa}B subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Sustained activation of nuclear transcription factor {kappa}B (NF-{kappa}B) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-{kappa}B signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNF{alpha}, 150 ng/ml) increased NF-{kappa}B-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative I{kappa}B{alpha} construct. In addition, TNF{alpha} increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-{kappa}B activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((-)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1-1 {mu}M) for 18 h. None of the flavonoids modulated constitutive or

  11. Nuclear IL-33 is a transcriptional regulator of NF-{kappa}B p65 and induces endothelial cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yeon-Sook; Park, Jeong Ae; Kim, Jihye; Rho, Seung-Sik; Park, Hyojin [Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Young-Myeong [Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon (Korea, Republic of); Kwon, Young-Guen, E-mail: ygkwon@yonsei.ac.kr [Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2012-05-04

    Highlights: Black-Right-Pointing-Pointer IL-33 as nuclear factor regulated expression of ICAM-1 and VCAM-1. Black-Right-Pointing-Pointer Nuclear IL-33 increased the transcription of NF-{kappa}B p65 by binding to the p65 promoter. Black-Right-Pointing-Pointer Nuclear IL-33 controls NF-{kappa}B-dependent inflammatory responses. -- Abstract: Interleukin (IL)-33, an IL-1 family member, acts as an extracellular cytokine by binding its cognate receptor, ST2. IL-33 is also a chromatin-binding transcriptional regulator highly expressed in the nuclei of endothelial cells. However, the function of IL-33 as a nuclear factor is poorly defined. Here, we show that IL-33 is a novel transcriptional regulator of the p65 subunit of the NF-{kappa}B complex and is involved in endothelial cell activation. Quantitative reverse transcriptase PCR and Western blot analyses indicated that IL-33 mediates the expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 in endothelial cells basally and in response to tumor necrosis factor-{alpha}-treatment. IL-33-induced ICAM-1/VCAM-1 expression was dependent on the regulatory effect of IL-33 on the nuclear factor (NF)-{kappa}B pathway; NF-{kappa}B p65 expression was enhanced by IL-33 overexpression and, conversely, reduced by IL-33 knockdown. Moreover, NF-{kappa}B p65 promoter activity and chromatin immunoprecipitation analysis revealed that IL-33 binds to the p65 promoter region in the nucleus. Our data provide the first evidence that IL-33 in the nucleus of endothelial cells participates in inflammatory reactions as a transcriptional regulator of NF-{kappa}B p65.

  12. BFV activates the NF-κB pathway through its transactivator (BTas) to enhance viral transcription

    International Nuclear Information System (INIS)

    Wang Jian; Tan Juan; Zhang Xihui; Guo Hongyan; Zhang Qicheng; Guo Tingting; Geng Yunqi; Qiao Wentao

    2010-01-01

    Multiple families of viruses have evolved sophisticated strategies to regulate nuclear factor-κB (NF-κB) signaling, which plays a pivotal role in diverse cellular events, including virus-host interactions. In this study, we report that bovine foamy virus (BFV) is able to activate the NF-κB pathway through the action of its transactivator, BTas. Both cellular IKKβ and IκBα also participate in this activation. In addition, we demonstrate that BTas induces the processing of p100, which implies that BTas can activate NF-κB through a noncanonical pathway as well. Co-immunoprecipitation analysis shows that BTas interacts with IKK catalytic subunits (IKKα and IKKβ), which may be responsible for regulation of IKK kinase activity and persistent NF-κB activation. Furthermore, our results indicate that the level of BTas-mediated LTR transcription correlates with the activity of cellular NF-κB. Together, this study suggests that BFV activates the NF-κB pathway through BTas to enhance viral transcription.

  13. cAMP-response Element-binding Protein (CREB) and NF-κB Transcription Factors Are Activated during Prolonged Hypoxia and Cooperatively Regulate the Induction of Matrix Metalloproteinase MMP1*

    Science.gov (United States)

    Nakayama, Koh

    2013-01-01

    Responses to low levels of oxygen (hypoxia) are essential to maintain homeostasis. During the hypoxic response, gene expression is altered by various transcription factors. The transcription factor, hypoxia-inducible factor (HIF), plays a central role in the hypoxic response. The α subunit of HIF, which is actively degraded during normoxia, becomes stabilized during hypoxia, which leads to HIF activation. A microarray analysis of HeLa cells showed that expression of matrix metalloproteinase 1 (MMP1) was markedly induced during prolonged hypoxia. CREB and NF-κB binding sites were identified in the MMP1 promoter region between 1945 and 1896 nucleotides upstream of the transcription start site. Assays with luciferase reporters demonstrated that HIF activity was induced during the early phase of hypoxia, whereas CREB and NF-κB were activated during the later (prolonged) phase. Depletion of CREB and/or NF-κB reduced MMP1 induction during prolonged hypoxia both at the mRNA and protein levels. A chromatin immunoprecipitation assay demonstrated binding of CREB and NF-κB to the MMP1 promoter. Finally, cell migration and invasion on a collagen matrix and pulmonary metastasis in nude mice were inhibited after depletion of CREB and NF-κB in MDA-MB-231 cells. Taken together, these results suggest that the cooperative action of CREB and NF-κB plays an important role to induce MMP1 expression during prolonged hypoxia and regulates cell migration and invasion in cancer cells. PMID:23775082

  14. NF-Y loss triggers p53 stabilization and apoptosis in HPV18-positive cells by affecting E6 transcription

    OpenAIRE

    Benatti, Paolo; Basile, Valentina; Dolfini, Diletta; Belluti, Silvia; Tomei, Margherita; Imbriano, Carol

    2016-01-01

    The expression of the high risk HPV18 E6 and E7 oncogenic proteins induces the transformation of epithelial cells, through the disruption of p53 and Rb function. The binding of cellular transcription factors to cis-regulatory elements in the viral Upstream Regulatory Region (URR) stimulates E6/E7 transcription. Here, we demonstrate that the CCAAT-transcription factor NF-Y binds to a non-canonical motif within the URR and activates viral gene expression. In addition, NF-Y indirectly up-regulat...

  15. A critique on nuclear factor-kappa B and signal transducer and activator of transcription 3: The key transcription factors in periodontal pathogenesis

    Directory of Open Access Journals (Sweden)

    Ranjith Ambili

    2017-01-01

    Full Text Available Periodontal disease is initiated by microorganisms in dental plaque, and host immunoinflammatory response to the microbial challenge helps in disease progression. Conventional periodontal therapy was mainly targeted on the elimination of microbial component. However, a better understanding of molecular aspects in host response will enable the clinicians to formulate effective host modulation therapy (HMT for the periodontal management. Inflammatory mediators were the main targets for HMT in the past. Transcription factors can regulate the production of multiple mediators simultaneously, and inhibition of these factors will be more beneficial than blocking individual molecule. Two important transcription factors implicated in chronic inflammatory diseases are nuclear factor kappa B (NF-κB and signal transducers and activators of transcription 3. The role of these factors in periodontal disease is a less explored area. This comprehensive review is aimed at unveiling the critical role of NF-κB and signal transducers and activators of transcription 3 in periodontal pathogenesis. An online search was performed using MEDLINE/PubMed database. All publications till 2016 related to NF-κB, signal transducer and activator of transcription 3 (STAT3, and inflammation were included in writing this review. A total of 27,390 references were published based on the search terms used. Out of these, 507 were related to the periodontal research published in English till 2016. Relevant papers were chosen after carefully reading the abstract. This review has attempted to comprehend the existing knowledge regarding the role of transcription factors NF-κB and STAT3 in periodontal disease. Moreover, it also provides a connecting molecular link for the periodontal medicine concept.

  16. Foot-and-mouth disease virus leader proteinase inhibits dsRNA-induced type I interferon transcription by decreasing interferon regulatory factor 3/7 in protein levels

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dang; Fang, Liurong; Luo, Rui; Ye, Rui; Fang, Ying; Xie, Lilan; Chen, Huanchun [Division of Animal Infectious Diseases, State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070 (China); Xiao, Shaobo, E-mail: shaoboxiao@yahoo.com [Division of Animal Infectious Diseases, State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070 (China)

    2010-08-13

    Research highlights: {yields} FMDV L{sup pro} inhibits poly(I:C)-induced IFN-{alpha}1/{beta} mRNA expression. {yields} L{sup pro} inhibits MDA5-mediated activation of the IFN-{alpha}1/{beta} promoter. {yields} L{sup pro} significantly reduced the transcription of multiple IRF-responsive genes. {yields} L{sup pro} inhibits IFN-{alpha}1/{beta} promoter activation by decreasing IRF-3/7 in protein levels. {yields} The ability to process eIF-4G of L{sup pro} is not necessary to inhibit IFN-{alpha}1/{beta} activation. -- Abstract: The leader proteinase (L{sup pro}) of foot-and-mouth disease virus (FMDV) has been identified as an interferon-{beta} (IFN-{beta}) antagonist that disrupts the integrity of transcription factor nuclear factor {kappa}B (NF-{kappa}B). In this study, we showed that the reduction of double stranded RNA (dsRNA)-induced IFN-{alpha}1/{beta} expression caused by L{sup pro} was also associated with a decrease of interferon regulatory factor 3/7 (IRF-3/7) in protein levels, two critical transcription factors for activation of IFN-{alpha}/{beta}. Furthermore, overexpression of L{sup pro} significantly reduced the transcription of multiple IRF-responsive genes including 2',5'-OAS, ISG54, IP-10, and RANTES. Screening L{sup pro} mutants indicated that the ability to process eIF-4G of L{sup pro} is not required for suppressing dsRNA-induced activation of the IFN-{alpha}1/{beta} promoter and decreasing IRF-3/7 expression. Taken together, our results demonstrate that, in addition to disrupting NF-{kappa}B, L{sup pro} also decreases IRF-3/7 expression to suppress dsRNA-induced type I IFN production, suggesting multiple strategies used by FMDV to counteract the immune response to viral infection.

  17. Transcriptional profiles of Rel/NF-κB, inhibitor of NF-κB (IκB), and lipopolysaccharide-induced TNF-α factor (LITAF) in the lipopolysaccharide (LPS) and two Vibrio sp.-exposed intertidal copepod, Tigriopus japonicus.

    Science.gov (United States)

    Kim, Bo-Mi; Jeong, Chang-Bum; Rhee, Jae-Sung; Lee, Jae-Seong

    2014-02-01

    The immune system and the role of immunity-related genes have rarely been studied in copepods, even though copepods have a primitive immune response system and also have a potential in pathogen transport higher trophic levels. In this study, we firstly cloned and characterized three core immune genes such as nuclear factor κB (NF-κB), inhibitor of NF-κB (IκB), and lipopolysaccharide-induced TNF-α factor (LITAF) genes in the intertidal copepod Tigriopus japonicus. Several in silico analyses based on conserved domains, motifs, and phylogenetic relationships were supporting their annotations. To investigate the immune-related role of three genes, we exposed lipopolysaccharide (LPS) and two Vibrio sp. to T. japonicus. After exposure of different concentrations of LPS and two Vibrio sp., transcripts of TJ-IκB and TJ-LITAF genes were significantly elevated during the time course in a dose-dependent manner, while TJ-NF-κB transcripts were not significantly changed during exposure. These findings demonstrated that the copepod T. japonicus has a conserved immunity against infection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Scandoside Exerts Anti-Inflammatory Effect Via Suppressing NF-κB and MAPK Signaling Pathways in LPS-Induced RAW 264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Jingyu He

    2018-02-01

    Full Text Available The iridoids of Hedyotis diffusa Willd play an important role in the anti-inflammatory process, but the specific iridoid with anti-inflammatory effect and its mechanism has not be thoroughly studied. An iridoid compound named scandoside (SCA was isolated from H. diffusa and its anti-inflammatory effect was investigated in lipopolysaccharide (LPS-induced RAW 264.7 macrophages. Its anti-inflammatory mechanism was confirmed by in intro experiments and molecular docking analyses. As results, SCA significantly decreased the productions of nitric oxide (NO, prostaglandin E2 (PGE2, tumor necrosis factor-α (TNF-α and interleukin-6 (IL-6 and inhibited the levels of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (COX-2, TNF-α and IL-6 messenger RNA (mRNA expression in LPS-induced RAW 264.7 macrophages. SCA treatment suppressed the phosphorylation of inhibitor of nuclear transcription factor kappa-B alpaha (IκB-α, p38, extracellular signal-regulated kinase (ERK and c-Jun N-terminal kinase (JNK. The docking data suggested that SCA had great binding abilities to COX-2, iNOS and IκB. Taken together, the results indicated that the anti-inflammatory effect of SCA is due to inhibition of pro-inflammatory cytokines and mediators via suppressing the nuclear transcription factor kappa-B (NF-κB and mitogen-activated protein kinase (MAPK signaling pathways, which provided useful information for its application and development.

  19. Regulation of IFN regulatory factor 4 expression in human T cell leukemia virus-I-transformed T cells.

    Science.gov (United States)

    Sharma, Sonia; Grandvaux, Nathalie; Mamane, Yael; Genin, Pierre; Azimi, Nazli; Waldmann, Thomas; Hiscott, John

    2002-09-15

    IFN regulatory factor (IRF)-4 is a lymphoid/myeloid-restricted member of the IRF transcription factor family that plays an essential role in the homeostasis and function of mature lymphocytes. IRF-4 expression is tightly regulated in resting primary T cells and is transiently induced at the mRNA and protein levels after activation by Ag-mimetic stimuli such as TCR cross-linking or treatment with phorbol ester and calcium ionophore (PMA/ionomycin). However, IRF-4 is constitutively upregulated in human T cell leukemia virus type I (HTLV-I) infected T cells as a direct gene target for the HTLV-I Tax oncoprotein. In this study we demonstrate that chronic IRF-4 expression in HTLV-I-infected T lymphocytes is associated with a leukemic phenotype, and we examine the mechanisms by which continuous production of IRF-4 is achieved in HTLV-I-transformed T cells. IRF-4 expression in HTLV-1-infected cells is driven through activation of the NF-kappaB and NF-AT pathways, resulting in the binding of p50, p65, and c-Rel to the kappaB1 element and p50, c-Rel, and NF-ATp to the CD28RE element within the -617 to -209 region of the IRF-4 promoter. Furthermore, mutation of either the kappaB1 or CD28RE sites blocks Tax-mediated transactivation of the human IRF-4 promoter in T cells. These experiments constitute the first detailed analysis of human IRF-4 transcriptional regulation within the context of HTLV-I infection and transformation of CD4(+) T lymphocytes.

  20. Increased levels of NOTCH1, NF-kappaB, and other interconnected transcription factors characterize primitive sets of hematopoietic stem cells.

    Science.gov (United States)

    Panepucci, Rodrigo Alexandre; Oliveira, Lucila Habib B; Zanette, Dalila Luciola; Viu Carrara, Rita de Cassia; Araujo, Amélia Goes; Orellana, Maristela Delgado; Bonini de Palma, Patrícia Vianna; Menezes, Camila C B O; Covas, Dimas Tadeu; Zago, Marco Antonio

    2010-03-01

    As previously shown, higher levels of NOTCH1 and increased NF-kappaB signaling is a distinctive feature of the more primitive umbilical cord blood (UCB) CD34+ hematopoietic stem cells (HSCs), as compared to bone marrow (BM). Differences between BM and UCB cell composition also account for this finding. The CD133 marker defines a more primitive cell subset among CD34+ HSC with a proposed hemangioblast potential. To further evaluate the molecular basis related to the more primitive characteristics of UCB and CD133+ HSC, immunomagnetically purified human CD34+ and CD133+ cells from BM and UCB were used on gene expression microarrays studies. UCB CD34+ cells contained a significantly higher proportion of CD133+ cells than BM (70% and 40%, respectively). Cluster analysis showed that BM CD133+ cells grouped with the UCB cells (CD133+ and CD34+) rather than to BM CD34+ cells. Compared with CD34+ cells, CD133+ had a higher expression of many transcription factors (TFs). Promoter analysis on all these TF genes revealed a significantly higher frequency (than expected by chance) of NF-kappaB-binding sites (BS), including potentially novel NF-kappaB targets such as RUNX1, GATA3, and USF1. Selected transcripts of TF related to primitive hematopoiesis and self-renewal, such as RUNX1, GATA3, USF1, TAL1, HOXA9, HOXB4, NOTCH1, RELB, and NFKB2 were evaluated by real-time PCR and were all significantly positively correlated. Taken together, our data indicate the existence of an interconnected transcriptional network characterized by higher levels of NOTCH1, NF-kappaB, and other important TFs on more primitive HSC sets.

  1. Light induces translocation of NF-κB p65 to the mitochondria and suppresses expression of cytochrome c oxidase subunit III (COX III) in the rat retina

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, Hiroshi, E-mail: htomita@iwate-u.ac.jp [Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551 (Japan); Soft-Path Engineering Research Center (SPERC), Faculty of Science and Engineering, Iwate University, Morioka 020-8551 (Japan); Clinical Research, Innovation and Education Center, Tohoku University Hospital, 1-1 Seiryo, Aoba, Sendai, Miyagi 980-8574 (Japan); Tabata, Kitako, E-mail: ktabata@iwate-u.ac.jp [Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551 (Japan); Takahashi, Maki, E-mail: mqdelta@iwate-u.ac.jp [Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551 (Japan); Nishiyama, Fumiaki, E-mail: t2114018@iwate-u.ac.jp [Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551 (Japan); Sugano, Eriko, E-mail: sseriko@iwate-u.ac.jp [Laboratory of Visual Neuroscience, Graduate Course in Biological Sciences, Iwate University Division of Science and Engineering, 4-3-5 Ueda, Morioka, Iwate 020-8551 (Japan); Soft-Path Engineering Research Center (SPERC), Faculty of Science and Engineering, Iwate University, Morioka 020-8551 (Japan)

    2016-05-13

    The transcription factor nuclear factor kappaB (NF-κB) plays various roles in cell survival, apoptosis, and inflammation. In the rat retina, NF-κB activity increases after exposure to damaging light, resulting in degeneration of photoreceptors. Here, we report that in dark-adapted rats exposed for 6 h to bright white light, the p65 subunit of retinal NF-κB translocates to the mitochondria, an event associated with a decrease in expression of cytochrome c oxidase subunit III (COX III). However, sustained exposure for 12 h depleted p65 from the mitochondria, and enhanced COX III expression. Treatment with the protective antioxidant PBN prior to light exposure prevents p65 depletion in the mitochondria and COX III upregulation during prolonged exposure, and apoptosis in photoreceptor cells. These results indicate that COX III expression is sensitive to the abundance of NF-κB p65 in the mitochondria, which, in turn, is affected by exposure to damaging light. - Highlights: • Damaging light exposure of the retina induces NF-κB p65 mitochondrial translocation. • NF-κB p65 mitochondrial translocation is associated with the decrease of COX III expression. • Prolonged light exposure depletes mitochondrial p65 resulting in the increase in COX III expression. • NF-κB p65 and COX III expression play an important role in the light-induced photoreceptor degeneration.

  2. Light induces translocation of NF-κB p65 to the mitochondria and suppresses expression of cytochrome c oxidase subunit III (COX III) in the rat retina

    International Nuclear Information System (INIS)

    Tomita, Hiroshi; Tabata, Kitako; Takahashi, Maki; Nishiyama, Fumiaki; Sugano, Eriko

    2016-01-01

    The transcription factor nuclear factor kappaB (NF-κB) plays various roles in cell survival, apoptosis, and inflammation. In the rat retina, NF-κB activity increases after exposure to damaging light, resulting in degeneration of photoreceptors. Here, we report that in dark-adapted rats exposed for 6 h to bright white light, the p65 subunit of retinal NF-κB translocates to the mitochondria, an event associated with a decrease in expression of cytochrome c oxidase subunit III (COX III). However, sustained exposure for 12 h depleted p65 from the mitochondria, and enhanced COX III expression. Treatment with the protective antioxidant PBN prior to light exposure prevents p65 depletion in the mitochondria and COX III upregulation during prolonged exposure, and apoptosis in photoreceptor cells. These results indicate that COX III expression is sensitive to the abundance of NF-κB p65 in the mitochondria, which, in turn, is affected by exposure to damaging light. - Highlights: • Damaging light exposure of the retina induces NF-κB p65 mitochondrial translocation. • NF-κB p65 mitochondrial translocation is associated with the decrease of COX III expression. • Prolonged light exposure depletes mitochondrial p65 resulting in the increase in COX III expression. • NF-κB p65 and COX III expression play an important role in the light-induced photoreceptor degeneration.

  3. TRIM45 negatively regulates NF-κB-mediated transcription and suppresses cell proliferation

    International Nuclear Information System (INIS)

    Shibata, Mio; Sato, Tomonobu; Nukiwa, Ryota; Ariga, Tadashi; Hatakeyama, Shigetsugu

    2012-01-01

    Highlights: ► NF-κB plays an important role in cell survival and carcinogenesis. ► TRIM45 negatively regulates TNFα-induced NF-κB-mediated transcription. ► TRIM45 overexpression suppresses cell growth. ► TRIM45 acts as a repressor for the NF-κB signal and regulates cell growth. -- Abstract: The NF-κB signaling pathway plays an important role in cell survival, immunity, inflammation, carcinogenesis, and organogenesis. Activation of NF-κB is regulated by several posttranslational modifications including phosphorylation, neddylation and ubiquitination. The NF-κB signaling pathway is activated by two distinct signaling mechanisms and is strictly modulated by the ubiquitin–proteasome system. It has been reported that overexpression of TRIM45, one of the TRIM family ubiquitin ligases, suppresses transcriptional activities of Elk-1 and AP-1, which are targets of the MAPK signaling pathway. In this study, we showed that TRIM45 also negatively regulates TNFα-induced NF-κB-mediated transcription by a luciferase reporter assay and that TRIM45 lacking a RING domain also has an activity to inhibit the NF-κB signal. Moreover, we found that TRIM45 overexpression suppresses cell growth. These findings suggest that TRIM45 acts as a repressor for the NF-κB signal and regulates cell growth.

  4. Effects of protein-energy malnutrition on NF-kappaB signalling in murine peritoneal macrophages.

    Science.gov (United States)

    Fock, Ricardo Ambrósio; Rogero, Marcelo Macedo; Vinolo, Marco Aurélio Ramirez; Curi, Rui; Borges, Maria Carolina; Borelli, Primavera

    2010-04-01

    Protein-energy malnutrition (PEM) is an important public health problem affecting millions of people worldwide. PEM decreases resistance to infection, impairing a number of physiological processes. In unstimulated cells, NF-kappaB is kept from binding to its consensus sequence by the inhibitor I kappaB alpha, which retains NF-kappaB in the cytoplasm. Upon various signals, such as lipopolysaccharide (LPS), I kappaB alpha is rapidly degraded and NF-kappaB is induced to translocate into the nucleus, where it activates expression of various genes that participate in the inflammatory response, including those involved in the synthesis of TNF-alpha. TRAF-6 is a cytoplasmic adapter protein that links the stimulatory signal from Toll like receptor-4 to NF-kappaB. The aim of this study was to evaluate the effect of malnutrition on induction of TNF-alpha by LPS in murine peritoneal macrophages. We evaluated peritoneal cellularity, the expression of MyD88, TRAF-6, IKK, I kappaB alpha and NF-kappaB, NF-kappaB activation and TNF-alpha mRNA and protein synthesis in macrophages. Two-month-old male BALB/C mice were submitted to PEM with a low-protein diet that contained 2% protein, compared to 12% protein in the control diet. When the experimental group had lost about 20% of the original body weight, it was used in the subsequent experiments. Malnourished animals presented anemia, leucopenia and severe reduction in peritoneal cavity cellularity. TNF-alpha mRNA and protein levels of macrophages stimulated with LPS were significantly lower in malnourished animals. PEM also decreased TRAF-6 expression and NF-kappaB activation after LPS stimulation. These results led us to conclude that PEM changes NF-kB signalling pathway in macrophages to LPS stimulus.

  5. Common gene variants in the tumor necrosis factor (TNF and TNF receptor superfamilies and NF-kB transcription factors and non-Hodgkin lymphoma risk.

    Directory of Open Access Journals (Sweden)

    Sophia S Wang

    Full Text Available A promoter polymorphism in the pro-inflammatory cytokine tumor necrosis factor (TNF (TNF G-308A is associated with increased non-Hodgkin lymphoma (NHL risk. The protein product, TNF-alpha, activates the nuclear factor kappa beta (NF-kappaB transcription factor, and is critical for inflammatory and apoptotic responses in cancer progression. We hypothesized that the TNF and NF-kappaB pathways are important for NHL and that gene variations across the pathways may alter NHL risk.We genotyped 500 tag single nucleotide polymorphisms (SNPs from 48 candidate gene regions (defined as 20 kb 5', 10 kb 3' in the TNF and TNF receptor superfamilies and the NF-kappaB and related transcription factors, in 1946 NHL cases and 1808 controls pooled from three independent population-based case-control studies. We obtained a gene region-level summary of association by computing the minimum p-value ("minP test". We used logistic regression to compute odds ratios and 95% confidence intervals for NHL and four major NHL subtypes in relation to SNP genotypes and haplotypes. For NHL, the tail strength statistic supported an overall relationship between the TNF/NF-kappaB pathway and NHL (p = 0.02. We confirmed the association between TNF/LTA on chromosome 6p21.3 with NHL and found the LTA rs2844484 SNP most significantly and specifically associated with the major subtype, diffuse large B-cell lymphoma (DLBCL (p-trend = 0.001. We also implicated for the first time, variants in NFKBIL1 on chromosome 6p21.3, associated with NHL. Other gene regions identified as statistically significantly associated with NHL included FAS, IRF4, TNFSF13B, TANK, TNFSF7 and TNFRSF13C. Accordingly, the single most significant SNPs associated with NHL were FAS rs4934436 (p-trend = 0.0024, IRF4 rs12211228 (p-trend = 0.0026, TNFSF13B rs2582869 (p-trend = 0.0055, TANK rs1921310 (p-trend = 0.0025, TNFSF7 rs16994592 (p-trend = 0.0024, and TNFRSF13C rs6002551 (p-trend = 0.0074. All associations were

  6. Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

    International Nuclear Information System (INIS)

    Xiao, Xiao; Gang, Yi; Wang, Honghong; Wang, Jiayin; Zhao, Lina; Xu, Li; Liu, Zhiguo

    2015-01-01

    Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself. The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity

  7. Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xiao [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Gang, Yi [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi’an 710038, Shaanxi Province (China); Wang, Honghong [No. 518 Hospital of Chinese People’s Liberation Army, Xi’an 710043, Shaanxi Province (China); Wang, Jiayin [The Genome Institute, Washington University in St. Louis, St. Louis, MO 63108 (United States); Zhao, Lina [Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Xu, Li, E-mail: lxuhelen@163.com [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Liu, Zhiguo, E-mail: liuzhiguo@fmmu.edu.cn [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China)

    2015-02-06

    Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself. The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity.

  8. DNA Binding and Phosphorylation Regulate the Core Structure of the NF-κB p50 Transcription Factor.

    Science.gov (United States)

    Vonderach, Matthias; Byrne, Dominic P; Barran, Perdita E; Eyers, Patrick A; Eyers, Claire E

    2018-06-05

    The NF-κB transcription factors are known to be extensively phosphorylated, with dynamic site-specific modification regulating their ability to dimerize and interact with DNA. p50, the proteolytic product of p105 (NF-κB1), forms homodimers that bind DNA but lack intrinsic transactivation function, functioning as repressors of transcription from κB promoters. Here, we examine the roles of specific phosphorylation events catalysed by either protein kinase A (PKA c ) or Chk1, in regulating the functions of p50 homodimers. LC-MS/MS analysis of proteolysed p50 following in vitro phosphorylation allows us to define Ser328 and Ser337 as PKA c - and Chk1-mediated modifications, and pinpoint an additional four Chk1 phosphosites: Ser65, Thr152, Ser242 and Ser248. Native mass spectrometry (MS) reveals Chk1- and PKA c -regulated disruption of p50 homodimer formation through Ser337. Additionally, we characterise the Chk1-mediated phosphosite, Ser242, as a regulator of DNA binding, with a S242D p50 phosphomimetic exhibiting a > 10-fold reduction in DNA binding affinity. Conformational dynamics of phosphomimetic p50 variants, including S242D, are further explored using ion-mobility MS (IM-MS). Finally, comparative theoretical modelling with experimentally observed p50 conformers, in the absence and presence of DNA, reveals that the p50 homodimer undergoes conformational contraction during electrospray ionisation that is stabilised by complex formation with κB DNA. Graphical Abstract ᅟ.

  9. Hairpin-like fluorescent probe for imaging of NF-κB transcription factor activity.

    Science.gov (United States)

    Metelev, Valeri; Zhang, Surong; Tabatadze, David; Bogdanov, Alexei

    2011-04-20

    Three oligodeoxyribonucleotides (ODN) covalently labeled with near-infrared (NIR) fluorochromes were synthesized and characterized with a goal of comparing in vitro a hairpin-based and a duplex-based FRET probe designed for the detection of human recombinant NF-κB p50/p65 heterodimer binding to DNA. Using deoxyguanosine phosphoramidite with a phosphorus-linked aminoethylene (diethylene glycol) hydrophilic linker, we synthesized ODNs with internucleoside reactive sites. The hairpin loop amino linker was modified with IRDye 800CW (FRET acceptor), and the 3'-end was modified with Cy5.5 (FRET donor) using a dithio-linker. To obtain a duplex probe, we conjugated Cy5.5 and 800CW to complementary strands at the distance of ten base pairs in the resultant duplex. No quenching of dyes was observed in either probe. The FRET efficiency was higher in the duplex (71%) than in the hairpin (56%) due to a more favorable distance between the donor and the acceptor. However, the hairpin design allowed more precise ratiometric measurement of fluorescence intensity changes as a result of NF-κB p50/p65 binding to the probe. We determined that as a result of binding there was a statistically significant increase of fluorescence intensity of Cy5.5 (donor) due to a decrease of FRET if normalized by 800CW intensity measured independently of FRET. We conclude that the hairpin based probe design allows for the synthesis of a dual fluorescence imaging probe that renders signal changes that are simple to interpret and stoichiometrically correct for detecting transcription factor-DNA interactions.

  10. Identification of a novel A20-binding inhibitor of nuclear factor-kappa B activation termed ABIN-2.

    Science.gov (United States)

    Van Huffel, S; Delaei, F; Heyninck, K; De Valck, D; Beyaert, R

    2001-08-10

    The nuclear factor kappaB (NF-kappaB) plays a central role in the regulation of genes implicated in immune responses, inflammatory processes, and apoptotic cell death. The zinc finger protein A20 is a cellular inhibitor of NF-kappaB activation by various stimuli and plays a critical role in terminating NF-kappaB responses. The underlying mechanism for NF-kappaB inhibition by A20 is still unknown. A20 has been shown to interact with several proteins including tumor necrosis factor (TNF) receptor-associated factors 2 and 6, as well as the inhibitory protein of kappaB kinase (IKK) gamma protein. Here we report the cloning and characterization of ABIN-2, a previously unknown protein that binds to the COOH-terminal zinc finger domain of A20. NF-kappaB activation induced by TNF and interleukin-1 is inhibited by overexpression of ABIN-2. The latter also inhibits NF-kappaB activation induced by overexpression of receptor-interacting protein or TNF receptor-associated factor 2. In contrast, NF-kappaB activation by overexpression of IKKbeta or direct activators of the IKK complex, such as Tax, cannot be inhibited by ABIN-2. These results indicate that ABIN-2 interferes with NF-kappaB activation upstream of the IKK complex and that it might contribute to the NF-kappaB-inhibitory function of A20.

  11. NF-κB-dependent transcriptional upregulation of cyclin D1 exerts cytoprotection against hypoxic injury upon EGFR activation

    International Nuclear Information System (INIS)

    Chen, Zhi-Dong; Xu, Liang; Tang, Kan-Kai; Gong, Fang-Xiao; Liu, Jing-Quan; Ni, Yin; Jiang, Ling-Zhi; Hong, Jun; Han, Fang; Li, Qian; Yang, Xiang-Hong; Sun, Ren-Hua; Mo, Shi-Jing

    2016-01-01

    Apoptosis of neural cells is one of the main pathological features in hypoxic/ischemic brain injury. Nuclear factor-κB (NF-κB) might be a potential therapeutic target for hypoxic/ischemic brain injury since NF-κB has been found to be inactivated after hypoxia exposure, yet the underlying molecular mechanisms of NF-κB inactivation are largely unknown. Here we report that epidermal growth factor receptor (EGFR) activation prevents neuron-like PC12 cells apoptosis in response to hypoxia via restoring NF-κB-dependent transcriptional upregulation of cyclin D1. Functionally, EGFR activation by EGF stimulation mitigates hypoxia-induced PC12 cells apoptosis in both dose- and time-dependent manner. Of note, EGFR activation elevates IKKβ phosphorylation, increases IκBα ubiquitination, promotes P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as upregulates cyclin D1 expression. EGFR activation also abrogates the decrease of IKKβ phosphorylation, reduction of IκBα ubiquitination, blockade of P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as downregulation of cyclin D1 expression induced by hypoxia. Furthermore, NF-κB-dependent upregulation of cyclin D1 is instrumental for the EGFR-mediated cytoprotection against hypoxic apoptosis. In addition, the dephosphorylation of EGFR induced by either EGF siRNA transfection or anti-HB-EGF neutralization antibody treatment enhances hypoxic cytotoxicity, which are attenuated by EGF administration. Our results highlight the essential role of NF-κB-dependent transcriptional upregulation of cyclin D1 in EGFR-mediated cytoprotective effects under hypoxic preconditioning and support further investigation of EGF in clinical trials of patients with hypoxic/ischemic brain injury. - Highlights: • EGFR activation significantly decreases hypoxia-induced PC12 cells injury. • EGFR activation abrogates the transcriptional repression of cyclin D1 induced by hypoxia in a NF

  12. NF-κB-dependent transcriptional upregulation of cyclin D1 exerts cytoprotection against hypoxic injury upon EGFR activation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhi-Dong [Department of Critical Care Medicine, The First Affiliated Hospital of Huzhou Normal College, Huzhou 313000, Zhejiang (China); Xu, Liang [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Tang, Kan-Kai [Department of Critical Care Medicine, The First Affiliated Hospital of Huzhou Normal College, Huzhou 313000, Zhejiang (China); Gong, Fang-Xiao; Liu, Jing-Quan; Ni, Yin; Jiang, Ling-Zhi; Hong, Jun; Han, Fang; Li, Qian; Yang, Xiang-Hong [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Sun, Ren-Hua, E-mail: jqin168@hotmail.com [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Mo, Shi-Jing, E-mail: msj860307@163.com [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China)

    2016-09-10

    Apoptosis of neural cells is one of the main pathological features in hypoxic/ischemic brain injury. Nuclear factor-κB (NF-κB) might be a potential therapeutic target for hypoxic/ischemic brain injury since NF-κB has been found to be inactivated after hypoxia exposure, yet the underlying molecular mechanisms of NF-κB inactivation are largely unknown. Here we report that epidermal growth factor receptor (EGFR) activation prevents neuron-like PC12 cells apoptosis in response to hypoxia via restoring NF-κB-dependent transcriptional upregulation of cyclin D1. Functionally, EGFR activation by EGF stimulation mitigates hypoxia-induced PC12 cells apoptosis in both dose- and time-dependent manner. Of note, EGFR activation elevates IKKβ phosphorylation, increases IκBα ubiquitination, promotes P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as upregulates cyclin D1 expression. EGFR activation also abrogates the decrease of IKKβ phosphorylation, reduction of IκBα ubiquitination, blockade of P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as downregulation of cyclin D1 expression induced by hypoxia. Furthermore, NF-κB-dependent upregulation of cyclin D1 is instrumental for the EGFR-mediated cytoprotection against hypoxic apoptosis. In addition, the dephosphorylation of EGFR induced by either EGF siRNA transfection or anti-HB-EGF neutralization antibody treatment enhances hypoxic cytotoxicity, which are attenuated by EGF administration. Our results highlight the essential role of NF-κB-dependent transcriptional upregulation of cyclin D1 in EGFR-mediated cytoprotective effects under hypoxic preconditioning and support further investigation of EGF in clinical trials of patients with hypoxic/ischemic brain injury. - Highlights: • EGFR activation significantly decreases hypoxia-induced PC12 cells injury. • EGFR activation abrogates the transcriptional repression of cyclin D1 induced by hypoxia in a NF

  13. The PRR11-SKA2 Bidirectional Transcription Unit Is Negatively Regulated by p53 through NF-Y in Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Yitao Wang

    2017-03-01

    Full Text Available We previously identified proline-rich protein 11 (PRR11 as a novel cancer-related gene that is implicated in the regulation of cell cycle and tumorigenesis. Our recent study demonstrated that PRR11 and its adjacent gene, kinetochore associated 2 (SKA2, constitute a classic head-to-head gene pair that is coordinately regulated by nuclear factor Y (NF-Y. In the present study, we further show that the PRR11-SKA2 bidirectional transcription unit is an indirect target of the tumor suppressor p53. A luciferase reporter assay revealed that overexpression of wild type p53, but not mutant p53, significantly represses the basal activity and NF-Y mediated transactivation of the PRR11-SKA2 bidirectional promoter. Deletion and mutation analysis of the PRR11-SKA2 promoter revealed that p53-mediated PRR11-SKA2 repression is dependent on the presence of functional NF-Y binding sites. Furthermore, a co-immunoprecipitation assay revealed that p53 associates with NF-Y in lung cancer cells, and a chromatin immunoprecipitation assay showed that p53 represses PRR11-SKA2 transcription by reducing the binding amount of NF-Y in the PRR11-SKA2 promoter region. Consistently, the ability of p53 to downregulate PRR11-SKA2 transcription was significantly attenuated upon siRNA-mediated depletion of nuclear factor Y subunit beta (NF-YB. Notably, lung cancer patients with lower expression of either PRR11 or SKA2 along with wild type p53 exhibited the best overall survival compared with others with p53 mutation and/or higher expression of either PRR11 or SKA2. Taken together, our results demonstrate that p53 negatively regulates the expression of the PRR11-SKA2 bidirectional transcription unit through NF-Y, suggesting that the inability to repress the PRR11-SKA2 bidirectional transcription unit after loss of p53 might contribute to tumorigenesis.

  14. The divergence between the virus and cellular oxidative stress as separate environmental agents that trigger autoimmunity originates from their different procedural mechanisms of activating the same molecular entity: the transcription factor NF-kappa B

    Directory of Open Access Journals (Sweden)

    Norbert O. Temajo

    2017-07-01

    Full Text Available To happen, autoimmunity in man requires triggering by environmental factors: the viruses and cellular stress, in genetically primed individuals. The viruses and stress are operatives in this scene as stimuli for the activation of the transcription factor (TF, NF-ΚB. NF-ΚB is unusually activated: the viral activation occurs via serine residues-phosphorylation by IKKβ and IKKε, while the activation by oxidative stress occurs via tyrosine phosphorylation of IΚBα. The phosphorylation of particular amino acid residues of a given protein molecule modulates that protein’s polymorphic conformations, appropriately. For a TF, a given conformation influences its choice of cognate DNA sequence recognition as well as its interactions with neighboring molecules. The TF NF-ΚB performs a battery of regulatory functions. Because it is variously phosphorylated as seen above this implies that NF-ΚB is capable of assuming a multitude of polymorphic conformations that we refer to as “derivative isoforms”. Thus the virus activation of NF-ΚB occurring by phosphorylation at serines S536 and S468 is observed to generate the isoforms with the potential to activate the transcription of viral latency genes, hereby installing a latent infection. But oxidative stress activation of NF-ΚB occurs via phosphorylation of Tyr42 of IΚBα and this yields isoforms that activate the transcription of replication and transcription activator (RTA, the master lytic switch, which thereby abrogates the latency. The steps involved are that the stress-activated NF-ΚB and the viral miRNAs conjoin in a regulatory circuitry identified as feedback and feed-forward network motifs that co-accomplish the switching on of RTA which in turn activates the transcription of the immediate early genes BZLF1 and BRLF1. These two latter genes together mobilize the expression of the set of lytic genes, resulting in a lytic cascade and consequentially set in trend the viral journey to the

  15. Alterations in transcription factor binding in radioresistant human melanoma cells after ionizing radiation

    International Nuclear Information System (INIS)

    Sahijdak, W.M.; Yang, Chin-Rang; Zuckerman, J.S.; Meyers, M.; Boothman, D.A.

    1994-01-01

    We analyzed alterations in transcription factor binding to specific, known promoter DNA consensus sequences between irradiated and unirradiated radioresistant human melanoma (U1-Mel) cells. The goal of this study was to begin to investigate which transcription factors and DNA-binding sites are responsible for the induction of specific transcripts and proteins after ionizing radiation. Transcription factor binding was observed using DNA band-shift assays and oligonucleotide competition analyses. Confluence-arrested U1-Mel cells were irradiated (4.5 Gy) and harvested at 4 h. Double-stranded oligonucleotides containing known DNA-binding consensus sites for specific transcription factors were used. Increased DNA binding activity after ionizing radiation was noted with oligonucleotides containing the CREB, NF-kB and Sp1 consensus sites. No changes in protein binding to AP-1, AP-2, AP-3, or CTF/NF1, GRE or Oct-1 consensus sequences were noted. X-ray activation of select transcription factors, which bind certain consensus sites in promoters, may cause specific induction or repression of gene transcription. 22 refs., 2 figs

  16. The Regulation of NF-κB Subunits by Phosphorylation

    Directory of Open Access Journals (Sweden)

    Frank Christian

    2016-03-01

    Full Text Available The NF-κB transcription factor is the master regulator of the inflammatory response and is essential for the homeostasis of the immune system. NF-κB regulates the transcription of genes that control inflammation, immune cell development, cell cycle, proliferation, and cell death. The fundamental role that NF-κB plays in key physiological processes makes it an important factor in determining health and disease. The importance of NF-κB in tissue homeostasis and immunity has frustrated therapeutic approaches aimed at inhibiting NF-κB activation. However, significant research efforts have revealed the crucial contribution of NF-κB phosphorylation to controlling NF-κB directed transactivation. Importantly, NF-κB phosphorylation controls transcription in a gene-specific manner, offering new opportunities to selectively target NF-κB for therapeutic benefit. This review will focus on the phosphorylation of the NF-κB subunits and the impact on NF-κB function.

  17. Hepatitis C virus core protein regulates p300/CBP co-activation function. Possible role in the regulation of NF-AT1 transcriptional activity

    International Nuclear Information System (INIS)

    Gomez-Gonzalo, Marta; Benedicto, Ignacio; Carretero, Marta; Lara-Pezzi, Enrique; Maldonado-Rodriguez, Alejandra; Moreno-Otero, Ricardo; Lai, Michael M.C.; Lopez-Cabrera, Manuel

    2004-01-01

    Hepatitis C virus (HCV) core is a viral structural protein; it also participates in some cellular processes, including transcriptional regulation. However, the mechanisms of core-mediated transcriptional regulation remain poorly understood. Oncogenic virus proteins often target p300/CBP, a known co-activator of a wide variety of transcription factors, to regulate the expression of cellular and viral genes. Here we demonstrate, for the first time, that HCV core protein interacts with p300/CBP and enhances both its acetyl-transferase and transcriptional activities. In addition, we demonstrate that nuclear core protein activates the NH 2 -terminal transcription activation domain (TAD) of NF-AT1 in a p300/CBP-dependent manner. We propose a model in which core protein regulates the co-activation function of p300/CBP and activates NF-AT1, and probably other p300/CBP-regulated transcription factors, by a novel mechanism involving the regulation of the acetylation state of histones and/or components of the transcriptional machinery

  18. p38 mitogen-activated protein kinase up-regulates NF-κB transcriptional activation through RelA phosphorylation during stretch-induced myogenesis

    International Nuclear Information System (INIS)

    Ji, Guoping; Liu, Dongxu; Liu, Jing; Gao, Hui; Yuan, Xiao; Shen, Gang

    2010-01-01

    p38 MAPK and nuclear factor-B (NF-B) signaling pathways play an indispensable role in the control of skeletal myogenesis. The specific contribution of these signaling pathways to the response of myoblast to the mechanical stimulation and the molecular mechanisms underlying this response remain unresolved. Using an established in vitro model, we now show that p38 MAP kinase activity regulates the transcriptional activation of NF-κB in response to mechanical stimulation of myoblasts. Furthermore, SB203580 blocked stretch-induced NF-κB activation during myogenesis, not through down-regulation of degradation of IκB-α, and consequent translocation of the p65 subunit of NF-κB to the nucleus. It is likely that stretch-induced NF-κB activation by phosphorylation of p65 NF-κB. Moreover, depletion of p38α using siRNA significantly reduces stretch-induced phosphorylation of RelA and NF-κB activity. These results provides the first evidence of a cross-talk between p38 MAPK and NF-κB signaling pathways during stretch-induced myogenesis, with phosphorylation of RelA being one of the effectors of this promyogenic mechanism. The α isoform of p38MAP kinase regulates the transcriptional activation of NF-κB following stimulation with cyclic stretch.

  19. p38 mitogen-activated protein kinase up-regulates NF-{kappa}B transcriptional activation through RelA phosphorylation during stretch-induced myogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Guoping [Department of Orthodontics, College of Stomatology, Ninth People' s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Research Institute of Stomatology, Shanghai 200011 (China); Liu, Dongxu [Department of Orthodontics, College of Stomatology, Shandong University, Jinan, Shandong Province 250012 (China); Liu, Jing [Department of Orthodontics, The Affiliated Qingdao Municipal Hospital, Qingdao University, Qingdao, Shandong Province 266075 (China); Gao, Hui [Department of Orthodontics, Tianjin Stomatological Hospital, Tianjin 300041 (China); Yuan, Xiao, E-mail: yuanxiaoqd@163.com [Department of Orthodontics, The Affiliated Qingdao Municipal Hospital, Qingdao University, Qingdao, Shandong Province 266075 (China); Shen, Gang, E-mail: ganshen2007@163.com [Department of Orthodontics, College of Stomatology, Ninth People' s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Research Institute of Stomatology, Shanghai 200011 (China)

    2010-01-01

    p38 MAPK and nuclear factor-B (NF-B) signaling pathways play an indispensable role in the control of skeletal myogenesis. The specific contribution of these signaling pathways to the response of myoblast to the mechanical stimulation and the molecular mechanisms underlying this response remain unresolved. Using an established in vitro model, we now show that p38 MAP kinase activity regulates the transcriptional activation of NF-{kappa}B in response to mechanical stimulation of myoblasts. Furthermore, SB203580 blocked stretch-induced NF-{kappa}B activation during myogenesis, not through down-regulation of degradation of I{kappa}B-{alpha}, and consequent translocation of the p65 subunit of NF-{kappa}B to the nucleus. It is likely that stretch-induced NF-{kappa}B activation by phosphorylation of p65 NF-{kappa}B. Moreover, depletion of p38{alpha} using siRNA significantly reduces stretch-induced phosphorylation of RelA and NF-{kappa}B activity. These results provides the first evidence of a cross-talk between p38 MAPK and NF-{kappa}B signaling pathways during stretch-induced myogenesis, with phosphorylation of RelA being one of the effectors of this promyogenic mechanism. The {alpha} isoform of p38MAP kinase regulates the transcriptional activation of NF-{kappa}B following stimulation with cyclic stretch.

  20. Mitochondrial transcription factor A protects human retinal ...

    African Journals Online (AJOL)

    Purpose: To investigate the impact of mitochondrial transcription factor A (TFAM), as a modulator of NF-κB, on proliferation of hypoxia-induced human retinal endothelial cell (HREC), and the probable mechanism. Methods: After exposure to hypoxia (1 % O2) for 5 days, cell proliferation and cell cycle of HREC were ...

  1. Analysis and Quantitation of NF-[kappa]B Nuclear Translocation in Tumor Necrosis Factor Alpha (TNF-[alpha]) Activated Vascular Endothelial Cells

    Science.gov (United States)

    Fuseler, John W.; Merrill, Dana M.; Rogers, Jennifer A.; Grisham, Matthew B.; Wolf, Robert E.

    2006-07-01

    Nuclear factor kappa B (NF-[kappa]B) is a heterodimeric transcription factor typically composed of p50 and p65 subunits and is a pleiotropic regulator of various inflammatory and immune responses. In quiescent cells, p50/p65 dimers are sequestered in the cytoplasm bound to its inhibitors, the I-[kappa]Bs, which prevent entry into the nucleus. Following cellular stimulation, the I-[kappa]Bs are rapidly degraded, activating NF-[kappa]B. The active form of NF-[kappa]B rapidly translocates into the nucleus, binding to consensus sequences in the promoter/enhancer region of various genes, promoting their transcription. In human vascular endothelial cells activated with tumor necrosis factor-alpha, the activation and translocation of NF-[kappa]B is rapid, reaching maximal nuclear localization by 30 min. In this study, the appearance of NF-[kappa]B (p65 subunit, p65-NF-[kappa]B) in the nucleus visualized by immunofluorescence and quantified by morphometric image analysis (integrated optical density, IOD) is compared to the appearance of activated p65-NF-[kappa]B protein in the nucleus determined biochemically. The appearance of p65-NF-[kappa]B in the nucleus measured by fluorescence image analysis and biochemically express a linear correlation (R2 = 0.9477). These data suggest that localization and relative protein concentrations of NF-[kappa]B can be reliably determined from IOD measurements of the immunofluorescent labeled protein.

  2. Adrenergic regulation during acute hepatic infection with Entamoeba histolytica in the hamster: involvement of oxidative stress, Nrf2 and NF-KappaB

    Directory of Open Access Journals (Sweden)

    Aldaba-Muruato Liseth Rubi

    2017-01-01

    Full Text Available Oxidative stress and transcriptional pathways of nuclear factor erythroid 2-related factor 2 (Nrf2 and nuclear factor kappa-B (NF-κB are critically involved in the etiopathology of amebic liver abscess (ALA. In this work, we studied the relationship between the adrenergic nervous system and ALA in the hamster. ALA was visible at 12 h of infection. While 6-hydroxidopamine (6-OHDA decreased infection, propranolol (β-adrenergic blocker treatment was associated with less extensive liver damage, and phentolamine treatment (α-adrenergic blocker significantly reduced ALA compared to 6-OHDA and propranolol. Serum enzymatic activities of alanine aminotransferase (ALT and γ-glutamyl transpeptidase (γ-GTP were increased at 12 h post-infection. Chemical denervation and α and β-adrenergic blockers decreased ALT to normal levels, while 6-OHDA and propranolol showed a trend to decrease γ-GTP but phentolamine significantly reduced γ-GTP. Amebic infection increased oxidized glutathione (GSSG and decreased both reduced glutathione (GSH and the GSH/GSSG ratio. Propranolol and 6-OHDA showed a tendency to decrease GSSG. However, GSH, GSSG and GSH/GSSG returned to normal levels with phentolamine. Furthermore, amebic infection increased pNF-κB and interleukin-1β (IL-1β, and showed a tendency to decrease hemoxigenase-1 (HO-1, but not Nrf2. Chemical denervation showed a trend to decrease pNF-κB and IL-1β, and neither Nrf2 nor HO-1 increased significantly. In addition, NF-κB and IL-1β were attenuated by propranolol and phentolamine treatments, although phentolamine showed significant overexpression of Nrf2 and HO-1. This suggests that the adrenergic system may be involved in oxidative stress and in modulation of the Nrf2 and NF-κB pathways during ALA development.

  3. Influence of the dopaminergic system, CREB, and transcription factor-κB on cocaine neurotoxicity

    International Nuclear Information System (INIS)

    Planeta, C.S.; Lepsch, L.B.; Alves, R.; Scavone, C.

    2013-01-01

    Cocaine is a widely used drug and its abuse is associated with physical, psychiatric and social problems. Abnormalities in newborns have been demonstrated to be due to the toxic effects of cocaine during fetal development. The mechanism by which cocaine causes neurological damage is complex and involves interactions of the drug with several neurotransmitter systems, such as the increase of extracellular levels of dopamine and free radicals, and modulation of transcription factors. The aim of this review was to evaluate the importance of the dopaminergic system and the participation of inflammatory signaling in cocaine neurotoxicity. Our study showed that cocaine activates the transcription factors NF-κB and CREB, which regulate genes involved in cellular death. GBR 12909 (an inhibitor of dopamine reuptake), lidocaine (a local anesthetic), and dopamine did not activate NF-κB in the same way as cocaine. However, the attenuation of NF-κB activity after the pretreatment of the cells with SCH 23390, a D1 receptor antagonist, suggests that the activation of NF-κB by cocaine is, at least partially, due to activation of D1 receptors. NF-κB seems to have a protective role in these cells because its inhibition increased cellular death caused by cocaine. The increase in BDNF (brain-derived neurotrophic factor) mRNA can also be related to the protective role of both CREB and NF-κB transcription factors. An understanding of the mechanisms by which cocaine induces cell death in the brain will contribute to the development of new therapies for drug abusers, which can help to slow down the progress of degenerative processes

  4. Influence of the dopaminergic system, CREB, and transcription factor-κB on cocaine neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Planeta, C.S. [Laboratório de Neuropsicofarmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Lepsch, L.B.; Alves, R.; Scavone, C. [Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP (Brazil)

    2013-10-15

    Cocaine is a widely used drug and its abuse is associated with physical, psychiatric and social problems. Abnormalities in newborns have been demonstrated to be due to the toxic effects of cocaine during fetal development. The mechanism by which cocaine causes neurological damage is complex and involves interactions of the drug with several neurotransmitter systems, such as the increase of extracellular levels of dopamine and free radicals, and modulation of transcription factors. The aim of this review was to evaluate the importance of the dopaminergic system and the participation of inflammatory signaling in cocaine neurotoxicity. Our study showed that cocaine activates the transcription factors NF-κB and CREB, which regulate genes involved in cellular death. GBR 12909 (an inhibitor of dopamine reuptake), lidocaine (a local anesthetic), and dopamine did not activate NF-κB in the same way as cocaine. However, the attenuation of NF-κB activity after the pretreatment of the cells with SCH 23390, a D1 receptor antagonist, suggests that the activation of NF-κB by cocaine is, at least partially, due to activation of D1 receptors. NF-κB seems to have a protective role in these cells because its inhibition increased cellular death caused by cocaine. The increase in BDNF (brain-derived neurotrophic factor) mRNA can also be related to the protective role of both CREB and NF-κB transcription factors. An understanding of the mechanisms by which cocaine induces cell death in the brain will contribute to the development of new therapies for drug abusers, which can help to slow down the progress of degenerative processes.

  5. Plant nuclear factor Y (NF-Y) B subunits confer drought tolerance and lead to improved corn yields on water-limited acres.

    Science.gov (United States)

    Nelson, Donald E; Repetti, Peter P; Adams, Tom R; Creelman, Robert A; Wu, Jingrui; Warner, David C; Anstrom, Don C; Bensen, Robert J; Castiglioni, Paolo P; Donnarummo, Meghan G; Hinchey, Brendan S; Kumimoto, Roderick W; Maszle, Don R; Canales, Roger D; Krolikowski, Katherine A; Dotson, Stanton B; Gutterson, Neal; Ratcliffe, Oliver J; Heard, Jacqueline E

    2007-10-16

    Commercially improved crop performance under drought conditions has been challenging because of the complexity of the trait and the multitude of factors that influence yield. Here we report the results of a functional genomics approach that identified a transcription factor from the nuclear factor Y (NF-Y) family, AtNF-YB1, which acts through a previously undescribed mechanism to confer improved performance in Arabidopsis under drought conditions. An orthologous maize transcription factor, ZmNF-YB2, is shown to have an equivalent activity. Under water-limited conditions, transgenic maize plants with increased ZmNF-YB2 expression show tolerance to drought based on the responses of a number of stress-related parameters, including chlorophyll content, stomatal conductance, leaf temperature, reduced wilting, and maintenance of photosynthesis. These stress adaptations contribute to a grain yield advantage to maize under water-limited environments. The application of this technology has the potential to significantly impact maize production systems that experience drought.

  6. MtNF-YA1, a central transcriptional regulator of symbiotic nodule development, is also a determinant of Medicago truncatula susceptibility towards a root pathogen.

    Directory of Open Access Journals (Sweden)

    Thomas Rey

    2016-12-01

    Full Text Available Plant NF-Y transcription factors control a wide array of biological functions enabling appropriate reproductive and developmental processes as well as adaptation to various abiotic and biotic environments. In Medicago truncatula, MtNF-YA1 was previously identified as a key determinant for nodule development and establishment of rhizobial symbiosis. Here we highlight a new role for this protein in compatibility to Aphanomyces euteiches, a root pathogenic oomycete. The Mtnf-ya1-1 mutant plants showed better survival rate, reduced symptoms, and increased development of their root apparatus as compared to their wild type background A17. MtNF-YA-1 was specifically up-regulated by A. euteiches in F83005.5, a highly susceptible natural accession of M. truncatula while transcript level remained stable in A17, which is partially resistant. The role of MtNF-YA1 in F83005.5 susceptibility was further documented by reducing MtNF-YA1 expression either by overexpression of the miR169q, a microRNA targeting MtNF-YA1, or by RNAi approaches leading to a strong enhancement in the resistance of this susceptible line. Comparative analysis of the transcriptome of wild type and Mtnf-ya1-1 led to the identification of 1509 differentially expressed genes. Among those, almost 36 defence-related genes were constitutively expressed in Mtnf-ya1-1, while 20 genes linked to hormonal pathways were repressed. In summary, we revealed an unexpected dual role for this symbiotic transcription factor as a key player in the compatibility mechanisms to a pathogen.

  7. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    International Nuclear Information System (INIS)

    Sahu, Geetaram; Farley, Kalamo; El-Hage, Nazira; Aiamkitsumrit, Benjamas; Fassnacht, Ryan; Kashanchi, Fatah; Ochem, Alex; Simon, Gary L.; Karn, Jonathan; Hauser, Kurt F.; Tyagi, Mudit

    2015-01-01

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-ĸB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-ĸB at 276th serine residue. These modifications enhance the interaction of NF-ĸB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. - Highlights: • Cocaine induces the initiation phase of HIV transcription by activating NF-ĸB. • Cocaine induced NF-ĸB phosphorylation promotes its interaction with P300. • Cocaine enhances the elongation phase of HIV transcription by stimulating MSK1. • Cocaine activated MSK1 catalyzes the phosphorylation of histone H3 at its Ser10. • Cocaine induced H3S10 phosphorylation facilitates the recruitment of P-TEFb at LTR

  8. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Geetaram; Farley, Kalamo [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); El-Hage, Nazira [Virginia Commonwealth University, Richmond, VA (United States); Aiamkitsumrit, Benjamas; Fassnacht, Ryan [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Kashanchi, Fatah [George Mason University, Manassas, VA (United States); Ochem, Alex [ICGEB, Wernher and Beit Building, Anzio Road, Observatory, 7925 Cape Town (South Africa); Simon, Gary L. [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Karn, Jonathan [Case Western Reserve University, Cleveland, OH (United States); Hauser, Kurt F. [Virginia Commonwealth University, Richmond, VA (United States); Tyagi, Mudit, E-mail: tmudit@email.gwu.edu [Division of Infectious Diseases, Department of Medicine, George Washington University, Washington, DC (United States); Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC 20037 (United States)

    2015-09-15

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-ĸB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-ĸB at 276th serine residue. These modifications enhance the interaction of NF-ĸB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. - Highlights: • Cocaine induces the initiation phase of HIV transcription by activating NF-ĸB. • Cocaine induced NF-ĸB phosphorylation promotes its interaction with P300. • Cocaine enhances the elongation phase of HIV transcription by stimulating MSK1. • Cocaine activated MSK1 catalyzes the phosphorylation of histone H3 at its Ser10. • Cocaine induced H3S10 phosphorylation facilitates the recruitment of P-TEFb at LTR.

  9. Effects of acteoside on lipopolysaccharide-induced inflammation in acute lung injury via regulation of NF-κB pathway in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Jing, Wang; Chunhua, Ma, E-mail: machunhuabest@126.com; Shumin, Wang, E-mail: wangshuminch@126.com

    2015-06-01

    The purpose of the present study was to investigate the protective role of acteoside (AC) on lipopolysaccharide (LPS)-induced acute lung injury (ALI). BalB/c mice intraperitoneally received AC (30, and 60 mg/kg) or dexamethasone (2 mg/kg) 2 h prior to or after intratracheal instillation of LPS. Treatment with AC significantly decreased lung wet-to-dry weight (W/D) ratio and lung myeloperoxidase (MPO) activity and ameliorated LPS-induced lung histopathological changes. In addition, AC increased super oxide dismutase (SOD) level and inhibited malondialdehyde (MDA) content, total cell and neutrophil infiltrations, and levels of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF) in LPS-stimulated mice. Furthermore, we demonstrated that AC inhibited the phosphorylation of IκBα, nuclear factor-κB (NF-κB) p65, inhibitor of nuclear factor kappa-B kinase-α (IKK-α) and inhibitor of nuclear factor kappa-B kinase-β (IKKβ) in LPS-induced inflammation in A549 cells. Our data suggested that LPS evoked the inflammatory response in lung epithelial cells A549. The experimental results indicated that the protective mechanism of AC might be attributed partly to the inhibition of proinflammatory cytokine production and NF-κB activation. - Highlights: • Acteoside inhibited inflammation in LPS-induced lung injury in mice. • Acteoside inhibited inflammation in lung epithelial cells A549. • Acteoside inhibited NF-kB activation in LPS-induced mice and lung epithelial cells A549.

  10. Analyzing the soybean transcriptome during autoregulation of mycorrhization identifies the transcription factors GmNF-YA1a/b as positive regulators of arbuscular mycorrhization.

    Science.gov (United States)

    Schaarschmidt, Sara; Gresshoff, Peter M; Hause, Bettina

    2013-06-18

    Similarly to the legume-rhizobia symbiosis, the arbuscular mycorrhiza interaction is controlled by autoregulation representing a feedback inhibition involving the CLAVATA1-like receptor kinase NARK in shoots. However, little is known about signals and targets down-stream of NARK. To find NARK-related transcriptional changes in mycorrhizal soybean (Glycine max) plants, we analyzed wild-type and two nark mutant lines interacting with the arbuscular mycorrhiza fungus Rhizophagus irregularis. Affymetrix GeneChip analysis of non-inoculated and partially inoculated plants in a split-root system identified genes with potential regulation by arbuscular mycorrhiza or NARK. Most transcriptional changes occur locally during arbuscular mycorrhiza symbiosis and independently of NARK. RT-qPCR analysis verified nine genes as NARK-dependently regulated. Most of them have lower expression in roots or shoots of wild type compared to nark mutants, including genes encoding the receptor kinase GmSIK1, proteins with putative function as ornithine acetyl transferase, and a DEAD box RNA helicase. A predicted annexin named GmAnnx1a is differentially regulated by NARK and arbuscular mycorrhiza in distinct plant organs. Two putative CCAAT-binding transcription factor genes named GmNF-YA1a and GmNF-YA1b are down-regulated NARK-dependently in non-infected roots of mycorrhizal wild-type plants and functional gene analysis confirmed a positive role for these genes in the development of an arbuscular mycorrhiza symbiosis. Our results indicate GmNF-YA1a/b as positive regulators in arbuscular mycorrhiza establishment, whose expression is down-regulated by NARK in the autoregulated root tissue thereby diminishing subsequent infections. Genes regulated independently of arbuscular mycorrhization by NARK support an additional function of NARK in symbioses-independent mechanisms.

  11. Polyphenol Compound as a Transcription Factor Inhibitor.

    Science.gov (United States)

    Park, Seyeon

    2015-10-30

    A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor-DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein-protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1), c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and β-catenin/T cell factor (Tcf)).

  12. Transcriptional Activity of Nuclear Factor κB Family Genes in Patients with Systemic Sclerosis.

    Science.gov (United States)

    Lis-Święty, Anna; Gola, Joanna; Mazurek, Urszula; Brzezińska-Wcisło, Ligia

    2017-05-01

    Systemic sclerosis (SSc) is a connective tissue disease of unknown etiology and unclear pathogenesis. Evaluation of the activation of nuclear factor κB (NF-κB) family genes IκBα, p50, p52, p65, and c-Rel, potentially involved in the regulation of immunity, inflammation, angiogenesis, and tissue remodeling in SSc, was carried out. The study included 19 patients with limited SSc, 11 patients with early SSc, and 10 healthy persons constituting the control group. Real-time QRT-PCR was used to evaluate the mRNAs in peripheral blood samples. The patients with early SSc showed a decrease in transcriptional activity of IκBα inhibitor and c-Rel subunit. Transcriptional activity decrease in the other patients with limited SSc included genes encoding c-Rel and p50, subunits of NF-κB factor. Deregulation of intracellular signal transduction by NF-κB takes place at the beginning of SSc and in its fibrosis stage. Associations between clinical variables and NF-κB related gene expression as well as the activation of NF-κB family members in SSc patients should be addressed in future studies. © 2017 by the Association of Clinical Scientists, Inc.

  13. Polyphenol Compound as a Transcription Factor Inhibitor

    Directory of Open Access Journals (Sweden)

    Seyeon Park

    2015-10-01

    Full Text Available A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor–DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein–protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1, c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and β-catenin/T cell factor (Tcf.

  14. NF-kappaB: Two Sides of the Same Coin.

    Science.gov (United States)

    Pires, Bruno R B; Silva, Rafael C M C; Ferreira, Gerson M; Abdelhay, Eliana

    2018-01-09

    Nuclear Factor-kappa B (NF-κB) is a transcription factor family that regulates a large number of genes that are involved in important physiological processes, including survival, inflammation, and immune responses. More recently, constitutive expression of NF-κB has been associated with several types of cancer. In addition, microorganisms, such as viruses and bacteria, cooperate in the activation of NF-κB in tumors, confirming the multifactorial role of this transcription factor as a cancer driver. Recent reports have shown that the NF-κB signaling pathway should receive attention for the development of therapies. In addition to the direct effects of NF-κB in cancer cells, it might also impact immune cells that can both promote or prevent tumor development. Currently, with the rise of cancer immunotherapy, the link among immune cells, inflammation, and cancer is a major focus, and NF-κB could be an important regulator for the success of these therapies. This review discusses the contrasting roles of NF-κB as a regulator of pro- and antitumor processes and its potential as a therapeutic target.

  15. NF-κB Directly Regulates Fas Transcription to Modulate Fas-mediated Apoptosis and Tumor Suppression*

    Science.gov (United States)

    Liu, Feiyan; Bardhan, Kankana; Yang, Dafeng; Thangaraju, Muthusamy; Ganapathy, Vadivel; Waller, Jennifer L.; Liles, Georgia B.; Lee, Jeffrey R.; Liu, Kebin

    2012-01-01

    Fas is a member of the death receptor family. Stimulation of Fas leads to induction of apoptotic signals, such as caspase 8 activation, as well as “non-apoptotic” cellular responses, notably NF-κB activation. Convincing experimental data have identified NF-κB as a critical promoter of cancer development, creating a solid rationale for the development of antitumor therapy that suppresses NF-κB activity. On the other hand, compelling data have also shown that NF-κB activity enhances tumor cell sensitivity to apoptosis and senescence. Furthermore, although stimulation of Fas activates NF-κB, the function of NF-κB in the Fas-mediated apoptosis pathway remains largely undefined. In this study, we observed that deficiency of either Fas or FasL resulted in significantly increased incidence of 3-methylcholanthrene-induced spontaneous sarcoma development in mice. Furthermore, Fas-deficient mice also exhibited significantly greater incidence of azoxymethane and dextran sodium sulfate-induced colon carcinoma. In addition, human colorectal cancer patients with high Fas protein in their tumor cells had a longer time before recurrence occurred. Engagement of Fas with FasL triggered NF-κB activation. Interestingly, canonical NF-κB was found to directly bind to the FAS promoter. Blocking canonical NF-κB activation diminished Fas expression, whereas blocking alternate NF-κB increased Fas expression in human carcinoma cells. Moreover, although canonical NF-κB protected mouse embryo fibroblast (MEF) cells from TNFα-induced apoptosis, knocking out p65 diminished Fas expression in MEF cells, resulting in inhibition of FasL-induced caspase 8 activation and apoptosis. In contrast, knocking out p52 increased Fas expression in MEF cells. Our observations suggest that canonical NF-κB is a Fas transcription activator and alternate NF-κB is a Fas transcription repressor, and Fas functions as a suppressor of spontaneous sarcoma and colon carcinoma. PMID:22669972

  16. Sp1/3 and NF-1 mediate basal transcription of the human P2X1 gene in megakaryoblastic MEG-01 cells

    Directory of Open Access Journals (Sweden)

    Ennion Steven J

    2006-03-01

    shown that binding of Sp1/3 and NF-1 to elements in the direct vicinity of the transcription start site is essential for basal transcription. Targeting the function of these transcription factors in megakaryocytes may therefore provide a basis for the future therapeutic manipulation of platelet P2X1 function.

  17. NF1, Sp1 and HSF1 are synergistically involved in sulfide-induced sqr activation in echiuran worm Urechis unicinctus

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaolong; Qin, Zhenkui; Li, Xueyu; Ma, Xiaoyu; Gao, Beibei; Zhang, Zhifeng, E-mail: zzfp107@ouc.edu.cn

    2016-06-15

    Highlights: • Sulfide activates sqr transcription against respiratory toxicity in Urechis unicinctus. • Sulfide increases expressions and activities of NF1, Sp1 and HSF1 in a time-dependent manner. • NF1 and Sp1 participate in both basal and early sulfide-induced sqr transcription. • HSF1 functions more significantly than NF1 and Sp1 in sulfide-induced sqr transcription. • Transcription factors NF1, Sp1 and HSF1 enhance sqr promoter activity synergistically. - Abstract: Background: Sulfide is a well-known environmental toxic substance. Mitochondrial sulfide oxidation is a main mechanism of sulfide detoxification in organisms, and sulfide: quinone oxidoreductase (SQR) is a key enzyme which is involved in transferring electrons from sulfide to ubiquinone and converting sulfide into thiosulfate. Previous studies have revealed the SQR-mediated mitochondrial sulfide oxidation exists in the echiuran worm Urechis unicinctus, and its sqr mRNA level increased significantly when the worm is exposed to sulfide. In this study, we attempt to reveal the synergistic regulation of transcription factors on sulfide-induced sqr transcription in U. unicinctus. Methods: ChIP and EMSA were used to identify the interactions between sqr proximal promoter (from −391 to +194 bp) and transcription factors NF1 (nuclear factor 1) and Sp1 (specificity protein 1). Site-directed mutation and transfection assays further revealed their binding sites and synergistic roles of HSF1, NF1 and Sp1 in the sqr transcription. When U. unicinctus were exposed to 150 μM sulfide, the expression levels and nuclear contents of NF1 and Sp1 were examined by Western blotting, and the binding contents between NF1 or Sp1 and the sqr promoter were also detected by ChIP. Results: Transcription factors NF1 and Sp1 were confirmed to interact with the sqr proximal promoter, and their binding sites were identified in −75 to −69 bp for NF1 and −210 to −201 bp for Sp1. Transfection assays showed mutation

  18. Ganoderma lucidum ethanol extract inhibits the inflammatory response by suppressing the NF-κB and toll-like receptor pathways in lipopolysaccharide-stimulated BV2 microglial cells.

    Science.gov (United States)

    Yoon, Hyun-Min; Jang, Kyung-Jun; Han, Min Seok; Jeong, Jin-Woo; Kim, Gi Young; Lee, Jai-Heon; Choi, Yung Hyun

    2013-03-01

    Ganoderma lucidum is a traditional Oriental medicine that has been widely used as a tonic to promote longevity and health in Korea and other Asian countries. Although a great deal of work has been carried out on the therapeutic potential of this mushroom, the pharmacological mechanisms of its anti-inflammatory actions remain unclear. In this study, we evaluated the inhibitory effects of G. lucidum ethanol extract (EGL) on the production of inflammatory mediators and cytokines in lipopolysaccharide (LPS)-stimulated murine BV2 microglia. We also investigated the effects of EGL on the LPS-induced activation of nuclear factor kappaB (NF-κB) and upregulation of toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88). Elevated levels of nitric oxide (NO), prostaglandin E(2) (PGE(2)) and pro-inflammatory cytokine production were detected in BV2 microglia following LPS stimulation. We identifed that EGL significantly inhibits the excessive production of NO, PGE(2) and pro-inflammatory cytokines, including interleukin (IL)-1β and tumor necrosis factor-α in a concentration-dependent manner without causing cytotoxicity. In addition, EGL suppressed NF-κB translocation and transcriptional activity by blocking IκB degradation and inhibiting TLR4 and MyD88 expression in LPS-stimulated BV2 cells. Our results indicate that the inhibitory effects of EGL on LPS-stimulated inflammatory responses in BV2 microglia are associated with the suppression of the NF-κB and TLR signaling pathways. Therefore, EGL may be useful in the treatment of neurodegenerative diseases by inhibiting inflammatory mediator responses in activated microglia.

  19. Transcriptional regulators of legume-rhizobia symbiosis: nuclear factors Ys and GRAS are two for tango.

    Science.gov (United States)

    Rípodas, Carolina; Clúa, Joaquín; Battaglia, Marina; Baudin, Maël; Niebel, Andreas; Zanetti, María Eugenia; Blanco, Flavio

    2014-01-01

    Transcription factors are DNA binding proteins that regulate gene expression. The nitrogen fixing symbiosis established between legume plants and soil bacteria is a complex interaction, in which plants need to integrate signals derived from the symbiont and the surrounding environment to initiate the developmental program of nodule organogenesis and the infection process. Several transcription factors that play critical roles in these processes have been reported in the past decade, including proteins of the GRAS and NF-Y families. Recently, we reported the characterization of a new GRAS domain containing-protein that interacts with a member of the C subunit of the NF-Y family, which plays an important role in nodule development and the progression of bacterial infection during the symbiotic interaction. The connection between transcription factors of these families highlights the significance of multimeric complexes in the fabulous capacity of plants to integrate and respond to multiple environmental stimuli.

  20. Inhibition of transcription factor NF-kappaB signaling proteins IKKbeta and p65 through specific cysteine residues by epoxyquinone A monomer: correlation with its anti-cancer cell growth activity.

    Science.gov (United States)

    Liang, Mei-Chih; Bardhan, Sujata; Pace, Emily A; Rosman, Diana; Beutler, John A; Porco, John A; Gilmore, Thomas D

    2006-02-28

    Transcription factor NF-kappaB is constitutively active in many human chronic inflammatory diseases and cancers. Epoxyquinone A monomer (EqM), a synthetic derivative of the natural product epoxyquinol A, has previously been shown to be a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha)-induced activation of NF-kappaB, but the mechanism by which EqM inhibits NF-kappaB activation was not known. In this report, we show that EqM blocks activation of NF-kappaB by inhibiting two molecular targets: IkappaB kinase IKKbeta and NF-kappaB subunit p65. EqM inhibits TNF-alpha-induced IkappaBalpha phosphorylation and degradation by targeting IKKbeta, and an alanine substitution for Cys179 in the activation loop of IKKbeta makes it resistant to EqM-mediated inhibition. EqM also directly inhibits DNA binding by p65, but not p50; moreover, replacement of Cys38 in p65 with Ser abolishes EqM-mediated inhibition of DNA binding. Pretreatment of cells with reducing agent dithiothreitol dose-dependently reduces EqM-mediated inhibition of NF-kappaB, further suggesting that EqM directly modifies the thiol group of Cys residues in protein targets. Modifications of the exocyclic alkene of EqM substantially reduce EqM's ability to inhibit NF-kappaB activation. In the human SUDHL-4 lymphoma cell line, EqM inhibits both proliferation and NF-kappaB DNA binding, and activates caspase-3 activity. EqM also effectively inhibits the growth of human leukemia, kidney, and colon cancer cell lines in the NCI's tumor cell panel. Among six colon cancer cell lines, those with low amounts of constitutive NF-kappaB DNA-binding activity are generally more sensitive to growth inhibition by EqM. Taken together, these results suggest that EqM inhibits growth and induces cell death in tumor cells through a mechanism that involves inhibition of NF-kappaB activity at multiple steps in the signaling pathway.

  1. Heterochromatin protein 1 gamma and IκB kinase alpha interdependence during tumour necrosis factor gene transcription elongation in activated macrophages.

    Science.gov (United States)

    Thorne, James L; Ouboussad, Lylia; Lefevre, Pascal F

    2012-09-01

    IκB kinase α (IKKα) is part of the cytoplasmic IKK complex regulating nuclear factor-κB (NF-κB) release and translocation into the nucleus in response to pro-inflammatory signals. IKKα can also be recruited directly to the promoter of NF-κB-dependent genes by NF-κB where it phosphorylates histone H3 at serine 10, triggering recruitment of the bromodomain-containing protein 4 and the positive transcription elongation factor b. Herein, we report that IKKα travels with the elongating form of ribonucleic acid polymerase II together with heterochromatin protein 1 gamma (HP1γ) at NF-κB-dependent genes in activated macrophages. IKKα binds to and phosphorylates HP1γ, which in turn controls IKKα binding to chromatin and phosphorylation of the histone variant H3.3 at serine 31 within transcribing regions. Downstream of transcription end sites, IKKα accumulates with its inhibitor the CUE-domain containing protein 2, suggesting a link between IKKα inactivation and transcription termination.

  2. Involvement of nuclear factor {kappa}B in platelet CD40 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Hachem, Ahmed [Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, Quebec, Canada H1T 1C8 (Canada); Yacoub, Daniel [Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, Quebec, Canada H1T 1C8 (Canada); Centre Hospitalier Universite de Montreal, 264 boul. Rene-Levesque est, Montreal, Quebec, Canada H2X 1P1 (Canada); Zaid, Younes [Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, Quebec, Canada H1T 1C8 (Canada); Mourad, Walid [Universite de Montreal, Department of Medicine, 2900 boul. Edouard-Montpetit, Montreal, Quebec, Canada H3T 1J4 (Canada); Centre Hospitalier Universite de Montreal, 264 boul. Rene-Levesque est, Montreal, Quebec, Canada H2X 1P1 (Canada); Merhi, Yahye, E-mail: yahye.merhi@icm-mhi.org [Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, 5000 Belanger, Montreal, Quebec, Canada H1T 1C8 (Canada); Universite de Montreal, Department of Medicine, 2900 boul. Edouard-Montpetit, Montreal, Quebec, Canada H3T 1J4 (Canada)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer sCD40L induces TRAF2 association to CD40 and NF-{kappa}B activation in platelets. Black-Right-Pointing-Pointer I{kappa}B{alpha} phosphorylation downstream of CD40L/CD40 signaling is independent of p38 MAPK phosphorylation. Black-Right-Pointing-Pointer I{kappa}B{alpha} is required for sCD40L-induced platelet activation and potentiation of aggregation. -- Abstract: CD40 ligand (CD40L) is a thrombo-inflammatory molecule that predicts cardiovascular events. Platelets constitute the major source of soluble CD40L (sCD40L), which has been shown to potentiate platelet activation and aggregation, in a CD40-dependent manner, via p38 mitogen activated protein kinase (MAPK) and Rac1 signaling. In many cells, the CD40L/CD40 dyad also induces activation of nuclear factor kappa B (NF-{kappa}B). Given that platelets contain NF-{kappa}B, we hypothesized that it may be involved in platelet CD40 signaling and function. In human platelets, sCD40L induces association of CD40 with its adaptor protein the tumor necrosis factor receptor associated factor 2 and triggers phosphorylation of I{kappa}B{alpha}, which are abolished by CD40L blockade. Inhibition of I{kappa}B{alpha} phosphorylation reverses sCD40L-induced I{kappa}B{alpha} phosphorylation without affecting p38 MAPK phosphorylation. On the other hand, inhibition of p38 MAPK phosphorylation has no effect on I{kappa}B{alpha} phosphorylation, indicating a divergence in the signaling pathway originating from CD40 upon its ligation. In functional studies, inhibition of I{kappa}B{alpha} phosphorylation reverses sCD40L-induced platelet activation and potentiation of platelet aggregation in response to a sub-threshold concentration of collagen. This study demonstrates that the sCD40L/CD40 axis triggers NF-{kappa}B activation in platelets. This signaling pathway plays a critical role in platelet activation and aggregation upon sCD40L stimulation and may represent an important target against thrombo

  3. Thrombin-induced, TNFR-dependent miR-181c downregulation promotes MLL1 and NF-κB target gene expression in human microglia.

    Science.gov (United States)

    Yin, Min; Chen, Zhiying; Ouyang, Yetong; Zhang, Huiyan; Wan, Zhigang; Wang, Han; Wu, Wei; Yin, Xiaoping

    2017-06-29

    Controlling thrombin-driven microglial activation may serve as a therapeutic target for intracerebral hemorrhage (ICH). Here, we investigated microRNA (miRNA)-based regulation of thrombin-driven microglial activation using an in vitro thrombin toxicity model applied to primary human microglia. A miRNA array identified 22 differential miRNA candidates. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) identified miR-181c as the most significantly downregulated miRNA. TargetScan analysis identified mixed lineage leukemia-1 (MLL1) as a putative gene target for miR-181c. qRT-PCR was applied to assess tumor necrosis factor-alpha (TNF-α), miR-181c, and MLL1 levels following thrombin or proteinase-activated receptor-4-specific activating peptide (PAR4AP) exposure. Anti-TNF-α antibodies and tumor necrosis factor receptor (TNFR) silencing were employed to test TNF-α/TNFR dependence. A dual-luciferase reporter system and miR-181c mimic transfection assessed whether mir-181c directly binds to and negatively regulates MLL1. Nuclear factor kappa-B (NF-κB)-dependent luciferase reporter assays and NF-κB target gene expression were assessed in wild-type (MLL1+) and MLL1-silenced cells. Thrombin or PAR4AP-induced miR-181c downregulation (p < 0.05) and MLL1 upregulation (p < 0.05) that were dependent upon TNF-α/TNFR. miR-181c decreased wild-type MLL1 3'-UTR luciferase reporter activity (p < 0.05), and a miR-181c mimic suppressed MLL1 expression (p < 0.05). Thrombin treatment increased, while miR-181c reduced, NF-κB activity and NF-κB target gene expression in both wild-type (MLL1+) and MLL1-silenced cells (p < 0.05). Thrombin-induced, TNF-α/TNFR-dependent miR-181c downregulation promotes MLL1 expression, increases NF-κB activity, and upregulates NF-κB target gene expression. As miR-181c opposes thrombin's stimulation of pro-inflammatory NF-κB activity, miR-181c mimic therapy may show promise in controlling thrombin

  4. KLF2 in Regulation of NF-κB-Mediated Immune Cell Function and Inflammation

    Directory of Open Access Journals (Sweden)

    Prerana Jha

    2017-11-01

    Full Text Available KLF2 (Kruppel-like factor 2 is a member of the zinc finger transcription factor family, which critically regulates embryonic lung development, function of endothelial cells and maintenance of quiescence in T-cells and monocytes. It is expressed in naïve T-cells and monocytes, however its level of expression decreases during activation and differentiation. KLF2 also plays critical regulatory role in various inflammatory diseases and their pathogenesis. Nuclear factor-kappaB (NF-κB is an important inducer of inflammation and the inflammation is mediated through the transcription of several proinflammatory cytokines, chemokines and adhesion molecules. So, both transcriptional factors KLF2 and NF-κB are being associated with the similar cellular functions and their maintenance. It was shown that KLF2 regulates most of the NF-κB-mediated activities. In this review, we focused on emphasizing the involvement of KLF2 in health and disease states and how they interact with transcriptional master regulator NF-κB.

  5. Cocaine promotes both initiation and elongation phase of HIV-1 transcription by activating NF-κB and MSK1 and inducing selective epigenetic modifications at HIV-1 LTR

    Science.gov (United States)

    Sahu, Geetaram; Farley, Kalamo; El-Hage, Nazira; Aiamkitsumrit, Benjamas; Fassnacht, Ryan; Kashanchi, Fatah; Ochem, Alex; Simon, Gary L.; Karn, Jonathan; Hauser, Kurt F.; Tyagi, Mudit

    2015-01-01

    Cocaine accelerates human immunodeficiency virus (HIV-1) replication by altering specific cell-signaling and epigenetic pathways. We have elucidated the underlying molecular mechanisms through which cocaine exerts its effect in myeloid cells, a major target of HIV-1 in central nervous system (CNS). We demonstrate that cocaine treatment promotes HIV-1 gene expression by activating both nuclear factor-kappa B (NF-κB) and mitogen- and stress-activated kinase 1 (MSK1). MSK1 subsequently catalyzes the phosphorylation of histone H3 at serine 10, and p65 subunit of NF-κB at 276th serine residue. These modifications enhance the interaction of NF-κB with P300 and promote the recruitment of the positive transcription elongation factor b (P-TEFb) to the HIV-1 LTR, supporting the development of an open/relaxed chromatin configuration, and facilitating the initiation and elongation phases of HIV-1 transcription. Results are also confirmed in primary monocyte derived macrophages (MDM). Overall, our study provides detailed insights into cocaine-driven HIV-1 transcription and replication. PMID:25980739

  6. Alterations in leukocyte transcriptional control pathway activity associated with major depressive disorder and antidepressant treatment.

    Science.gov (United States)

    Mellon, S H; Wolkowitz, O M; Schonemann, M D; Epel, E S; Rosser, R; Burke, H B; Mahan, L; Reus, V I; Stamatiou, D; Liew, C-C; Cole, S W

    2016-05-24

    Major depressive disorder (MDD) is associated with a significantly elevated risk of developing serious medical illnesses such as cardiovascular disease, immune impairments, infection, dementia and premature death. Previous work has demonstrated immune dysregulation in subjects with MDD. Using genome-wide transcriptional profiling and promoter-based bioinformatic strategies, we assessed leukocyte transcription factor (TF) activity in leukocytes from 20 unmedicated MDD subjects versus 20 age-, sex- and ethnicity-matched healthy controls, before initiation of antidepressant therapy, and in 17 of the MDD subjects after 8 weeks of sertraline treatment. In leukocytes from unmedicated MDD subjects, bioinformatic analysis of transcription control pathway activity indicated an increased transcriptional activity of cAMP response element-binding/activating TF (CREB/ATF) and increased activity of TFs associated with cellular responses to oxidative stress (nuclear factor erythroid-derived 2-like 2, NFE2l2 or NRF2). Eight weeks of antidepressant therapy was associated with significant reductions in Hamilton Depression Rating Scale scores and reduced activity of NRF2, but not in CREB/ATF activity. Several other transcriptional regulation pathways, including the glucocorticoid receptor (GR), nuclear factor kappa-B cells (NF-κB), early growth response proteins 1-4 (EGR1-4) and interferon-responsive TFs, showed either no significant differences as a function of disease or treatment, or activities that were opposite to those previously hypothesized to be involved in the etiology of MDD or effective treatment. Our results suggest that CREB/ATF and NRF2 signaling may contribute to MDD by activating immune cell transcriptome dynamics that ultimately influence central nervous system (CNS) motivational and affective processes via circulating mediators.

  7. A novel Toxoplasma gondii nuclear factor TgNF3 is a dynamic chromatin-associated component, modulator of nucleolar architecture and parasite virulence.

    Directory of Open Access Journals (Sweden)

    Alejandro Olguin-Lamas

    2011-03-01

    Full Text Available In Toxoplasma gondii, cis-acting elements present in promoter sequences of genes that are stage-specifically regulated have been described. However, the nuclear factors that bind to these cis-acting elements and regulate promoter activities have not been identified. In the present study, we performed affinity purification, followed by proteomic analysis, to identify nuclear factors that bind to a stage-specific promoter in T. gondii. This led to the identification of several nuclear factors in T. gondii including a novel factor, designated herein as TgNF3. The N-terminal domain of TgNF3 shares similarities with the N-terminus of yeast nuclear FK506-binding protein (FKBP, known as a histone chaperone regulating gene silencing. Using anti-TgNF3 antibodies, HA-FLAG and YFP-tagged TgNF3, we show that TgNF3 is predominantly a parasite nucleolar, chromatin-associated protein that binds specifically to T. gondii gene promoters in vivo. Genome-wide analysis using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq identified promoter occupancies by TgNF3. In addition, TgNF3 has a direct role in transcriptional control of genes involved in parasite metabolism, transcription and translation. The ectopic expression of TgNF3 in the tachyzoites revealed dynamic changes in the size of the nucleolus, leading to a severe attenuation of virulence in vivo. We demonstrate that TgNF3 physically interacts with H3, H4 and H2A/H2B assembled into bona fide core and nucleosome-associated histones. Furthermore, TgNF3 interacts specifically to histones in the context of stage-specific gene silencing of a promoter that lacks active epigenetic acetylated histone marks. In contrast to virulent tachyzoites, which express the majority of TgNF3 in the nucleolus, the protein is exclusively located in the cytoplasm of the avirulent bradyzoites. We propose a model where TgNF3 acts essentially to coordinate nucleolus and nuclear functions by modulating

  8. Reconsolidation or extinction: transcription factor switch in the determination of memory course after retrieval.

    Science.gov (United States)

    de la Fuente, Verónica; Freudenthal, Ramiro; Romano, Arturo

    2011-04-13

    In fear conditioning, aversive stimuli are readily associated with contextual features. A brief reexposure to the training context causes fear memory reconsolidation, whereas a prolonged reexposure induces memory extinction. The regulation of hippocampal gene expression plays a key role in contextual memory consolidation and reconsolidation. However, the mechanisms that determine whether memory will reconsolidate or extinguish are not known. Here, we demonstrate opposing roles for two evolutionarily related transcription factors in the mouse hippocampus. We found that nuclear factor-κB (NF-κB) is required for fear memory reconsolidation. Conversely, calcineurin phosphatase inhibited NF-κB and induced nuclear factor of activated T-cells (NFAT) nuclear translocation in the transition between reconsolidation and extinction. Accordingly, the hippocampal inhibition of both calcineurin and NFAT independently impaired memory extinction, whereas inhibition of NF-κB enhanced memory extinction. These findings represent the first insight into the molecular mechanisms that determine memory reprocessing after retrieval, supporting a transcriptional switch that directs memory toward reconsolidation or extinction. The precise molecular characterization of postretrieval processes has potential importance to the development of therapeutic strategies for fear memory disorders.

  9. Hypoxia and Inflammation in Cancer, Focus on HIF and NF-κB

    Directory of Open Access Journals (Sweden)

    Laura D’Ignazio

    2017-05-01

    Full Text Available Cancer is often characterised by the presence of hypoxia and inflammation. Paramount to the mechanisms controlling cellular responses under such stress stimuli, are the transcription factor families of Hypoxia Inducible Factor (HIF and Nuclear Factor of κ-light-chain-enhancer of activated B cells (NF-κB. Although, a detailed understating of how these transcription factors respond to their cognate stimulus is well established, it is now appreciated that HIF and NF-κB undergo extensive crosstalk, in particular in pathological situations such as cancer. Here, we focus on the current knowledge on how HIF is activated by inflammation and how NF-κB is modulated by hypoxia. We summarise the evidence for the possible mechanism behind this activation and how HIF and NF-κB function impacts cancer, focusing on colorectal, breast and lung cancer. We discuss possible new points of therapeutic intervention aiming to harness the current understanding of the HIF-NF-κB crosstalk.

  10. A mechanistic overview of herbal medicine and botanical compounds to target transcriptional factors in Breast cancer.

    Science.gov (United States)

    Zhao, Yingke; Liu, Yue

    2018-04-01

    The abnormalities of transcription factors, such as NF-κB, STAT, estrogen receptor, play a critical role in the initiation and progression of breast cancer. Due to the limitation of current treatment, transcription factors could be promising therapeutic targets, which have received close attention. In this review, we introduced herbal medicines, as well as botanical compounds that had been verified with anti-tumor properties via regulating transcription factors. Herbs, compounds, as well as formulae reported with various transcriptional targets, were summarized thoroughly, to provide implication for the future research on basic experiment and clinical application. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. CAPERalpha is a novel Rel-TAD-interacting factor that inhibits lymphocyte transformation by the potent Rel/NF-kappaB oncoprotein v-Rel.

    Science.gov (United States)

    Dutta, Jui; Fan, Gaofeng; Gélinas, Céline

    2008-11-01

    The Rel/NF-kappaB transcription factors are constitutively activated in many human cancers. The Rel proteins in this family are implicated in leukemia/lymphomagenesis, but the mechanism is not completely understood. Previous studies showed that the transcription activation domains (TADs) of the viral oncoprotein v-Rel and its cellular Rel/NF-kappaB homologues c-Rel and RelA are key determinants of their different transforming activities in primary lymphocytes. Substitution of a Rel TAD for that of RelA conferred a strong transforming phenotype upon RelA, which otherwise failed to transform cells. To gain insights into protein interactions that influence cell transformation by the Rel TADs, we identified factors that interact with the TAD of v-Rel, the most oncogenic member of the Rel/NF-kappaB family. We report that the coactivator for transcription factors AP-1 and estrogen receptors, CAPERalpha, interacts with the v-Rel TAD and potently synergizes v-Rel-mediated transactivation. Importantly, coexpression of CAPERalpha markedly reduced and delayed v-Rel's transforming activity in primary lymphocytes, whereas a dominant-negative mutant enhanced the kinetics of v-Rel-mediated transformation. Furthermore, small interfering RNA-mediated knockdown of CAPERalpha in v-Rel-transformed lymphocytes significantly enhanced colony formation in soft agar. Since the potency of Rel-mediated transactivation is an important determinant of lymphocyte transformation, as is Rel's ability to induce transcriptional repression, these data suggest that CAPERalpha's interaction with the Rel TAD could modulate Rel/NF-kappaB's transforming activity by facilitating expression or dampening repression of specific gene subsets important for oncogenesis. Overall, this study identifies CAPERalpha as a new transcriptional coregulator for v-Rel and reveals an important role in modulating Rel's oncogenic activity.

  12. In vivo identification of promoter elements and transcription factors mediating activation of hepatic HMG-CoA reductase by T{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Boone, Lindsey R.; Niesen, Melissa I. [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL (United States); Jaroszeski, Mark [Department of Chemical and Biomedical Engineering, College of Engineering, University of South Florida, Tampa, FL (United States); Ness, Gene C., E-mail: gness@hsc.usf.edu [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL (United States)

    2009-07-31

    The promoter elements and transcription factors necessary for triiodothyronine (T{sub 3}) induction of hepatic HMG-CoA reductase (HMGR) were investigated by transfecting rat livers with wild type and mutant HMGR promoter-luciferase constructs using in vivo electroporation. Mutations in the sterol response element (SRE), nuclear factor-y (NF-Y) site, and the newly identified upstream transcription factor-2 (USF-2) site essentially abolished the T{sub 3} response. Chromatin immunoprecipitation (ChIP) analysis demonstrated that T{sub 3} treatment caused a 4-fold increase in in vivo binding of USF-2 to the HMGR promoter. Co-transfection of the wild type HMGR promoter with siRNAs to USF-2, SREBP-2, or NF-Y nearly abolished the T{sub 3} induction, as measured by promoter activity. These data provide in vivo evidence for functional roles for USF-2, SREBP-2, and NF-Y in mediating the T{sub 3}-induction of hepatic HMGR transcription.

  13. NF-kappaB signaling: a tale of two pathways in skeletal myogenesis.

    Science.gov (United States)

    Bakkar, Nadine; Guttridge, Denis C

    2010-04-01

    NF-kappaB is a ubiquitiously expressed transcription factor that plays vital roles in innate immunity and other processes involving cellular survival, proliferation, and differentiation. Activation of NF-kappaB is controlled by an IkappaB kinase (IKK) complex that can direct either canonical (classical) NF-kappaB signaling by degrading the IkappaB inhibitor and releasing p65/p50 dimers to the nucleus, or causes p100 processing and nuclear translocation of RelB/p52 via a noncanonical (alternative) pathway. Under physiological conditions, NF-kappaB activity is transiently regulated, whereas constitutive activation of this transcription factor typically in the classical pathway is associated with a multitude of disease conditions, including those related to skeletal muscle. How NF-kappaB functions in muscle diseases is currently under intense investigation. Insight into this role of NF-kappaB may be gained by understanding at a more basic level how this transcription factor contributes to skeletal muscle cell differentiation. Recent data from knockout mice support that the classical NF-kappaB pathway functions as an inhibitor of skeletal myogenesis and muscle regeneration acting through multiple mechanisms. In contrast, alternative NF-kappaB signaling does not appear to be required for myofiber conversion, but instead functions in myotube homeostasis by regulating mitochondrial biogenesis. Additional knowledge of these signaling pathways in skeletal myogenesis should aid in the development of specific inhibitors that may be useful in treatments of muscle disorders.

  14. Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Li Xu

    Full Text Available Members of the plant NUCLEAR FACTOR Y (NF-Y family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola, each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14 were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12 and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14 were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12 and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14 and two NF-YC members (BnNF-YC2 and BnNF-YC3 were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides

  15. Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

    Science.gov (United States)

    Xu, Li; Lin, Zhongyuan; Tao, Qing; Liang, Mingxiang; Zhao, Gengmao; Yin, Xiangzhen; Fu, Ruixin

    2014-01-01

    Members of the plant NUCLEAR FACTOR Y (NF-Y) family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola), each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14) were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12) and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14) were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12) and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14) and two NF-YC members (BnNF-YC2 and BnNF-YC3) were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides insight into

  16. Complex formation of p65/RelA with nuclear Akt1 for enhanced transcriptional activation of NF-κB

    International Nuclear Information System (INIS)

    Kwon, Osong; Kim, Kyung A; He, Long; Jung, Mira; Jeong, Sook Jung; Ahn, Jong Seog; Kim, Bo Yeon

    2008-01-01

    Akt1 was revealed to interact with Ki-Ras in the cytoplasm of Ki-Ras-transformed human prostate epithelial cells, 267B1/K-ras. Moreover, p65/RelA in the nucleus was found to interact with both Ki-Ras and Akt1, suggesting the nuclear translocation of Akt1:Ki-Ras complex for NF- κB activation. In support of this, compared with wild type Akt1, the dominant negative Akt1 mutant was decreased in its nuclear expression, reducing the Ki-Ras-induced NF-κB transcriptional activation. Moreover, inhibitors of Ras (sulindac sulfide and farnesyltransferase inhibitor I) or PI3K/Akt (wortmannin), reduced the amounts of Akt1 and Ki-Ras in the nucleus as well as partial NF-κB activity. The complete inhibition of Ki-Ras-induced NF-κB activation, however, could only be obtained by combined treatment with wortmannin and proteasome inhibitor-1. Accordingly, clonogenic assay showed Akt1 contribution to IκBα-mediated NF-κB activation for oncogenic cell growth by Ki-Ras. Our data suggest a crucial role of Ki-Ras:Akt1 complex in NF-κB transcriptional activation and enhancement of cell survival

  17. Immunodeficiency associated with a nonsense mutation of IKBKB

    DEFF Research Database (Denmark)

    Nielsen, Christian; Jakobsen, Marianne A; Larsen, Martin Jakob

    2014-01-01

    We report an infant of consanguineous parents of Turkish decent with a novel immunodeficiency associated with homozygosity for a nonsense mutation of the gene encoding Inhibitor of nuclear factor kappa-B (NF-κB) kinase subunit beta (IKKβ). At five months, she presented with respiratory insufficie......We report an infant of consanguineous parents of Turkish decent with a novel immunodeficiency associated with homozygosity for a nonsense mutation of the gene encoding Inhibitor of nuclear factor kappa-B (NF-κB) kinase subunit beta (IKKβ). At five months, she presented with respiratory...... no explanation before whole exome sequencing revealed a novel mutation abrogating signaling through the canonical NF-κB pathway....

  18. Dietary blue pigments derived from genipin, attenuate inflammation by inhibiting LPS-induced iNOS and COX-2 expression via the NF-κB inactivation.

    Science.gov (United States)

    Wang, Qiang-Song; Xiang, Yaozu; Cui, Yuan-Lu; Lin, Ke-Ming; Zhang, Xin-Fang

    2012-01-01

    The edible blue pigments produced by gardenia fruits have been used as value-added colorants for foods in East Asia for 20 years. However, the biological activity of the blue pigments derived from genipin has not been reported. The anti-inflammatory effect of blue pigments was studied in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophage in vitro. The secretions of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) were inhibited in concentration-dependent manner by blue pigments. Real-time reverse-transcription polymerase chain reaction (Real-time RT-PCR) analyses demonstrated that the mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α) was inhibited, moreover, ELISA results showed that the productions of IL-6 and TNF-α were inhibited. Cell-based ELISA revealed the COX-2 protein expression was inhibited. The proteome profiler array showed that 12 cytokines and chemokines involved in the inflammatory process were down-regulated by blue pigments. Blue pigments inhibited the nuclear transcription factor kappa-B (NF-κB) activation induced by LPS, and this was associated with decreasing the DNA-binding activity of p65 and p50. Furthermore, blue pigments suppressed the degradation of inhibitor of κB (IκB) α, Inhibitor of NF-κB Kinase (IKK) α, IKK-β, and phosphorylation of IκB-α. The anti-inflammatory effect of blue pigments in vivo was studied in carrageenan-induced paw edema and LPS-injecting ICR mice. Finally, blue pigments significantly inhibited paw swelling and reduced plasma TNF-α and IL-6 production in vivo. These results suggest that the anti-inflammatory properties of blue pigments might be the results from the inhibition of iNOS, COX-2, IL-6, IL-1β, and TNF-α expression through the down-regulation of NF-κB activation, which will provide strong scientific evidence for the edible blue pigments to be developed as a new health-enhancing nutritional food

  19. Dietary blue pigments derived from genipin, attenuate inflammation by inhibiting LPS-induced iNOS and COX-2 expression via the NF-κB inactivation.

    Directory of Open Access Journals (Sweden)

    Qiang-Song Wang

    Full Text Available The edible blue pigments produced by gardenia fruits have been used as value-added colorants for foods in East Asia for 20 years. However, the biological activity of the blue pigments derived from genipin has not been reported.The anti-inflammatory effect of blue pigments was studied in lipopolysaccharide (LPS stimulated RAW 264.7 macrophage in vitro. The secretions of nitric oxide (NO and prostaglandin E(2 (PGE(2 were inhibited in concentration-dependent manner by blue pigments. Real-time reverse-transcription polymerase chain reaction (Real-time RT-PCR analyses demonstrated that the mRNA expression of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (COX-2, interleukin (IL-6, and tumor necrosis factor alpha (TNF-α was inhibited, moreover, ELISA results showed that the productions of IL-6 and TNF-α were inhibited. Cell-based ELISA revealed the COX-2 protein expression was inhibited. The proteome profiler array showed that 12 cytokines and chemokines involved in the inflammatory process were down-regulated by blue pigments. Blue pigments inhibited the nuclear transcription factor kappa-B (NF-κB activation induced by LPS, and this was associated with decreasing the DNA-binding activity of p65 and p50. Furthermore, blue pigments suppressed the degradation of inhibitor of κB (IκB α, Inhibitor of NF-κB Kinase (IKK α, IKK-β, and phosphorylation of IκB-α. The anti-inflammatory effect of blue pigments in vivo was studied in carrageenan-induced paw edema and LPS-injecting ICR mice. Finally, blue pigments significantly inhibited paw swelling and reduced plasma TNF-α and IL-6 production in vivo.These results suggest that the anti-inflammatory properties of blue pigments might be the results from the inhibition of iNOS, COX-2, IL-6, IL-1β, and TNF-α expression through the down-regulation of NF-κB activation, which will provide strong scientific evidence for the edible blue pigments to be developed as a new health-enhancing nutritional

  20. Krüppel-like factor 4, a novel transcription factor regulates microglial activation and subsequent neuroinflammation

    Directory of Open Access Journals (Sweden)

    Das Sulagna

    2010-10-01

    Full Text Available Abstract Background Activation of microglia, the resident macrophages of the central nervous system (CNS, is the hallmark of neuroinflammation in neurodegenerative diseases and other pathological conditions associated with CNS infection. The activation of microglia is often associated with bystander neuronal death. Nuclear factor-κB (NF-κB is one of the important transcription factors known to be associated with microglial activation which upregulates the expression of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (Cox-2 and other pro-inflammatory cytokines. Recent studies have focused on the role of Krüppel-like factor 4 (Klf4, one of the zinc-finger transcription factors, in mediating inflammation. However, these studies were limited to peripheral system and its role in CNS is not understood. Our studies focused on the possible role of Klf4 in mediating CNS inflammation. Methods For in vitro studies, mouse microglial BV-2 cell lines were treated with 500 ng/ml Salmonella enterica lipopolysacchride (LPS. Brain tissues were isolated from BALB/c mice administered with 5 mg/kg body weight of LPS. Expressions of Klf4, Cox-2, iNOS and pNF-κB were evaluated using western blotting, quantitative real time PCR, and reverse transcriptase polymerase chain reactions (RT-PCRs. Klf4 knockdown was carried out using SiRNA specific for Klf4 mRNA and luciferase assays and electromobility shift assay (EMSA were performed to study the interaction of Klf4 to iNOS promoter elements in vitro. Co-immunoprecipitation of Klf4 and pNF-κB was done in order to study a possible interaction between the two transcription factors. Results LPS stimulation increased Klf4 expression in microglial cells in a time- and dose-dependent manner. Knockdown of Klf4 resulted in decreased levels of the pro-inflammatory cytokines TNF-α, MCP-1 and IL-6, along with a significant decrease in iNOS and Cox-2 expression. NO production also decreased as a result of Klf4 knockdown

  1. WRI1-1, ABI5, NF-YA3 and NF-YC2 increase oil biosynthesis in coordination with hormonal signaling during fruit development in oil palm.

    Science.gov (United States)

    Yeap, Wan-Chin; Lee, Fong-Chin; Shabari Shan, Dilip Kumar; Musa, Hamidah; Appleton, David Ross; Kulaveerasingam, Harikrishna

    2017-07-01

    The oil biosynthesis pathway must be tightly controlled to maximize oil yield. Oil palm accumulates exceptionally high oil content in its mesocarp, suggesting the existence of a unique fruit-specific fatty acid metabolism transcriptional network. We report the complex fruit-specific network of transcription factors responsible for modulation of oil biosynthesis genes in oil palm mesocarp. Transcriptional activation of EgWRI1-1 encoding a key master regulator that activates expression of oil biosynthesis genes, is activated by three ABA-responsive transcription factors, EgNF-YA3, EgNF-YC2 and EgABI5. Overexpression of EgWRI1-1 and its activators in Arabidopsis accelerated flowering, increased seed size and oil content, and altered expression levels of oil biosynthesis genes. Protein-protein interaction experiments demonstrated that EgNF-YA3 interacts directly with EgWRI1-1, forming a transcription complex with EgNF-YC2 and EgABI5 to modulate transcription of oil biosynthesis pathway genes. Furthermore, EgABI5 acts downstream of EgWRKY40, a repressor that interacts with EgWRKY2 to inhibit the transcription of oil biosynthesis genes. We showed that expression of these activators and repressors in oil biosynthesis can be induced by phytohormones coordinating fruit development in oil palm. We propose a model highlighting a hormone signaling network coordinating fruit development and fatty acid biosynthesis. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  2. Molecular imaging of the transcription factor NF-κB, a primary regulator of stress response

    International Nuclear Information System (INIS)

    Carlsen, Harald; Alexander, George; Austenaa, Liv M.I.; Ebihara, Kanae; Blomhoff, Rune

    2004-01-01

    A wide range of environmental stress and human disorders involves inappropriate regulation of NF-κB, including cancers and numerous inflammatory conditions. We have developed transgenic mice that express luciferase under the control of NF-κB, enabling real-time non-invasive imaging of NF-κB activity in intact animals. We show that, in the absence of stimulation, strong, intrinsic luminescence is evident in lymph nodes in the neck region, thymus, and Peyer's patches. Treating mice with stressors, such as TNF-α, IL-1α, or lipopolysaccharide (LPS) increases the luminescence in a tissue-specific manner, with the strongest activity observable in the skin, lungs, spleen, Peyer's patches, and the wall of the small intestine. Liver, kidney, heart, muscle, and adipose tissue exhibit less intense activities. Exposure of the skin to a low dose of UV-B radiation increases luminescence in the exposed areas. In ocular experiments, LPS- and TNF-α injected NF-κB-luciferase transgenic mice exhibit a 20-40-fold increase in lens NF-κB activity, similar to other LPS- and TNF-α-responsive organs. Peak NF-κB activity occurs 6 h after injection of TNF-α and 12 h after injection of LPS. Peak activities occur, respectively, 3 and 6 h later than that in other tissues. Mice exposed to 360 J/m 2 of UV-B exhibit a 16-fold increase in NF-κB activity 6 h after exposure, characteristically similar to TNF-α-exposed mice. Thus, in NF-κB-luciferase transgenic mice, NF-κB activity also occurs in lens epithelial tissue and is activated when the intact mouse is exposed to classical stressors. Furthermore, as revealed by real-time non-invasive imaging, induction of chronic inflammation resembling rheumatoid arthritis produces strong NF-κB activity in the affected joints. Finally, we have used the model to demonstrate NF-κB regulation by manipulating the Vitamin A status in mice. NF-κB activity is elevated in mice fed a Vitamin A deficient (VAD) diet, and suppressed by surplus doses of

  3. NF-κB mediates the transcription of mouse calsarcin-1 gene, but not calsarcin-2, in C2C12 cells

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    Mu Yulian

    2007-03-01

    Full Text Available Abstract Background The calsarcins comprise a novel family of muscle-specific calcineurin-interaction proteins that play an important role in modulating both the function and substrate specificity of calcineurin in muscle cells. The expression of calsarcin-1 (CS-1 is restricted to slow-twitch skeletal muscle fibres, whereas that of both calsarcin-2 (CS-2 and calsarcin-3 (CS-3 is enriched in fast-twitch fibres. However, the transcriptional control of this selective expression has not been previously elucidated. Results Our real-time RT-PCR analyses suggest that the expression of CS-1 and CS-2 is increased during the myogenic differentiation of mouse C2C12 cells. Promoter deletion analysis further suggests that an NF-κB binding site within the CS-1 promoter is responsible for the up-regulation of CS-1 transcription, but no similar mechanism was evident for CS-2. These findings are further supported by the results of EMSA analysis, as well as by overexpression and inhibition experiments in which NF-κB function was blocked by treatment with its inhibitor, PDTC. In addition, the overexpression of NFATc4 induces both the CS-1 and CS-2 promoters, whereas MEF2C only activates CS-1. Conclusion Our present data suggest that NF-κB is required for the transcription of mouse CS-1 but not CS-2, and that the regulation of the calsarcins is mediated also by the NFAT and MEF2 transcription factors. These results provide new insights into the molecular mechanisms governing transcription in specific muscle fibre cells. The calsarcins may also serve as a valuable mechanistic tool to better understand the regulation of calcineurin signalling during muscle differentiation.

  4. Regulation of Gene Expression with Double-Stranded Phosphorothioate Oligonucleotides

    Science.gov (United States)

    Bielinska, Anna; Shivdasani, Ramesh A.; Zhang, Liquan; Nabel, Gary J.

    1990-11-01

    Alteration of gene transcription by inhibition of specific transcriptional regulatory proteins is necessary for determining how these factors participate in cellular differentiation. The functions of these proteins can be antagonized by several methods, each with specific limitations. Inhibition of sequence-specific DNA-binding proteins was achieved with double-stranded (ds) phosphorothioate oligonucleotides that contained octamer or kappaB consensus sequences. The phosphorothioate oligonucleotides specifically bound either octamer transcription factor or nuclear factor (NF)-kappaB. The modified oligonucleotides accumulated in cells more effectively than standard ds oligonucleotides and modulated gene expression in a specific manner. Octamer-dependent activation of a reporter plasmid or NF-kappaB-dependent activation of the human immunodeficiency virus (HIV) enhancer was inhibited when the appropriate phosphorothioate oligonucleotide was added to a transiently transfected B cell line. Addition of phosphorothioate oligonucleotides that contained the octamer consensus to Jurkat T leukemia cells inhibited interleukin-2 (IL-2) secretion to a degree similar to that observed with a mutated octamer site in the IL-2 enhancer. The ds phosphorothioate oligonucleotides probably compete for binding of specific transcription factors and may provide anti-viral, immunosuppressive, or other therapeutic effects.

  5. Host transcription factors in the immediate pro-inflammatory response to the parasitic mite Psoroptes ovis.

    Directory of Open Access Journals (Sweden)

    Stewart T G Burgess

    Full Text Available BACKGROUND: Sheep scab, caused by infestation with the ectoparasitic mite Psoroptes ovis, results in the rapid development of cutaneous inflammation and leads to the crusted skin lesions characteristic of the disease. We described previously the global host transcriptional response to infestation with P. ovis, elucidating elements of the inflammatory processes which lead to the development of a rapid and profound immune response. However, the mechanisms by which this response is instigated remain unclear. To identify novel methods of intervention a better understanding of the early events involved in triggering the immune response is essential. The objective of this study was to gain a clearer understanding of the mechanisms and signaling pathways involved in the instigation of the immediate pro-inflammatory response. RESULTS: Through a combination of transcription factor binding site enrichment and pathway analysis we identified key roles for a number of transcription factors in the instigation of cutaneous inflammation. In particular, defined roles were elucidated for the transcription factors NF-kB and AP-1 in the orchestration of the early pro-inflammatory response, with these factors being implicated in the activation of a suite of inflammatory mediators. CONCLUSIONS: Interrogation of the host temporal response to P. ovis infestation has enabled the further identification of the mechanisms underlying the development of the immediate host pro-inflammatory response. This response involves key regulatory roles for the transcription factors NF-kB and AP-1. Pathway analysis demonstrated that the activation of these transcription factors may be triggered following a host LPS-type response, potentially involving TLR4-signalling and also lead to the intriguing possibility that this could be triggered by a P. ovis allergen.

  6. Inhibition of the transcription factor c-Jun by the MAPK family, and not the NF-κB pathway, suggests that peanut extract has anti-inflammatory properties.

    Science.gov (United States)

    Catalán, Úrsula; Fernández-Castillejo, Sara; Anglès, Neus; Morelló, Jose Ramón; Yebras, Martí; Solà, Rosa

    2012-10-01

    Tumor necrosis factor-α (TNF-α) is involved in inflammatory responses in atherosclerosis. We propose an in vitro cellular assay to evaluate the anti-inflammatory mechanisms of potential modifiers such as food extracts. In the current model we assessed an anti-inflammatory effect of polyphenol-rich peanut extract in lipopolysaccharide (LPS)-induced THP-1 monocytes. THP-1 monocytes were incubated with peanut extract (5, 25, 50 and 100 μg/mL) consisting of 39% flavonols, 37% flavanols and 24% phenolic acid (or BAY 11-7082 (5 μM) as experiment control) for 1 h and then stimulated with LPS (500 ng/mL) for 4 h. Cytotoxicity was measured as lactate dehydrogenase (LDH) activity release. NF-κB and MAPK family were determined by TransAm kit while TNF-α mRNA levels and its mRNA stability by RT-PCR. Intra- and extracellular TNF-α protein was measured by ELISA, and TNF-α converting enzyme (TACE) activity by a fluorimetric assay. Peanut extract inhibited the maximal LPS-induced extracellular TNF-α protein secretion by 18%, 29% and 47% at 25, 50 and 100 μg/mL, respectively (P<0.05). LPS stimulation revealed that 85% of TNF-α was released extracellularly while 15% remained intracellular. Peanut extract did not modify NF-κB but, instead, reduced c-Jun transcription factor activity (P<0.05), decreased TNF-α mRNA (albeit non-significantly) and had no effect on mRNA stability and TACE activity. Polyphenol-rich peanut extract reduces extracellular TNF-α protein by inhibiting c-Jun transcription factor from MAPK family, suggesting an anti-inflammatory effect. The proposed THP-1 monocyte model could be used to assess food extract impact (site and size effects) on the inflammation pathway. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Blocking NF-κB: an inflammatory issue.

    Science.gov (United States)

    Rahman, Arshad; Fazal, Fabeha

    2011-11-01

    The nuclear factor (NF)-κB is considered the master regulator of inflammatory responses. Studies in mouse models have established this transcription factor as an important mediator of many inflammatory disease states, including pulmonary diseases such as acute lung injury and acute respiratory distress syndrome. Endothelial cells provide the first barrier for leukocytes migrating to the inflamed sites and hence offer an attractive cellular context for targeting NF-κB for treatment of these diseases. However, recent studies showing that NF-κB also plays an important role in resolution phase of inflammation and in tissue repair and homeostasis have challenged the view of therapeutic inhibition of NF-κB. This article reviews the regulation of NF-κB in the context of endothelial cell signaling and provides a perspective on why "dampening" rather than "abolishing" NF-κB activation may be a safe and effective treatment strategy for inflammation-associated pulmonary and other inflammatory diseases.

  8. JANEX-1, a JAK3 inhibitor, protects pancreatic islets from cytokine toxicity through downregulation of NF-{kappa}B activation and the JAK/STAT pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Na; Kim, Eun-Kyung; Song, Mi-Young [Department of Biochemistry, Medical School and Diabetes Research Center, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Choi, Ha-Na; Moon, Woo Sung [Department of Pathology, Medical School and Diabetes Research Center, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Park, Sung-Joo [Department of Herbology, School of Oriental Medicine, Wonkwang University, Iksan, Jeonbuk 570-749 (Korea, Republic of); Park, Jin-Woo [Department of Biochemistry, Medical School and Diabetes Research Center, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Kwon, Kang-Beom, E-mail: desson@wonkwang.ac.kr [Department of Physiology, School of Oriental Medicine, Wonkwang University, Iksan, Jeonbuk 570-749 (Korea, Republic of); Park, Byung-Hyun, E-mail: bhpark@chonbuk.ac.kr [Department of Biochemistry, Medical School and Diabetes Research Center, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

    2009-07-15

    JANEX-1/WHI-P131, a selective Janus kinase 3 (JAK3) inhibitor, has been shown to delay the onset of diabetes in the NOD mouse model. However, the molecular mechanism by which JANEX-1 protects pancreatic {beta}-cells is unknown. In the current study, we investigated the role of JANEX-1 on interleukin (IL)-1{beta} and interferon (IFN)-{gamma}-induced {beta}-cell damage using isolated islets. JANEX-1-pretreated islets showed resistance to cytokine toxicity, namely suppressed nitric oxide (NO) production, reduced inducible form of NO synthase (iNOS) expression, and decreased islet destruction. The molecular mechanism by which JANEX-1 inhibits iNOS expression was mediated through suppression of the nuclear factor {kappa}B (NF-{kappa}B) and JAK/signal transducer and activator of transcription (STAT) pathways. Islets treated with the cytokines downregulated the protein levels of suppressor of cytokine signaling (SOCS)-1 and SOCS-3, but pretreatment with JANEX-1 attenuated these decreases. Additionally, islets from JAK3{sup -/-} mice were more resistant to cytokine toxicity than islets from control mice. These results demonstrate that JANEX-1 protects {beta}-cells from cytokine toxicity through suppression of the NF-{kappa}B and JAK/STAT pathways and upregulation of SOCS proteins, suggesting that JANEX-1 may be used to preserve functional {beta}-cell mass.

  9. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    International Nuclear Information System (INIS)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei; Shen, Yu; Cai, Xiaoli; Zhang, Xiaodong; Ye, Lihong

    2013-01-01

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB) plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells

  10. The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingyi; Zhao, Yu; Li, Leilei; Shen, Yu; Cai, Xiaoli [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [Department of Cancer Research, Institute for Molecular Biology, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ye, Lihong, E-mail: yelihong@nankai.edu.cn [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2013-05-03

    Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB) plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells.

  11. Identification and characterization of NF-YB family genes in tung tree.

    Science.gov (United States)

    Yang, Susu; Wang, Yangdong; Yin, Hengfu; Guo, Haobo; Gao, Ming; Zhu, Huiping; Chen, Yicun

    2015-12-01

    The NF-YB transcription factor gene family encodes a subunit of the CCAAT box-binding factor (CBF), a highly conserved trimeric activator that strongly binds to the CCAAT box promoter element. Studies on model plants have shown that NF-YB proteins participate in important developmental and physiological processes, but little is known about NF-YB proteins in trees. Here, we identified seven NF-YB transcription factor-encoding genes in Vernicia fordii, an important oilseed tree in China. A phylogenetic analysis separated the genes into two groups; non-LEC1 type (VfNF-YB1, 5, 7, 9, 11, 13) and LEC1-type (VfNF-YB 14). A gene structure analysis showed that VfNF-YB 5 has three introns and the other genes have no introns. The seven VfNF-YB sequences contain highly conserved domains, a disordered region at the N terminus, and two long helix structures at the C terminus. Phylogenetic analyses showed that VfNF-YB family genes are highly homologous to GmNF-YB genes, and many of them are closely related to functionally characterized NF-YBs. In expression analyses of various tissues (root, stem, leaf, and kernel) and the root during pathogen infection, VfNF-YB1, 5, and 11 were dominantly expressed in kernels, and VfNF-YB7 and 9 were expressed only in the root. Different VfNF-YB family genes showed different responses to pathogen infection, suggesting that they play different roles in the pathogen response. Together, these findings represent the first extensive evaluation of the NF-YB family in tung tree and provide a foundation for dissecting the functions of VfNF-YB genes in seed development, stress adaption, fatty acid synthesis, and pathogen response.

  12. Modulation of transcription factors by curcumin.

    Science.gov (United States)

    Shishodia, Shishir; Singh, Tulika; Chaturvedi, Madan M

    2007-01-01

    Curcumin is the active ingredient of turmeric that has been consumed as a dietary spice for ages. Turmeric is widely used in traditional Indian medicine to cure biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism, and sinusitis. Extensive investigation over the last five decades has indicated that curcumin reduces blood cholesterol, prevents low-density lipoprotein oxidation, inhibits platelet aggregation, suppresses thrombosis and myocardial infarction, suppresses symptoms associated with type II diabetes, rheumatoid arthritis, multiple sclerosis, and Alzheimer's disease, inhibits HIV replication, enhances wound healing, protects from liver injury, increases bile secretion, protects from cataract formation, and protects from pulmonary toxicity and fibrosis. Evidence indicates that the divergent effects of curcumin are dependent on its pleiotropic molecular effects. These include the regulation of signal transduction pathways and direct modulation of several enzymatic activities. Most of these signaling cascades lead to the activation of transcription factors. Curcumin has been found to modulate the activity of several key transcription factors and, in turn, the cellular expression profiles. Curcumin has been shown to elicit vital cellular responses such as cell cycle arrest, apoptosis, and differentiation by activating a cascade of molecular events. In this chapter, we briefly review the effects of curcumin on transcription factors NF-KB, AP-1, Egr-1, STATs, PPAR-gamma, beta-catenin, nrf2, EpRE, p53, CBP, and androgen receptor (AR) and AR-related cofactors giving major emphasis to the molecular mechanisms of its action.

  13. NFAT5 participates in seawater inhalation-induced acute lung injury via modulation of NF-κB activity

    Science.gov (United States)

    Li, Congcong; Liu, Manling; Bo, Liyan; Liu, Wei; Liu, Qingqing; Chen, Xiangjun; Xu, Dunquan; Li, Zhichao; Jin, Faguang

    2016-01-01

    Nuclear factor of activated T cells 5 (NFAT5) is a transcription factor that can be activated by extracellular tonicity. It has been reported that NFAT5 may increase the transcription of certain osmoprotective genes in the renal system, and the aim of the current study was to explore the role of NFAT5 in seawater inhalation-induced acute lung injury. Though establishing the model of seawater inhalation-induced acute lung injury, it was demonstrated that seawater inhalation enhanced the transcription and protein expression of NFAT5 (evaluated by reverse transcription-polymerase chain reaction, immunohistochemistry stain and western blotting) and activation of nuclear factor (NF)-κB (evaluated by western blotting and mRNA expression levels of three NF-κB-dependent genes) both in lung tissue and rat alveolar macrophage cells (NR8383 cells). When expression of NFAT5 was reduced in NR8383 cells using an siRNA targeted to NFAT5, the phosphorylation of NF-κB and transcription of NF-κB-dependent genes were significantly reduced. In addition, the elevated content of certain inflammatory cytokines [tumor necrosis factor α, interleukin (IL)-1 and IL-8] were markedly reduced. In conclusion, NFAT5 serves an important pathophysiological role in seawater inhalation-induced acute lung injury by modulating NF-κB activity, and these data suggest that NFAT5 may be a promising therapeutic target. PMID:27779669

  14. Diclofenac inhibits tumor necrosis factor-α-induced nuclear factor-κB activation causing synergistic hepatocyte apoptosis.

    Science.gov (United States)

    Fredriksson, Lisa; Herpers, Bram; Benedetti, Giulia; Matadin, Quraisha; Puigvert, Jordi C; de Bont, Hans; Dragovic, Sanja; Vermeulen, Nico P E; Commandeur, Jan N M; Danen, Erik; de Graauw, Marjo; van de Water, Bob

    2011-06-01

    Drug-induced liver injury (DILI) is an important clinical problem. It involves crosstalk between drug toxicity and the immune system, but the exact mechanism at the cellular hepatocyte level is not well understood. Here we studied the mechanism of crosstalk in hepatocyte apoptosis caused by diclofenac and the proinflammatory cytokine tumor necrosis factor α (TNF-α). HepG2 cells were treated with diclofenac followed by TNF-α challenge and subsequent evaluation of necrosis and apoptosis. Diclofenac caused a mild apoptosis of HepG2 cells, which was strongly potentiated by TNF-α. A focused apoptosis machinery short interference RNA (siRNA) library screen identified that this TNF-α-mediated enhancement involved activation of caspase-3 through a caspase-8/Bid/APAF1 pathway. Diclofenac itself induced sustained activation of c-Jun N-terminal kinase (JNK) and inhibition of JNK decreased both diclofenac and diclofenac/TNF-α-induced apoptosis. Live cell imaging of GFPp65/RelA showed that diclofenac dampened the TNF-α-mediated nuclear factor kappaB (NF-κB) translocation oscillation in association with reduced NF-κB transcriptional activity. This was associated with inhibition by diclofenac of the TNF-α-induced phosphorylation of the inhibitor of NF-κB alpha (IκBα). Finally, inhibition of IκB kinase β (IKKβ) with BMS-345541 as well as stable lentiviral short hairpin RNA (shRNA)-based knockdown of p65/RelA sensitized hepatocytes towards diclofenac/TNF-α-induced cytotoxicity. Together, our data suggest a model whereby diclofenac-mediated stress signaling suppresses TNF-α-induced survival signaling routes and sensitizes cells to apoptosis. Copyright © 2011 American Association for the Study of Liver Diseases.

  15. Members of miR-169 family are induced by high salinity and transiently inhibit the NF-YA transcription factor

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    Lin Hongxuan

    2009-04-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are endogenously expressed small RNAs with a length of about 21 nt. MiRNAs silence their target genes at the post-transcriptional level. In plants, miRNAs play various developmental and physiological roles by cleavaging mRNAs predominantly. Drought and high salinity are the most severe environmental abiotic stresses and cause crop losses all over the world. Results In this study, we identified miR-169g and miR-169n (o as high salinity-responsive miRNAs in rice. MiR-169n and miR169o were in a miRNA cluster with a distance of 3707 base pairs (bp. The high degree of conservation and close phylogenic distance of pre-miR-169n and pre-miR-169o indicated that they were derived from a very recent tandem duplication evolutionary event. The existence of a cis-acting abscisic acid responsive element (ABRE in the upstream region of miR-169n (o suggested that miR-169n (o may be regulated by ABA. In our previous study, we found that miR-169g was induced by the osmotic stress caused by drought via a dehydration-responsive element (DRE. Thus, our data showed that there were both overlapping and distinct responses of the miR-169 family to drought and salt stresses. We also showed that these miR-169 members selectively cleaved one of the NF-YA genes, Os03g29760, which is a CCAAT-box binding transcription factor and participates in transcriptional regulation of large number genes. Finally, we found one or more ath-miR-169 member that was also induced by high salinity. Conclusion We identified members of the miR-169 family as salt-induced miRNAs and analyzed their evolution, gene organization, expression, transcriptional regulation motif and target gene. Our data also indicated that the salt-induction of some miR-169 members was a general property in plants.

  16. Members of miR-169 family are induced by high salinity and transiently inhibit the NF-YA transcription factor.

    Science.gov (United States)

    Zhao, Botao; Ge, Liangfa; Liang, Ruqiang; Li, Wei; Ruan, Kangcheng; Lin, Hongxuan; Jin, Youxin

    2009-04-08

    MicroRNAs (miRNAs) are endogenously expressed small RNAs with a length of about 21 nt. MiRNAs silence their target genes at the post-transcriptional level. In plants, miRNAs play various developmental and physiological roles by cleavaging mRNAs predominantly. Drought and high salinity are the most severe environmental abiotic stresses and cause crop losses all over the world. In this study, we identified miR-169g and miR-169n (o) as high salinity-responsive miRNAs in rice. MiR-169n and miR169o were in a miRNA cluster with a distance of 3707 base pairs (bp). The high degree of conservation and close phylogenic distance of pre-miR-169n and pre-miR-169o indicated that they were derived from a very recent tandem duplication evolutionary event. The existence of a cis-acting abscisic acid responsive element (ABRE) in the upstream region of miR-169n (o) suggested that miR-169n (o) may be regulated by ABA. In our previous study, we found that miR-169g was induced by the osmotic stress caused by drought via a dehydration-responsive element (DRE). Thus, our data showed that there were both overlapping and distinct responses of the miR-169 family to drought and salt stresses. We also showed that these miR-169 members selectively cleaved one of the NF-YA genes, Os03g29760, which is a CCAAT-box binding transcription factor and participates in transcriptional regulation of large number genes. Finally, we found one or more ath-miR-169 member that was also induced by high salinity. We identified members of the miR-169 family as salt-induced miRNAs and analyzed their evolution, gene organization, expression, transcriptional regulation motif and target gene. Our data also indicated that the salt-induction of some miR-169 members was a general property in plants.

  17. Keap1 silencing boosts lipopolysaccharide-induced transcription of interleukin 6 via activation of nuclear factor κB in macrophages

    International Nuclear Information System (INIS)

    Lv, Peng; Xue, Peng; Dong, Jian; Peng, Hui; Clewell, Rebecca; Wang, Aiping; Wang, Yue; Peng, Shuangqing; Qu, Weidong; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

    2013-01-01

    Interleukin-6 (IL6) is a multifunctional cytokine that regulates immune and inflammatory responses. Multiple transcription factors, including nuclear factor κB (NF-κB) and nuclear factor E2-related factor 2 (Nrf2), regulate IL6 transcription. Kelch-like ECH-associated protein 1 (Keap1) is a substrate adaptor protein for the Cullin 3-dependent E3 ubiquitin ligase complex, which regulates the degradation of many proteins, including Nrf2 and IκB kinase β (IKKβ). Here, we found that stable knockdown of Keap1 (Keap1-KD) in RAW 264.7 (RAW) mouse macrophages and human monocyte THP-1 cells significantly increased expression of Il6, and Nrf2-target genes, under basal and lipopolysaccharide (LPS, 0.001–0.1 μg/ml)-challenged conditions. However, Nrf2 activation alone, by tert-butylhydroquinone treatment of RAW cells, did not increase expression of Il6. Compared to cells transduced with scrambled non-target negative control shRNA, Keap1-KD RAW cells showed enhanced protein levels of IKKβ and increased expression and phosphorylation of NF-κB p65 under non-stressed and LPS-treated conditions. Because the expression of Il6 in Keap1-KD RAW cells was significantly attenuated by silencing of Ikkβ, but not Nrf2, it appears that stabilized IKKβ is responsible for the enhanced transactivation of Il6 in Keap1-KD cells. This study demonstrated that silencing of Keap1 in macrophages boosts LPS-induced transcription of Il6 via NF-κB activation. Given the importance of IL6 in the inflammatory response, the Keap1–IKKβ–NF-κB pathway may be a novel target for treatment and prevention of inflammation and associated disorders. - Highlights: • Knockdown of Keap1 increases expression of Il6 in macrophages. • Silencing of Keap1 results in protein accumulation of IKKβ and NF-κB p65. • Induction of Il6 resulting from Keap1 silencing is attributed to NF-κB activation

  18. Keap1 silencing boosts lipopolysaccharide-induced transcription of interleukin 6 via activation of nuclear factor κB in macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Peng [Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Xue, Peng; Dong, Jian [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Peng, Hui [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Evaluation and Research Center for Toxicology, Institute of Disease Control and Prevention, Academy of Military Medical Sciences (China); Clewell, Rebecca [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Wang, Aiping [Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Wang, Yue [Institute for Medical Device Standardization Administration, National Institutes for Food and Drug Control, Beijing (China); Peng, Shuangqing [Evaluation and Research Center for Toxicology, Institute of Disease Control and Prevention, Academy of Military Medical Sciences (China); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Zhang, Qiang; Andersen, Melvin E. [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jpi@thehamner.org [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States)

    2013-11-01

    Interleukin-6 (IL6) is a multifunctional cytokine that regulates immune and inflammatory responses. Multiple transcription factors, including nuclear factor κB (NF-κB) and nuclear factor E2-related factor 2 (Nrf2), regulate IL6 transcription. Kelch-like ECH-associated protein 1 (Keap1) is a substrate adaptor protein for the Cullin 3-dependent E3 ubiquitin ligase complex, which regulates the degradation of many proteins, including Nrf2 and IκB kinase β (IKKβ). Here, we found that stable knockdown of Keap1 (Keap1-KD) in RAW 264.7 (RAW) mouse macrophages and human monocyte THP-1 cells significantly increased expression of Il6, and Nrf2-target genes, under basal and lipopolysaccharide (LPS, 0.001–0.1 μg/ml)-challenged conditions. However, Nrf2 activation alone, by tert-butylhydroquinone treatment of RAW cells, did not increase expression of Il6. Compared to cells transduced with scrambled non-target negative control shRNA, Keap1-KD RAW cells showed enhanced protein levels of IKKβ and increased expression and phosphorylation of NF-κB p65 under non-stressed and LPS-treated conditions. Because the expression of Il6 in Keap1-KD RAW cells was significantly attenuated by silencing of Ikkβ, but not Nrf2, it appears that stabilized IKKβ is responsible for the enhanced transactivation of Il6 in Keap1-KD cells. This study demonstrated that silencing of Keap1 in macrophages boosts LPS-induced transcription of Il6 via NF-κB activation. Given the importance of IL6 in the inflammatory response, the Keap1–IKKβ–NF-κB pathway may be a novel target for treatment and prevention of inflammation and associated disorders. - Highlights: • Knockdown of Keap1 increases expression of Il6 in macrophages. • Silencing of Keap1 results in protein accumulation of IKKβ and NF-κB p65. • Induction of Il6 resulting from Keap1 silencing is attributed to NF-κB activation.

  19. Inhibition of nuclear factor kappa-B signaling reduces growth in medulloblastoma in vivo

    Directory of Open Access Journals (Sweden)

    Deckard Lindsey A

    2011-04-01

    Full Text Available Abstract Background Medulloblastoma is a highly malignant pediatric brain tumor that requires surgery, whole brain and spine irradiation, and intense chemotherapy for treatment. A more sophisticated understanding of the pathophysiology of medulloblastoma is needed to successfully reduce the intensity of treatment and improve outcomes. Nuclear factor kappa-B (NFκB is a signaling pathway that controls transcriptional activation of genes important for tight regulation of many cellular processes and is aberrantly expressed in many types of cancer. Methods To test the importance of NFκB to medulloblastoma cell growth, the effects of multiple drugs that inhibit NFκB, pyrrolidine dithiocarbamate, diethyldithiocarbamate, sulfasalazine, curcumin and bortezomib, were studied in medulloblastoma cell lines compared to a malignant glioma cell line and normal neurons. Expression of endogenous NFκB was investigated in cultured cells, xenograft flank tumors, and primary human tumor samples. A dominant negative construct for the endogenous inhibitor of NFκB, IκB, was prepared from medulloblastoma cell lines and flank tumors were established to allow specific pathway inhibition. Results We report high constitutive activity of the canonical NFκB pathway, as seen by Western analysis of the NFκB subunit p65, in medulloblastoma tumors compared to normal brain. The p65 subunit of NFκB is extremely highly expressed in xenograft tumors from human medulloblastoma cell lines; though, conversely, the same cells in culture have minimal expression without specific stimulation. We demonstrate that pharmacological inhibition of NFκB in cell lines halts proliferation and leads to apoptosis. We show by immunohistochemical stain that phosphorylated p65 is found in the majority of primary tumor cells examined. Finally, expression of a dominant negative form of the endogenous inhibitor of NFκB, dnIκB, resulted in poor xenograft tumor growth, with average tumor volumes

  20. Vitamin D inhibits the growth of and virulence factor gene expression by Porphyromonas gingivalis and blocks activation of the nuclear factor kappa B transcription factor in monocytes.

    Science.gov (United States)

    Grenier, D; Morin, M-P; Fournier-Larente, J; Chen, H

    2016-06-01

    Increasing evidence suggests that 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ), a fat-soluble secosteroid hormone, has a positive impact on periodontal health through diverse mechanisms. The present study was aimed at investigating the effect of 1,25(OH)2 D3 on the growth of and virulence factor gene expression by the periodontopathogenic bacterium Porphyromonas gingivalis. The effect of 1,25(OH)2 D3 on P. gingivalis-mediated activation of nuclear factor kappa B (NF-κB) transcription factor in monocytes was also assessed. A broth microdilution assay was used to determine the antibacterial activity of 1,25(OH)2 D3 . The modulation of virulence factor gene expression in P. gingivalis was assessed by quantitative reverse transcription-polymerase chain reaction. NF-κB activation was assessed using a human monocytic cell line stably transfected with a luciferase reporter containing NF-κB binding sites. Minimal inhibitory concentrations of 1,25(OH)2 D3 against P. gingivalis ranged from 3.125 to 6.25 μg/mL. Moreover, a partial synergistic effect was observed when 1,25(OH)2 D3 was used in association with metronidazole. 1,25(OH)2 D3 attenuated the virulence of P. gingivalis by reducing the expression of genes coding for important virulence factors, including adhesins (fimA, hagA and hagB) and proteinases (rgpA, rgpB and kgp). 1,25(OH)2 D3 dose-dependently prevented P. gingivalis-induced NF-κB activation in a monocyte model. Our study suggested that 1,25(OH)2 D3 selectively inhibits the growth of and virulence factor gene expression by P. gingivalis, in addition to attenuating NF-κB activation by this periodontopathogen. This dual action on P. gingivalis and the inflammatory response of host cells may be of particular interest with a view to developing a novel and inexpensive preventive/therapeutic strategy. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Synergistic activation of the CMV promoter by NF-κB P50 and PKG

    International Nuclear Information System (INIS)

    He Bin; Weber, Georg F.

    2004-01-01

    Several DNA binding NF-κB subunits are substrates for cGMP-dependent kinase (PKG) and their transactivation from cognate sites is induced by phosphorylation. This includes p50, which does not have a transcriptional activation domain and therefore needs to bind to other proteins to mediate gene expression. Here, we describe the synergistic transactivation by p50 and PKG from the CMV promoter. This is caused not only by phosphorylation of p50, leading to increased DNA binding, but also by PKG-dependent activation of CRE sites in the promoter. One of the CRE sites is located directly adjacent to a NF-κB site and is essential for p50-mediated induction of transcription. According to the binding of CREB to p50 in pull-down assays and according to the inhibition of p50-dependent transactivation by dominant-negative CREB, this reflects the formation of a transcription factor complex containing CREB and p50. The nuclear translocation of NF-κB is insufficient to distinguish among the multitude of promoters that harbor cognate recognition sites. The phosphorylation of multiple transcription factors by an upstream kinase, such as PKG, can lead to the formation of transcription factor complexes and differential transactivation from a subset of NF-κB sites. These interactions may be relevant for the activation of viral gene expression

  2. NF-kappaB in Lung Tumorigenesis

    International Nuclear Information System (INIS)

    Cai, Zhenjian; Tchou-Wong, Kam-Meng; Rom, William N.

    2011-01-01

    The development of lung cancer in humans can be divided into three steps initiation, promotion and progression. This process is driven by alterations in related signal transduction pathways. These pathways signal the aberrant activation of NF-kappaB, a transcription factor that regulates the expression of genes important for lung tumorigenesis. Our current knowledge about the role of the NF-kappaB signaling pathway in the development of lung cancer has been bolstered by animal models demonstrating the connection between K-ras and tobacco induced lung transformation with NF-kappaB. Activation of downstream genes leads to cell proliferation, inhibition of apoptosis, angiogenesis, inflammation, invasion, and metastasis

  3. NF-kappaB in Lung Tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Zhenjian [Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, New York University School of Medicine, 462 First Avenue, NBV 7N24, New York, NY 10016 (United States); Tchou-Wong, Kam-Meng; Rom, William N., E-mail: william.rom@nyumc.org [Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, New York University School of Medicine, 462 First Avenue, NBV 7N24, New York, NY 10016 (United States); Department of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987 (United States)

    2011-12-14

    The development of lung cancer in humans can be divided into three steps initiation, promotion and progression. This process is driven by alterations in related signal transduction pathways. These pathways signal the aberrant activation of NF-kappaB, a transcription factor that regulates the expression of genes important for lung tumorigenesis. Our current knowledge about the role of the NF-kappaB signaling pathway in the development of lung cancer has been bolstered by animal models demonstrating the connection between K-ras and tobacco induced lung transformation with NF-kappaB. Activation of downstream genes leads to cell proliferation, inhibition of apoptosis, angiogenesis, inflammation, invasion, and metastasis.

  4. [NF-κB signaling pathways and the future perspectives of bone disease therapy using selective inhibitors of NF-κB].

    Science.gov (United States)

    Jimi, Eijiro; Fukushima, Hidefumi

    2016-02-01

    The transcriptional factor nuclear factor κB(NF-κB)regulates the expression of a wide variety of genes that are involved in immune and inflammatory responses, proliferation, and tumorigenesis. NF-κB consists of five members, such as p65(RelA), RelB, c-Rel, p50/p105(NF-κB1), and p52/p100(NF-κB2). There are two distinct NF-κB activation pathways, termed the classical and alternative NF-κB signaling pathways. Since mice lacking both p50 and p52 subunits developed typical osteopetrosis, due to total lack of osteoclasts, NF-κB is also important osteoclast differentiation. A selective NF-κB inhibitor blocked receptor activator of NF-κB ligand(RANKL)-induced osteoclastogenesis both in vitro and in vivo. Recent findings have shown that inactivation of NF-κB enhances osteoblast differentiation in vitro and bone formation in vivo. NF-κB is constitutively activated in many cancers including oral squamous cell carcinoma(OSCC), and is involved in the invasive characteristics of OSCC. A selective NF-κB inhibitor also prevented jaw bone destruction by OSCC by reduced osteoclast numbers in animal model. Thus the inhibition of NF-κB might useful for the treatment of bone diseases, such as arthritis, osteoporosis, periodontitis, and bone invasion by OSCC by inhibiting bone resorption and by stimulating bone formation.

  5. NF-κB and p53 Are the Dominant Apoptosis-inducing Transcription Factors Elicited by the HIV-1 Envelope

    OpenAIRE

    Perfettini, Jean-Luc; Roumier, Thomas; Castedo, Maria; Larochette, Nathanael; Boya, Patricia; Raynal, Brigitte; Lazar, Vladimir; Ciccosanti, Fabiola; Nardacci, Roberta; Penninger, Josef; Piacentini, Mauro; Kroemer, Guido

    2004-01-01

    The coculture of cells expressing the HIV-1 envelope glycoprotein complex (Env) with cells expressing CD4 results into cell fusion, deregulated mitosis, and subsequent cell death. Here, we show that NF-κB, p53, and AP1 are activated in Env-elicited apoptosis. The nuclear factor κB (NF-κB) super repressor had an antimitotic and antiapoptotic effect and prevented the Env-elicited phosphorylation of p53 on serine 15 and 46, as well as the activation of AP1. Transfection with dominant-negative p5...

  6. Insights into iron and nuclear factor-kappa B (NF-kappaB) involvement in chronic inflammatory processes in peritoneal endometriosis.

    Science.gov (United States)

    Defrère, Sylvie; González-Ramos, Reinaldo; Lousse, Jean-Christophe; Colette, Sébastien; Donnez, Olivier; Donnez, Jacques; Van Langendonckt, Anne

    2011-08-01

    Endometriosis is a chronic pelvic inflammatory process. Local inflammation is known to play a role in pain and infertility associated with the disease, and may be extensively involved in molecular and cellular processes leading to endometriosis development. In this review, we focus on two inflammatory mediators clearly implicated in the pathogenesis of endometriosis, iron and NF-kappaB, and their potential association. Iron is essential for all living organisms, but excess iron results in toxicity and is linked to pathological disorders. In endometriosis patients, iron overload has been demonstrated in the different compartments of the peritoneal cavity (peritoneal fluid, endometriotic lesions, peritoneum and macrophages). This iron overload affects numerous mechanisms involved in endometriosis development. Moreover, iron can generate free radical species able to react with a wide range of cellular constituents, inducing cellular damage. Overproduction of reactive oxygen species also impairs cellular function by altering gene expression via regulation of redox-sensitive transcription factors such as NF-kappaB, which is clearly implicated in endometriosis. Indeed, NF-kappaB is activated in endometriotic lesions and peritoneal macrophages of endometriosis patients, which stimulates synthesis of proinflammatory cytokines, generating a positive feedback loop in the NF-kappaB pathway. NF-kappaB-mediated gene transcription promotes a variety of processes, including endometriotic lesion establishment, maintenance and development. In conclusion, iron and NF-kappaB appear to be linked and both are clearly involved in endometriosis development, making these pathways an attractive target for future treatment and prevention of this disease.

  7. ANKRD1 modulates inflammatory responses in C2C12 myoblasts through feedback inhibition of NF-κB signaling activity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xin-Hua [National Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, NY 10468 (United States); Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Bauman, William A. [National Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, NY 10468 (United States); Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Cardozo, Christopher, E-mail: chris.cardozo@va.gov [National Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peter VA Medical Center, Bronx, NY 10468 (United States); Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States)

    2015-08-14

    Transcription factors of the nuclear factor-kappa B (NF-κB) family play a pivotal role in inflammation, immunity and cell survival responses. Recent studies revealed that NF-κB also regulates the processes of muscle atrophy. NF-κB activity is regulated by various factors, including ankyrin repeat domain 2 (AnkrD2), which belongs to the muscle ankyrin repeat protein family. Another member of this family, AnkrD1 is also a transcriptional effector. The expression levels of AnkrD1 are highly upregulated in denervated skeletal muscle, suggesting an involvement of AnkrD1 in NF-κB mediated cellular responses to paralysis. However, the molecular mechanism underlying the interactive role of AnkrD1 in NF-κB mediated cellular responses is not well understood. In the current study, we examined the effect of AnkrD1 on NF-κB activity and determined the interactions between AnkrD1 expression and NF-κB signaling induced by TNFα in differentiating C2C12 myoblasts. TNFα upregulated AnkrD1 mRNA and protein levels. AnkrD1-siRNA significantly increased TNFα-induced transcriptional activation of NF-κB, whereas overexpression of AnkrD1 inhibited TNFα-induced NF-κB activity. Co-immunoprecipitation studies demonstrated that AnkrD1 was able to bind p50 subunit of NF-κB and vice versa. Finally, CHIP assays revealed that AnkrD1 bound chromatin at a NF-κB binding site in the AnrkD2 promoter and required NF-κB to do so. These results provide evidence of signaling integration between AnkrD1 and NF-κB pathways, and suggest a novel anti-inflammatory role of AnkrD1 through feedback inhibition of NF-κB transcriptional activity by which AnkrD1 modulates the balance between physiological and pathological inflammatory responses in skeletal muscle. - Highlights: • AnkrD1 is upregulated by TNFα and represses NF-κB-induced transcriptional activity. • AnkrD1 binds to p50 subunit of NF-κB and is recruited to NF-κB bound to chromatin. • AnkrD1 mediates a feed-back inhibitory loop

  8. Insulin receptor substrate-3, interacting with Bcl-3, enhances p50 NF-{kappa}B activity

    Energy Technology Data Exchange (ETDEWEB)

    Kabuta, Tomohiro [Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657 (Japan); Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502 (Japan); Hakuno, Fumihiko; Cho, Yoshitake; Yamanaka, Daisuke; Chida, Kazuhiro [Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657 (Japan); Asano, Tomoichiro [Graduate School of Biomedical Science, Hiroshima University, Hiroshima 734-8551 (Japan); Wada, Keiji [Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502 (Japan); Takahashi, Shin-Ichiro, E-mail: atkshin@mail.ecc.u-tokyo.ac.jp [Departments of Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657 (Japan)

    2010-04-09

    The insulin receptor substrate (IRS) proteins are major substrates of both insulin receptor and insulin-like growth factor (IGF)-I receptor tyrosine kinases. Previously, we reported that IRS-3 is localized to both cytosol and nucleus, and possesses transcriptional activity. In the present study, we identified Bcl-3 as a novel binding protein to IRS-3. Bcl-3 is a nuclear protein, which forms a complex with the homodimer of p50 NF-{kappa}B, leading to enhancement of transcription through p50 NF-{kappa}B. We found that Bcl-3 interacts with the pleckstrin homology domain and the phosphotyrosine binding domain of IRS-3, and that IRS-3 interacts with the ankyrin repeat domain of Bcl-3. In addition, IRS-3 augmented the binding activity of p50 to the NF-{kappa}B DNA binding site, as well as the tumor necrosis factor (TNF)-{alpha}-induced transcriptional activity of NF-{kappa}B. Lastly, IRS-3 enhanced NF-{kappa}B-dependent anti-apoptotic gene induction and consequently inhibited TNF-{alpha}-induced cell death. This series of results proposes a novel function for IRS-3 as a transcriptional regulator in TNF-{alpha} signaling, distinct from its function as a substrate of insulin/IGF receptor kinases.

  9. Late-phase synthesis of I��B�� insulates the TLR4-activated canonical NF-��B pathway from noncanonical NF-��B signaling in macrophages

    OpenAIRE

    Chatterjee, Budhaditya; Banoth, Balaji; Mukherjee, Tapas; Taye, Nandaraj; Vijayaragavan, Bharath; Chattopadhyay, Samit; Gomes, James; Basak, Soumen

    2016-01-01

    The nuclear factor ��B (NF-��B) transcription factors coordinate the inflammatory immune response during microbial infection. Pathogenic substances engage canonical NF-��B signaling through the heterodimer RelA:p50, which is subjected to rapid negative feedback by inhibitor of ��B�� (I��B��). The noncanonical NF-��B pathway is required for the differentiation of immune cells; however, crosstalk between both pathways can occur. Concomitantly activated noncanonical signaling generates p52 from ...

  10. OsNF-YC2 and OsNF-YC4 proteins inhibit flowering under long-day conditions in rice

    KAUST Repository

    Kim, SoonKap

    2015-11-05

    OsNF-YC2 and OsNF-YC4 proteins regulate the photoperiodic flowering response through the modulation of three flowering-time genes ( Ehd1, Hd3a , and RFT1 ) in rice. Plant NUCLEAR FACTOR Y (NF-Y) transcription factors control numerous developmental processes by forming heterotrimeric complexes, but little is known about their roles in flowering in rice. In this study, it is shown that some subunits of OsNF-YB and OsNF-YC interact with each other, and among them, OsNF-YC2 and OsNF-YC4 proteins regulate the photoperiodic flowering response of rice. Protein interaction studies showed that the physical interactions occurred between the three OsNF-YC proteins (OsNF-YC2, OsNF-YC4 and OsNF-YC6) and three OsNF-YB proteins (OsNF-YB8, OsNF-YB10 and OsNF-YB11). Repression and overexpression of the OsNF-YC2 and OsNF-YC4 genes revealed that they act as inhibitors of flowering only under long-day (LD) conditions. Overexpression of OsNF-YC6, however, promoted flowering only under LD conditions, suggesting it could function as a flowering promoter. These phenotypes correlated with the changes in the expression of three rice flowering-time genes [Early heading date 1 (Ehd1), Heading date 3a (Hd3a) and RICE FLOWERING LOCUS T1 (RFT1)]. The diurnal and tissue-specific expression patterns of the subsets of OsNF-YB and OsNF-YC genes were similar to those of CCT domain encoding genes such as OsCO3, Heading date 1 (Hd1) and Ghd7. We propose that OsNF-YC2 and OsNF-YC4 proteins regulate the photoperiodic flowering response by interacting directly with OsNF-YB8, OsNF-YB10 or OsNF-YB11 proteins in rice.

  11. Targeting of NF-κB to Dendritic Spines Is Required for Synaptic Signaling and Spine Development.

    Science.gov (United States)

    Dresselhaus, Erica C; Boersma, Matthew C H; Meffert, Mollie K

    2018-04-25

    Long-term forms of brain plasticity share a requirement for changes in gene expression induced by neuronal activity. Mechanisms that determine how the distinct and overlapping functions of multiple activity-responsive transcription factors, including nuclear factor κB (NF-κB), give rise to stimulus-appropriate neuronal responses remain unclear. We report that the p65/RelA subunit of NF-κB confers subcellular enrichment at neuronal dendritic spines and engineer a p65 mutant that lacks spine enrichment (p65ΔSE) but retains inherent transcriptional activity equivalent to wild-type p65. Wild-type p65 or p65ΔSE both rescue NF-κB-dependent gene expression in p65-deficient murine hippocampal neurons responding to diffuse (PMA/ionomycin) stimulation. In contrast, neurons lacking spine-enriched NF-κB are selectively impaired in NF-κB-dependent gene expression induced by elevated excitatory synaptic stimulation (bicuculline or glycine). We used the setting of excitatory synaptic activity during development that produces NF-κB-dependent growth of dendritic spines to test physiological function of spine-enriched NF-κB in an activity-dependent response. Expression of wild-type p65, but not p65ΔSE, is capable of rescuing spine density to normal levels in p65-deficient pyramidal neurons. Collectively, these data reveal that spatial localization in dendritic spines contributes unique capacities to the NF-κB transcription factor in synaptic activity-dependent responses. SIGNIFICANCE STATEMENT Extensive research has established a model in which the regulation of neuronal gene expression enables enduring forms of plasticity and learning. However, mechanisms imparting stimulus specificity to gene regulation, ensuring biologically appropriate responses, remain incompletely understood. NF-κB is a potent transcription factor with evolutionarily conserved functions in learning and the growth of excitatory synaptic contacts. Neuronal NF-κB is localized in both synapse and

  12. C26 cancer-induced muscle wasting is IKKβ-dependent and NF-kappaB-independent.

    Directory of Open Access Journals (Sweden)

    Evangeline W Cornwell

    Full Text Available Existing data suggest that NF-kappaB signaling is a key regulator of cancer-induced skeletal muscle wasting. However, identification of the components of this signaling pathway and of the NF-κB transcription factors that regulate wasting is far from complete. In muscles of C26 tumor bearing mice, overexpression of dominant negative (d.n. IKKβ blocked muscle wasting by 69% and the IκBα-super repressor blocked wasting by 41%. In contrast, overexpression of d.n. IKKα or d.n. NIK did not block C26-induced wasting. Surprisingly, overexpression of d.n. p65 or d.n. c-Rel did not significantly affect muscle wasting. Genome-wide mRNA expression arrays showed upregulation of many genes previously implicated in muscle atrophy. To test if these upregulated genes were direct targets of NF-κB transcription factors, we compared genome-wide p65 binding to DNA in control and cachectic muscle using ChIP-sequencing. Bioinformatic analysis of ChIP-sequencing data from control and C26 muscles showed very little p65 binding to genes in cachexia and little to suggest that upregulated p65 binding influences the gene expression associated with muscle based cachexia. The p65 ChIP-seq data are consistent with our finding of no significant change in protein binding to an NF-κB oligonucleotide in a gel shift assay, no activation of a NF-κB-dependent reporter, and no effect of d.n.p65 overexpression in muscles of tumor bearing mice. Taken together, these data support the idea that although inhibition of IκBα, and particularly IKKβ, blocks cancer-induced wasting, the alternative NF-κB signaling pathway is not required. In addition, the downstream NF-κB transcription factors, p65 and c-Rel do not appear to regulate the transcriptional changes induced by the C26 tumor. These data are consistent with the growing body of literature showing that there are NF-κB-independent substrates of IKKβ and IκBα that regulate physiological processes.

  13. Functional conservation of rice OsNF-YB/YC and Arabidopsis AtNF-YB/YC proteins in the regulation of flowering time

    KAUST Repository

    Hwang, Yoon-Hyung; Kim, SoonKap; Lee, Keh Chien; Chung, Young Soo; Lee, Jeong Hwan; Kim, Jeong-Kook

    2016-01-01

    Plant NUCLEAR FACTOR Y (NF-Y) transcription factors play important roles in plant development and abiotic stress. In Arabidopsis thaliana, two NF-YB (AtNF-YB2 and AtNF-YB3) and five NF-YC (AtNF-YC1, AtNF-YC2, AtNF-YC3, AtNF-YC4, and AtNF-YC9) genes regulate photoperiodic flowering by interacting with other AtNF-Y subunit proteins. Three rice NF-YB (OsNF-YB8, OsNF-YB10, and OsNF-YB11) and five rice OsNF-YC (OsNF-YC1, OsNF-YC2, OsNF-YC4, OsNF-YC6, and OsNF-YC7) genes are clustered with two AtNF-YB and five AtNF-YC genes, respectively. To investigate the functional conservation of these NF-YB and NF-YC genes in rice and Arabidopsis, we analyzed the flowering phenotypes of transgenic plants overexpressing the respective OsNF-YB and OsNF-YC genes in Arabidopsis mutants. Overexpression of OsNF-YB8/10/11 and OsNF-YC2 complemented the late flowering phenotype of Arabidopsis nf-yb2 nf-yb3 and nf-yc3 nf-yc4 nf-yc9 mutants, respectively. The rescued phenotype of 35S::OsNF-YC2 nf-yc3 nf-yc4 nf-yc9 plants was attributed to the upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). In vitro and in planta protein–protein analyses revealed that OsNF-YB8/10/11 and OsNF-YC1/2/4/6/7 interact with AtNF-YC3/4/9 and AtNF-YB2/3, respectively. Our data indicate that some OsNF-YB and OsNF-YC genes are functional equivalents of AtNF-YB2/3 and AtNF-YC3/4/9 genes, respectively, and suggest functional conservation of Arabidopsis and rice NF-Y genes in the control of flowering time.

  14. Functional conservation of rice OsNF-YB/YC and Arabidopsis AtNF-YB/YC proteins in the regulation of flowering time

    KAUST Repository

    Hwang, Yoon-Hyung

    2016-01-11

    Plant NUCLEAR FACTOR Y (NF-Y) transcription factors play important roles in plant development and abiotic stress. In Arabidopsis thaliana, two NF-YB (AtNF-YB2 and AtNF-YB3) and five NF-YC (AtNF-YC1, AtNF-YC2, AtNF-YC3, AtNF-YC4, and AtNF-YC9) genes regulate photoperiodic flowering by interacting with other AtNF-Y subunit proteins. Three rice NF-YB (OsNF-YB8, OsNF-YB10, and OsNF-YB11) and five rice OsNF-YC (OsNF-YC1, OsNF-YC2, OsNF-YC4, OsNF-YC6, and OsNF-YC7) genes are clustered with two AtNF-YB and five AtNF-YC genes, respectively. To investigate the functional conservation of these NF-YB and NF-YC genes in rice and Arabidopsis, we analyzed the flowering phenotypes of transgenic plants overexpressing the respective OsNF-YB and OsNF-YC genes in Arabidopsis mutants. Overexpression of OsNF-YB8/10/11 and OsNF-YC2 complemented the late flowering phenotype of Arabidopsis nf-yb2 nf-yb3 and nf-yc3 nf-yc4 nf-yc9 mutants, respectively. The rescued phenotype of 35S::OsNF-YC2 nf-yc3 nf-yc4 nf-yc9 plants was attributed to the upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). In vitro and in planta protein–protein analyses revealed that OsNF-YB8/10/11 and OsNF-YC1/2/4/6/7 interact with AtNF-YC3/4/9 and AtNF-YB2/3, respectively. Our data indicate that some OsNF-YB and OsNF-YC genes are functional equivalents of AtNF-YB2/3 and AtNF-YC3/4/9 genes, respectively, and suggest functional conservation of Arabidopsis and rice NF-Y genes in the control of flowering time.

  15. The Arabidopsis NF-YA3 and NF-YA8 genes are functionally redundant and are required in early embryogenesis.

    Directory of Open Access Journals (Sweden)

    Monica Fornari

    Full Text Available Nuclear factor Y (NF-Y is a trimeric transcription factor composed of three distinct subunits called NF-YA, NF-YB and NF-YC. In Arabidopsis thaliana, NF-Y subunits are known to play roles in many processes, such as gametogenesis, embryogenesis, seed development, drought resistance, ABA signaling, flowering time, primary root elongation, Endoplasmic Reticulum (ER stress response and blue light responses. Here, we report that the closely related NF-YA3 and NF-YA8 genes control early embryogenesis. Detailed GUS and in situ analyses showed that NF-YA3 and NF-YA8 are expressed in vegetative and reproductive tissues with the highest expression being during embryo development from the globular to the torpedo embryo stage. Plants from the nf-ya3 and nf-ya8 single mutants do not display any obvious phenotypic alteration, whereas nf-ya3 nf-ya8 double mutants are embryo lethal. Morphological analyses showed that the nf-ya3 nf-ya8 embryos fail to undergo to the heart stage and develop into abnormal globular embryos with both proembryo and suspensor characterized by a disordered cell cluster with an irregular shape, suggesting defects in embryo development. The suppression of both NF-YA3 and NF-YA8 gene expression by RNAi experiments resulted in defective embryos that phenocopied the nf-ya3 nf-ya8 double mutants, whereas complementation experiments partially rescued the abnormal globular nf-ya3 nf-ya8 embryos, confirming that NF-YA3 and NF-YA8 are required in early embryogenesis. Finally, the lack of GFP expression of the auxin responsive DR5rev::GFP marker line in double mutant embryos suggested that mutations in both NF-YA3 and NF-YA8 affect auxin response in early developing embryos. Our findings indicate that NF-YA3 and NF-YA8 are functionally redundant genes required in early embryogenesis of Arabidopsis thaliana.

  16. NF-Y recruits both transcription activator and repressor to modulate tissue- and developmental stage-specific expression of human γ-globin gene.

    Directory of Open Access Journals (Sweden)

    Xingguo Zhu

    Full Text Available The human embryonic, fetal and adult β-like globin genes provide a paradigm for tissue- and developmental stage-specific gene regulation. The fetal γ-globin gene is expressed in fetal erythroid cells but is repressed in adult erythroid cells. The molecular mechanism underlying this transcriptional switch during erythroid development is not completely understood. Here, we used a combination of in vitro and in vivo assays to dissect the molecular assemblies of the active and the repressed proximal γ-globin promoter complexes in K562 human erythroleukemia cell line and primary human fetal and adult erythroid cells. We found that the proximal γ-globin promoter complex is assembled by a developmentally regulated, general transcription activator NF-Y bound strongly at the tandem CCAAT motifs near the TATA box. NF-Y recruits to neighboring DNA motifs the developmentally regulated, erythroid transcription activator GATA-2 and general repressor BCL11A, which in turn recruit erythroid repressor GATA-1 and general repressor COUP-TFII to form respectively the NF-Y/GATA-2 transcription activator hub and the BCL11A/COUP-TFII/GATA-1 transcription repressor hub. Both the activator and the repressor hubs are present in both the active and the repressed γ-globin promoter complexes in fetal and adult erythroid cells. Through changes in their levels and respective interactions with the co-activators and co-repressors during erythroid development, the activator and the repressor hubs modulate erythroid- and developmental stage-specific transcription of γ-globin gene.

  17. THE ROLE OF NF-κB IN NEURONAL PLASTICITY AND NEURODEGENERATIVE DISEASES

    OpenAIRE

    Yağmur, Elif Nuran; Yıldız, Nazım; Adıgüzel, Serkan; Femir, Banu; Şenyer, Seray; Şen, Melis; Tüzün, Erdem; Küçükali, Cem İsmail

    2018-01-01

    NF-κB is a transcription factor emerged by the end of 20th century. At the beginning, NF-κB wasfound to be present in immune cells but following studies showed its presence in almost all cells inan organism. NF-κB takes part in the activation of almost 500 genes and have roles in mechanismsincluding immune response, cell cycle, cell survival, cell proliferation and development, as well asplasticity and memory formation. Long-term potentiation (LTP) of NF-κB in the central nervoussystem (CNS) ...

  18. Induction of Epstein-Barr Virus Oncoprotein LMP1 by Transcription Factors AP-2 and Early B Cell Factor

    Science.gov (United States)

    Noda, Chieko; Narita, Yohei; Watanabe, Takahiro; Yoshida, Masahiro; Ashio, Keiji; Sato, Yoshitaka; Goshima, Fumi; Kanda, Teru; Yoshiyama, Hironori; Tsurumi, Tatsuya; Kimura, Hiroshi

    2016-01-01

    ABSTRACT Latent membrane protein 1 (LMP1) is a major oncogene essential for primary B cell transformation by Epstein-Barr virus (EBV). Previous studies suggested that some transcription factors, such as PU.1, RBP-Jκ, NF-κB, and STAT, are involved in this expression, but the underlying mechanism is unclear. Here, we identified binding sites for PAX5, AP-2, and EBF in the proximal LMP1 promoter (ED-L1p). We first confirmed the significance of PU.1 and POU domain transcription factor binding for activation of the promoter in latency III. We then focused on the transcription factors AP-2 and early B cell factor (EBF). Interestingly, among the three AP-2-binding sites in the LMP1 promoter, two motifs were also bound by EBF. Overexpression, knockdown, and mutagenesis in the context of the viral genome indicated that AP-2 plays an important role in LMP1 expression in latency II in epithelial cells. In latency III B cells, on the other hand, the B cell-specific transcription factor EBF binds to the ED-L1p and activates LMP1 transcription from the promoter. IMPORTANCE Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) is crucial for B cell transformation and oncogenesis of other EBV-related malignancies, such as nasopharyngeal carcinoma and T/NK lymphoma. Its expression is largely dependent on the cell type or condition, and some transcription factors have been implicated in its regulation. However, these previous reports evaluated the significance of specific factors mostly by reporter assay. In this study, we prepared point-mutated EBV at the binding sites of such transcription factors and confirmed the importance of AP-2, EBF, PU.1, and POU domain factors. Our results will provide insight into the transcriptional regulation of the major oncogene LMP1. PMID:26819314

  19. Estrogen receptor alpha and nuclear factor Y coordinately regulate the transcription of the SUMO-conjugating UBC9 gene in MCF-7 breast cancer cells.

    Science.gov (United States)

    Ying, Shibo; Dünnebier, Thomas; Si, Jing; Hamann, Ute

    2013-01-01

    UBC9 encodes a protein that conjugates small ubiquitin-related modifier (SUMO) to target proteins thereby changing their functions. Recently, it was noted that UBC9 expression and activity play a role in breast tumorigenesis and response to anticancer drugs. However, the underlying mechanism is poorly understood. To investigate the transcriptional regulation of the UBC9 gene, we identified and characterized its promoter and cis-elements. Promoter activity was tested using luciferase reporter assays. The binding of transcription factors to the promoter was detected by chromatin immunoprecipitation (ChIP), and their functional role was confirmed by siRNA knockdown. UBC9 mRNA and protein levels were measured by quantitative reverse transcription PCR and Western blot analysis, respectively. An increased expression of UBC9 mRNA and protein was found in MCF-7 breast cancer cells treated with 17β-estradiol (E2). Analysis of various deletion mutants revealed a 137 bp fragment upstream of the transcription initiation site to be sufficient for reporter gene transcription. Mutations of putative estrogen receptor α (ER-α) (one imperfect estrogen response element, ERE) and/or nuclear factor Y (NF-Y) binding sites (two CCAAT boxes) markedly reduced promoter activity. Similar results were obtained in ER-negative MDA-MB-231 cells except that the ERE mutation did not affect promoter activity. Additionally, promoter activity was stimulated upon E2 treatment and overexpression of ER-α or NF-YA in MCF-7 cells. ChIP confirmed direct binding of both transcription factors to the UBC9 promoter in vivo. Furthermore, UBC9 expression was diminished by ER-α and NF-Y siRNAs on the mRNA and protein levels. In conclusion, we identified the proximal UBC9 promoter and provided evidence that ER-α and NF-Y regulate UBC9 expression on the transcriptional level in response to E2 in MCF-7 cells. These findings may contribute to a better understanding of the regulation of UBC9 in ER

  20. CREB, NF-Y and MEIS1 conserved binding sites are essential to balance Myostatin promoter/enhancer activity during early myogenesis.

    Science.gov (United States)

    Grade, Carla Vermeulen Carvalho; Mantovani, Carolina Stefano; Fontoura, Marina Alves; Yusuf, Faisal; Brand-Saberi, Beate; Alvares, Lúcia Elvira

    2017-10-01

    Myostatin (MSTN) is a strong inhibitor of skeletal muscle growth in human and other vertebrates. Its transcription is controlled by a proximal promoter/enhancer (Mstn P/E) containing a TATA box besides CREB, NF-Y, MEIS1 and FXR transcription factor binding sites (TFBSs), which are conserved throughout evolution. The aim of this work was to investigate the role of these TFBSs on Mstn P/E activity and evaluate the potential of their putative ligands as Mstn trans regulators. Mstn P/E mutant constructs were used to establish the role of conserved TFBSs using dual-luciferase assays. Expression analyses were performed by RT-PCR and in situ hybridization in C2C12 myoblasts and E10.5 mouse embryos, respectively. Our results revealed that CREB, NF-Y and MEIS1 sites are required to balance Mstn P/E activity, keeping Mstn transcription within basal levels during myoblast proliferation. Furthermore, our data showed that NF-Y site is essential, although not sufficient, to mediate Mstn P/E transcriptional activity. In turn, CREB and MEIS1 binding sites seem to depend on the presence of NF-Y site to induce Mstn P/E. FXR appears not to confer any effect on Mstn P/E activity, except in the absence of all other conserved TFBS. Accordingly, expression studies pointed to CREB, NF-Y and MEIS1 but not to FXR factors as possible regulators of Mstn transcription in the myogenic context. Altogether, our findings indicated that CREB, NF-Y and MEIS1 conserved sites are essential to control basal Mstn transcription during early myogenesis, possibly by interacting with these or other related factors.

  1. Genistein inhibits phorbol ester-induced NF-κB transcriptional activity and COX-2 expression by blocking the phosphorylation of p65/RelA in human mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Myung-Hoon; Kim, Do-Hee [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Na, Hye-Kyung [Department of Food and Nutrition, Sungshin Women' s University, Seoul (Korea, Republic of); Kim, Jung-Hwan; Kim, Ha-Na [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Haegeman, Guy [LEGEST, University of Gent (Belgium); Surh, Young-Joon, E-mail: surh@snu.ac.kr [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University, Seoul (Korea, Republic of)

    2014-10-15

    Genistein, an isoflavone present in soy products, has chemopreventive effects on mammary carcinogenesis. In the present study, we have investigated the effects of genistein on phorbol ester-induced expression of cyclooxygenase-2 (COX-2) that plays an important role in the pathophysiology of inflammation-associated carcinogenesis. Pretreatment of cultured human breast epithelial (MCF10A) cells with genistein reduced COX-2 expression induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). There are multiple lines of evidence supporting that the induction of COX-2 is regulated by the eukaryotic transcription factor NF-κB. Genistein failed to inhibit TPA-induced nuclear translocation and DNA binding of NF-κB as well as degradation of IκB. However, genistein abrogated the TPA-induced transcriptional activity of NF-κB as determined by the luciferase reporter gene assay. Genistein inhibited phosphorylation of the p65 subunit of NF-κB and its interaction with cAMP regulatory element-binding protein-binding protein (CBP)/p300 and TATA-binding protein (TBP). TPA-induced NF-κB phosphorylation was abolished by pharmacological inhibition of extracellular signal-regulated kinase (ERK). Likewise, pharmacologic inhibition or dominant negative mutation of ERK suppressed phosphorylation of p65. The above findings, taken together, suggest that genistein inhibits TPA-induced COX-2 expression in MCF10A cells by blocking ERK-mediated phosphorylation of p65 and its subsequent interaction with CBP and TBP.

  2. Effect of particle size on hydroxyapatite crystal-induced tumor necrosis factor alpha secretion by macrophages.

    Science.gov (United States)

    Nadra, Imad; Boccaccini, Aldo R; Philippidis, Pandelis; Whelan, Linda C; McCarthy, Geraldine M; Haskard, Dorian O; Landis, R Clive

    2008-01-01

    Macrophages may promote a vicious cycle of inflammation and calcification in the vessel wall by ingesting neointimal calcific deposits (predominantly hydroxyapatite) and secreting tumor necrosis factor (TNF)alpha, itself a vascular calcifying agent. Here we have investigated whether particle size affects the proinflammatory potential of hydroxyapatite crystals in vitro and whether the nuclear factor (NF)-kappaB pathway plays a role in the macrophage TNFalpha response. The particle size and nano-topography of nine different crystal preparations was analyzed by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and gas sorbtion analysis. Macrophage TNFalpha secretion was inversely related to hydroxyapatite particle size (P=0.011, Spearman rank correlation test) and surface pore size (P=0.014). A necessary role for the NF-kappaB pathway was demonstrated by time-dependent I kappaB alpha degradation and sensitivity to inhibitors of I kappaB alpha degradation. To test whether smaller particles were intrinsically more bioactive, their mitogenic activity on fibroblast proliferation was examined. This showed close correlation between TNFalpha secretion and crystal-induced fibroblast proliferation (P=0.007). In conclusion, the ability of hydroxyapatite crystals to stimulate macrophage TNFalpha secretion depends on NF-kappaB activation and is inversely related to particle and pore size, with crystals of 1-2 microm diameter and pore size of 10-50 A the most bioactive. Microscopic calcific deposits in early stages of atherosclerosis may therefore pose a greater inflammatory risk to the plaque than macroscopically or radiologically visible deposits in more advanced lesions.

  3. Hydrogen peroxide sensing, signaling and regulation of transcription factors

    Directory of Open Access Journals (Sweden)

    H. Susana Marinho

    2014-01-01

    Full Text Available The regulatory mechanisms by which hydrogen peroxide (H2O2 modulates the activity of transcription factors in bacteria (OxyR and PerR, lower eukaryotes (Yap1, Maf1, Hsf1 and Msn2/4 and mammalian cells (AP-1, NRF2, CREB, HSF1, HIF-1, TP53, NF-κB, NOTCH, SP1 and SCREB-1 are reviewed. The complexity of regulatory networks increases throughout the phylogenetic tree, reaching a high level of complexity in mammalians. Multiple H2O2 sensors and pathways are triggered converging in the regulation of transcription factors at several levels: (1 synthesis of the transcription factor by upregulating transcription or increasing both mRNA stability and translation; (ii stability of the transcription factor by decreasing its association with the ubiquitin E3 ligase complex or by inhibiting this complex; (iii cytoplasm–nuclear traffic by exposing/masking nuclear localization signals, or by releasing the transcription factor from partners or from membrane anchors; and (iv DNA binding and nuclear transactivation by modulating transcription factor affinity towards DNA, co-activators or repressors, and by targeting specific regions of chromatin to activate individual genes. We also discuss how H2O2 biological specificity results from diverse thiol protein sensors, with different reactivity of their sulfhydryl groups towards H2O2, being activated by different concentrations and times of exposure to H2O2. The specific regulation of local H2O2 concentrations is also crucial and results from H2O2 localized production and removal controlled by signals. Finally, we formulate equations to extract from typical experiments quantitative data concerning H2O2 reactivity with sensor molecules. Rate constants of 140 M−1 s−1 and ≥1.3 × 103 M−1 s−1 were estimated, respectively, for the reaction of H2O2 with KEAP1 and with an unknown target that mediates NRF2 protein synthesis. In conclusion, the multitude of H2O2 targets and mechanisms provides an opportunity for

  4. Fisetin inhibits the generation of inflammatory mediators in interleukin-1β-induced human lung epithelial cells by suppressing the NF-κB and ERK1/2 pathways.

    Science.gov (United States)

    Peng, Hui-Ling; Huang, Wen-Chung; Cheng, Shu-Chen; Liou, Chian-Jiun

    2018-07-01

    Fisetin, a flavone that can be isolated from fruits and vegetables, has anti-tumor and anti-oxidative properties and ameliorates airway hyperresponsiveness in asthmatic mice. This study investigated whether fisetin can suppress the expression of inflammatory mediators and intercellular adhesion molecule 1 (ICAM-1) in A549 human lung epithelial cells that were stimulated with interleukin-1β (IL-1β) to induce inflammatory responses. A549 cells were treated with fisetin (3-30 μM) and then with IL-1β. Fisetin significantly inhibited COX-2 expression and reduced prostaglandin E 2 production, and it suppressed the levels of IL-8, CCL5, monocyte chemotactic protein 1, tumor necrosis factor α, and IL-6. Fisetin also significantly attenuated the expression of chemokine and inflammatory cytokine genes and decreased the expression of ICAM-1, which mediates THP-1 monocyte adhesion to inflammatory A549 cells. Fisetin decreased the translocation of nuclear transcription factor kappa-B (NF-κB) subunit p65 into the nucleus and inhibited the phosphorylation of proteins in the ERK1/2 pathway. Co-treatment of IL-1β-stimulated A549 cells with ERK1/2 inhibitors plus fisetin reduced ICAM-1 expression. Furthermore, fisetin significantly increased the effects of the protective antioxidant pathway by promoting the expression of nuclear factor erythroid-2-related factor-2 and heme oxygenase 1. Taken together, these data suggest that fisetin has anti-inflammatory effects and that it suppresses the expression of chemokines, inflammatory cytokines, and ICAM-1 by suppressing the NF-κB and ERK1/2 signaling pathways in IL-1β-stimulated human lung epithelial A549 cells. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Persistent activation of NF-kappaB related to IkappaB's degradation profiles during early chemical hepatocarcinogenesis

    Directory of Open Access Journals (Sweden)

    García-Román Rebeca

    2007-04-01

    Full Text Available Abstract Background To define the NF-kappaB activation in early stages of hepatocarcinogenesis and its IkappaB's degradation profiles in comparison to sole liver regeneration. Methods Western-blot and EMSA analyses were performed for the NF-kappaB activation. The transcriptional activity of NF-kappaB was determined by RT-PCR of the IkappaB-α mRNA. The IkappaB's degradation proteins were determined by Western-blot assay. Results We demonstrated the persistent activation of NF-kappaB during early stages of hepatocarcinogenesis, which reached maximal level 30 min after partial hepatectomy. The DNA binding and transcriptional activity of NF-kappaB, were sustained during early steps of hepatocarcinogenesis in comparison to only partial hepatectomy, which displayed a transitory NF-kappaB activation. In early stages of hepatocarconogenesis, the IkappaB-α degradation turned out to be acute and transitory, but the low levels of IkappaB-β persisted even 15 days after partial hepatectomy. Interestingly, IkappaB-β degradation is not induced after sole partial hepatectomy. Conclusion We propose that during liver regeneration, the transitory stimulation of the transcription factor response, assures blockade of NF-kappaB until recovery of the total mass of the liver and the persistent NF-kappaB activation in early hepatocarcinogenesis may be due to IkappaB-β and IkappaB-α degradation, mainly IkappaB-β degradation, which contributes to gene transcription related to proliferation required for neoplasic progression.

  6. Inhibition of NF-κB by a cell permeable form of IκBα induces apoptosis in eosinophils

    International Nuclear Information System (INIS)

    Fujihara, Satoko; Jaffray, Ellis; Farrow, Stuart N.; Rossi, Adriano G.; Haslett, Christopher; Hay, Ronald T.

    2005-01-01

    An 11 amino acid HIV-TAT peptide can deliver target proteins into a variety of cells in a receptor-independent manner. To generate a highly specific inhibitor of the transcription factor NF-κB, we have fused the TAT-peptide to a version of IκBα that is resistant to signal-induced degradation. TAT-IκBα(S32A, S36A) inhibited NF-κB-dependent transcription in HeLa and A549 cells by retaining NF-κB p65 in the cytoplasm. Introduction of TAT-IκBα(S32A, S36A) into human eosinophils inhibited the nuclear translocation of NF-κB and induced apoptosis. Thus, continuous NF-κB-dependent transcription is important for eosinophil survival. While eosinophils are normally refractive to standard methods of gene delivery, the ability of TAT fusion proteins to be taken up by these cells should enable a detailed molecular analysis of survival pathways in these cells

  7. Methylation-Dependent Activation of CDX1 through NF-κB

    Science.gov (United States)

    Rau, Tilman T.; Rogler, Anja; Frischauf, Myrjam; Jung, Andreas; Konturek, Peter C.; Dimmler, Arno; Faller, Gerhard; Sehnert, Bettina; El-Rifai, Wael; Hartmann, Arndt; Voll, Reinhard E.; Schneider-Stock, Regine

    2013-01-01

    The caudal homeobox factor 1 (CDX1) is an essential transcription factor for intestinal differentiation. Its aberrant expression in intestinal metaplasia of the upper gastrointestinal tract is a hallmark within the gastritis-metaplasia-carcinoma sequence. CDX1 expression is influenced by certain pathways, such as Wnt, Ras, or NF-κB signaling; however, these pathways alone cannot explain the transient expression of CDX1 in intestinal metaplasia or the molecular inactivation mechanism of its loss in cases of advanced gastric cancer. In this study, we investigated the epigenetic inactivation of CDX1 by promoter methylation, as well as the functional link of CDX1 promoter methylation to the inflammatory NF-κB signaling pathway. We identified methylation-dependent NF-κB binding to the CDX1 promoter and quantified it using competitive electrophoretic mobility shift assays and chromatin immunoprecipitation. A methylated CDX1 promoter was associated with closed chromatin structure, reduced NF-κB binding, and transcriptional silencing. Along the gastritis-metaplasia-carcinoma sequence, we observed a biphasic pattern of tumor necrosis factor-α (TNF-α) protein expression and an inverse biphasic pattern of CDX1 promoter methylation; both are highly consistent with CDX1 protein expression. The stages of hyper-, hypo-, and hyper-methylation patterns of the CDX1 promoter were inversely correlated with the NF-κB signaling activity along this sequence. In conclusion, these functionally interacting events drive CDX1 expression and contribute to intestinal metaplasia, epithelial dedifferentiation, and carcinogenesis in the human stomach. PMID:22749770

  8. NF45/ILF2 tissue expression, promoter analysis, and interleukin-2 transactivating function

    International Nuclear Information System (INIS)

    Zhao Guohua; Shi Lingfang; Qiu Daoming; Hu Hong; Kao, Peter N.

    2005-01-01

    NF45/ILF2 associates with NF90/ILF3 in the nucleus and regulates IL-2 gene transcription at the antigen receptor response element (ARRE)/NF-AT DNA target sequence (P.N. Kao, L. Chen, G. Brock, J. Ng, A.J. Smith, B. Corthesy, J. Biol. Chem. 269 (1994) 20691-20699). NF45 is widely expressed in normal tissues, especially testis, brain, and kidney, with a predominantly nuclear distribution. NF45 mRNA expression is increased in lymphoma and leukemia cell lines. The human and murine NF45 proteins differ only by substitution of valine by isoleucine at amino acid 142. Fluorescence in situ hybridization localized the human NF45 gene to chromosome 1q21.3, and mouse NF45 gene to chromosome 3F1. Promoter analysis of 2.5 kB of the murine NF45 gene reveals that significant activation is conferred by factors, possible including NF-Y, that bind to the CCAAT-box sequence. The function of human NF45 in regulating IL-2 gene expression was characterized in Jurkat T-cells stably transfected with plasmids directing expression of NF45 cDNA in sense or antisense orientations. NF45 sense expression increased IL-2 luciferase reporter gene activity 120-fold, and IL-2 protein expression 2-fold compared to control cells. NF45 is a highly conserved, regulated transcriptional activator, and one target gene is IL-2

  9. Leishmania major Infection Activates NF-κB and Interferon Regulatory Factors 1 and 8 in Human Dendritic Cells▿

    Science.gov (United States)

    Jayakumar, Asha; Donovan, Michael J.; Tripathi, Vinita; Ramalho-Ortigao, Marcelo; McDowell, Mary Ann

    2008-01-01

    The salient feature of dendritic cells (DC) is the initiation of appropriate adaptive immune responses by discriminating between pathogens. Using a prototypic model of intracellular infection, we previously showed that Leishmania major parasites prime human DC for efficient interleukin-12 (IL-12) secretion. L. major infection is associated with self-limiting cutaneous disease and powerful immunity. In stark contrast, the causative agent of visceral leishmaniasis, Leishmania donovani, does not prime human DC for IL-12 production. Here, we report that DC priming by L. major infection results in the early activation of NF-κB transcription factors and the up-regulation and nuclear translocation of interferon regulatory factor 1 (IRF-1) and IRF-8. The inhibition of NF-κB activation by the pretreatment of DC with caffeic acid phenethyl ester blocks L. major-induced IRF-1 and IRF-8 activation and IL-12 expression. We further demonstrate that IRF-1 and IRF-8 obtained from L. major-infected human DC specifically bind to their consensus binding sites on the IL-12p35 promoter, indicating that L. major infection either directly stimulates a signaling cascade or induces an autocrine pathway that activates IRF-1 and IRF-8, ultimately resulting in IL-12 transcription. PMID:18316378

  10. A requirement for NF-κB in developmental and plasticity-associated synaptogenesis

    Science.gov (United States)

    Boersma, Matthew C. H.; Dresselhaus, Erica C.; De Biase, Lindsay M.; Mihalas, Anca B.; Bergles, Dwight E.

    2011-01-01

    Structural plasticity of dendritic spines and synapses is a fundamental mechanism governing neuronal circuits and may form an enduring basis for information storage in the brain. We find that the p65 subunit of the NF-κB transcription factor, which is required for learning and memory, controls excitatory synapse and dendritic spine formation and morphology in murine hippocampal neurons. Endogenous NF-κB activity is elevated by excitatory transmission during periods of rapid spine and synapse development. During in-vitro synaptogenesis, NF-κB enhances dendritic spine and excitatory synapse density and loss of endogenous p65 decreases spine density and spine head volume. Cell-autonomous function of NF-κB within the postsynaptic neuron is sufficient to regulate the formation of both pre- and post-synaptic elements. During synapse development in-vivo, loss of NF-κB similarly reduces spine density and also diminishes the amplitude of synaptic responses. In contrast, after developmental synaptogenesis has plateaued, endogenous NF-κB activity is low and p65-deficiency no longer attenuates basal spine density. Instead, NF-κB in mature neurons is activated by stimuli that induce demand for new synapses, including estrogen and short-term bicuculline, and is essential for upregulating spine density in response to these stimuli. p65 is enriched in dendritic spines making local protein-protein interactions possible; however, the effects of NF-κB on spine density require transcription and the NF-κB-dependent regulation of PSD-95, a critical postsynaptic component. Collectively, our data define a distinct role for NF-κB in imparting transcriptional regulation required for the induction of changes to, but not maintenance of, excitatory synapse and spine density. PMID:21471377

  11. Turmeric (Curcuma longa) inhibits inflammatory nuclear factor (NF)-κB and NF-κB-regulated gene products and induces death receptors leading to suppressed proliferation, induced chemosensitization, and suppressed osteoclastogenesis.

    Science.gov (United States)

    Kim, Ji H; Gupta, Subash C; Park, Byoungduck; Yadav, Vivek R; Aggarwal, Bharat B

    2012-03-01

    The incidence of cancer is significantly lower in regions where turmeric is heavily consumed. Whether lower cancer incidence is due to turmeric was investigated by examining its effects on tumor cell proliferation, on pro-inflammatory transcription factors NF-κB and STAT3, and on associated gene products. Cell proliferation and cell cytotoxicity were measured by the MTT method, NF-κB activity by EMSA, protein expression by Western blot analysis, ROS generation by FACS analysis, and osteoclastogenesis by TRAP assay. Turmeric inhibited NF-κB activation and down-regulated NF-κB-regulated gene products linked to survival (Bcl-2, cFLIP, XIAP, and cIAP1), proliferation (cyclin D1 and c-Myc), and metastasis (CXCR4) of cancer cells. The spice suppressed the activation of STAT3, and induced the death receptors (DR)4 and DR5. Turmeric enhanced the production of ROS, and suppressed the growth of tumor cell lines. Furthermore, turmeric sensitized the tumor cells to chemotherapeutic agents capecitabine and taxol. Turmeric was found to be more potent than pure curcumin for cell growth inhibition. Turmeric also inhibited NF-κB activation induced by RANKL that correlated with the suppression of osteoclastogenesis. Our results indicate that turmeric can effectively block the proliferation of tumor cells through the suppression of NF-κB and STAT3 pathways. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Rosiglitazone inhibits chlorpyrifos-induced apoptosis via modulation of the oxidative stress and inflammatory response in SH-SY5Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Park, Jae Hyeon; Jang, Sea Jeong [Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2014-07-15

    Oxidative stress can lead to expression of inflammatory transcription factors, which are important regulatory elements in the induction of inflammatory responses. One of the transcription factors, nuclear transcription factor kappa-B (NF-κB) plays a significant role in the inflammation regulatory process. Inflammatory cell death has been implicated in neuronal cell death in some neurodegenerative disorders such as Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying apoptosis initiated by chlorpyrifos (CPF)-mediated oxidative stress. Based on the cytotoxic mechanism of CPF, we examined the neuroprotective effects of rosiglitazone (RGZ), a peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist, against CPF-induced neuronal cell death. The treatment of SH-SY5Y cells with CPF induced oxidative stress. In addition, CPF activated the p38, JNK and ERK mitogen-activated protein kinases (MAPKs), and induced increases in the inflammatory genes such as COX-2 and TNF-α. CPF also induced nuclear translocation of NF-κB and inhibitors of NF-κB abolished the CPF-induced COX-2 expression. Pretreatment with RGZ significantly reduced ROS generation and enhanced HO-1 expression in CPF-exposed cells. RGZ blocked the activation of both p38 and JNK signaling, while ERK activation was strengthened. RGZ also attenuated CPF-induced cell death through the reduction of NF-κB-mediated proinflammatory factors. Results from this study suggest that RGZ may exert an anti-apoptotic effect against CPF-induced cytotoxicity by attenuation of oxidative stress as well as inhibition of the inflammatory cascade via inactivation of signaling by p38 and JNK, and NF-κB. - Highlights: • CPF induces apoptotic cell death in SH-SY5Y cells • ROS involved in CPF-mediated apoptotic cell death • Inflammation involved in CPF-mediated apoptotic cell death • Rosiglitazone modulates ROS and inflammatory response in CPF-treated cells.

  13. Low-Dose Radiation Promotes Dendritic Cell Migration and IL-12 Production via the ATM/NF-KappaB Pathway.

    Science.gov (United States)

    Yu, Nan; Wang, Sinian; Song, Xiujun; Gao, Ling; Li, Wei; Yu, Huijie; Zhou, Chuanchuan; Wang, Zhenxia; Li, Fengsheng; Jiang, Qisheng

    2018-04-01

    For dendritic cells (DCs) to initiate an immune response, their ability to migrate and to produce interleukin-12 (IL-12) is crucial. It has been previously shown that low-dose radiation (LDR) promoted IL-12 production by DCs, resulting in increased DC activity that contributed to LDR hormesis in the immune system. However, the molecular mechanism of LDR-induced IL-12 production, as well as the effect of LDR on DC migration capacity require further elucidation. Using the JAWSII immortalized mouse dendritic cell line, we showed that in vitro X-ray irradiation (0.2 Gy) of DCs significantly increased DC migration and IL-12 production, and upregulated CCR7. The neutralizing antibody against CCR7 has been shown to abolish LDR-enhanced DC migration, demonstrating that CCR7 mediates LDR-promoting DC migration. We identified nuclear factor kappaB (NF-κB) as the central signaling pathway that mediated LDR-enhanced expression of IL-12 and CCR7 based on findings that 0.2 Gy X-ray irradiation activated NF-κB, showing increased nuclear p65 translocation and NF-κB DNA-binding activity, while an NF-κB inhibitor blocked LDR-enhanced expression of IL-12 and CCR7, as well as DC migration. Finally, we demonstrated that 0.2 Gy X-ray irradiation promoted ATM phosphorylation and reactive oxygen species generation; however, only the ATM inhibitor abolished the LDR-induced NF-κB-mediated expression of IL-12 and CCR7. Altogether, our data show that exposure to LDR resulted in a hormetic effect on DCs regarding CCR7-mediated migration and IL-12 production by activating the ATM/NF-κB pathway.

  14. Estrogen receptor alpha and nuclear factor Y coordinately regulate the transcription of the SUMO-conjugating UBC9 gene in MCF-7 breast cancer cells.

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    Shibo Ying

    Full Text Available UBC9 encodes a protein that conjugates small ubiquitin-related modifier (SUMO to target proteins thereby changing their functions. Recently, it was noted that UBC9 expression and activity play a role in breast tumorigenesis and response to anticancer drugs. However, the underlying mechanism is poorly understood. To investigate the transcriptional regulation of the UBC9 gene, we identified and characterized its promoter and cis-elements. Promoter activity was tested using luciferase reporter assays. The binding of transcription factors to the promoter was detected by chromatin immunoprecipitation (ChIP, and their functional role was confirmed by siRNA knockdown. UBC9 mRNA and protein levels were measured by quantitative reverse transcription PCR and Western blot analysis, respectively. An increased expression of UBC9 mRNA and protein was found in MCF-7 breast cancer cells treated with 17β-estradiol (E2. Analysis of various deletion mutants revealed a 137 bp fragment upstream of the transcription initiation site to be sufficient for reporter gene transcription. Mutations of putative estrogen receptor α (ER-α (one imperfect estrogen response element, ERE and/or nuclear factor Y (NF-Y binding sites (two CCAAT boxes markedly reduced promoter activity. Similar results were obtained in ER-negative MDA-MB-231 cells except that the ERE mutation did not affect promoter activity. Additionally, promoter activity was stimulated upon E2 treatment and overexpression of ER-α or NF-YA in MCF-7 cells. ChIP confirmed direct binding of both transcription factors to the UBC9 promoter in vivo. Furthermore, UBC9 expression was diminished by ER-α and NF-Y siRNAs on the mRNA and protein levels. In conclusion, we identified the proximal UBC9 promoter and provided evidence that ER-α and NF-Y regulate UBC9 expression on the transcriptional level in response to E2 in MCF-7 cells. These findings may contribute to a better understanding of the regulation of UBC9 in ER

  15. NF-kappaB mediates FGF signal regulation of msx-1 expression.

    Science.gov (United States)

    Bushdid, P B; Chen, C L; Brantley, D M; Yull, F; Raghow, R; Kerr, L D; Barnett, J V

    2001-09-01

    The nuclear factor-kappaB (NF-kappaB) family of transcription factors is involved in proliferation, differentiation, and apoptosis in a stage- and cell-dependent manner. Recent evidence has shown that NF-kappaB activity is necessary for both chicken and mouse limb development. We report here that the NF-kappaB family member c-rel and the homeodomain gene msx-1 have partially overlapping expression patterns in the developing chick limb. In addition, inhibition of NF-kappaB activity resulted in a decrease in msx-1 mRNA expression. Sequence analysis of the msx-1 promoter revealed three potential kappaB-binding sites similar to the interferon-gamma (IFN-gamma) kappaB-binding site. These sites bound to c-Rel, as shown by electrophoretic mobility shift assay (EMSA). Furthermore, inhibition of NF-kappaB activity significantly reduced transactivation of the msx-1 promoter in response to FGF-2/-4, known stimulators of msx-1 expression. These results suggest that NF-kappaB mediates the FGF-2/-4 signal regulation of msx-1 gene expression. Copyright 2001 Academic Press.

  16. Mechanisms of inhibition of zinc-finger transcription factors by selenium compounds ebselen and selenite.

    Science.gov (United States)

    Larabee, Jason L; Hocker, James R; Hanas, Jay S

    2009-03-01

    The anti-inflammatory selenium compounds, ebselen (2-phenyl-1,2-benzisoselenazol-3[2H]-one) and selenite, were found to alter the DNA binding mechanisms and structures of cysteine-rich zinc-finger transcription factors. As assayed by DNase I protection, DNA binding by TFIIIA (transcription factor IIIA, prototypical Cys(2)His(2) zinc finger protein), was inhibited by micromolar amounts of ebselen. In a gel shift assay, ebselen inhibited the Cys(2)His(2) zinc finger-containing DNA binding domain (DBD) of the NF-kappaB mediated transcription factor Sp1. Ebselen also inhibited DNA binding by the p50 subunit of the pro-inflammatory Cys-containing NF-kappaB transcription factor. Electrospray ionization mass spectrometry (ESI-MS) was utilized to elucidate mechanisms of chemical interaction between ebselen and a zinc-bound Cys(2)His(2) zinc finger polypeptide modeled after the third finger of Sp1 (Sp1-3). Exposing Sp1-3 to micromolar amounts of ebselen resulted in Zn(2+) release from this peptide and the formation of a disulfide bond by oxidation of zinc finger SH groups, the likely mechanism for DNA binding inhibition. Selenite was shown by ESI-MS to also eject zinc from Sp1-3 as well as induce disulfide bond formation through SH oxidation. The selenite-dependent inhibition/oxidation mechanism differed from that of ebselen by inducing the formation of a stable selenotrisulfide bond. Selenite-induced selenotrisulfide formation was dependent upon the structure of the Cys(2)His(2) zinc finger as alteration in the finger structure enhanced this reaction as well as selenite-dependent zinc release. Ebselen and selenite-dependent inhibition/oxidation of Cys-rich zinc finger proteins, with concomitant release of zinc and finger structural changes, points to mechanisms at the atomic and protein level for selenium-induced alterations in Cys-rich proteins, and possible amelioration of certain inflammatory, neurodegenerative, and oncogenic responses.

  17. Transcriptional profiling in human HaCaT keratinocytes in response to kaempferol and identification of potential transcription factors for regulating differential gene expression

    Science.gov (United States)

    Kang, Byung Young; Lee, Ki-Hwan; Lee, Yong Sung; Hong, Il; Lee, Mi-Ock; Min, Daejin; Chang, Ihseop; Hwang, Jae Sung; Park, Jun Seong; Kim, Duck Hee

    2008-01-01

    Kaempferol is the major flavonol in green tea and exhibits many biomedically useful properties such as antioxidative, cytoprotective and anti-apoptotic activities. To elucidate its effects on the skin, we investigated the transcriptional profiles of kaempferol-treated HaCaT cells using cDNA microarray analysis and identified 147 transcripts that exhibited significant changes in expression. Of these, 18 were up-regulated and 129 were down-regulated. These transcripts were then classified into 12 categories according to their functional roles: cell adhesion/cytoskeleton, cell cycle, redox homeostasis, immune/defense responses, metabolism, protein biosynthesis/modification, intracellular transport, RNA processing, DNA modification/ replication, regulation of transcription, signal transduction and transport. We then analyzed the promoter sequences of differentially-regulated genes and identified over-represented regulatory sites and candidate transcription factors (TFs) for gene regulation by kaempferol. These included c-REL, SAP-1, Ahr-ARNT, Nrf-2, Elk-1, SPI-B, NF-κB and p65. In addition, we validated the microarray results and promoter analyses using conventional methods such as real-time PCR and ELISA-based transcription factor assay. Our microarray analysis has provided useful information for determining the genetic regulatory network affected by kaempferol, and this approach will be useful for elucidating gene-phytochemical interactions. PMID:18446059

  18. Cancer Cell Growth Inhibitory Effect of Bee Venom via Increase of Death Receptor 3 Expression and Inactivation of NF-kappa B in NSCLC Cells

    Directory of Open Access Journals (Sweden)

    Kyung Eun Choi

    2014-07-01

    Full Text Available Our previous findings have demonstrated that bee venom (BV has anti-cancer activity in several cancer cells. However, the effects of BV on lung cancer cell growth have not been reported. Cell viability was determined with trypan blue uptake, soft agar formation as well as DAPI and TUNEL assay. Cell death related protein expression was determined with Western blotting. An EMSA was used for nuclear factor kappaB (NF-κB activity assay. BV (1–5 μg/mL inhibited growth of lung cancer cells by induction of apoptosis in a dose dependent manner in lung cancer cell lines A549 and NCI-H460. Consistent with apoptotic cell death, expression of DR3 and DR6 was significantly increased. However, deletion of DRs by small interfering RNA significantly reversed BV induced cell growth inhibitory effects. Expression of pro-apoptotic proteins (caspase-3 and Bax was concomitantly increased, but the NF-κB activity and expression of Bcl-2 were inhibited. A combination treatment of tumor necrosis factor (TNF-like weak inducer of apoptosis, TNF-related apoptosis-inducing ligand, docetaxel and cisplatin, with BV synergistically inhibited both A549 and NCI-H460 lung cancer cell growth with further down regulation of NF-κB activity. These results show that BV induces apoptotic cell death in lung cancer cells through the enhancement of DR3 expression and inhibition of NF-κB pathway.

  19. Protein Kinases and Transcription Factors Activation in Response to UV-Radiation of Skin: Implications for Carcinogenesis

    OpenAIRE

    Laurence A. Marchat; Elena Aréchaga Ocampo; Mavil López Casamichana; Carlos Pérez-Plasencia; César López-Camarillo; Elizbeth Álvarez-Sánchez

    2011-01-01

    Solar ultraviolet (UV) radiation is an important environmental factor that leads to immune suppression, inflammation, photoaging, and skin carcinogenesis. Here, we reviewed the specific signal transduction pathways and transcription factors involved in the cellular response to UV-irradiation. Increasing experimental data supporting a role for p38, MAPK, JNK, ERK1/2, and ATM kinases in the response network to UV exposure is discussed. We also reviewed the participation of NF-?B, AP-1, and NRF2...

  20. Molecular imaging of transcriptional regulation during inflammation

    Directory of Open Access Journals (Sweden)

    Carlsen Harald

    2010-04-01

    Full Text Available Abstract Molecular imaging enables non-invasive visualization of the dynamics of molecular processes within living organisms in vivo. Different imaging modalities as MRI, SPECT, PET and optic imaging are used together with molecular probes specific for the biological process of interest. Molecular imaging of transcription factor activity is done in animal models and mostly in transgenic reporter mice, where the transgene essentially consists of a promoter that regulates a reporter gene. During inflammation, the transcription factor NF-κB is widely involved in orchestration and regulation of the immune system and almost all imaging studies in this field has revolved around the role and regulation of NF-κB. We here present a brief introduction to experimental use and design of transgenic reporter mice and a more extensive review of the various studies where molecular imaging of transcriptional regulation has been applied during inflammation.

  1. UV-induced transcription from the human immunodeficiency virus type 1 (HIV-1) long terminal repeat and UV-induced secretion of an extracellular factor that induces HIV-1 transcription in nonirradiated cells

    International Nuclear Information System (INIS)

    Stein, B.; Kraemer, M.R.; Rahmsdorf, H.J.; Ponta, H.; Herrlich, P.

    1989-01-01

    UV irradiation, but not visible sunlight, induces the transcription of human immunodeficiency virus type 1 (HIV-1). Chimeric constructs carrying all or parts of the HIV-1 long terminal repeat linked to an indicator gene were transfected into HeLa cells or murine and human T-cell lines, and their response to irradiation was tested. The cis-acting element conferring UV responsiveness is identical to the sequence binding transcription factor NF kappa B. UV irradiation enhances NF kappa B binding activity as assayed by gel retardation experiments. Interestingly, the requirement for UV irradiation can be replaced by cocultivation of transfected cells with UV-irradiated nontransfected (HIV-1-negative) cells. A UV-induced extracellular protein factor is detected in the culture medium conditioned by UV-treated cells. The factor is produced upon UV irradiation by several murine and human cell lines, including HeLa, Molt-4, and Jurkat, and acts on several cells. These data suggest that the UV response of keratinocytes in human skin can be magnified and spread to deeper layers that are more shielded, including the Langerhans cells, and that this indirect UV response may contribute to the activation of HIV-1 in humans

  2. Post-Translational Modifications of RelB NF-κB Subunit and Associated Functions

    Directory of Open Access Journals (Sweden)

    Véronique Baud

    2016-05-01

    Full Text Available The family of NF-κB transcription factors plays a key role in diverse biological processes, such as inflammatory and immune responses, cell survival and tumor development. Beyond the classical NF-κB activation pathway, a second NF-κB pathway has more recently been uncovered, the so-called alternative NF-κB activation pathway. It has been shown that this pathway mainly controls the activity of RelB, a member of the NF-κB family. Post-translational modifications, such as phosphorylation, acetylation, methylation, ubiquitination and SUMOylation, have recently emerged as a strategy for the fine-tuned regulation of NF-κB. Our review discusses recent progress in the understanding of RelB regulation by post-translational modifications and the associated functions in normal and pathological conditions.

  3. Identification of a novel TIF-IA-NF-κB nucleolar stress response pathway.

    Science.gov (United States)

    Chen, Jingyu; Lobb, Ian T; Morin, Pierre; Novo, Sonia M; Simpson, James; Kennerknecht, Kathrin; von Kriegsheim, Alex; Batchelor, Emily E; Oakley, Fiona; Stark, Lesley A

    2018-06-05

    p53 as an effector of nucleolar stress is well defined, but p53 independent mechanisms are largely unknown. Like p53, the NF-κB transcription factor plays a critical role in maintaining cellular homeostasis under stress. Many stresses that stimulate NF-κB also disrupt nucleoli. However, the link between nucleolar function and activation of the NF-κB pathway is as yet unknown. Here we demonstrate that artificial disruption of the PolI complex stimulates NF-κB signalling. Unlike p53 nucleolar stress response, this effect does not appear to be linked to inhibition of rDNA transcription. We show that specific stress stimuli of NF-κB induce degradation of a critical component of the PolI complex, TIF-IA. This degradation precedes activation of NF-κB and is associated with increased nucleolar size. It is mimicked by CDK4 inhibition and is dependent upon a novel pathway involving UBF/p14ARF and S44 of the protein. We show that blocking TIF-IA degradation blocks stress effects on nucleolar size and NF-κB signalling. Finally, using ex vivo culture, we show a strong correlation between degradation of TIF-IA and activation of NF-κB in freshly resected, human colorectal tumours exposed to the chemopreventative agent, aspirin. Together, our study provides compelling evidence for a new, TIF-IA-NF-κB nucleolar stress response pathway that has in vivo relevance and therapeutic implications.

  4. The murine cytomegalovirus M35 protein antagonizes type I IFN induction downstream of pattern recognition receptors by targeting NF-κB mediated transcription.

    Directory of Open Access Journals (Sweden)

    Baca Chan

    2017-05-01

    Full Text Available The type I interferon (IFN response is imperative for the establishment of the early antiviral immune response. Here we report the identification of the first type I IFN antagonist encoded by murine cytomegalovirus (MCMV that shuts down signaling following pattern recognition receptor (PRR sensing. Screening of an MCMV open reading frame (ORF library identified M35 as a novel and strong negative modulator of IFNβ promoter induction following activation of both RNA and DNA cytoplasmic PRR. Additionally, M35 inhibits the proinflammatory cytokine response downstream of Toll-like receptors (TLR. Using a series of luciferase-based reporters with specific transcription factor binding sites, we determined that M35 targets NF-κB-, but not IRF-mediated, transcription. Expression of M35 upon retroviral transduction of immortalized bone marrow-derived macrophages (iBMDM led to reduced IFNβ transcription and secretion upon activation of stimulator of IFN genes (STING-dependent signaling. On the other hand, M35 does not antagonize interferon-stimulated gene (ISG 56 promoter induction or ISG transcription upon exogenous stimulation of the type I IFN receptor (IFNAR. M35 is present in the viral particle and, upon MCMV infection of fibroblasts, is immediately shuttled to the nucleus where it exerts its immunomodulatory effects. Deletion of M35 from the MCMV genome and hence from the viral particle resulted in elevated type I IFN transcription and secretion in vitro and in vivo. In the absence of M35, lower viral titers are observed during acute infection of the host, and productive infection in the salivary glands was not detected. In conclusion, the M35 protein is released by MCMV immediately upon infection in order to deftly inhibit the antiviral type I IFN response by targeting NF-κB-mediated transcription. The identification of this novel viral protein reinforces the importance of timely countermeasures in the complex relationship between virus and host.

  5. Protective protein/cathepsin A down-regulates osteoclastogenesis by associating with and degrading NF-kappaB p50/p65.

    Science.gov (United States)

    Masuhara, Masaaki; Sato, Takuya; Hada, Naoto; Hakeda, Yoshiyuki

    2009-01-01

    Disruption of the cooperative function balance between osteoblasts and osteoclasts causes various bone disorders, some of which are attributed to abnormal osteoclast recruitment. Osteoclast differentiation is dependent on the receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) as well as the macrophage colony-stimulating factor. The osteoclast formation induced by cytokines requires activation of NF-kappaB, AP-1 and nuclear factor of activated T cells c1. However, osteoclasts are not the only cell types that express these transcription factors, suggesting that some unknown molecules specific for osteoclasts may associate with the transcription factors. Here, we explored the possibility of molecules binding directly to NF-kappaB and cloned protective protein/cathepsin A (PPCA) by yeast two-hybrid screening using a cDNA library of osteoclast precursors. Forced expression of PPCA with p50/p65 in HEK293 cells decreased both the level of p50/p65 proteins and the transcriptional activity. Abundant PPCA was detected in the lysosomes of the transfected HEK293 cells, but a small amount of this enzyme was also present in the cytosolic fraction. In addition, over-expression of PPCA caused the disappearance of p50/p65 in both the lysosomal and cytosolic fractions. PPCA was expressed throughout osteoclastogenesis, and the expression was slightly up-regulated by RANKL signaling. Knockdown of PPCA in osteoclast precursors with PPCA siRNA stimulated binding of nuclear proteins to oligonucleotides containing an NF-kappaB binding motif and increased osteoclastogenesis. Our present results indicate a novel role for PPCA in osteoclastogenesis via down-regulation of NF-kappaB activity and suggest a new function for PPCA as an NF-kappaB-degrading enzyme in addition to its known multifunctional properties.

  6. Programmable Oligomers Targeting 5′-GGGG-3′ in the Minor Groove of DNA and NF-κB Binding Inhibition

    Science.gov (United States)

    Chenoweth, David M.; Poposki, Julie A.; Marques, Michael A.; Dervan, Peter B.

    2009-01-01

    A series of hairpin oligomers containing benzimidazole (Bi) and imidazopyridine (Ip) rings were synthesized and screened to target 5′-WGGGGW-3′, a core sequence in the DNA binding site of NF-κB, a prolific transcription factor important in biology and disease. Five Bi and Ip containing oligomers bound to the 5′-WGGGGW-3′ site with high affinity. One of the oligomers (Im-Im-Im-Im-γ-PyBi-PyBi-β-Dp) was able to inhibit DNA binding by the transcription factor NF-κB. PMID:17095230

  7. Hyperammonemia in cirrhosis induces transcriptional regulation of myostatin by an NF-κB–mediated mechanism

    Science.gov (United States)

    Qiu, Jia; Thapaliya, Samjhana; Runkana, Ashok; Yang, Yu; Tsien, Cynthia; Mohan, Maradumane L.; Narayanan, Arvind; Eghtesad, Bijan; Mozdziak, Paul E.; McDonald, Christine; Stark, George R.; Welle, Stephen; Naga Prasad, Sathyamangla V.; Dasarathy, Srinivasan

    2013-01-01

    Loss of muscle mass, or sarcopenia, is nearly universal in cirrhosis and adversely affects patient outcome. The underlying cross-talk between the liver and skeletal muscle mediating sarcopenia is not well understood. Hyperammonemia is a consistent abnormality in cirrhosis due to impaired hepatic detoxification to urea. We observed elevated levels of ammonia in both plasma samples and skeletal muscle biopsies from cirrhotic patients compared with healthy controls. Furthermore, skeletal muscle from cirrhotics had increased expression of myostatin, a known inhibitor of skeletal muscle accretion and growth. In vivo studies in mice showed that hyperammonemia reduced muscle mass and strength and increased myostatin expression in wild-type compared with postdevelopmental myostatin knockout mice. We postulated that hyperammonemia is an underlying link between hepatic dysfunction in cirrhosis and skeletal muscle loss. Therefore, murine C2C12 myotubes were treated with ammonium acetate resulting in intracellular concentrations similar to those in cirrhotic muscle. In this system, we demonstrate that hyperammonemia stimulated myostatin expression in a NF-κB–dependent manner. This finding was also observed in primary murine muscle cell cultures. Hyperammonemia triggered activation of IκB kinase, NF-κB nuclear translocation, binding of the NF-κB p65 subunit to specific sites within the myostatin promoter, and stimulation of myostatin gene transcription. Pharmacologic inhibition or gene silencing of NF-κB abolished myostatin up-regulation under conditions of hyperammonemia. Our work provides unique insights into hyperammonemia-induced myostatin expression and suggests a mechanism by which sarcopenia develops in cirrhotic patients. PMID:24145431

  8. The transcription factor DREAM represses A20 and mediates inflammation

    OpenAIRE

    Tiruppathi, Chinnaswamy; Soni, Dheeraj; Wang, Dong-Mei; Xue, Jiaping; Singh, Vandana; Thippegowda, Prabhakar B.; Cheppudira, Bopaiah P.; Mishra, Rakesh K.; DebRoy, Auditi; Qian, Zhijian; Bachmaier, Kurt; Zhao, Youyang; Christman, John W.; Vogel, Stephen M.; Ma, Averil

    2014-01-01

    Here we show that the transcription-repressor DREAM binds to the A20 promoter to repress the expression of A20, the deubiquitinase suppressing inflammatory NF-κB signaling. DREAM-deficient (Dream−/− ) mice displayed persistent and unchecked A20 expression in response to endotoxin. DREAM functioned by transcriptionally repressing A20 through binding to downstream regulatory elements (DREs). In contrast, USF1 binding to the DRE-associated E-box domain activated A20 expression in response to inf...

  9. WRKY transcription factors

    Science.gov (United States)

    Bakshi, Madhunita; Oelmüller, Ralf

    2014-01-01

    WRKY transcription factors are one of the largest families of transcriptional regulators found exclusively in plants. They have diverse biological functions in plant disease resistance, abiotic stress responses, nutrient deprivation, senescence, seed and trichome development, embryogenesis, as well as additional developmental and hormone-controlled processes. WRKYs can act as transcriptional activators or repressors, in various homo- and heterodimer combinations. Here we review recent progress on the function of WRKY transcription factors in Arabidopsis and other plant species such as rice, potato, and parsley, with a special focus on abiotic, developmental, and hormone-regulated processes. PMID:24492469

  10. NF-{kappa}B p50 promotes tumor cell invasion through negative regulation of invasion suppressor gene CRMP-1 in human lung adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Gao [Cancer Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University, Hospital, Taipei, Taiwan (China); Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Yeh, P Y [Cancer Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Department of Oncology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 10016, Taiwan (China); Lu, Y -S [Cancer Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University, Hospital, Taipei, Taiwan (China); Department of Oncology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 10016, Taiwan, ROC (China); Chang, W C [Cancer Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Kuo, M -L [Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Cheng, A -L [Cancer Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan (China); National Center of Excellence for Clinical Trial and Research, National Taiwan University, Hospital, Taipei, Taiwan (China); Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Department of Oncology, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 10016, Taiwan (China); Department of Internal Medicine, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 10016, Taiwan (China)], E-mail: alcheng@ntu.edu.tw

    2008-11-14

    Lung adenocarcinoma Cl1-5 cells were selected from parental Cl1-0 cells based on their high metastatic potential. In a previous study, CRMP-1, an invasion suppressor gene, was shown to be suppressed in Cl1-5 cells. However, the regulation of CRMP-1 expression has not been explored. In this study, we showed nuclear factor-{kappa}B controls CRMP-1 expression. The electromobility shift assay showed that while Cl1-0 cells exhibited low NF-{kappa}B activity in response to TNF-{alpha}, an abundance of basal and TNF-{alpha}-induced NF-{kappa}B-DNA complex was detected in Cl1-5 cells. Supershift-coupled EMSA and Western blotting of nuclear proteins, however, revealed p50 protein, but not classic p65/p50 heterodimer in the complex. ChIP and EMSA demonstrated that p50 binds to a {kappa}B site residing between -1753 and -1743 of the CRMP-1 promoter region. Transfection of antisense p50 gene into Cl1-5 cells increased the CRMP-1 protein level and decreased the invasive activity of Cl1-5 cells.

  11. Cell Autonomous and Non-Autonomous Functions of IKKβ and NF-κB during the Pathogenesis of Gastrointestinal Tumors

    International Nuclear Information System (INIS)

    Fang, Hsin-Yu; Greten, Florian R.

    2011-01-01

    Genetic studies describing a link between cancer and inflammation have increased recently. Activation of the transcription factor nuclear factor-κB (NF-κB) and its effector pathways has been proposed to be the missing link between these two processes. NF-κB is persistently activated in several types of tumors. However, NF-κB has a distinct role in cancer cells and in inflammatory cells. While in tumor cells NF-κB controls cell survival, in inflammatory cells NF-κB activates genes that encode pro-inflammatory cytokines which further act in a paracrine manner within the tumor microenvironment to contribute to tumorigenesis. Inactivation of NF-κB can also reduce chemoresistance and radioresistance of cancer cells. Therefore, specific NF-κB inhibition in combination with cytotoxic drugs and/or irradiation represents a very promising strategy for cancer therapy

  12. Caractérisation des processus d'ubiquitination régulant le facteur de transcription NF-kappaB au cours de l’activation lymphocytaire Rôle de l’E3 ligase TRIM13 et de la déubiquitinase USP34

    OpenAIRE

    Hatchi , Emeline

    2014-01-01

    The transcription factor NF-KappaB plays a critical role in the development, homeostasis, the survival of the immune system, but also in the propagation of certain lymphomas. The optimal activation of NF-KappaB in response to the engagement of many immunoreceptors rely on the implementation of large signalosomes where specific adaptors are recruited and poly-Ubiquitinylated in a non-Degradative manner. In response to proinflammatory cytokines or activation of antigen receptors, these Ubiquiti...

  13. Altered binding of human histone gene transcription factors during the shutdown of proliferation and onset of differentiation in HL-60 cells

    International Nuclear Information System (INIS)

    Stein, G.; Lian, J.; Stein, J.; Shalhoub, V.; Wright, K.; Pauli, U.; Van Wijnen, A.; Briggs, R.

    1989-01-01

    Two sites of protein-DNA interaction have been identified in vivo and in vitro in the proximal promoter regions of an H4 and an H3 human histone gene. In proliferating cells, these genes are transcribed throughout the cell cycle, and both the more distal site I and the proximal site II are occupied by promoter-binding factors. In this report the authors demonstrate that during the shutdown of proliferation and onset of differentiation of the human promyelocytic leukemia cell line HL-60 into cells that exhibit phenotypic properties of monocytes, histone gene expression is down-regulated at the level of transcription. In vivo occupancy of site I by promoter factors persists in the differentiated HL-60 cells, but protein-DNA interactions at site II are selectively lost. Furthermore, in vitro binding activity of the site II promoter factor HiNF-D is lost in differentiated cells, and nuclear extracts from differentiated cells do not support in vitro transcription of these histone genes. The results suggest that the interaction of HiNF-D with proximal promoter site II sequences plays a primary role in rendering cell growth-regulated histone genes transcribable in proliferating cells. It appears that while cell-cycle control of histone gene expression is mediated by both transcription and mRNA stability, with the shutdown of proliferation and onset of differentiation, histone gene expression is regulated at the transcriptional level

  14. NF-κB Signaling Regulates Epstein–Barr Virus BamHI-Q-Driven EBNA1 Expression

    Directory of Open Access Journals (Sweden)

    Rob J. A. Verhoeven

    2018-04-01

    Full Text Available Epstein–Barr virus (EBV nuclear antigen 1 (EBNA1 is one of the few viral proteins expressed by EBV in nasopharyngeal carcinoma (NPC, most likely because of its essential role in maintaining the viral genome in EBV-infected cells. In NPC, EBNA1 expression is driven by the BamHI-Q promoter (Qp, which is regulated by both cellular and viral factors. We previously determined that the expression of another group of EBV transcripts, BamHI-A rightward transcripts (BARTs, is associated with constitutively activated nuclear factor-κB (NF-κB signaling in NPC cells. Here, we show that, like the EBV BART promoter, the EBV Qp also responds to NF-κB signaling. NF-κB p65, but not p50, can activate Qp in vitro, and NF-κB signaling regulates Qp-EBNA1 expression in NPC cells, as well as in other EBV-infected epithelial cells. The introduction of mutations in the putative NF-κB site reduced Qp activation by the NF-κB p65 subunit. Binding of p65 to Qp was shown by chromatin immunoprecipitation (ChIP analysis, while electrophoretic mobility shift assays (EMSAs demonstrated that p50 can also bind to Qp. Inhibition of NF-κB signaling by the IκB kinase inhibitor PS-1145 resulted in the downregulation of Qp-EBNA1 expression in C666-1 NPC cells. Since EBNA1 has been reported to block p65 activation by inhibiting IKKα/β through an unknown mechanism, we suggest that, in NPC, NF-κB signaling and EBNA1 may form a regulatory loop which supports EBV latent gene expression, while also limiting NF-κB activity. These findings emphasize the role of NF-κB signaling in the regulation of EBV latency in EBV-associated tumors.

  15. Regulation of NF-κB activity in astrocytes: effects of flavonoids at dietary-relevant concentrations

    International Nuclear Information System (INIS)

    Spilsbury, Alison; Vauzour, David; Spencer, Jeremy P.E.; Rattray, Marcus

    2012-01-01

    Highlights: ► We tested the hypothesis that low concentrations of flavonoids inhibit NF-κB in astrocytes. ► Primary cultured astrocytes possess a functional κB-system, measured using luciferase assays. ► Seven flavonoids (100 nM–1 μM) failed to reduce NF-κB activity in astrocytes. ► Four flavonoids (100 nM–1 μM) failed to reduce TNFa-stimulated NF-κB activity in astrocytes. ► (−)-Epicatechin did not regulate nuclear translocation of the NF-κB subunit, p65. -- Abstract: Neuroinflammation plays an important role in the progression of neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease. Sustained activation of nuclear transcription factor κB (NF-κB) is thought to play an important role in the pathogenesis of neurodegenerative disorders. Flavonoids have been shown to possess antioxidant and anti-inflammatory properties and we investigated whether flavonoids, at submicromolar concentrations relevant to their bioavailability from the diet, were able to modulate NF-κB signalling in astrocytes. Using luciferase reporter assays, we found that tumour necrosis factor (TNFα, 150 ng/ml) increased NF-κB-mediated transcription in primary cultures of mouse cortical astrocytes, which was abolished on co-transfection of a dominant-negative IκBα construct. In addition, TNFα increased nuclear localisation of p65 as shown by immunocytochemistry. To investigate potential flavonoid modulation of NF-κB activity, astrocytes were treated with flavonoids from different classes; flavan-3-ols ((−)-epicatechin and (+)-catechin), flavones (luteolin and chrysin), a flavonol (kaempferol) or the flavanones (naringenin and hesperetin) at dietary-relevant concentrations (0.1–1 μM) for 18 h. None of the flavonoids modulated constitutive or TNFα-induced NF-κB activity. Therefore, we conclude that NF-κB signalling in astrocytes is not a major target for flavonoids.

  16. Repression of MHC class I transcription by HPV16E7 through interaction with a putative RXRβ motif and NF-κB cytoplasmic sequestration

    International Nuclear Information System (INIS)

    Li, Hui; Zhan, TaiLan; Li, Chang; Liu, Mugen; Wang, Qing K.

    2009-01-01

    Down-regulation of transcription of the MHC class I genes in HPV16 tumorigenic cells is partly due to HPV16E7 associated with the MHC class I promoter and repressed chromatin activation. In this study, we further demonstrated that HPV16E7 is physically associated with a putative RXRβ binding motif (GGTCA) of the proximal promoter of the MHC class I genes by using reporter transcriptional assays and chromatin immunoprecipitation assays. Our data also provide evidence that HPV16E7 inhibits TNF-α-induced up-regulation of MHC class I transcription by impaired nuclear translocation of NF-κB. More importantly, CaSki tumor cells treated with TSA and transfected with the constitutively active mutant form of IKK-α (which can activate NF-κB directly) showed a maximal level of up-regulation of MHC-I expression. Taken together, our results suggest that HPV16E7 may employ two independent mechanisms to ensure that either the constitutive or inducible transcription of MHC class I genes is down-regulated.

  17. Circumvention of nuclear factor kappaB-induced chemoresistance by cytoplasmic-targeted anthracyclines.

    Science.gov (United States)

    Bilyeu, Jennifer D; Panta, Ganesh R; Cavin, Lakita G; Barrett, Christina M; Turner, Eddie J; Sweatman, Trevor W; Israel, Mervyn; Lothstein, Leonard; Arsura, Marcello

    2004-04-01

    Nuclear factor kappaB (NF-kappaB) has been implicated in inducible chemoresistance against anthracyclines. In an effort to improve the cytotoxicity of anthracyclines while reducing their cardiotoxic effects, we have developed a novel class of extranuclear-localizing 14-O-acylanthracyclines that bind to the phorbol ester/diacylglycerol-binding C1b domain of conventional and novel protein kinase C (PKC) isoforms, thereby promoting an apoptotic response. Because PKCs have been shown to be involved in NF-kappaB activation, in this report, we determined the mechanism of NF-kappaB activation by N-benzyladriamycin-14-valerate (AD 198) and N-benzyladriamycin-14-pivalate (AD 445), two novel 14-O-acylanthracylines. We show that the induction of NF-kappaB activity in response to drug treatment relies on the activation of PKC-delta and NF-kappaB-activating kinase (NAK), independent of ataxia telengectasia mutated and p53 activities. In turn, NAK activates the IKK complex through phosphorylation of the IKK-2 subunit. We find that neither NF-kappaB activation nor ectopic expression of Bcl-X(L) confers protection from AD 198-induced cell killing. Overall, our data indicate that activation of novel PKC isoforms by cytoplasmic-targeted 14-O-acylanthracyclines promotes an apoptotic response independent of DNA damage, which is unimpeded by inducible activation of NF-kappaB.

  18. Human Papillomavirus type 16 E6 and E 7 proteins alter NF-kB in cultured cervical epithelial cells and inhibition of NF-kB promotes cell growth and immortalization

    Science.gov (United States)

    Vandermark, Erik R.; Deluca, Krysta A.; Gardner, Courtney R.; Marker, Daniel F.; Schreiner, Cynthia N.; Strickland, David A.; Wilton, Katelynn M.; Mondal, Sumona; Woodworth, Craig D.

    2012-01-01

    The NF-kB family of transcription factors regulates important biological functions including cell growth, survival and the immune response. We found that Human Papillomavirus type 16 (HPV-16) E7 and E6/E7 proteins inhibited basal and TNF-alpha-inducible NF-kB activity in human epithelial cells cultured from the cervical transformation zone, the anatomic region where most cervical cancers develop. In contrast, HPV-16 E6 regulated NF-kB in a cell type- and cell growth-dependent manner. NF-kB influenced immortalization of cervical cells by HPV16. Inhibition of NF-kB by an IkB alpha repressor mutant increased colony formation and immortalization by HPV-16. In contrast, activation of NF-kB by constitutive expression of p65 inhibited proliferation and immortalization. Our results suggest that inhibition of NF-kB by HPV-16 E6/E7 contributes to immortalization of cells from the cervical transformation zone. PMID:22284893

  19. Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder.

    Science.gov (United States)

    Zhao, Xiao-Juan; Yang, Yan-Zi; Zheng, Yan-Jing; Wang, Shan-Chun; Gu, Hong-Mei; Pan, Ying; Wang, Shui-Juan; Xu, Hong-Jiang; Kong, Ling-Dong

    2017-08-15

    Magnesium isoglycyrrhizinate as a hepatoprotective agent possesses immune modulation and anti-inflammation, and treats liver diseases. But its effects on immunological-inflammatory and metabolic profiles for metabolic syndrome with liver injury and underlying potential mechanisms are not fully understood. In this study, magnesium isoglycyrrhizinate alleviated liver inflammation and lipid accumulation in fructose-fed rats with metabolic syndrome. It also suppressed hepatic inflammatory signaling activation by reducing protein levels of phosphorylation of nuclear factor-kappa B p65 (p-NF-κB p65), inhibitor of nuclear factor kappa-B kinase α/β (p-IKKα/β) and inhibitor of NF-κB α (p-IκBα) as well as nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC) and Caspase-1 in rats, being consistent with its reduction of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and IL-6 levels. Furthermore, magnesium isoglycyrrhizinate modulated lipid metabolism-related genes characterized by up-regulating peroxisome proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase-1 (CPT-1), and down-regulating sensor for fatty acids to control-1 (SREBP-1) and stearoyl-CoA desaturase 1 (SCD-1) in the liver of fructose-fed rats, resulting in the reduction of triglyceride and total cholesterol levels. These effective actions were further confirmed in fructose-exposed BRL-3A and HepG2 cells. The molecular mechanisms underpinning these observations suggest that magnesium isoglycyrrhizinate may inhibit NF-κB/NLRP3 inflammasome activation to reduce immunological-inflammatory response, which in turn may prevent liver lipid metabolic disorder and accumulation under high fructose condition. Thus, blockade of NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder by magnesium isoglycyrrhizinate may be the potential therapeutic approach for improving fructose-induced liver injury with

  20. Glucocorticoids facilitate the transcription from the human cytomegalovirus major immediate early promoter in glucocorticoid receptor- and nuclear factor-I-like protein-dependent manner

    International Nuclear Information System (INIS)

    Inoue-Toyoda, Maki; Kato, Kohsuke; Nagata, Kyosuke; Yoshikawa, Hiroyuki

    2015-01-01

    Human cytomegalovirus (HCMV) is a common and usually asymptomatic virus agent in healthy individuals. Initiation of HCMV productive infection depends on expression of the major immediate early (MIE) genes. The transcription of HCMV MIE genes is regulated by a diverse set of transcription factors. It was previously reported that productive HCMV infection is triggered probably by elevation of the plasma hydroxycorticoid level. However, it is poorly understood whether the transcription of MIE genes is directly regulated by glucocorticoid. Here, we found that the dexamethasone (DEX), a synthetic glucocorticoid, facilitates the transcription of HCMV MIE genes through the MIE promoter and enhancer in a glucocorticoid receptor (GR)-dependent manner. By competitive EMSA and reporter assays, we revealed that an NF-I like protein is involved in DEX-mediated transcriptional activation of the MIE promoter. Thus, this study supports a notion that the increased level of hydroxycorticoid in the third trimester of pregnancy reactivates HCMV virus production from the latent state. - Highlights: • DEX facilitates the transcription from the HCMV MIE promoter. • GR is involved in DEX-dependent transcription from the HCMV MIE promoter. • A 17 bp repeat is responsible for the HCMV MIE promoter activation by DEX. • An NF-I-like protein is involved in the HCMV MIE promoter activation by DEX

  1. Protein kinase Cη activates NF-κB in response to camptothecin-induced DNA damage

    International Nuclear Information System (INIS)

    Raveh-Amit, Hadas; Hai, Naama; Rotem-Dai, Noa; Shahaf, Galit; Gopas, Jacob; Livneh, Etta

    2011-01-01

    Highlights: → Protein kinase C-eta (PKCη) is an upstream regulator of the NF-κB signaling pathway. → PKCη activates NF-κB in non-stressed conditions and in response to DNA damage. → PKCη regulates NF-κB by activating IκB kinase (IKK) and inducing IκB degradation. -- Abstract: The nuclear factor κB (NF-κB) family of transcription factors participates in the regulation of genes involved in innate- and adaptive-immune responses, cell death and inflammation. The involvement of the Protein kinase C (PKC) family in the regulation of NF-κB in inflammation and immune-related signaling has been extensively studied. However, not much is known on the role of PKC in NF-κB regulation in response to DNA damage. Here we demonstrate for the first time that PKC-eta (PKCη) regulates NF-κB upstream signaling by activating the IκB kinase (IKK) and the degradation of IκB. Furthermore, PKCη enhances the nuclear translocation and transactivation of NF-κB under non-stressed conditions and in response to the anticancer drug camptothecin. We and others have previously shown that PKCη confers protection against DNA damage-induced apoptosis. Our present study suggests that PKCη is involved in NF-κB signaling leading to drug resistance.

  2. Matrine suppresses airway inflammation by downregulating SOCS3 expression via inhibition of NF-κB signaling in airway epithelial cells and asthmatic mice

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Daqing [Department of Respiration, Xi’an Children’s Hospital, Xi’an 710003 (China); Wang, Jing [Department of Neonatology, Xi’an Children’s Hospital, Xi’an 710003 (China); Yang, Niandi [Outpatient Department, School of Aerospace Engineering, Air Force Engineering University, Xi’an 710038 (China); Ma, Haixin, E-mail: drhaixinma@163.com [Department of Quality Control, Xi’an Children’s Hospital, Xi’an 710003 (China)

    2016-08-12

    Matrine has been demonstrated to attenuate allergic airway inflammation. Elevated suppressor of cytokine signaling 3 (SOCS3) was correlated with the severity of asthma. The aim of this study was to investigate the effect of matrine on SOCS3 expression in airway inflammation. In this study, we found that matrine significantly inhibited OVA-induced AHR, inflammatory cell infiltration, goblet cell differentiation, and mucous production in a dose-dependent manner in mice. Matrine also abrogated the level of interleukin (IL)-4 and IL-13, but enhanced interferon (IFN)-γ expression, both in BALF and in lung homogenates. Furthermore, matrine impeded TNF-α-induced the expression of IL-6 and adhesion molecules in airway epithelial cells (BEAS-2B and MLE-12). Additionally, we found that matrine inhibited SOCS3 expression, both in asthmatic mice and TNF-α-stimulated epithelial cells via suppression of the NF-κB signaling pathway by using pcDNA3.1-SOCS3 plasmid, SOCS3 siRNA, or nuclear factor kappa-B (NF-κB) inhibitor PDTC. Conclusions: Matrine suppresses airway inflammation by downregulating SOCS3 expression via inhibition of NF-κB signaling in airway epithelial cells and asthmatic mice. - Highlights: • Matrine attenuates asthmatic symptoms and regulates Th1/Th2 balance in vivo. • Matrine suppresses inflammation responses in vitro. • Matrine decreases SOCS3 expression both in vivo and in vitro. • Matrine inhibits SOCS3 expression by suppressing NF-κB signaling.

  3. Fatigue and gene expression in human leukocytes: Increased NF-κB and decreased glucocorticoid signaling in breast cancer survivors with persistent fatigue

    Science.gov (United States)

    Bower, Julienne E.; Ganz, Patricia A.; Irwin, Michael R.; Arevalo, Jesusa M.G.; Cole, Steve W.

    2013-01-01

    Fatigue is highly prevalent in the general population and is one of the most common side effects of cancer treatment. There is growing evidence that pro-inflammatory cytokines play a role in cancer-related fatigue, although the molecular mechanisms for chronic inflammation and fatigue have not been determined. The current study utilized genome-wide expression microarrays to identify differences in gene expression and associated alterations in transcriptional activity in leukocytes from breast cancer survivors with persistent fatigue (n = 11) and non-fatigued controls (n = 10). We focused on transcription of inflammation-related genes, particularly those responsive to the pro-inflammatory NF-κB transcription control pathway. Further, given the role of glucocorticoids as key regulators of inflammatory processes, we examined transcription of glucocorticoid-responsive genes indicative of potential glucocorticoid receptor (GR) desensitization. Plasma levels of cortisol were also assessed. Consistent with hypotheses, results showed increased expression of transcripts with response elements for NF-κB, and reduced expression of transcripts with response elements for glucocorticoids (p < .05) in fatigued breast cancer survivors. No differences in plasma levels of cortisol were observed. These data indicate that increased activity of pro-inflammatory transcription factors may contribute to persistent cancer-related fatigue and provide insight into potential mechanisms for tonic increases in NF-κB activity, specifically decreased expression of GR anti-inflammatory transcription factors. PMID:20854893

  4. Prolyl hydroxylase-1 regulates hepatocyte apoptosis in an NF-κB-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, Susan F.; Fábián, Zsolt; Schaible, Bettina; Lenihan, Colin R.; Schwarzl, Thomas [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Rodriguez, Javier [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Zheng, Xingnan; Li, Zongwei [Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC (United States); Tambuwala, Murtaza M. [School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, BT52 1SA, Northern Ireland (United Kingdom); Higgins, Desmond G.; O' Meara, Yvonne [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Slattery, Craig [School of Biomolecular and Biomedical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Manresa, Mario C. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Fraisl, Peter; Bruning, Ulrike [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Baes, Myriam [Laboratory for Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven (Belgium); Carmeliet, Peter; Doherty, Glen [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Kriegsheim, Alex von [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Cummins, Eoin P. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); and others

    2016-06-03

    Hepatocyte death is an important contributing factor in a number of diseases of the liver. PHD1 confers hypoxic sensitivity upon transcription factors including the hypoxia inducible factor (HIF) and nuclear factor-kappaB (NF-κB). Reduced PHD1 activity is linked to decreased apoptosis. Here, we investigated the underlying mechanism(s) in hepatocytes. Basal NF-κB activity was elevated in PHD1{sup −/−} hepatocytes compared to wild type controls. ChIP-seq analysis confirmed enhanced binding of NF-κB to chromatin in regions proximal to the promoters of genes involved in the regulation of apoptosis. Inhibition of NF-κB (but not knock-out of HIF-1 or HIF-2) reversed the anti-apoptotic effects of pharmacologic hydroxylase inhibition. We hypothesize that PHD1 inhibition leads to altered expression of NF-κB-dependent genes resulting in reduced apoptosis. This study provides new information relating to the possible mechanism of therapeutic action of hydroxylase inhibitors that has been reported in pre-clinical models of intestinal and hepatic disease. -- Highlights: •Genetic ablation of PHD1 upregulates NF-kappaB (NF-κB) in hepatocytes. •Activation of NF-κB leads to differential DNA-binding of p50/p65 and results in differential regulation of apoptotic genes. •We identified proline 191 in the beta subunit of the I-kappaB kinase as a target for PHD1-mediated hydroxylation. •Blockade of prolyl-4-hydroxylases has been found cytoprotective in liver cells.

  5. Nucleocytoplasmic shuttling of transcription factors

    DEFF Research Database (Denmark)

    Cartwright, P; Helin, K

    2000-01-01

    To elicit the transcriptional response following intra- or extracellular stimuli, the signals need to be transmitted to their site of action within the nucleus. The nucleocytoplasmic shuttling of transcription factors is a mechanism mediating this process. The activation and inactivation...... of the transcriptional response is essential for cells to progress through the cell cycle in a normal manner. The involvement of cytoplasmic and nuclear accessory molecules, and the general nuclear membrane transport components, are essential for this process. Although nuclear import and export for different...... transcription factor families are regulated by similar mechanisms, there are several differences that allow for the specific activation of each transcription factor. This review discusses the general import and export pathways found to be common amongst many different transcription factors, and highlights...

  6. When ubiquitin meets NF-κB: a trove for anti-cancer drug development.

    Science.gov (United States)

    Wu, Zhao-Hui; Shi, Yuling

    2013-01-01

    During the last two decades, the studies on ubiquitination in regulating transcription factor NF-κB activation have elucidated the expanding role of ubiquitination in modulating cellular events by non-proteolytic mechanisms, as well as by proteasomal degradation. The significance of ubiquitination has also been recognized in regulating gene transcription, epigenetic modifications, kinase activation, DNA repair and subcellular translocation. This progress has been translated into novel strategies for developing anti-cancer therapeutics, exemplified by the success of the first FDA-approved proteasome inhibitor drug Bortezomib. Here we discuss the current understanding of the ubiquitin-proteasome system and how it is involved in regulating NF-κB signaling pathways in response to a variety of stimuli. We also focus on the recent progress of anti-cancer drug development targeting various steps of ubiquitination process, and the potential of these drugs in cancer treatment as related to their impact on NF-κB activation.

  7. NF-kappaB signaling mediates vascular smooth muscle endothelin type B receptor expression in resistance arteries

    DEFF Research Database (Denmark)

    Zheng, Jian-Pu; Zhang, Yaping; Edvinsson, Lars

    2010-01-01

    Vascular smooth muscle cells (SMC) endothelin type B (ET(B)) receptor upregulation results in strong vasoconstriction and reduction of local blood flow. We hypothesizes that the underlying molecular mechanisms involve transcriptional factor nuclear factor-kappaB (NF-kappaB) pathway. ET(B) recepto...

  8. Transcriptional regulation by competing transcription factor modules.

    Directory of Open Access Journals (Sweden)

    Rutger Hermsen

    2006-12-01

    Full Text Available Gene regulatory networks lie at the heart of cellular computation. In these networks, intracellular and extracellular signals are integrated by transcription factors, which control the expression of transcription units by binding to cis-regulatory regions on the DNA. The designs of both eukaryotic and prokaryotic cis-regulatory regions are usually highly complex. They frequently consist of both repetitive and overlapping transcription factor binding sites. To unravel the design principles of these promoter architectures, we have designed in silico prokaryotic transcriptional logic gates with predefined input-output relations using an evolutionary algorithm. The resulting cis-regulatory designs are often composed of modules that consist of tandem arrays of binding sites to which the transcription factors bind cooperatively. Moreover, these modules often overlap with each other, leading to competition between them. Our analysis thus identifies a new signal integration motif that is based upon the interplay between intramodular cooperativity and intermodular competition. We show that this signal integration mechanism drastically enhances the capacity of cis-regulatory domains to integrate signals. Our results provide a possible explanation for the complexity of promoter architectures and could be used for the rational design of synthetic gene circuits.

  9. Endocytosis-independent function of clathrin heavy chain in the control of basal NF-κB activation.

    Directory of Open Access Journals (Sweden)

    Man Lyang Kim

    Full Text Available BACKGROUND: Nuclear factor-κB (NF-κB is a transcription factor that regulates the transcription of genes involved in a variety of biological processes, including innate and adaptive immunity, stress responses and cell proliferation. Constitutive or excessive NF-κB activity has been associated with inflammatory disorders and higher risk of cancer. In contrast to the mechanisms controlling inducible activation, the regulation of basal NF-κB activation is not well understood. Here we test whether clathrin heavy chain (CHC contributes to the regulation of basal NF-κB activity in epithelial cells. METHODOLOGY: Using RNA interference to reduce endogenous CHC expression, we found that CHC is required to prevent constitutive activation of NF-κB and gene expression. Immunofluorescence staining showed constitutive nuclear localization of the NF-κB subunit p65 in absence of stimulation after CHC knockdown. Elevated basal p65 nuclear localization is caused by constitutive phosphorylation and degradation of inhibitor of NF-κB alpha (IκBα through an IκB kinase α (IKKα-dependent mechanism. The role of CHC in NF-κB signaling is functionally relevant as constitutive expression of the proinflammatory chemokine interleukin-8 (IL-8, whose expression is regulated by NF-κB, was found after CHC knockdown. Disruption of clathrin-mediated endocytosis by chemical inhibition or depletion of the μ2-subunit of the endocytosis adaptor protein AP-2, and knockdown of clathrin light chain a (CHLa, failed to induce constitutive NF-κB activation and IL-8 expression, showing that CHC acts on NF-κB independently of endocytosis and CLCa. CONCLUSIONS: We conclude that CHC functions as a built-in molecular brake that ensures a tight control of basal NF-κB activation and gene expression in unstimulated cells. Furthermore, our data suggest a potential link between a defect in CHC expression and chronic inflammation disorder and cancer.

  10. Aspirin Prevention of Colorectal Cancer: Focus on NF-κB Signalling and the Nucleolus

    Directory of Open Access Journals (Sweden)

    Jingyu Chen

    2017-07-01

    Full Text Available Overwhelming evidence indicates that aspirin and related non-steroidal anti-inflammatory drugs (NSAIDs have anti-tumour activity and the potential to prevent cancer, particularly colorectal cancer. However, the mechanisms underlying this effect remain hypothetical. Dysregulation of the nuclear factor-kappaB (NF-κB transcription factor is a common event in many cancer types which contributes to tumour initiation and progression by driving expression of pro-proliferative/anti-apoptotic genes. In this review, we will focus on the current knowledge regarding NSAID effects on the NF-κB signalling pathway in pre-cancerous and cancerous lesions, and the evidence that these effects contribute to the anti-tumour activity of the agents. The nuclear organelle, the nucleolus, is emerging as a central regulator of transcription factor activity and cell growth and death. Nucleolar function is dysregulated in the majority of cancers which promotes cancer growth through direct and indirect mechanisms. Hence, this organelle is emerging as a promising target for novel therapeutic agents. Here, we will also discuss evidence for crosstalk between the NF-κB pathway and nucleoli, the role that this cross-talk has in the anti-tumour effects of NSAIDs and ways forward to exploit this crosstalk for therapeutic purpose.

  11. Regulation of stem cell factor expression in inflammation and asthma

    Directory of Open Access Journals (Sweden)

    Carla A Da Silva

    2005-03-01

    Full Text Available Stem cell factor (SCF is a major mast cell growth factor, which could be involved in the local increase of mast cell number in the asthmatic airways. In vivo, SCF expression increases in asthmatic patients and this is reversed after treatment with glucocorticoids. In vitro in human lung fibroblasts in culture, IL-1beta, a pro-inflammatory cytokine, confirms this increased SCF mRNA and protein expression implying the MAP kinases p38 and ERK1/2 very early post-treatment, and glucocorticoids confirm this decrease. Surprisingly, glucocorticoids potentiate the IL-1beta-enhanced SCF expression at short term treatment, implying increased SCF mRNA stability and SCF gene transcription rate. This potentiation involves p38 and ERK1/2. Transfection experiments with the SCF promoter including intron1 also confirm this increase and decrease of SCF expression by IL-1beta and glucocorticoids, and the potentiation by glucocorticoids of the IL-1beta-induced SCF expression. Deletion of the GRE or kappaB sites abolishes this potentiation, and the effect of IL-1beta or glucocorticoids alone. DNA binding of GR and NF-kappaB are also demonstrated for these effects. In conclusion, this review concerns new mechanisms of regulation of SCF expression in inflammation that could lead to potential therapeutic strategy allowing to control mast cell number in the asthmatic airways.

  12. Nano-gold displayed anti-inflammatory property via NF-kB pathways by suppressing COX-2 activity.

    Science.gov (United States)

    Khan, Mahmood Ahmad; Khan, Mohd Jahir

    2018-03-19

    Rheumatoid arthritis (RA) is an autoimmune inflammatory disease, affecting almost 1% of world population. Although the exact cause of RA is not known but the complex interaction between inflammatory mediators like tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and nitric oxide (NO) is accountable for cartilage destruction in joints. Gold is used for arthritis treatment since long without knowing its mechanism of action. Hence, the present study was designed to assess antiarthritic activity of nanogold (AuNGs) in collagen-induced arthritic (CIA) rat model by virtue of decreasing inflammatory mediators and oxidative stress. After induction CIA rats were treated with AuNGs in phosphate buffer at a dose of 20 μg/kg body weight for 20 days and found a significant decrease in the level of inflammatory mediators like TNF-α, IL-1β, COX-2 and transcription factor NF-kB (Nuclear factor-kB), which was found to be elevated in CIA rats. Additionally imbalance in oxidant and antioxidant status were determined and perceived that AuNGs remarkably attenuates the imbalance in level of antioxidant and oxidant near to normal. In consistent to biochemical results, mRNA expression of NF-kB, TNF-α, COX-2, and iNOS were also up-regulated in CIA rats, which were considerably down regulated by AuNGs treatment. These findings were positively correlated with the histological results of joints, displayed reduced inflammation and bone erosion in treated group. This study demonstrates the ability of AuNGs to ameliorate production of inflammatory mediators and oxidative stress in CIA rats. Induction of arthritis in rats showed increased inflammation, which activate the transcription factor NF-kB through activation of of IkB kinases (IKK) and ubiquination/proteosome degradation of IKB and transportation of activated NF-kB from cytoplasm to nucleus. In nucleus activated NF-kB bind to the promoter region of target gene and up regulate the production of

  13. Targeting Endothelial Adhesion Molecule Transcription for Treatment of Inflammatory Disease: A Proof-of-Concept Study

    Directory of Open Access Journals (Sweden)

    Liam M. Ashander

    2016-01-01

    Full Text Available Targeting the endothelial adhesion molecules that control leukocyte trafficking into a tissue has been explored as a biological therapy for inflammatory diseases. However, these molecules also participate in leukocyte migration for immune surveillance, and inhibiting the physiological level of an adhesion molecule might promote infection or malignancy. We explored the concept of targeting endothelial adhesion molecule transcription during inflammation in a human system. Intercellular adhesion molecule 1 (ICAM-1 mediates leukocyte migration across the retinal endothelium in noninfectious posterior uveitis. We observed an increase in the transcription factor, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NF-κB1, in parallel with ICAM-1, in human retinal endothelial cells treated with tumor necrosis factor-alpha (TNF-α, and identified putative binding sites for NF-κB1 within the ICAM-1 regulatory region. We targeted induced NF-κB1 expression in endothelial cells with small interfering (siRNA. Knockdown of NF-κB1 significantly decreased cell surface expression of ICAM-1 protein induced by TNF-α but did not reduce constitutive ICAM-1 expression. Consistently, NF-κB1 knockdown significantly reduced leukocyte binding to cell monolayers in the presence of TNF-α but did not impact baseline binding. Findings of this proof-of-concept study indicate that induced transcription of endothelial adhesion molecules might be targeted therapeutically for inflammatory disease in humans.

  14. Control of NF-kB activity in human melanoma by bromodomain and extra-terminal protein inhibitor I-BET151.

    Science.gov (United States)

    Gallagher, Stuart J; Mijatov, Branka; Gunatilake, Dilini; Gowrishankar, Kavitha; Tiffen, Jessamy; James, Wilmott; Jin, Lei; Pupo, Gulietta; Cullinane, Carleen; McArthur, Grant A; Tummino, Peter J; Rizos, Helen; Hersey, Peter

    2014-11-01

    The transcription factor NF-kappaB (NF-kB) is a key regulator of cytokine and chemokine production in melanoma and is responsible for symptoms such as anorexia, fatigue, and weight loss. In addition, NF-kB is believed to contribute to progression of the disease by upregulation of cell cycle and anti-apoptotic genes and to contribute to resistance against targeted therapies and immunotherapy. In this study, we have examined the ability of the bromodomain and extra-terminal (BET) protein inhibitor I-BET151 to inhibit NF-kB in melanoma cells. We show that I-BET151 is a potent, selective inhibitor of a number of NF-kB target genes involved in induction of inflammation and cell cycle regulation and downregulates production of cytokines such as IL-6 and IL-8. SiRNA studies indicate that BRD2 is the main BET protein involved in regulation of NF-kB and that I-BET151 caused transcriptional downregulation of the NF-kB subunit p105/p50. These results suggest that BET inhibitors may have an important role in treatment of melanoma where activation of NF-kB may have a key pathogenic role. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. The Journey of a Transcription Factor

    DEFF Research Database (Denmark)

    Pireyre, Marie

    Plants have developed astonishing networks regulating their metabolism to adapt to their environment. The complexity of these networks is illustrated by the expansion of families of regulators such as transcription factors in the plant kingdom. Transcription factors specifically impact...... transcriptional networks by integrating exogenous and endogenous stimuli and regulating gene expression accordingly. Regulation of transcription factors and their activation is thus highly important to modulate the transcriptional programs and increase fitness of the plant in a given environment. Plant metabolism....... The biosynthetic machinery of GLS is governed by interplay of six MYB and three bHLH transcription factors. MYB28, MYB29 and MYB76 regulate methionine-derived GLS, and MYB51, MYB34 and MYB122 regulate tryptophan-derived GLS. The three bHLH transcription factors MYC2, MYC3 and MYC4 physically interact with all six...

  16. RPAP3 enhances cytotoxicity of doxorubicin by impairing NF-kappa B pathway

    International Nuclear Information System (INIS)

    Shimada, Kana; Saeki, Makio; Egusa, Hiroshi; Fukuyasu, Sho; Yura, Yoshiaki; Iwai, Kazuhiro; Kamisaki, Yoshinori

    2011-01-01

    Research highlights: → RNA polymerase II-associated protein 3 (RPAP3) possesses an activity to bind with NEMO and to inhibit the ubiquitination of NEMO. → RPAP3 enhances doxorubicin-induced cell death in breast cancer cell line T-47D through the marked impairment of NF-κB pathway. → RPAP3 is a novel modulator of NF-κB pathway in apoptosis induced by anti-cancer chemotherapeutic agents. -- Abstract: Activation of anti-apoptotic gene transcription by NF-κB (nuclear factor-kappa B) has been reported to be linked with a resistance of cancer cells against chemotherapy. NEMO (NF-κB essential modulator) interacts with a number of proteins and modulates the activity of NF-κB pathway. In this study, we revealed that RPAP3 (RNA polymerase II-associated protein 3) possesses an activity to bind with NEMO and to inhibit the ubiquitination of NEMO and that RPAP3 enhances doxorubicin-induced cell death in breast cancer cell line T-47D through the marked impairment of NF-κB pathway. These results indicate that RPAP3 may be a novel modulator of NF-κB pathway in apoptosis induced by anti-cancer chemotherapeutic agents.

  17. Helicobacter pylori VacA enhances prostaglandin E2 production through induction of cyclooxygenase 2 expression via a p38 mitogen-activated protein kinase/activating transcription factor 2 cascade in AZ-521 cells

    DEFF Research Database (Denmark)

    Hisatsune, Junzo; Yamasaki, Eiki; Nakayama, Masaaki

    2007-01-01

    of a COX-2 promoter reporter gene and activated a COX-2 promoter containing mutated NF-kappaB or NF-interleukin-6 sites but not a mutated cis-acting replication element (CRE) site, suggesting direct involvement of the activating transcription factor 2 (ATF-2)/CREB-binding region in VacA-induced COX-2...... to activation of the CRE site in the COX-2 promoter....

  18. Targeting loss of the Hippo signaling pathway in NF2-deficient papillary kidney cancers

    Science.gov (United States)

    Ricketts, Christopher J.; Wei, Darmood; Yang, Youfeng; Baranes, Sarah M.; Gibbs, Benjamin K.; Ohanjanian, Lernik; Spencer Krane, L.; Scroggins, Bradley T.; Keith Killian, J.; Wei, Ming-Hui; Kijima, Toshiki; Meltzer, Paul S.; Citrin, Deborah E.; Neckers, Len; Vocke, Cathy D.; Marston Linehan, W.

    2018-01-01

    Papillary renal cell carcinomas (PRCC) are a histologically and genetically heterogeneous group of tumors that represent 15–20% of all kidney neoplasms and may require diverse therapeutic approaches. Alteration of the NF2 tumor suppressor gene, encoding a key regulator of the Hippo signaling pathway, is observed in 22.5% of PRCC. The Hippo signaling pathway controls cell proliferation by regulating the transcriptional activity of Yes-Associated Protein, YAP1. Loss of NF2 results in aberrant YAP1 activation. The Src family kinase member Yes also regulates YAP1 transcriptional activity. This study investigated the importance of YAP and Yes activity in three NF2-deficient PRCC cell lines. NF2-deficency correlated with increased expression of YAP1 transcriptional targets and siRNA-based knockdown of YAP1 and Yes1 downregulated this pathway and dramatically reduced cell viability. Dasatinib and saracatinib have potent inhibitory effects on Yes and treatment with either resulted in downregulation of YAP1 transcription targets, reduced cell viability, and G0-G1 cell cycle arrest. Xenograft models for NF2-deficient PRCC also demonstrated reduced tumor growth in response to dasatinib. Thus, inhibiting Yes and the subsequent transcriptional activity of YAP1 had a substantial anti-tumor cell effect both in vitro and in vivo and may provide a viable therapeutic approach for patients with NF2-deficient PRCC. PMID:29535838

  19. Cytokine regulation of pro- and anti-apoptotic genes in rat hepatocytes: NF-kappaB-regulated inhibitor of apoptosis protein 2 (cIAP2) prevents apoptosis

    NARCIS (Netherlands)

    Schoemaker, Marieke H.; Ros, Jenny E.; Homan, Manon; Trautwein, Christian; Liston, Peter; Poelstra, Klaas; van Goor, Harry; Jansen, Peter L. M.; Moshage, Han

    2002-01-01

    BACKGROUND/AIMS: In acute liver failure, hepatocytes are exposed to various cytokines that activate both cell survival and apoptotic pathways. NF-kappaB is a central transcription factor in these responses. Recent studies indicate that blocking NF-kappaB causes apoptosis, indicating the existence of

  20. Depletion of the cellular levels of Bag-1 proteins attenuates phorbol ester-induced downregulation of IκBα and nuclear accumulation of NF-κB

    International Nuclear Information System (INIS)

    Maier, Jana V.; Volz, Yvonne; Berger, Caroline; Schneider, Sandra; Cato, Andrew C.B.

    2010-01-01

    Research highlights: →Bag-1 depletion only marginally affects the action of the glucocorticoid receptor but strongly regulates the activity of NF-κB. →Bag-1 depletion attenuates phosphorylation and degradation of IκBα and nuclear accumulation of NF-κB p65 and p50. →Bag-1 interacts with IκBα and partially restores IκBα and NF-κB activation in Bag-1 depleted cells. -- Abstract: Bag-1 consists in humans of four isoforms generated from the same RNA by alternative translation. Overexpression of single Bag-1 isoforms has identified Bag-1 as a negative regulator of action of many proteins including the glucocorticoid receptor (GR). Here we have analysed the ability of Bag-1 to regulate the transrepression function of the GR. Silencing Bag-1 expression only marginally affects the transrepression action of the GR but decreased the action of the transcription factor NF-κB. Furthermore phosphorylation and degradation of the inhibitor protein IκBα and nuclear accumulation of p65 and p50 NF-κB proteins in response to phorbol ester was attenuated following Bag-1 depletion in HeLa cells. Reconstitution of Bag-1 in depleted cells partially restored IκBα and NF-κB activation. Knock-down of Bag-1 expression also did not significantly alter GR-mediated transactivation but affected the basal transcription of some of the target genes. Thus Bag-1 proteins function as regulators of the action of selective transcription factors.

  1. NF-kappa B activity in T cells stably expressing the Tax protein of human T cell lymphotropic virus type I

    International Nuclear Information System (INIS)

    Lacoste, J.; Cohen, L.; Hiscott, J.

    1991-01-01

    The effect of constitutive Tax expression on the interaction of NF-κ B with its recognition sequence and on NF-κ B-dependent gene expression was examined in T lymphoid Jurkat cell lines (19D and 9J) stably transformed with a Tax expression vector. Tax expressing T cell lines contained a constitutive level of NF-κ B binding activity, detectable by mobility shift assay and uv cross-linking using a palindromic NF-κ B probe homologous to the interferon beta PRDII site. In Jurkat and NC2.10 induction with phorbol esters resulted in the appearance of new DNA binding proteins of 85, 75, and 54 kDa, whereas in Tax expressing cells the 85-kDa protein and a 92-kDa DNA binding protein were constitutively induced. Expression of Tax protein in 19D and 9J resulted in transcription of the endogenous NF-kappa B-dependent granulocyte-macrophage colony stimulating factor gene and increased basal level expression of transfected NF-kappa B-regulated promoters. Nonetheless transcription of both the endogenous and the transfected gene was inducible by PMA treatment. Tax expression in Jurkat T cells may alter the stoichiometry of NF-kappa B DNA binding proteins and thus change the expression of NF-kappa B-regulated promoters

  2. Extracellular histones induce tissue factor expression in vascular endothelial cells via TLR and activation of NF-κB and AP-1.

    Science.gov (United States)

    Yang, Xinyu; Li, Lin; Liu, Jin; Lv, Ben; Chen, Fangping

    2016-01-01

    Extracellular histones have been recognized recently as proinflammatory mediators; they are released from dying cells in response to inflammatory challenge, contributing to endothelial cell dysfunction, thrombin formation, organ failure, and death during sepsis. Clinical studies suggest that the plasma concentration of the histone-DNA complex is correlated with the severity of DIC and is a poor independent prognostic marker in sepsis. In addition, platelet activation stimulates thrombus formation. Whether histones contribute to procoagulant activity in other ways remains elusive. In this study, we confirmed that histones induce tissue factor (TF) expression in a concentration- and time-dependent manner in vascular endothelial cells (ECs) and macrophages. However, histones did not affect TF pathway inhibitor expression. Moreover, blocking the cell surface receptors TLR4 and TLR2 with specific neutralizing antibodies significantly reduced histone-induced TF expression. Furthermore, histones enhanced the nuclear translocation of NF-κB (c-Rel/p65) and AP-1 expression in a time-dependent manner in ECs. Mutating NF-κB and AP-1 significantly reduced histone-induced TF expression. Altogether, our experiments suggest that histone induces TF expression in ECs via cell surface receptors TLR4 and TLR2, simultaneously depending on the activation of the transcription factors NF-κB and AP-1. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Obesity-induced endoplasmic reticulum stress suppresses nuclear factor-Y expression.

    Science.gov (United States)

    Liu, Yulan; Zhang, Yuwei; Zhang, Yanjie; Zhang, Jinlong; Liu, Yin; Feng, Peiqun; Su, Zhiguang

    2017-02-01

    Nuclear transcription factor Y (NF-Y) is an evolutionarily conserved transcription factor composed of three subunits, NF-YA, NF-YB, and NF-YC. NF-Y plays crucial roles in pre-adipocyte maintenance and/or commitment to adipogenesis. NF-YA dysfunction in adipocyte resulted in an age-dependent progressive loss of adipose tissue associated with metabolic complications. Endoplasmic reticulum (ER) stress has emerged as an important mediator in the pathogenesis of obesity. However, it is not known if NF-YA is involved in the ER stress-mediated pathogenesis of obesity. We first examined the effects of ER stress on the NF-YA expression in cultured 3T3-L1 adipocytes; then in ob/ob genetic obesity mice, we tested the effect of chemical chaperones alleviating ER stress on the expression levels of NF-YA. Subsequently, we inhibited the new mRNA synthesis using actinomycin D in 3T3-L1 cells to explore the mechanism modulating NF-YA expression. Finally, we evaluated the involvement of PPARg in the regulation of NF-YA expression by ER stress. We demonstrated that both obesity- and chemical chaperone -induced ER stress suppressed NF-YA expression and alleviation of ER stress by chemical chaperone could recover NF-YA expression in ob/ob mice. Moreover, we showed that ER stress suppressed NF-YA mRNA transcription through the involvement of peroxisome proliferator-activated receptor gamma (PPARg). Activation of PPARg ameliorates the ER stress-induced NF-YA suppression. Our findings may point to a possible role of NF-YA in stress conditions that occur in chronic obesity, ER stress might be involved in the pathogenesis of obesity through NF-YA depletion.

  4. NF-κB p65 Subunit Is Modulated by Latent Transforming Growth Factor-β Binding Protein 2 (LTBP2 in Nasopharyngeal Carcinoma HONE1 and HK1 Cells.

    Directory of Open Access Journals (Sweden)

    Rebecca Kan

    Full Text Available NF-κB is a well-characterized transcription factor, widely known as a key player in tumor-derived inflammation and cancer development. Herein, we present the functional and molecular relevance of the canonical NF-κB p65 subunit in nasopharyngeal carcinoma (NPC. Loss- and gain-of-function approaches were utilized to reveal the functional characteristics of p65 in propagating tumor growth, tumor-associated angiogenesis, and epithelial-to-mesenchymal transition in NPC cells. Extracellular inflammatory stimuli are critical factors that trigger the NF-κB p65 signaling; hence, we investigated the components of the tumor microenvironment that might potentially influence the p65 signaling pathway. This led to the identification of an extracellular matrix (ECM protein that was previously reported as a candidate tumor suppressor in NPC. Our studies on the Latent Transforming Growth Factor-β Binding Protein 2 (LTBP2 protein provides substantial evidence that it can modulate the p65 transcriptional activity. Re-expression of LTBP2 elicits tumor suppressive effects that parallel the inactivation of p65 in NPC cells. LTBP2 was able to reduce phosphorylation of p65 at Serine 536, inhibit nuclear localization of active phosphorylated p65, and impair the p65 DNA-binding ability. This results in a consequential down-regulation of p65-related gene expression. Therefore, the data suggest that the overall up-regulation of p65 expression and the loss of this candidate ECM tumor suppressor are milestone events contributing to NPC development.

  5. Inhibition of NF-κB in Tumor Cells Exacerbates Immune Cell Activation Following Photodynamic Therapy

    Science.gov (United States)

    Broekgaarden, Mans; Kos, Milan; Jurg, Freek A.; van Beek, Adriaan A.; van Gulik, Thomas M.; Heger, Michal

    2015-01-01

    Although photodynamic therapy (PDT) yields very good outcomes in numerous types of superficial solid cancers, some tumors respond suboptimally to PDT. Novel treatment strategies are therefore needed to enhance the efficacy in these therapy-resistant tumors. One of these strategies is to combine PDT with inhibitors of PDT-induced survival pathways. In this respect, the transcription factor nuclear factor κB (NF-κB) has been identified as a potential pharmacological target, albeit inhibition of NF-κB may concurrently dampen the subsequent anti-tumor immune response required for complete tumor eradication and abscopal effects. In contrast to these postulations, this study demonstrated that siRNA knockdown of NF-κB in murine breast carcinoma (EMT-6) cells increased survival signaling in these cells and exacerbated the inflammatory response in murine RAW 264.7 macrophages. These results suggest a pro-death and immunosuppressive role of NF-κB in PDT-treated cells that concurs with a hyperstimulated immune response in innate immune cells. PMID:26307977

  6. UPP mediated Diabetic Retinopathy via ROS/PARP and NF-κB inflammatory factor pathways.

    Science.gov (United States)

    Luo, D-W; Zheng, Z; Wang, H; Fan, Y; Chen, F; Sun, Y; Wang, W-J; Sun, T; Xu, X

    2015-01-01

    Diabetic retinopathy (DR) is a leading cause of blindness in adults at working age. Human diabetic retinopathy is characterized by the basement membrane thick, pericytes loss, microaneurysms formation, retina neovascularization and vitreous hemorrhage. To investigate whether UPP activated ROS/PARP and NF-κB inflammatory factor pathways in Diabetic Retinopathy, human retinal endothelial cells (HRECs) and rats with streptozotocin-induced diabetes were used to determine the effect of UPP on ROS generation, cell apoptosis, mitochondrial membrane potential (ΔΨm) and inflammatory factor protein expression, through flow cytometry assay, immunohistochemistry, Real-time PCR, Western blot analysis and ELISA. The levels of ROS and apoptosis and the expressions of UPP (Ub and E3) and inflammatory factor protein were increased in high glucose-induced HRECs and retina of diabetic rats, while ΔΨm was decreased. The UPP inhibitor and UbshRNA could attenuate these effects through inhibiting the pathway of ROS/PARP and the expression of NF-κB inflammatory factors, and the increased UPP was a result of high glucose-induced increase of ROS generation and NF-κBp65 expression, accompanied with the decrease of ΔΨm. Clinical study showed the overexpression of UPP and detachment of epiretinal membranes in proliferative DR (PDR) patients. It has been indicated that the pathogenic effect of UPP on DR was involved in the increase of ROS generation and NF-κB expression, which associated with the ROS/PARP and NF-κB inflammatory factor pathways. Our study supports a new insight for further application of UPP inhibitor in DR treatment.

  7. Interrogation of inhibitor of nuclear factor κB α/nuclear factor κB (IκBα/NF-κB) negative feedback loop dynamics: from single cells to live animals in vivo.

    Science.gov (United States)

    Moss, Britney L; Elhammali, Adnan; Fowlkes, Tiffanie; Gross, Shimon; Vinjamoori, Anant; Contag, Christopher H; Piwnica-Worms, David

    2012-09-07

    Full understanding of the biological significance of negative feedback processes requires interrogation at multiple scales as follows: in single cells, cell populations, and live animals in vivo. The transcriptionally coupled IκBα/NF-κB negative feedback loop, a pivotal regulatory node of innate immunity and inflammation, represents a model system for multiscalar reporters. Using a κB(5)→IκBα-FLuc bioluminescent reporter, we rigorously evaluated the dynamics of ΙκBα degradation and subsequent NF-κB transcriptional activity in response to diverse modes of TNFα stimulation. Modulating TNFα concentration or pulse duration yielded complex, reproducible, and differential ΙκBα dynamics in both cell populations and live single cells. Tremendous heterogeneity in the transcriptional amplitudes of individual responding cells was observed, which was greater than the heterogeneity in the transcriptional kinetics of responsive cells. Furthermore, administration of various TNFα doses in vivo generated ΙκBα dynamic profiles in the liver resembling those observed in single cells and populations of cells stimulated with TNFα pulses. This suggested that dose modulation of circulating TNFα was perceived by hepatocytes in vivo as pulses of increasing duration. Thus, a robust bioluminescent reporter strategy enabled rigorous quantitation of NF-κB/ΙκBα dynamics in both live single cells and cell populations and furthermore, revealed reproducible behaviors that informed interpretation of in vivo studies.

  8. Proinflammatory cytokine tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) suppresses satellite cell self-renewal through inversely modulating Notch and NF-κB signaling pathways.

    Science.gov (United States)

    Ogura, Yuji; Mishra, Vivek; Hindi, Sajedah M; Kuang, Shihuan; Kumar, Ashok

    2013-12-06

    Satellite cell self-renewal is an essential process to maintaining the robustness of skeletal muscle regenerative capacity. However, extrinsic factors that regulate self-renewal of satellite cells are not well understood. Here, we demonstrate that TWEAK cytokine reduces the proportion of Pax7(+)/MyoD(-) cells (an index of self-renewal) on myofiber explants and represses multiple components of Notch signaling in satellite cell cultures. The number of Pax7(+) cells is significantly increased in skeletal muscle of TWEAK knock-out (KO) mice compared with wild-type in response to injury. Furthermore, Notch signaling is significantly elevated in cultured satellite cells and in regenerating myofibers of TWEAK-KO mice. Forced activation of Notch signaling through overexpression of the Notch1 intracellular domain (N1ICD) rescued the TWEAK-mediated inhibition of satellite cell self-renewal. TWEAK also activates the NF-κB transcription factor in satellite cells and inhibition of NF-κB significantly improved the number of Pax7(+) cells in TWEAK-treated cultures. Furthermore, our results demonstrate that a reciprocal interaction between NF-κB and Notch signaling governs the inhibitory effect of TWEAK on satellite cell self-renewal. Collectively, our study demonstrates that TWEAK suppresses satellite cell self-renewal through activating NF-κB and repressing Notch signaling.

  9. NF-kappaB specifically activates BMP-2 gene expression in growth plate chondrocytes in vivo and in a chondrocyte cell line in vitro.

    Science.gov (United States)

    Feng, Jian Q; Xing, Lianping; Zhang, Jiang-Hong; Zhao, Ming; Horn, Diane; Chan, Jeannie; Boyce, Brendan F; Harris, Stephen E; Mundy, Gregory R; Chen, Di

    2003-08-01

    Bone morphogenetic protein-2 (BMP-2) regulates growth plate chondrogenesis during development and postnatal bone growth, but the control mechanisms of BMP-2 expression in growth plate chondrocytes are unknown. Here we have used both in vitro and in vivo approaches to demonstrate that transcription factor, NF-kappaB, regulates BMP-2 gene expression in chondrocytes. Two putative NF-kappaB response elements were found in the -2712/+165 region of the BMP-2 gene. Cotransfection of mutant I-kappaBalpha expression plasmids with BMP-2 promoter-luciferase reporters into TMC-23 chondrocyte cell line suppressed BMP-2 transcription. Mutations in NF-kappaB response elements in the BMP-2 gene lead to decreases in BMP-2 promoter activity. Electrophoretic mobility shift assay using nuclear extracts from TMC-23 chondrocytic cells revealed that the NF-kappaB subunits p50 and p65 bound to the NF-kappaB response elements of the BMP-2 gene. Thus, NF-kappaB may positively regulate BMP-2 gene transcription. Consistent with these findings, expression of BMP-2 mRNA was significantly reduced in growth plate chondrocytes in NF-kappaB p50/p52 dKO mice, which associated with decreased numbers of 5-bromo-2'-deoxyuridine (BrdUrd)-positive cells in the proliferating zone of growth plate in these mice. Therefore, in postnatal growth plate chondrocytes, expression of BMP-2 is regulated by NF-kappaB, which may play an important role in chondrogenesis.

  10. Sustained NF-κB activation and inhibition in β-cells have minimal effects on function and islet transplant outcomes.

    Directory of Open Access Journals (Sweden)

    Aileen J F King

    Full Text Available The activation of the transcription factor NF-κB leads to changes in expression of many genes in pancreatic β-cells. However, the role of NF-κB activation in islet transplantation has not been fully elucidated. The aim of the present study was to investigate whether the state of NF-κB activation would influence the outcome of islet transplantation. Transgenic mice expressing a dominant active IKKβ (constitutively active or a non-degradable form of IκBα (constitutive inhibition under control of the rat insulin promoter were generated. Islets from these mice were transplanted into streptozotocin diabetic mice in suboptimal numbers. Further, the effects of salicylate (an inhibitor of NF-κB treatment of normal islets prior to transplantation, and the effects of salicylate administration to mice prior to and after islet implantation were evaluated. Transplantation outcomes were not affected using islets expressing a non-degradable form of IκBα when compared to wild type controls. However, the transplantation outcomes using islets isolated from mice expressing a constitutively active mutant of NF-κB were marginally worse, although no aberrations of islet function in vitro could be detected. Salicylate treatment of normal islets or mice had no effect on transplantation outcome. The current study draws attention to the complexities of NF-κB in pancreatic beta cells by suggesting that they can adapt with normal or near normal function to both chronic activation and inhibition of this important transcription factor.

  11. Gene structure, expression pattern and interaction of Nuclear Factor-Y family in castor bean (Ricinus communis).

    Science.gov (United States)

    Wang, Yue; Xu, Wei; Chen, Zexi; Han, Bing; Haque, Mohammad E; Liu, Aizhong

    2018-03-01

    Nuclear Factor-Y transcription factors, which function in regulating seed development (including storage reservoir accumulation) and responding to abiotic stresses, were identified and characterized in castor bean. Nuclear Factor-Y (NF-Y) transcription factors in plants contain three subunits (NF-YA, NF-YB and NF-YC), and function as a heterodimer or heterotrimer complex in regulating plant growth, development and response to stresses. Castor bean (Ricinus communis, Euphorbiaceae) one of the most economically important non-edible oilseed crops, able to grow in diverse soil conditions and displays high tolerance to abiotic stresses. Due to increasing demands for its seed oils, it is necessary to elucidate the molecular mechanism underlying the regulation of growth and development. Based on the available genome data, we identified 25 RcNF-Y members including six RcNF-YAs, 12 RcNF-YBs and seven RcNF-YCs, and characterized their gene structures. Yeast two-hybrid assays confirmed the protein-protein interactions among three subunits. Using transcriptomic data from different tissues, we found that six members were highly or specifically expressed in endosperms (in particular, two LEC1-type members RcNF-YB2 and RcNF-YB12), implying their involvement in regulating seed development and storage reservoir accumulation. Further, we investigated the expression changes of RcNF-Y members in two-week-old seedlings under drought, cold, hot and salt stresses. We found that the expression levels of 20 RcNF-Y members tested were changed and three RcNF-Y members might function in response to abiotic stresses. This study is the first reported on genomic characterization of NF-Y transcription factors in the family Euphorbiaceae. Our results provide the basis for improved understanding of how NF-Y genes function in the regulation of seed development and responses to abiotic stresses in both castor bean and other plants in this family.

  12. Assessment of hypoxia and TNF-alpha response by a vector with HRE and NF-kappaB response elements.

    Science.gov (United States)

    Chen, Zhilin; Eadie, Ashley L; Hall, Sean R; Ballantyne, Laurel; Ademidun, David; Tse, M Yat; Pang, Stephen C; Melo, Luis G; Ward, Christopher A; Brunt, Keith R

    2017-01-01

    Hypoxia and inflammatory cytokine activation (H&I) are common processes in many acute and chronic diseases. Thus, a single vector that responds to both hypoxia and inflammatory cytokines, such as TNF-alpha, is useful for assesing the severity of such diseases. Adaptation to hypoxia is regulated primarily by hypoxia inducible transcription factor (HIF alpha) nuclear proteins that engage genes containing a hypoxia response element (HRE). Inflammation activates a multitude of cytokines, including TNF-alpha, that invariably modulate activation of the nuclear factor kappa B (NF-kB) transcription factor. We constructed a vector that encompassed both a hypoxia response element (HRE), and a NF-kappaB responsive element. We show that this vector was functionally responsive to both hypoxia and TNF-alpha, in vitro and in vivo . Thus, this vector might be suitable for the detection and assessment of hypoxia or TNF-alpha.

  13. Danshen attenuates osteoarthritis-related cartilage degeneration through inhibition of NF-κB signaling pathway in vivo and in vitro.

    Science.gov (United States)

    Xu, Xilin; Lv, Hang; Li, Xiaodong; Su, Hui; Zhang, Xiaofeng; Yang, Jun

    2017-12-01

    Danshen (Salvia miltiorrhiza) is a traditional Chinese medicine herb that can alleviate the symptoms of osteoarthritis (OA) (Söder et al. 2006) in animals. However, the underlying mechanisms remain poorly understood and require further investigation. In this study, rabbits with experimentally induced OA were given an intra-articular injection of danshen (0.7 mL/day) for 5 weeks. In addition to attenuating the cartilage degeneration of OA in the rabbits, danshen decreased the expression and activity of matrix metalloproteinase 9 (MMP-9) and MMP-13, and increased the expression of their natural inhibitors: tissue inhibitor of matrix metalloproteinase 1 (TIMP-1) and TIMP-2. Apoptosis in osteoarthritic cartilage tissues was attenuated by danshen, accompanied with increased expression of B cell lymphoma 2 (Bcl-2) and decreased levels of Bcl-2-associated X protein (Bax). Further, danshen inhibited the nuclear accumulation of nuclear factor kappa-B (NF-κB) p65 in osteoarthritic cartilage. The therapeutic effects of danshen in vivo were comparable to that of sodium hyaluronate, which is a drug used clinically for the treatment OA. In vitro, sodium nitroprusside (SNP) was used to stimulate apoptosis in primary rabbit chondrocytes. We found that the SNP-induced apoptosis was mitigated by danshen. BAY11-7028, an inhibitor of the NF-κB pathway, augmented danshen's anti-apoptotic effects in cells exposed to SNP. When these results are considered together, they indicate that danshen alleviates the cartilage injury in rabbit OA through inhibition of the NF-κB signaling pathway.

  14. NF-κB regulation of endothelial cell function during LPS-induced toxemia and cancer

    Science.gov (United States)

    Kisseleva, Tatiana; Song, Li; Vorontchikhina, Marina; Feirt, Nikki; Kitajewski, Jan; Schindler, Christian

    2006-01-01

    The transcription factor NF-κB is an important regulator of homeostatic growth and inflammation. Although gene-targeting studies have revealed important roles for NF-κB, they have been complicated by component redundancy and lethal phenotypes. To examine the role of NF-κB in endothelial tissues, Tie2 promoter/enhancer–IκBαS32A/S36A transgenic mice were generated. These mice grew normally but exhibited enhanced sensitivity to LPS-induced toxemia, notable for an increase in vascular permeability and apoptosis. Moreover, B16-BL6 tumors grew significantly more aggressively in transgenic mice, underscoring a new role for NF-κB in the homeostatic response to cancer. Tumor vasculature in transgenic mice was extensive and disorganized. This correlated with a marked loss in tight junction formation and suggests that NF-κB plays an important role in the maintenance of vascular integrity and response to stress. PMID:17053836

  15. Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

    Science.gov (United States)

    Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

    2012-01-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

  16. Activating transcription factor 3 regulates immune and metabolic homeostasis.

    Science.gov (United States)

    Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

    2012-10-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

  17. NF-kB as a mediator of brain inflammation in AD.

    Science.gov (United States)

    Hong, Jin Tae

    2017-08-07

    Alzheimer's disease is the most common form of dementia. It is characterized by beta-amyloid peptide fibrils which are extracellular deposition of a specific protein, and is accompanied by extensive neuroinflammation. Various studies show the presence of a number of inflammation markers in the AD brain: elevated inflammatory cytokines and chemokines, and an accumulation of activated microglia in the damaged regions. NF-kB is a redox of transcriptional factors, and it is known to be located in the genes involved in amyloidogenesis and inflammation. Epidemiological studies have shown that NF-kB is elevated in the AD patient brain, and long-term use of non-steroidal anti-inflammatory drugs suppresses the progression of AD and delays its onset, suggesting that there is a close correlation between NF-kB and AD pathogenesis. This study is (1) to assess the association between NF-kB activity and AD through discussion of a variety of experimental and clinical studies on AD and (2) to review treatment strategies designed to treat or prevent AD with NF-kB inhibitors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Histamine Induces Bovine Rumen Epithelial Cell Inflammatory Response via NF-κB Pathway

    Directory of Open Access Journals (Sweden)

    Xudong Sun

    2017-06-01

    Full Text Available Background/Aims: Subacute ruminal acidosis (SARA is a common disease in high-producing lactating cows. Rumenitis is the initial insult of SARA and is associated with the high concentrations of histamine produced in the rumen of dairy cows during SARA. However, the exact mechanism remains unclear. The objective of the current study is to investigate whether histamine induces inflammation of rumen epithelial cells and the underlying mechanism of this process. Methods: Bovine rumen epithelial cells were cultured and treated with different concentrations of histamine and pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor cultured in different pH medium (pH 7.2 or 5.5. qRT-PCR, Western-blotting, ELISA and immunocytofluorescence were used to evaluate whether histamine activated the NF-κB pathway and inflammatory cytokines. Results: The results showed that histamine significantly increased the activity of IKK β and the phosphorylation levels of IκB α, as well as upregulated the mRNA and protein expression levels of NF-κB p65 in the rumen epithelial cells cultured in neutral (pH=7.2 and acidic (pH=5.5 medium. Furthermore, histamine treatment also significantly increased the transcriptional activity of NF-κB p65. High expression and transcriptional activity of NF-κB p65 significantly increased the mRNA expressions and concentrations of inflammatory cytokines, tumor necrosis factor alpha (TNF-α, interleukin 6 (IL-6 and interleukin 1 beta (IL-1β, thereby inducing the inflammatory response in bovine rumen epithelial cells. However, inhibition of NF-κB p65 by PDTC significantly decreased the expressions and concentrations of the inflammatory cytokines induced by histamine in the rumen epithelial cells cultured in the neutral and acidic medium. Conclusion: The present data indicate that histamine induces the inflammatory response of bovine rumen epithelial cells through the NF-κB pathway.

  19. Directing traffic on DNA-How transcription factors relieve or induce transcriptional interference.

    Science.gov (United States)

    Hao, Nan; Palmer, Adam C; Dodd, Ian B; Shearwin, Keith E

    2017-03-15

    Transcriptional interference (TI) is increasingly recognized as a widespread mechanism of gene control, particularly given the pervasive nature of transcription, both sense and antisense, across all kingdoms of life. Here, we discuss how transcription factor binding kinetics strongly influence the ability of a transcription factor to relieve or induce TI.

  20. Role of nuclear factor of activated T-cells and activator protein-1 in the inhibition of interleukin-2 gene transcription by cannabinol in EL4 T-cells.

    Science.gov (United States)

    Yea, S S; Yang, K H; Kaminski, N E

    2000-02-01

    We previously reported that immunosuppressive cannabinoids inhibited interleukin (IL)-2 steady-state mRNA expression and secretion by phorbol-12-myristate-13-acetate plus ionomycin-activated mouse splenocytes and EL4 murine T-cells. Here we show that inhibition of IL-2 production by cannabinol, a modest central nervous system-active cannabinoid, is mediated through the inhibition of IL-2 gene transcription. Moreover, electrophoretic mobility shift assays demonstrated that cannabinol markedly inhibited the DNA binding activity of nuclear factor of activated T-cells (NF-AT) and activator protein-1 (AP-1) in a time- and concentration-dependent manner in activated EL4 cells. The inhibitory effects produced by cannabinol on AP-1 DNA binding were quite transient, showing partial recovery by 240 min after cell activation and no effect on the activity of a reporter gene under the control of AP-1. Conversely, cannabinol-mediated inhibition of NF-AT was robust and sustained as demonstrated by an NF-AT-regulated reporter gene. Collectively, these results suggest that decreased IL-2 production by cannabinol in EL4 cells is due to the inhibition of transcriptional activation of the IL-2 gene and is mediated, at least in part, through a transient inhibition of AP-1 and a sustained inhibition of NF-AT.

  1. Insect neuropeptide bursicon homodimers induce innate immune and stress genes during molting by activating the NF-κB transcription factor Relish.

    Directory of Open Access Journals (Sweden)

    Shiheng An

    Full Text Available BACKGROUND: Bursicon is a heterodimer neuropeptide composed of two cystine knot proteins, bursicon α (burs α and bursicon β (burs β, that elicits cuticle tanning (melanization and sclerotization through the Drosophila leucine-rich repeats-containing G protein-coupled receptor 2 (DLGR2. Recent studies show that both bursicon subunits also form homodimers. However, biological functions of the homodimers have remained unknown until now. METHODOLOGY/PRINCIPAL FINDINGS: In this report, we show in Drosophila melanogaster that both bursicon homodimers induced expression of genes encoding antimicrobial peptides (AMPs in neck-ligated adults following recombinant homodimer injection and in larvae fat body after incubation with recombinant homodimers. These AMP genes were also up-regulated in 24 h old unligated flies (when the endogenous bursicon level is low after injection of recombinant homodimers. Up-regulation of AMP genes by the homodimers was accompanied by reduced bacterial populations in fly assay preparations. The induction of AMP expression is via activation of the NF-κB transcription factor Relish in the immune deficiency (Imd pathway. The influence of bursicon homodimers on immune function does not appear to act through the heterodimer receptor DLGR2, i.e. novel receptors exist for the homodimers. CONCLUSIONS/SIGNIFICANCE: Our results reveal a mechanism of CNS-regulated prophylactic innate immunity during molting via induced expression of genes encoding AMPs and genes of the Turandot family. Turandot genes are also up-regulated by a broader range of extreme insults. From these data we infer that CNS-generated bursicon homodimers mediate innate prophylactic immunity to both stress and infection during the vulnerable molting cycle.

  2. Terminalia catappa Exerts Antimetastatic Effects on Hepatocellular Carcinoma through Transcriptional Inhibition of Matrix Metalloproteinase-9 by Modulating NF-κB and AP-1 Activity

    Directory of Open Access Journals (Sweden)

    Chao-Bin Yeh

    2012-01-01

    Full Text Available High mortality and morbidity rates for hepatocellular carcinoma (HCC in Taiwan primarily result from uncontrolled tumor metastasis. Previous studies have identified that Terminalia catappa leaf extracts (TCE exert hepatoprotective, antioxidative, antiinflammatory, anticancer, and antimetastatic activities. However, the effects of TCE on HCC and the underlying molecular mechanisms of its activities have yet to be fully elucidated. The present study's findings demonstrate that TCE concentration dependently inhibits human HCC migration/invasion. Zymographic and western blot analyses revealed that TCE inhibited the activities and expression of matrix metalloproteinase-9 (MMP-9. Assessment of mRNA levels, using reverse transcriptase polymerase chain reaction (PCR and real-time PCR, and promoter assays confirmed the inhibitory effects of TCE on MMP-9 expression in HCC cells. The inhibitory effects of TCE on MMP-9 proceeded by upregulating tissue inhibitor of metalloproteinase-1 (TIMP-1, as well as suppressing nuclear translocation and DNA binding activity of nuclear factor-kappa B (NF-κB and activating protein-1 (AP-1 on the MMP-9 promoter in Huh7 cells. In conclusion, TCE inhibits MMP-9 expression and HCC cell metastasis and, thus, has potential use as a chemopreventive agent. Its inhibitory effects are associated with downregulation of the binding activities of the transcription factors NF-κB and AP-1.

  3. DNA-dependent protein kinase participates in the radiation activation of NF-kB

    International Nuclear Information System (INIS)

    Rosenzweig, Kenneth E.; Youmell, Matthew B.; Price, Brendan D.

    1997-01-01

    The NF-kB transcription factor is maintained in an inactive state by binding to the lkBa inhibitory protein. Activation requires phosphorylation and degradation of lkBa, releasing active NF-kB. NF-kB can be activated by cytokines, antigens, free radicals and X-ray irradiation. The protein kinase responsible for phosphorylation of lkBa in vivo has not been fully characterized. Here, we have examined the role of the DNA-dependent protein kinases (DNA-PK) in the radiation-activation of NF-kB. Wortmannin is an inhibitor of DNA-PK and related kinases. Exposure of SW480 cells to wortmannin inhibited the radioactivation of NF-kB DNA-binding. Analysis of lkBa levels by western blotting indicated that wortmannin blocked the radiation induced degradation of lkBa. In in vitro experiments, purified DNA-PK was able to efficiently phosphorylate lkBa, and this phosphorylation was inhibited by wortmannin. In contrast, the induction of NF-kB activity by TNFa was unaffected by wortmannin. The results suggest that DNA-PK may phosphorylate lkBa following irradiation, leading to degradation of lkBa and the release of active NF-kB. The inability of wortmannin to block TNFa activation of NF-kB indicates there may be more than one pathway for the activation of NF-kB

  4. TRIM44 Is a Poor Prognostic Factor for Breast Cancer Patients as a Modulator of NF-κB Signaling.

    Science.gov (United States)

    Kawabata, Hidetaka; Azuma, Kotaro; Ikeda, Kazuhiro; Sugitani, Ikuko; Kinowaki, Keiichi; Fujii, Takeshi; Osaki, Akihiko; Saeki, Toshiaki; Horie-Inoue, Kuniko; Inoue, Satoshi

    2017-09-08

    Many of the tripartite motif (TRIM) proteins function as E3 ubiquitin ligases and are assumed to be involved in various events, including oncogenesis. In regard to tripartite motif-containing 44 (TRIM44), which is an atypical TRIM family protein lacking the RING finger domain, its pathophysiological significance in breast cancer remains unknown. We performed an immunohistochemical study of TRIM44 protein in clinical breast cancer tissues from 129 patients. The pathophysiological role of TRIM44 in breast cancer was assessed by modulating TRIM44 expression in MCF-7 and MDA-MB-231 breast cancer cells. TRIM44 strong immunoreactivity was significantly associated with nuclear grade ( p = 0.033), distant disease-free survival ( p = 0.031) and overall survival ( p = 0.027). Multivariate analysis revealed that the TRIM44 status was an independent prognostic factor for distant disease-free survival ( p = 0.005) and overall survival ( p = 0.002) of patients. siRNA-mediated TRIM44 knockdown significantly decreased the proliferation of MCF-7 and MDA-MB-231 cells and inhibited the migration of MDA-MB-231 cells. Microarray analysis and qRT-PCR showed that TRIM44 knockdown upregulated CDK19 and downregulated MMP1 in MDA-MB-231 cells. Notably, TRIM44 knockdown impaired nuclear factor-kappa B (NF-κB)-mediated transcriptional activity stimulated by tumor necrosis factor α (TNFα). Moreover, TRIM44 knockdown substantially attenuated the TNFα-dependent phosphorylation of the p65 subunit of NF-κB and IκBα in both MCF-7 and MDA-MB-231 cells. TRIM44 would play a role in the progression of breast cancer by promoting cell proliferation and migration, as well as by enhancing NF-κB signaling.

  5. NF-κB-IKKβ pathway as a target for drug development: realities, challenges and perspectives.

    Science.gov (United States)

    Freitas, Rosana H C N; Fraga, Carlos A M

    2018-02-19

    Nuclear factor κB (NF-κB) comprises a family of proteins that act as transcription factors promoting the expression of many genes. Activation of NF-κB biochemical cascades is associated with the regulation of innate and adaptive immune responses and inflammation, among other physiological responses. However, genetic abnormalities and continuous stimulation of the NF-κB-IKKβ pathway are directly related to many types of inflammatory and autoimmune diseases, as well as to the genesis and survival of tumor cells. Inhibition of the NF-κB-IKKβ cascade can be considered an attractive therapeutic method for the genesis of new prototypes to combat these chronic multifactorial diseases. This review describes some prototypes and drugs that act to inhibit the NF-κB-IKKβ pathway, highlighting the realities, challenges and perspectives for therapeutic use. Although only proteasome inhibitors, such as bortezomib and carfilzomib, are a reality as therapeutically useful drugs among the known modulators of possible targets in the NF-κB-IKKβ pathway, some other prototypes described as IKKβ inhibitors have entered clinical stages as drug candidates for the control of inflammatory diseases. It is important to note that some classical drugs available on the pharmaceutical market, such as acetylsalicylic acid, were also described more recently as NF-κB pathway modulators as IKKβ inhibitors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  6. Constitutive Activation of NF-KB in Prostate Carcinoma Cells Through a Positive Feedback Loop: Implication of Inducible IKK-Related Kinase (IKKi)

    National Research Council Canada - National Science Library

    Budunova, Irina V

    2005-01-01

    The overall goal of this project is to understand the role of inducible IKK-related kinase IKKi in constitutive activation of anti-apoptotic transcription factor NF-KB prostate carcinoma (PC) cells...

  7. The solution structure of the N-terminal zinc finger of GATA-1 reveals a specific binding face for the transcriptional co-factor FOG

    International Nuclear Information System (INIS)

    Kowalski, K.; Czolij, R.; King, G.F.; Crossley, M.; Mackay, J.P.

    1999-01-01

    Zinc fingers (ZnFs) are generally regarded as DNA-binding motifs. However, a number of recent reports have implicated particular ZnFs in the mediation of protein-protein interactions. The N-terminal ZnF of GATA-1 (NF) is one such finger, having been shown to interact with a number of other proteins, including the recently discovered transcriptional co-factor FOG. Here we solve the three-dimensional structure of the NF in solution using multidimensional 1H/15N NMR spectroscopy, and we use 1H/15N spin relaxation measurements to investigate its backbone dynamics. The structure consists of two distorted β-hairpins and a single α-helix, and is similar to that of the C-terminal ZnF of chicken GATA-1. Comparisons of the NF structure with those of other C4-type zinc binding motifs, including hormone receptor and LIM domains, also reveal substantial structural homology. Finally, we use the structure to map the spatial locations of NF residues shown by mutagenesis to be essential for FOG binding, and demonstrate that these residues all lie on a single face of the NF. Notably, this face is well removed from the putative DNA- binding face of the NF, an observation which is suggestive of simultaneous roles for the NF; that is, stabilisation of GATA-1 DNA complexes and recruitment of FOG to GATA-1-controlled promoter regions

  8. TcoF-DB: dragon database for human transcription co-factors and transcription factor interacting proteins

    KAUST Repository

    Schaefer, Ulf; Schmeier, Sebastian; Bajic, Vladimir B.

    2010-01-01

    The initiation and regulation of transcription in eukaryotes is complex and involves a large number of transcription factors (TFs), which are known to bind to the regulatory regions of eukaryotic DNA. Apart from TF-DNA binding, protein-protein interaction involving TFs is an essential component of the machinery facilitating transcriptional regulation. Proteins that interact with TFs in the context of transcription regulation but do not bind to the DNA themselves, we consider transcription co-factors (TcoFs). The influence of TcoFs on transcriptional regulation and initiation, although indirect, has been shown to be significant with the functionality of TFs strongly influenced by the presence of TcoFs. While the role of TFs and their interaction with regulatory DNA regions has been well-studied, the association between TFs and TcoFs has so far been given less attention. Here, we present a resource that is comprised of a collection of human TFs and the TcoFs with which they interact. Other proteins that have a proven interaction with a TF, but are not considered TcoFs are also included. Our database contains 157 high-confidence TcoFs and additionally 379 hypothetical TcoFs. These have been identified and classified according to the type of available evidence for their involvement in transcriptional regulation and their presence in the cell nucleus. We have divided TcoFs into four groups, one of which contains high-confidence TcoFs and three others contain TcoFs which are hypothetical to different extents. We have developed the Dragon Database for Human Transcription Co-Factors and Transcription Factor Interacting Proteins (TcoF-DB). A web-based interface for this resource can be freely accessed at http://cbrc.kaust.edu.sa/tcof/ and http://apps.sanbi.ac.za/tcof/. © The Author(s) 2010.

  9. TcoF-DB: dragon database for human transcription co-factors and transcription factor interacting proteins

    KAUST Repository

    Schaefer, Ulf

    2010-10-21

    The initiation and regulation of transcription in eukaryotes is complex and involves a large number of transcription factors (TFs), which are known to bind to the regulatory regions of eukaryotic DNA. Apart from TF-DNA binding, protein-protein interaction involving TFs is an essential component of the machinery facilitating transcriptional regulation. Proteins that interact with TFs in the context of transcription regulation but do not bind to the DNA themselves, we consider transcription co-factors (TcoFs). The influence of TcoFs on transcriptional regulation and initiation, although indirect, has been shown to be significant with the functionality of TFs strongly influenced by the presence of TcoFs. While the role of TFs and their interaction with regulatory DNA regions has been well-studied, the association between TFs and TcoFs has so far been given less attention. Here, we present a resource that is comprised of a collection of human TFs and the TcoFs with which they interact. Other proteins that have a proven interaction with a TF, but are not considered TcoFs are also included. Our database contains 157 high-confidence TcoFs and additionally 379 hypothetical TcoFs. These have been identified and classified according to the type of available evidence for their involvement in transcriptional regulation and their presence in the cell nucleus. We have divided TcoFs into four groups, one of which contains high-confidence TcoFs and three others contain TcoFs which are hypothetical to different extents. We have developed the Dragon Database for Human Transcription Co-Factors and Transcription Factor Interacting Proteins (TcoF-DB). A web-based interface for this resource can be freely accessed at http://cbrc.kaust.edu.sa/tcof/ and http://apps.sanbi.ac.za/tcof/. © The Author(s) 2010.

  10. The AP-1 Transcription Factor c-Jun Promotes Arthritis by Regulating Cyclooxygenase-2 and Arginase-1 Expression in Macrophages.

    Science.gov (United States)

    Hannemann, Nicole; Jordan, Jutta; Paul, Sushmita; Reid, Stephen; Baenkler, Hanns-Wolf; Sonnewald, Sophia; Bäuerle, Tobias; Vera, Julio; Schett, Georg; Bozec, Aline

    2017-05-01

    Activation of proinflammatory macrophages is associated with the inflammatory state of rheumatoid arthritis. Their polarization and activation are controlled by transcription factors such as NF-κB and the AP-1 transcription factor member c-Fos. Surprisingly, little is known about the role of the AP-1 transcription factor c-Jun in macrophage activation. In this study, we show that mRNA and protein levels of c-Jun are increased in macrophages following pro- or anti-inflammatory stimulations. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment cluster analyses of microarray data using wild-type and c-Jun-deleted macrophages highlight the central function of c-Jun in macrophages, in particular for immune responses, IL production, and hypoxia pathways. Mice deficient for c-Jun in macrophages show an amelioration of inflammation and bone destruction in the serum-induced arthritis model. In vivo and in vitro gene profiling, together with chromatin immunoprecipitation analysis of macrophages, revealed direct activation of the proinflammatory factor cyclooxygenase-2 and indirect inhibition of the anti-inflammatory factor arginase-1 by c-Jun. Thus, c-Jun regulates the activation state of macrophages and promotes arthritis via differentially regulating cyclooxygenase-2 and arginase-1 levels. Copyright © 2017 by The American Association of Immunologists, Inc.

  11. Effects of returning NF concentrate on the MBR-NF process treating antibiotic production wastewater.

    Science.gov (United States)

    Li, Kun; Cheng, Yutao; Wang, Jianxing; Zhang, Junya; Liu, Jibao; Yu, Dawei; Li, Mingyue; Wei, Yuansong

    2016-07-01

    The optimization of the nanofiltration (NF) concentrate backflow ratio (R cb) and the influence of the NF concentrate on the performance of membrane bioreactor-nanofiltration (MBR-NF) process treating antibiotic production wastewater were investigated on a laboratory scale. The R cb was optimized at 60 % based on the removal rates of chemical oxygen demand (COD) and NH4 (+)-N by MBR. Data analyses indicated that salinity brought by NF concentrate is the major driver leading to the decrease of sludge activity, especially at a high R cb. EPS analysis showed that electric conductivity (EC), proteins in soluble microbial products (SMP), and SMP brought by NF concentrate are the dominant factors causing the severe membrane fouling in MBR. Furthermore, undegradable substances including fulvic acid-like and humic acid-like compounds accumulated in NF concentrate showed significant influence on fouling of NF. MBR could well degrade small MW compounds in NF concentrate, which confirmed the enhancement of organic removal efficiency by recycling the NF concentrate to MBR. The MBR-NF process showed a relatively stable performance at the R cb of 60 % (volume reduction factor (VRF) = 5), and the NF permeate could satisfy the water quality standard for fermentation process with a water recovery rate of 90.9 %.

  12. The WRKY transcription factor family in Brachypodium distachyon.

    Science.gov (United States)

    Tripathi, Prateek; Rabara, Roel C; Langum, Tanner J; Boken, Ashley K; Rushton, Deena L; Boomsma, Darius D; Rinerson, Charles I; Rabara, Jennifer; Reese, R Neil; Chen, Xianfeng; Rohila, Jai S; Rushton, Paul J

    2012-06-22

    A complete assembled genome sequence of wheat is not yet available. Therefore, model plant systems for wheat are very valuable. Brachypodium distachyon (Brachypodium) is such a system. The WRKY family of transcription factors is one of the most important families of plant transcriptional regulators with members regulating important agronomic traits. Studies of WRKY transcription factors in Brachypodium and wheat therefore promise to lead to new strategies for wheat improvement. We have identified and manually curated the WRKY transcription factor family from Brachypodium using a pipeline designed to identify all potential WRKY genes. 86 WRKY transcription factors were found, a total higher than all other current databases. We therefore propose that our numbering system (BdWRKY1-BdWRKY86) becomes the standard nomenclature. In the JGI v1.0 assembly of Brachypodium with the MIPS/JGI v1.0 annotation, nine of the transcription factors have no gene model and eleven gene models are probably incorrectly predicted. In total, twenty WRKY transcription factors (23.3%) do not appear to have accurate gene models. To facilitate use of our data, we have produced The Database of Brachypodium distachyon WRKY Transcription Factors. Each WRKY transcription factor has a gene page that includes predicted protein domains from MEME analyses. These conserved protein domains reflect possible input and output domains in signaling. The database also contains a BLAST search function where a large dataset of WRKY transcription factors, published genes, and an extensive set of wheat ESTs can be searched. We also produced a phylogram containing the WRKY transcription factor families from Brachypodium, rice, Arabidopsis, soybean, and Physcomitrella patens, together with published WRKY transcription factors from wheat. This phylogenetic tree provides evidence for orthologues, co-orthologues, and paralogues of Brachypodium WRKY transcription factors. The description of the WRKY transcription factor

  13. Azadirachtin interacts with the tumor necrosis factor (TNF) binding domain of its receptors and inhibits TNF-induced biological responses.

    Science.gov (United States)

    Thoh, Maikho; Kumar, Pankaj; Nagarajaram, Hampathalu A; Manna, Sunil K

    2010-02-19

    The role of azadirachtin, an active component of a medicinal plant Neem (Azadirachta indica), on TNF-induced cell signaling in human cell lines was investigated. Azadirachtin blocks TNF-induced activation of nuclear factor kappaB (NF-kappaB) and also expression of NF-kappaB-dependent genes such as adhesion molecules and cyclooxygenase 2. Azadirachtin inhibits the inhibitory subunit of NF-kappaB (IkappaB alpha) phosphorylation and thereby its degradation and RelA (p65) nuclear translocation. It blocks IkappaB alpha kinase (IKK) activity ex vivo, but not in vitro. Surprisingly, azadirachtin blocks NF-kappaB DNA binding activity in transfected cells with TNF receptor-associated factor (TRAF)2, TNF receptor-associated death domain (TRADD), IKK, or p65, but not with TNFR, suggesting its effect is at the TNFR level. Azadirachtin blocks binding of TNF, but not IL-1, IL-4, IL-8, or TNF-related apoptosis-inducing ligand (TRAIL) with its respective receptors. Anti-TNFR antibody or TNF protects azadirachtin-mediated down-regulation of TNFRs. Further, in silico data suggest that azadirachtin strongly binds in the TNF binding site of TNFR. Overall, our data suggest that azadirachtin modulates cell surface TNFRs thereby decreasing TNF-induced biological responses. Thus, azadirachtin exerts an anti-inflammatory response by a novel pathway, which may be beneficial for anti-inflammatory therapy.

  14. Clusterin silencing sensitizes pancreatic cancer MIA-PaCa-2 cells to gmcitabine via regulation of NF-kB/Bcl-2 signaling.

    Science.gov (United States)

    Xu, Miao; Chen, Xiumei; Han, Yanling; Ma, Chunqing; Ma, Lin; Li, Shirong

    2015-01-01

    Clusterin (CLU) is known as a multifunctional protein involved in a variety of physiological processes including lipid transport, epithelial cell differentiation, tumorigenesis, and apoptosis. Our recent study has demonstrated that knockdown of clusterin sensitizes pancreatic cancer cell lines to gmcitabine treatment. However the details of this survival mechanism remain undefined. Of the various downstream targets of CLU, we examined activation of the NF-kB transcription factor and subsequent transcriptional regulation of BCL-2 gene in pancreatic cancer cell MIA-PaCa-2. The MIA-PaCa-2 cells were transfected with an antisense oligonucleotide (ASO) against clusterin, which led to a decreased protein level of the antiapoptotic gene BCL-2. Furthermore, inhibition of CLU decreased the function of NF-kB, which is capable of transcriptional regulation of the BCL-2 gene. Inhibiting this pathway increased the apoptotic effect of gmcitabine chemotherapy. Re-activated NF-kB resulted in attenuation of ASO-induced effects, followed by the bcl-2 upregulation, and bcl-2 re-inhibition resulted in attenuation of Re-activated NF-kB -induced effects. Animals injected with ASO CLU in MIA-PaCa-2 cells combined with gmcitabine treatment had fewer tumors than gmcitabine or ASO CLU alone. These findings suggest that knockdown of CLU sensitized MIA-PaCa-2 cells to gmcitabine chemotherapy through modulating NF-Kb/bcl-2 pathway.

  15. The effects of Mucuna pruriens on the renal oxidative stress and transcription factors in high-fructose-fed rats.

    Science.gov (United States)

    Ulu, Ramazan; Gozel, Nevzat; Tuzcu, Mehmet; Orhan, Cemal; Yiğit, İrem Pembegül; Dogukan, Ayhan; Telceken, Hafize; Üçer, Özlem; Kemeç, Zeki; Kaman, Dilara; Juturu, Vijaya; Sahin, Kazim

    2018-05-31

    In the present study, we evaluated the effects of M. pruriens administration on metabolic parameters, oxidative stress and kidney nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) signaling pathways in high-fructose fed rats. Male rats (n = 28) were divided into 4 groups as control, M. pruriens, fructose, and M. pruriens plus fructose. All rats were fed a standard diet supplemented or no supplemented with M. pruriens (200 mg/kg/d by gavage). Fructose was given in drinking water for 8 weeks. High fructose consumption led to an increase in the serum level of glucose, triglyceride, urea and renal malondialdehyde (MDA) levels. Although M. pruriens treatment reduced triglyceride and MDA levels, it did not affect other parameters. M. pruriens supplementation significantly decreased the expression of NF-ҡB and decreased expression of Nrf2 and HO-1 proteins in the kidney. This study showed that the adverse effects of high fructose were alleviated by M. pruriens supplementation via modulation of the expression of kidney nuclear transcription factors in rats fed high fructose diet. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Regulation of NF-κB oscillation by spatial parameters in true intracellular space (TiCS)

    Science.gov (United States)

    Ohshima, Daisuke; Sagara, Hiroshi; Ichikawa, Kazuhisa

    2013-10-01

    Transcription factor NF-κB is activated by cytokine stimulation, viral infection, or hypoxic environment leading to its translocation to the nucleus. The nuclear NF-κB is exported from the nucleus to the cytoplasm again, and by repetitive import and export, NF-κB shows damped oscillation with the period of 1.5-2.0 h. Oscillation pattern of NF-κB is thought to determine the gene expression profile. We published a report on a computational simulation for the oscillation of nuclear NF-κB in a 3D spherical cell, and showed the importance of spatial parameters such as diffusion coefficient and locus of translation for determining the oscillation pattern. Although the value of diffusion coefficient is inherent to protein species, its effective value can be modified by organelle crowding in intracellular space. Here we tested this possibility by computer simulation. The results indicate that the effective value of diffusion coefficient is significantly changed by the organelle crowding, and this alters the oscillation pattern of nuclear NF-κB.

  17. EGFRvIII promotes glioma angiogenesis and growth through the NF-κB, interleukin-8 pathway.

    Science.gov (United States)

    Bonavia, R; Inda, M M; Vandenberg, S; Cheng, S-Y; Nagane, M; Hadwiger, P; Tan, P; Sah, D W Y; Cavenee, W K; Furnari, F B

    2012-09-06

    Sustaining a high growth rate requires tumors to exploit resources in their microenvironment. One example of this is the extensive angiogenesis that is a typical feature of high-grade gliomas. Here, we show that expression of the constitutively active mutant epidermal growth factor receptor, ΔEGFR (EGFRvIII, EGFR*, de2-7EGFR) is associated with significantly higher expression levels of the pro-angiogenic factor interleukin (IL)-8 in human glioma specimens and glioma stem cells. Furthermore, the ectopic expression of ΔEGFR in different glioma cell lines caused up to 60-fold increases in the secretion of IL-8. Xenografts of these cells exhibit increased neovascularization, which is not elicited by cells overexpressing wild-type (wt)EGFR or ΔEGFR with an additional kinase domain mutation. Analysis of the regulation of IL-8 by site-directed mutagenesis of its promoter showed that ΔEGFR regulates its expression through the transcription factors nuclear factor (NF)-κB, activator protein 1 (AP-1) and CCAAT/enhancer binding protein (C/EBP). Glioma cells overexpressing ΔEGFR showed constitutive activation and DNA binding of NF-κB, overexpression of c-Jun and activation of its upstream kinase c-Jun N-terminal kinase (JNK) and overexpression of C/EBPβ. Selective pharmacological or genetic targeting of the NF-κB or AP-1 pathways efficiently blocked promoter activity and secretion of IL-8. Moreover, RNA interference-mediated knock-down of either IL-8 or the NF-κB subunit p65, in ΔEGFR-expressing cells attenuated their ability to form tumors and to induce angiogenesis when injected subcutaneously into nude mice. On the contrary, the overexpression of IL-8 in glioma cells lacking ΔEGFR potently enhanced their tumorigenicity and produced highly vascularized tumors, suggesting the importance of this cytokine and its transcription regulators in promoting glioma angiogenesis and tumor growth.

  18. EGF-R is Expressed and AP-1 and NF-κ:B Are Activated in Stromal Myofibroblasts Surrounding Colon Adenocarcinomas Paralleling Expression of COX-2 and VEGF

    Directory of Open Access Journals (Sweden)

    Panagiotis A. Konstantinopoulos

    2007-01-01

    Full Text Available Background: COX-2 and VEGF are important triggers of colon cancer growth, metastasis and angiogenesis. Cox-2 promoter contains transcriptional regulatory elements for AP-1 and NF-κ:B transcription factors whilst vegf is a known AP-1 downstream target gene. We investigated whether stromal myofibroblasts surrounding colon adenocarcinomas express COX-2 and VEGF and whether activation of AP-1 and NF-κ:B, as well as expression of EGF-R parallel expression of COX-2 and VEGF in these cells. Methods: Immunohistochemical methodology was performed on archival sections from 40 patients with colon adenocarcinomas. We evaluated c-FOS, p-c-JUN (phosphorylated c-JUN, p-Iκ:B-α (phosphorylated Iκ:B-α, EGF-R, COX-2, NF-κ:B and VEGF expression in stromal myofibroblasts surrounding colon adenocarcinomas. Double immunostaining with a-smooth muscle actin and each antibody was done to verify the expression of these molecules in stromal myofibroblasts. Results: VEGF, p-Iκ:B-α, NF-κ:B, c-FOS, p-c-JUN, EGF-R and COX-2 were expressed in stromal myofibroblasts surrounding colon adenocarcinomas in the majority of cases. EGF-R, p-Iκ:B-α, NF-κ:B, c-FOS and p-c-JUN correlated positively with COX-2 and VEGF expression. Conclusion: Stromal myofibroblasts surrounding colon adenocarcinomas are an important source of VEGF and COX-2 production, while AP-1 and NF-κ:B transcription factors are activated and EGF-R is expressed in these cells and associated with COX-2 and VEGF production.

  19. ß-Hydroxybutyrate Activates the NF-κB Signaling Pathway to Promote the Expression of Pro-Inflammatory Factors in Calf Hepatocytes

    Directory of Open Access Journals (Sweden)

    Xiaoxia Shi

    2014-01-01

    Full Text Available Background/Aims: ß-hydroxybutyrate (BHBA is the major component of ketone bodies in ketosis. Dairy cows with ketosis often undergo oxidative stress. BHBA is related to the inflammation involved in other diseases of dairy cattle. However, whether BHBA can induce inflammatory injury in dairy cow hepatocytes and the potential mechanism of this induction are not clear. The NF-κB pathway plays a vital role in the inflammatory response. Methods: Therefore, this study evaluated the oxidative stress, pro-inflammatory factors and NF-κB pathway in cultured calf hepatocytes treated with different concentrations of BHBA, pyrrolidine dithiocarbamate (PDTC, an NF-κB pathway inhibitor and N-acetylcysteine (NAC, antioxidant. Results: The results showed that BHBA could significantly increase the levels of oxidation indicators (MDA, NO and iNOS, whereas the levels of antioxidation indicators (GSH-Px, CAT and SOD were markedly decreased in hepatocytes. The IKKß activity and phospho-IκBa (p-IκBa contents were increased in BHBA-treated hepatocytes. This increase was accompanied by the increased expression level and transcription activity of p65. The expression levels of NF-κB-regulated inflammatory cytokines, namely TNF-a, IL-6 and IL-1ß, were markedly increased after BHBA treatment, while significantly decreased after NAC treatment. However, the p-IκBa level and the expression and activity of p65 and its target genes were markedly decreased in the PDTC + BHBA group compared with the BHBA (1.8 mM group. Moreover, immunocytofluorescence of p65 showed a similar trend. Conclusion: The present data indicate that higher concentrations of BHBA can induce cattle hepatocyte inflammatory injury through the NF-κB signaling pathway, which may be activated by oxidative stress.

  20. Intranuclear interactomic inhibition of NF-κB suppresses LPS-induced severe sepsis

    International Nuclear Information System (INIS)

    Park, Sung-Dong; Cheon, So Yeong; Park, Tae-Yoon; Shin, Bo-Young; Oh, Hyunju; Ghosh, Sankar; Koo, Bon-Nyeo; Lee, Sang-Kyou

    2015-01-01

    Suppression of nuclear factor-κB (NF-κB) activation, which is best known as a major regulator of innate and adaptive immune responses, is a potent strategy for the treatment of endotoxic sepsis. To inhibit NF-κB functions, we designed the intra-nuclear transducible form of transcription modulation domain (TMD) of RelA (p65), called nt-p65-TMD, which can be delivered effectively into the nucleus without influencing the cell viability, and work as interactomic inhibitors via disruption of the endogenous p65-mediated transcription complex. nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines, including TNF-α, IL-1β, or IL-6 from BV2 microglia cells stimulated by lipopolysaccharide (LPS). nt-p65-TMD did not inhibit tyrosine phosphorylation of signaling mediators such as ZAP-70, p38, JNK, or ERK involved in T cell activation, but was capable of suppressing the transcriptional activity of NF-κB without the functional effect on that of NFAT upon T-cell receptor (TCR) stimulation. The transduced nt-p65-TMD in T cell did not affect the expression of CD69, however significantly inhibited the secretion of T cell-specific cytokines such as IL-2, IFN-γ, IL-4, IL-17A, or IL-10. Systemic administration of nt-p65-TMD showed a significant therapeutic effect on LPS-induced sepsis model by inhibiting pro-inflammatory cytokines secretion. Therefore, nt-p65-TMD can be a novel therapeutics for the treatment of various inflammatory diseases, including sepsis, where a transcription factor has a key role in pathogenesis, and further allows us to discover new functions of p65 under normal physiological condition without genetic alteration. - Highlights: • The nt-p65-TMD is intra-nuclear interactomic inhibitor of endogenous p65. • The nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines. • The excellent therapeutic potential of nt-p65-TMD was confirmed in sepsis model

  1. Intranuclear interactomic inhibition of NF-κB suppresses LPS-induced severe sepsis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung-Dong [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Cheon, So Yeong [Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Park, Tae-Yoon; Shin, Bo-Young [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Oh, Hyunju; Ghosh, Sankar [Department of Microbiology and Immunology, College of Physicians and Surgeons, Columbia University, New York, NY 10032 (United States); Koo, Bon-Nyeo, E-mail: koobn@yuhs.ac [Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Lee, Sang-Kyou, E-mail: sjrlee@yonsei.ac.kr [Translational Research Center for Protein Function Control, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2015-08-28

    Suppression of nuclear factor-κB (NF-κB) activation, which is best known as a major regulator of innate and adaptive immune responses, is a potent strategy for the treatment of endotoxic sepsis. To inhibit NF-κB functions, we designed the intra-nuclear transducible form of transcription modulation domain (TMD) of RelA (p65), called nt-p65-TMD, which can be delivered effectively into the nucleus without influencing the cell viability, and work as interactomic inhibitors via disruption of the endogenous p65-mediated transcription complex. nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines, including TNF-α, IL-1β, or IL-6 from BV2 microglia cells stimulated by lipopolysaccharide (LPS). nt-p65-TMD did not inhibit tyrosine phosphorylation of signaling mediators such as ZAP-70, p38, JNK, or ERK involved in T cell activation, but was capable of suppressing the transcriptional activity of NF-κB without the functional effect on that of NFAT upon T-cell receptor (TCR) stimulation. The transduced nt-p65-TMD in T cell did not affect the expression of CD69, however significantly inhibited the secretion of T cell-specific cytokines such as IL-2, IFN-γ, IL-4, IL-17A, or IL-10. Systemic administration of nt-p65-TMD showed a significant therapeutic effect on LPS-induced sepsis model by inhibiting pro-inflammatory cytokines secretion. Therefore, nt-p65-TMD can be a novel therapeutics for the treatment of various inflammatory diseases, including sepsis, where a transcription factor has a key role in pathogenesis, and further allows us to discover new functions of p65 under normal physiological condition without genetic alteration. - Highlights: • The nt-p65-TMD is intra-nuclear interactomic inhibitor of endogenous p65. • The nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines. • The excellent therapeutic potential of nt-p65-TMD was confirmed in sepsis model.

  2. Modulation of the NF-kappaB pathway by Bordetella pertussis filamentous hemagglutinin.

    Directory of Open Access Journals (Sweden)

    Tzvia Abramson

    Full Text Available Filamentous hemagglutinin (FHA is a cell-associated and secreted adhesin produced by Bordetella pertussis with pro-apoptotic and pro-inflammatory activity in host cells. Given the importance of the NF-kappaB transcription factor family in these host cell responses, we examined the effect of FHA on NF-kappaB activation in macrophages and bronchial epithelial cells, both of which are relevant cell types during natural infection.Exposure to FHA of primary human monocytes and transformed U-937 macrophages, but not BEAS-2B epithelial cells, resulted in early activation of the NF-kappaB pathway, as manifested by the degradation of cytosolic IkappaB alpha, by NF-kappaB DNA binding, and by the subsequent secretion of NF-kappaB-regulated inflammatory cytokines. However, exposure of macrophages and human monocytes to FHA for two hours or more resulted in the accumulation of cytosolic IkappaB alpha, and the failure of TNF-alpha to activate NF-kappaB. Proteasome activity was attenuated following exposure of cells to FHA for 2 hours, as was the nuclear translocation of RelA in BEAS-2B cells.These results reveal a complex temporal dynamic, and suggest that despite short term effects to the contrary, longer exposures of host cells to this secreted adhesin may block NF-kappaB activation, and perhaps lead to a compromised immune response to this bacterial pathogen.

  3. Nuclear factor kB (NF-KB): signalosoma and its importance in cancer and inflammatories diseases

    International Nuclear Information System (INIS)

    Echeverri, Nancy P; Mockus, Ismena S

    2008-01-01

    The nuclear factor B (NF- B) is a dimer conformed by Rel family. NF- B is found in cytoplasm bound to inhibitor proteins (I B). I B are phosphorylated by different kinases who are part of signalosome as IeB kinases (IKK , IKK and NF- B essential modulator or NEMO), the mitogenic activated protein kinase (MAPK or p38) and NF-eB inducer kinase (NIK). These kinases are activated by different cytokines and ultraviolet light, I B phosphorylated induce their ubiquitination and proteosome degradation subsequently NF- B release and nucleus translocation. Nowadays, the NF- B activation by oxidative stress, genotoxic stress and DNA damage pathways. In contrast with the classical pathway, in this pathway there are a SUMOilation and nuclear translocation of NEMO. In nucleus NEMO interact with ataxia telangiectasia muted which is activated by chromatin changes and DNA damage. The complex ATM/NEMO is later translocated to cytoplasm where IKK is phosphorylated by ATM bringing to ubiquitination and thus NF- B releasing which is translocated to nucleus. NF- B induces survival rising antioxidants enzymes as superoxide dismutase, catalase and glutathione. These enzymes act in the control of oxidative species levels in the cell. NF- B over expression is related with inflammation and cancer. Nowadays, is development a pharmacological search which can act inhibiting NF- B signalosome molecules, not only to inflammatory disease whereas to radiotherapy and chemotherapy cancer resistance.

  4. Induction of cyclooxygenase-2 in macrophages by catalase: role of NF-kappaB and PI3K signaling pathways.

    Science.gov (United States)

    Jang, Byeong-Churl; Kim, Do-Hyun; Park, Jong-Wook; Kwon, Taeg Kyu; Kim, Sang-Pyo; Song, Dae-Kyu; Park, Jong-Gu; Bae, Jae-Hoon; Mun, Kyo-Chul; Baek, Won-Ki; Suh, Min-Ho; Hla, Timothy; Suh, Seong-Il

    2004-04-02

    Induction of COX-2 by catalase in smooth muscle cells, endothelial cells, and neuronal cells has been previously reported. However, the mechanism by which catalase up-regulates COX-2 remains poorly understood. In this study, we investigated the effect of catalase on induction of COX-2 in macrophages. The addition of catalase into Raw 264.7 macrophages induced COX-2 expression that was correlated with increased COX-2 transcription and mRNA stability. Catalase also induced activation of NF-kappaB, PI3K, ERKs, p38s, or JNKs. Catalase-induced COX-2 expression was abrogated by treatment of MG-132 (a NF-kappaB inhibitor) or LY294002 (a PI3K inhibitor), but not by treatment of PD98059 (an ERK inhibitor), SB203580 (a p38 inhibitor), or SP600125 (a JNK inhibitor). Moreover, inhibition of PI3K by LY294002 caused partial decrease of catalase-induced COX-2 transcription and steady-state COX-2 transcript levels, but not COX-2 mRNA stability. Together, these results suggest that catalase induces the expression of COX-2 in Raw 264.7 macrophages, and the induction is related with activation of NF-kappaB transcription factor and PI3K signaling pathway.

  5. The D. melanogaster capa-1 neuropeptide activates renal NF-kB signaling.

    Science.gov (United States)

    Terhzaz, Selim; Overend, Gayle; Sebastian, Sujith; Dow, Julian A T; Davies, Shireen-A

    2014-03-01

    The capa peptide family exists in a very wide range of insects including species of medical, veterinary and agricultural importance. Capa peptides act via a cognate G-protein coupled receptor (capaR) and have a diuretic action on the Malpighian tubules of Dipteran and Lepidopteran species. Capa signaling is critical for fluid homeostasis and has been associated with desiccation tolerance in the fly, Drosophila melanogaster. The mode of capa signaling is highly complex, affecting calcium, nitric oxide and cyclic GMP pathways. Such complex physiological regulation by cell signaling pathways may occur ultimately for optimal organismal stress tolerance to multiple stressors. Here we show that D. melanogaster capa-1 (Drome-capa-1) acts via the Nuclear Factor kappa B (NF-kB) stress signaling network. Human PCR gene arrays of capaR-transfected Human Embryonic Kidney (HEK) 293 cells showed that Drome-capa-1 increases expression of NF-kB, NF-kB regulated genes including IL8, TNF and PTGS2, and NF-kB pathway-associated transcription factors i.e. EGR1, FOS, cJUN. Furthermore, desiccated HEK293 cells show increased EGR1, EGR3 and PTGS2 - but not IL8, expression. CapaR-transfected NF-kB reporter cells showed that Drome-capa-1 increased NF-kB promoter activity via increased calcium. In Malpighian tubules, both Drome-capa-1 stimulation and desiccation result in increased gene expression of the D. melanogaster NF-kB orthologue, Relish; as well as EGR-like stripe and klumpfuss. Drome-capa-1 also induces Relish translocation in tubule principal cells. Targeted knockdown of Relish in only tubule principal cells reduces desiccation stress tolerance of adult flies. Together, these data suggest that Drome-capa-1 acts in desiccation stress tolerance, by activating NF-kB signaling. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. The Specificity of Innate Immune Responses Is Enforced by Repression of Interferon Response Elements by NF-κB p50

    Science.gov (United States)

    Cheng, Christine S.; Feldman, Kristyn E.; Lee, James; Verma, Shilpi; Huang, De-Bin; Huynh, Kim; Chang, Mikyoung; Ponomarenko, Julia V.; Sun, Shao-Cong; Benedict, Chris A.; Ghosh, Gourisankar; Hoffmann, Alexander

    2011-01-01

    The specific binding of transcription factors to cognate sequence elements is thought to be critical for the generation of specific gene expression programs. Members of the nuclear factor κB (NF-κB) and interferon (IFN) regulatory factor (IRF) transcription factor families bind to the κB site and the IFN response element (IRE), respectively, of target genes, and they are activated in macrophages after exposure to pathogens. However, how these factors produce pathogen-specific inflammatory and immune responses remains poorly understood. Combining top-down and bottom-up systems biology approaches, we have identified the NF-κB p50 homodimer as a regulator of IRF responses. Unbiased genome-wide expression and biochemical and structural analyses revealed that the p50 homodimer repressed a subset of IFN-inducible genes through a previously uncharacterized subclass of guanine-rich IRE (G-IRE) sequences. Mathematical modeling predicted that the p50 homodimer might enforce the stimulus specificity of composite promoters. Indeed, the production of the antiviral regulator IFN-β was rendered stimulus-specific by the binding of the p50 homodimer to the G-IRE–containing IFNβ enhancer to suppress cytotoxic IFN signaling. Specifically, a deficiency in p50 resulted in the inappropriate production of IFN-β in response to bacterial DNA sensed by Toll-like receptor 9. This role for the NF-κB p50 homodimer in enforcing the specificity of the cellular response to pathogens by binding to a subset of IRE sequences alters our understanding of how the NF-κB and IRF signaling systems cooperate to regulate antimicrobial immunity. PMID:21343618

  7. Fatty Acid–Regulated Transcription Factors in the Liver

    Science.gov (United States)

    Jump, Donald B.; Tripathy, Sasmita; Depner, Christopher M.

    2014-01-01

    Fatty acid regulation of hepatic gene transcription was first reported in the early 1990s. Several transcription factors have been identified as targets of fatty acid regulation. This regulation is achieved by direct fatty acid binding to the transcription factor or by indirect mechanisms where fatty acids regulate signaling pathways controlling the expression of transcription factors or the phosphorylation, ubiquitination, or proteolytic cleavage of the transcription factor. Although dietary fatty acids are well-established regulators of hepatic transcription factors, emerging evidence indicates that endogenously generated fatty acids are equally important in controlling transcription factors in the context of glucose and lipid homeostasis. Our first goal in this review is to provide an up-to-date examination of the molecular and metabolic bases of fatty acid regulation of key transcription factors controlling hepatic metabolism. Our second goal is to link these mechanisms to nonalcoholic fatty liver disease (NAFLD), a growing health concern in the obese population. PMID:23528177

  8. Constitutive Activation of NF-kappaB in Prostate Carcinoma Cells Through a Positive Feedback Loop: Implication of Inducible IKK-Related Kinase (IKKi)

    National Research Council Canada - National Science Library

    Budunova, Irina V

    2004-01-01

    The overall goal of this project is to understand the role of inducible IKK-related kinase IKKi in constitutive activation of anti-apoptotic transcription factor NF-kB prostate carcinoma (PC) cells...

  9. Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells

    International Nuclear Information System (INIS)

    Gao, Hui; Lin, Lu; Haq, Ihtesham Ul; Zeng, Shen-ming

    2016-01-01

    The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development. - Highlights: • FSH inhibits the activation of NF-κB in porcine primary granulosa cells. • Inhibition of NF-κB by FSH promotes autophagy via JNK signaling in granulosa cells. • Increased autophagy contributes to progesterone production in granulosa cells. • This is the first report against beclin1 regulation in porcine granulosa cells.

  10. Inhibition of NF-κB promotes autophagy via JNK signaling pathway in porcine granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Hui; Lin, Lu; Haq, Ihtesham Ul; Zeng, Shen-ming, E-mail: zengshenming@gmail.com

    2016-04-22

    The transcription factor nuclear factor-κB (NF-κB) plays an important role in diverse processes, including cell proliferation and differentiation, apoptosis and inflammation. However, the role of NF-κB in porcine follicle development is not clearly elucidated. In this study, we demonstrated that follicle stimulating hormone (FSH) increased the level of inhibitor of NF-κB (IκB) protein and promoted the cytoplasmic localization of p65, indicating that FSH inhibits the activation of NF-κB in porcine granulosa cells. Moreover, inhibition of NF-κB by FSH or another specific inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), could activate JNK signaling and enhance autophagic activity in porcine granulosa cells. Knockdown of RelA (p65) Subunit of NF-κB by RNA interference abrogated the activation of JNK signaling pathway and the increase of autophagic protein expression by FSH. Meanwhile, the functional significance of FSH or PDTC-mediated autophagy were further investigated. Our results demonstrated that the increased autophagy promoted progesterone secretion in porcine granulosa cells. Blockage of autophagy by chloroquine obviated the FSH or PDTC-induced progesterone production. Taken together, these results indicate that inhibition of NF-κB increased autophagy via JNK signaling, and promote steroidogenesis in porcine granulosa cells. Our results provide new insights into the regulation and function of autophagy in mammalian follicle development. - Highlights: • FSH inhibits the activation of NF-κB in porcine primary granulosa cells. • Inhibition of NF-κB by FSH promotes autophagy via JNK signaling in granulosa cells. • Increased autophagy contributes to progesterone production in granulosa cells. • This is the first report against beclin1 regulation in porcine granulosa cells.

  11. Chorionic gonadotropin regulates the transcript level of VHL, p53, and HIF-2alpha in human granulosa lutein cells.

    Science.gov (United States)

    Herr, D; Keck, C; Tempfer, C; Pietrowski, Detlef

    2004-12-01

    The ovarian corpus luteum plays a critical role in reproduction being the primary source of circulating progesterone. After ovulation the corpus luteum is build by avascular granulosa lutein cells through rapid vascularization regulated by gonadotropic hormones. The present study was performed to investigate whether this process might be influenced by the human chorionic gonadotropin (hCG)-dependent expression of different tumor suppressor genes and hypoxia dependent transcription factors. RNA was isolated from cultured granulosa lutein cells, transcribed into cDNA, and the transcript level of following genes were determined: RB-1, VHL, NF-1, NF-2, Wt-1, p53, APC, and hypoxia inducible factor-1 (HIF-1), -2, and -3alpha. Additionally, the influence of hCG on the expression of VHL, p53, and HIf2alpha were investigated. We demonstrate that in human granulosa lutein cells the tumor suppressor genes RB-1, VHL, NF-1, NF-2, Wt-1, p53, and APC and the hypoxia dependent transcription factors HIF-1alpha, -2alpha, and -3alpha are expressed. In addition, we showed that hCG regulates the expression of p53, VHL, and HIF-2alpha. Our results indicate that hCG may determine the growth and development of the corpus luteum by mediating hypoxic and apoptotic pathways in human granulosa lutein cells. Copyright 2004 Wiley-Liss, Inc.

  12. Competitive Promoter-Associated Matrix Attachment Region Binding of the Arid3a and Cux1 Transcription Factors

    Directory of Open Access Journals (Sweden)

    Dongkyoon Kim

    2017-12-01

    Full Text Available Arid3a/Bright/Dril1 is a B cell-specific transactivator that regulates immunoglobulin heavy chain (IgH gene transcription by binding promoter and enhancer-associated matrix attachment regions (MARs within the IgH gene locus. Promoter MAR-mediated Arid3a transactivation is antagonized by direct competition of MAR binding by Cux1/CDP—a ubiquitously expressed repressor originally termed NF-μNR. We report that the NF-μNR complex includes Arid3a in B cells but not in non-B cells through mobility shift assays. The binding activity of NF-μNR and Arid3a in B cells is reciprocally altered during the cell division cycle and by the B cell mitogen lipopolysaccharide LPS. LPS treatment had no effect on Arid3a localization but increased its total abundance within the nucleus and cytoplasm. We show that this increased level of Arid3a is capable of displacing Cux from the MARs to facilitate IgH gene transcription. Finally, we showed that the MARs (termed Bf150 and Tx125 associated with the VH1 rearranged variable region expressed in the S107 murine plasmacytoma, can repress reporter gene transcription in non-B cells and that they can relieve the repression mediated by Eμ enhancer in B cells. These results have significant implications for early human development and demonstrate that MARs in IgH locus, NF-µNR and Arid3a regulate IgH gene expression in a concerted fashion. This paves the way for future studies examining the misregulation of this pathway in pediatric disease.

  13. Foot-and-mouth disease virus leader proteinase inhibits dsRNA-induced type I interferon transcription by decreasing interferon regulatory factor 3/7 in protein levels

    International Nuclear Information System (INIS)

    Wang, Dang; Fang, Liurong; Luo, Rui; Ye, Rui; Fang, Ying; Xie, Lilan; Chen, Huanchun; Xiao, Shaobo

    2010-01-01

    Research highlights: → FMDV L pro inhibits poly(I:C)-induced IFN-α1/β mRNA expression. → L pro inhibits MDA5-mediated activation of the IFN-α1/β promoter. → L pro significantly reduced the transcription of multiple IRF-responsive genes. → L pro inhibits IFN-α1/β promoter activation by decreasing IRF-3/7 in protein levels. → The ability to process eIF-4G of L pro is not necessary to inhibit IFN-α1/β activation. -- Abstract: The leader proteinase (L pro ) of foot-and-mouth disease virus (FMDV) has been identified as an interferon-β (IFN-β) antagonist that disrupts the integrity of transcription factor nuclear factor κB (NF-κB). In this study, we showed that the reduction of double stranded RNA (dsRNA)-induced IFN-α1/β expression caused by L pro was also associated with a decrease of interferon regulatory factor 3/7 (IRF-3/7) in protein levels, two critical transcription factors for activation of IFN-α/β. Furthermore, overexpression of L pro significantly reduced the transcription of multiple IRF-responsive genes including 2',5'-OAS, ISG54, IP-10, and RANTES. Screening L pro mutants indicated that the ability to process eIF-4G of L pro is not required for suppressing dsRNA-induced activation of the IFN-α1/β promoter and decreasing IRF-3/7 expression. Taken together, our results demonstrate that, in addition to disrupting NF-κB, L pro also decreases IRF-3/7 expression to suppress dsRNA-induced type I IFN production, suggesting multiple strategies used by FMDV to counteract the immune response to viral infection.

  14. Melatonin Inhibits Androgen Receptor Splice Variant-7 (AR-V7)-Induced Nuclear Factor-Kappa B (NF-κB) Activation and NF-κB Activator-Induced AR-V7 Expression in Prostate Cancer Cells: Potential Implications for the Use of Melatonin in Castration-Resistant Prostate Cancer (CRPC) Therapy.

    Science.gov (United States)

    Liu, Vincent Wing Sun; Yau, Wing Lung; Tam, Chun Wai; Yao, Kwok-Ming; Shiu, Stephen Yuen Wing

    2017-05-31

    A major current challenge in the treatment of advanced prostate cancer, which can be initially controlled by medical or surgical castration, is the development of effective, safe, and affordable therapies against progression of the disease to the stage of castration resistance. Here, we showed that in LNCaP and 22Rv1 prostate cancer cells transiently overexpressing androgen receptor splice variant-7 (AR-V7), nuclear factor-kappa B (NF-κB) was activated and could result in up-regulated interleukin ( IL ) -6 gene expression, indicating a positive interaction between AR-V7 expression and activated NF-κB/IL-6 signaling in castration-resistant prostate cancer (CRPC) pathogenesis. Importantly, both AR-V7-induced NF-κB activation and IL-6 gene transcription in LNCaP and 22Rv1 cells could be inhibited by melatonin. Furthermore, stimulation of AR-V7 mRNA expression in LNCaP cells by betulinic acid, a pharmacological NF-κB activator, was reduced by melatonin treatment. Our data support the presence of bi-directional positive interactions between AR-V7 expression and NF-κB activation in CRPC pathogenesis. Of note, melatonin, by inhibiting NF-κB activation via the previously-reported MT₁ receptor-mediated antiproliferative pathway, can disrupt these bi-directional positive interactions between AR-V7 and NF-κB and thereby delay the development of castration resistance in advanced prostate cancer. Apparently, this therapeutic potential of melatonin in advanced prostate cancer/CRPC management is worth translation in the clinic via combined androgen depletion and melatonin repletion.

  15. Melatonin Inhibits Androgen Receptor Splice Variant-7 (AR-V7-Induced Nuclear Factor-Kappa B (NF-κB Activation and NF-κB Activator-Induced AR-V7 Expression in Prostate Cancer Cells: Potential Implications for the Use of Melatonin in Castration-Resistant Prostate Cancer (CRPC Therapy

    Directory of Open Access Journals (Sweden)

    Vincent Wing Sun Liu

    2017-05-01

    Full Text Available A major current challenge in the treatment of advanced prostate cancer, which can be initially controlled by medical or surgical castration, is the development of effective, safe, and affordable therapies against progression of the disease to the stage of castration resistance. Here, we showed that in LNCaP and 22Rv1 prostate cancer cells transiently overexpressing androgen receptor splice variant-7 (AR-V7, nuclear factor-kappa B (NF-κB was activated and could result in up-regulated interleukin (IL-6 gene expression, indicating a positive interaction between AR-V7 expression and activated NF-κB/IL-6 signaling in castration-resistant prostate cancer (CRPC pathogenesis. Importantly, both AR-V7-induced NF-κB activation and IL-6 gene transcription in LNCaP and 22Rv1 cells could be inhibited by melatonin. Furthermore, stimulation of AR-V7 mRNA expression in LNCaP cells by betulinic acid, a pharmacological NF-κB activator, was reduced by melatonin treatment. Our data support the presence of bi-directional positive interactions between AR-V7 expression and NF-κB activation in CRPC pathogenesis. Of note, melatonin, by inhibiting NF-κB activation via the previously-reported MT1 receptor-mediated antiproliferative pathway, can disrupt these bi-directional positive interactions between AR-V7 and NF-κB and thereby delay the development of castration resistance in advanced prostate cancer. Apparently, this therapeutic potential of melatonin in advanced prostate cancer/CRPC management is worth translation in the clinic via combined androgen depletion and melatonin repletion.

  16. Genetic Factors that Affect Tumorigenesis in NF1

    National Research Council Canada - National Science Library

    Stephens, Karen

    2003-01-01

    ...) that flank the NF1 gene. We identified recombination hotspots where 69% of NF1 microdeletions occur and developed robust and sensitive assays to detect microdeletions in a patient blood sample...

  17. Genetic Factors that Affect Tumorigenesis in NF1

    National Research Council Canada - National Science Library

    Stephens, Karen G

    2004-01-01

    ...) that flank the NF1 gene. We identified recombination hotspots where 69% of NF1 microdeletions occur and developed robust and sensitive assays to detect microdeletions in a patient blood sample...

  18. The Transcription Factor Encyclopedia

    DEFF Research Database (Denmark)

    Yusuf, Dimas; Butland, Stefanie L; Swanson, Magdalena I

    2012-01-01

    mini review articles on pertinent human, mouse and rat TFs. Notable features of the TFe website include a high-quality PDF generator and web API for programmatic data retrieval. TFe aims to rapidly educate scientists about the TFs they encounter through the delivery of succinct summaries written......ABSTRACT: Here we present the Transcription Factor Encyclopedia (TFe), a new web-based compendium of mini review articles on transcription factors (TFs) that is founded on the principles of open access and collaboration. Our consortium of over 100 researchers has collectively contributed over 130...

  19. NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

    International Nuclear Information System (INIS)

    Santos, Nuno R. dos; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T.

    2010-01-01

    Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL

  20. NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Nuno R. dos, E-mail: nrsantos@ualg.pt; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T. [IBB-Institute for Biotechnology and Bioengineering, Centre for Molecular and Structural Biomedicine (CBME), University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-11-05

    Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL.

  1. A Family of Salmonella Type III Secretion Effector Proteins Selectively Targets the NF-κB Signaling Pathway to Preserve Host Homeostasis.

    Science.gov (United States)

    Sun, Hui; Kamanova, Jana; Lara-Tejero, Maria; Galán, Jorge E

    2016-03-01

    Microbial infections usually lead to host innate immune responses and inflammation. These responses most often limit pathogen replication although they can also result in host-tissue damage. The enteropathogenic bacteria Salmonella Typhimurium utilizes a type III secretion system to induce intestinal inflammation by delivering specific effector proteins that stimulate signal transduction pathways resulting in the production of pro-inflammatory cytokines. We show here that a family of related Salmonella Typhimurium effector proteins PipA, GogA and GtgA redundantly target components of the NF-κB signaling pathway to inhibit transcriptional responses leading to inflammation. We show that these effector proteins are proteases that cleave both the RelA (p65) and RelB transcription factors but do not target p100 (NF-κB2) or p105 (NF-κB1). A Salmonella Typhimurium strain lacking these effectors showed increased ability to stimulate NF-κB and increased virulence in an animal model of infection. These results indicate that bacterial pathogens can evolve determinants to preserve host homeostasis and that those determinants can reduce the pathogen's virulence.

  2. Fisetin inhibits TNF-α/NF-κB-induced IL-8 expression by targeting PKCδ in human airway epithelial cells.

    Science.gov (United States)

    Lee, Seoghyun; Ro, Hyunju; In, Hyun Ju; Choi, Ji-Hee; Kim, Mun-Ock; Lee, Jinhyuk; Hong, Sung-Tae; Lee, Su Ui

    2018-08-01

    Fisetin (3,7,3',4'-tetrahydroxyflavone), a natural flavonoid, is a therapeutic agent for respiratory inflammatory diseases such as chronic obstructive pulmonary disease (COPD). However, detailed molecular mechanisms regarding the target protein of fisetin remain unknown. Fisetin significantly reduces tumour necrosis factor alpha (TNF-α)-induced interleukin (IL)-8 levels by inhibiting both nuclear factor kappa B (NF-κB) transcriptional activity and the phosphorylation of its upstream effectors. We show that fisetin prevents interactions between protein kinase C (PKC)δ and TNF receptor-associated factor 2 (TRAF2), thereby inhibiting the inhibitor of kappa B kinase (IKK)/NF-κB downstream signalling cascade. Furthermore, we found that fisetin directly binds to PKCδ in vitro. Our findings provide evidence that fisetin inhibits the TNF-α-activated IKK/NF-κB cascade by targeting PKCδ, thereby mediating inflammatory diseases such as COPD. These data suggest that fisetin is a good therapeutic drug for the treatment of inflammatory lung diseases, such as COPD, by inhibiting the TNF-α/NF-κB signalling pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Single-cell and population NF-κB dynamic responses depend on lipopolysaccharide preparation.

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    Miriam V Gutschow

    Full Text Available Lipopolysaccharide (LPS, found in the outer membrane of gram-negative bacteria, elicits a strong response from the transcription factor family Nuclear factor (NF-κB via Toll-like receptor (TLR 4. The cellular response to lipopolysaccharide varies depending on the source and preparation of the ligand, however. Our goal was to compare single-cell NF-κB dynamics across multiple sources and concentrations of LPS.Using live-cell fluorescence microscopy, we determined the NF-κB activation dynamics of hundreds of single cells expressing a p65-dsRed fusion protein. We used computational image analysis to measure the nuclear localization of the fusion protein in the cells over time. The concentration range spanned up to nine orders of magnitude for three E. coli LPS preparations. We find that the LPS preparations induce markedly different responses, even accounting for potency differences. We also find that the ability of soluble TNF receptor to affect NF-κB dynamics varies strikingly across the three preparations.Our work strongly suggests that the cellular response to LPS is highly sensitive to the source and preparation of the ligand. We therefore caution that conclusions drawn from experiments using one preparation may not be applicable to LPS in general.

  4. Histamine Induces Bovine Rumen Epithelial Cell Inflammatory Response via NF-κB Pathway.

    Science.gov (United States)

    Sun, Xudong; Yuan, Xue; Chen, Liang; Wang, Tingting; Wang, Zhe; Sun, Guoquan; Li, Xiaobing; Li, Xinwei; Liu, Guowen

    2017-01-01

    Subacute ruminal acidosis (SARA) is a common disease in high-producing lactating cows. Rumenitis is the initial insult of SARA and is associated with the high concentrations of histamine produced in the rumen of dairy cows during SARA. However, the exact mechanism remains unclear. The objective of the current study is to investigate whether histamine induces inflammation of rumen epithelial cells and the underlying mechanism of this process. Bovine rumen epithelial cells were cultured and treated with different concentrations of histamine and pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) cultured in different pH medium (pH 7.2 or 5.5). qRT-PCR, Western-blotting, ELISA and immunocytofluorescence were used to evaluate whether histamine activated the NF-κB pathway and inflammatory cytokines. The results showed that histamine significantly increased the activity of IKK β and the phosphorylation levels of IκB α, as well as upregulated the mRNA and protein expression levels of NF-κB p65 in the rumen epithelial cells cultured in neutral (pH=7.2) and acidic (pH=5.5) medium. Furthermore, histamine treatment also significantly increased the transcriptional activity of NF-κB p65. High expression and transcriptional activity of NF-κB p65 significantly increased the mRNA expressions and concentrations of inflammatory cytokines, tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1 beta (IL-1β), thereby inducing the inflammatory response in bovine rumen epithelial cells. However, inhibition of NF-κB p65 by PDTC significantly decreased the expressions and concentrations of the inflammatory cytokines induced by histamine in the rumen epithelial cells cultured in the neutral and acidic medium. The present data indicate that histamine induces the inflammatory response of bovine rumen epithelial cells through the NF-κB pathway. © 2017 The Author(s). Published by S. Karger AG, Basel.

  5. Oridonin stabilizes retinoic acid receptor alpha through ROS-activated NF-κB signaling.

    Science.gov (United States)

    Cao, Yang; Wei, Wei; Zhang, Nan; Yu, Qing; Xu, Wen-Bin; Yu, Wen-Jun; Chen, Guo-Qiang; Wu, Ying-Li; Yan, Hua

    2015-04-10

    Retinoic acid receptor alpha (RARα) plays an essential role in the regulation of many biological processes, such as hematopoietic cell differentiation, while abnormal RARα function contributes to the pathogenesis of certain diseases including cancers, especially acute promyelocytic leukemia (APL). Recently, oridonin, a natural diterpenoid isolated from Rabdosia rubescens, was demonstrated to regulate RARα by increasing its protein level. However, the underlying molecular mechanism for this action has not been fully elucidated. In the APL cell line, NB4, the effect of oridonin on RARα protein was analyzed by western blot and real-time quantitative RT-PCR analyses. Flow cytometry was performed to detect intracellular levels of reactive oxygen species (ROS). The association between nuclear factor-kappa B (NF-κB) signaling and the effect of oridonin was assessed using specific inhibitors, shRNA gene knockdown, and immunofluorescence assays. In addition, primary leukemia cells were treated with oridonin and analyzed by western blot in this study. RARα possesses transcriptional activity in the presence of its ligand, all-trans retinoic acid (ATRA). Oridonin remarkably stabilized the RARα protein, which retained transcriptional activity. Oridonin also moderately increased intracellular ROS levels, while pretreatment with the ROS scavenger, N-acetyl-l-cysteine (NAC), dramatically abrogated RARα stabilization by oridonin. More intriguingly, direct exposure to low concentrations of H2O2 also increased RARα protein but not mRNA levels, suggesting a role for ROS in oridonin stabilization of RARα protein. Further investigations showed that NAC antagonized oridonin-induced activation of NF-κB signaling, while the NF-κB signaling inhibitor, Bay 11-7082, effectively blocked the oridonin increase in RARα protein levels. In line with this, over-expression of IκΒα (A32/36), a super-repressor form of IκΒα, or NF-κB-p65 knockdown inhibited oridonin or H2O2-induced

  6. Development and Characterisation of a Novel NF-κB Reporter Cell Line for Investigation of Neuroinflammation

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    Marie-Theres Zeuner

    2017-01-01

    Full Text Available Aberrant activation of the transcription factor NF-κB, as well as uncontrolled inflammation, has been linked to autoimmune diseases, development and progression of cancer, and neurological disorders like Alzheimer’s disease. Reporter cell lines are a valuable state-of-the art tool for comparative analysis of in vitro drug screening. However, a reporter cell line for the investigation of NF-κB-driven neuroinflammation has not been available. Thus, we developed a stable neural NF-κB-reporter cell line to assess the potency of proinflammatory molecules and peptides, as well as anti-inflammatory pharmaceuticals. We used lentivirus to transduce the glioma cell line U251-MG with a tandem NF-κB reporter construct containing GFP and firefly luciferase allowing an assessment of NF-κB activity via fluorescence microscopy, flow cytometry, and luminometry. We observed a robust activation of NF-κB after exposure of the reporter cell line to tumour necrosis factor alpha (TNFα and amyloid-β peptide [1-42] as well as to LPS derived from Salmonella minnesota and Escherichia coli. Finally, we demonstrate that the U251-NF-κB-GFP-Luc reporter cells can be used for assessing the anti-inflammatory potential of pharmaceutical compounds using Bay11-7082 and IMD0354. In summary, our newly generated cell line is a robust and cost-efficient tool to study pro- and anti-inflammatory potential of drugs and biologics in neural cells.

  7. Altholactone Inhibits NF-κB and STAT3 Activation and Induces Reactive Oxygen Species-Mediated Apoptosis in Prostate Cancer DU145 Cells

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    Chunwa Jiang

    2017-02-01

    Full Text Available Altholactone, a natural compound isolated from Goniothalamus spp., has demonstrated anti-inflammatory and anticancer activities, but its molecular mechanisms are still not fully defined. Nuclear factor kappa B (NF-κB and signal transducer and activator of transcription 3 (STAT3 play pivotal roles in the cell survival of many human tumors. The objective of this study was to elucidate the mechanism of action of altholactone against prostate cancer DU145 cells and to evaluate whether its effects are mediated by inhibition of NF-κB and STAT3 activity. Altholactone inhibited proliferation of DU145 cells and induced cell cycle arrest in S phase and triggered apoptosis. Reporter assays revealed that altholactone repressed p65- and TNF-α-enhanced NF-κB transcriptional activity and also inhibited both constitutive and IL-6-induced transcriptional activity of STAT3. Consistent with this, altholactone down-regulated phosphorylation of STAT3 and moreover, decreased constitutively active mutant of STAT3 (STAT3C-induced transcriptional activity. Altholactone treatment also results in down-regulation of STAT3 target genes such as survivin, and Bcl-2 followed by up regulation of pro-apoptotic Bax protein. However, pre-treatment with the antioxidant N-acetylcysteine (NAC significantly inhibited the activation of Bax and prevented down-regulation of STAT3 target genes. Collectively, our findings suggest that altholactone induces DU145 cells death through inhibition of NF-κB and STAT3 activity.

  8. Innate immune responses: Crosstalk of signaling and regulation of gene transcription

    International Nuclear Information System (INIS)

    Zhong Bo; Tien Po; Shu Hongbing

    2006-01-01

    Innate immune responses to pathogens such as bacteria and viruses are triggered by recognition of specific structures of invading pathogens called pathogen-associated molecular patterns (PAMPs) by cellular pattern recognition receptors (PRRs) that are located at plasma membrane or inside cells. Stimulation of different PAMPs activates Toll-like receptor (TLR)-dependent and -independent signaling pathways that lead to activation of transcription factors nuclear factor-κB (NF-κB), interferon regulatory factor 3/7 (IRF3/7) and/or activator protein-1 (AP-1), which collaborate to induce transcription of a large number of downstream genes. This review focuses on the rapid progress that has recently improved our understanding of the crosstalk among the pathways and the precise regulation of transcription of the downstream genes

  9. Oleamide suppresses lipopolysaccharide-induced expression of iNOS and COX-2 through inhibition of NF-kappaB activation in BV2 murine microglial cells.

    Science.gov (United States)

    Oh, Young Taek; Lee, Jung Yeon; Lee, Jinhwa; Lee, Ju Hie; Kim, Ja-Eun; Ha, Joohun; Kang, Insug

    2010-05-03

    Oleamide (cis-9-octadecenamide) is an endogenous sleep-inducing fatty acid amide that accumulates in the cerebrospinal fluid of the sleep-deprived animals. Microglia are the major immune cells involved in neuroinflammation causing brain damage during infection, ischemia, and neurodegenerative disease. In this study, we examined the effects of oleamide on LPS-induced production of proinflammatory mediators and the mechanisms involved in BV2 microglia. Oleamide inhibited LPS-induced production of NO and prostaglandin E2 as well as expression of iNOS and COX-2. We showed that oleamide blocked LPS-induced NF-kappaB activation and phosphorylation of inhibitor kappaB kinase (IKK). We also showed that oleamide inhibited LPS-induced phosphorylation of Akt, p38 MAPK, and ERK, activation of PI 3-kinase, and accumulation of reactive oxygen species (ROS). Finally, we showed that a specific antagonist of the CB2 receptor, AM630, blocked the inhibitory effects of oleamide on LPS-induced production of proinflammatory mediators and activation of NF-kappaB. Taken together, our results suggest that oleamide shows an anti-inflammatory effect through inhibition of NF-kappaB activation in LPS-stimulated BV2 microglia. 2010 Elsevier Ireland Ltd. All rights reserved.

  10. HTLV Deregulation of the NF-κB Pathway: An Update on Tax and Antisense Proteins Role

    Science.gov (United States)

    Fochi, Stefania; Mutascio, Simona; Bertazzoni, Umberto; Zipeto, Donato; Romanelli, Maria G.

    2018-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL), an aggressive CD4+/CD25+ T-cell malignancy and of a severe neurodegenerative disease, HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The chronic activation or deregulation of the canonical and non-canonical nuclear factor kappa B (NF-κB) pathways play a crucial role in tumorigenesis. The HTLV-1 Tax-1 oncoprotein is a potent activator of the NF-κB transcription factors and the NF-κB response is required for promoting the development of HTLV-1 transformed cell lines. The homologous retrovirus HTLV-2, which also expresses a Tax-2 transforming protein, is not associated with ATL. In this review, we provide an updated synopsis of the role of Tax-1 in the deregulation of the NF-κB pathway, highlighting the differences with the homologous Tax-2. Special emphasis is directed toward the understanding of the molecular mechanisms involved in NF-κB activation resulting from Tax interaction with host factors affecting several cellular processes, such as cell cycle, apoptosis, senescence, cell proliferation, autophagy, and post-translational modifications. We also discuss the current knowledge on the role of the antisense viral protein HBZ in down-regulating the NF-κB activation induced by Tax, and its implication in cellular senescence. In addition, we review the recent studies on the mechanism of HBZ-mediated inhibition of NF-κB activity as compared to that exerted by the HTLV-2 antisense protein, APH-2. Finally, we discuss recent advances aimed at understanding the role exerted in the development of ATL by the perturbation of NF-κB pathway by viral regulatory proteins. PMID:29515558

  11. HTLV Deregulation of the NF-κB Pathway: An Update on Tax and Antisense Proteins Role.

    Science.gov (United States)

    Fochi, Stefania; Mutascio, Simona; Bertazzoni, Umberto; Zipeto, Donato; Romanelli, Maria G

    2018-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL), an aggressive CD4 + /CD25 + T-cell malignancy and of a severe neurodegenerative disease, HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The chronic activation or deregulation of the canonical and non-canonical nuclear factor kappa B (NF-κB) pathways play a crucial role in tumorigenesis. The HTLV-1 Tax-1 oncoprotein is a potent activator of the NF-κB transcription factors and the NF-κB response is required for promoting the development of HTLV-1 transformed cell lines. The homologous retrovirus HTLV-2, which also expresses a Tax-2 transforming protein, is not associated with ATL. In this review, we provide an updated synopsis of the role of Tax-1 in the deregulation of the NF-κB pathway, highlighting the differences with the homologous Tax-2. Special emphasis is directed toward the understanding of the molecular mechanisms involved in NF-κB activation resulting from Tax interaction with host factors affecting several cellular processes, such as cell cycle, apoptosis, senescence, cell proliferation, autophagy, and post-translational modifications. We also discuss the current knowledge on the role of the antisense viral protein HBZ in down-regulating the NF-κB activation induced by Tax, and its implication in cellular senescence. In addition, we review the recent studies on the mechanism of HBZ-mediated inhibition of NF-κB activity as compared to that exerted by the HTLV-2 antisense protein, APH-2. Finally, we discuss recent advances aimed at understanding the role exerted in the development of ATL by the perturbation of NF-κB pathway by viral regulatory proteins.

  12. Diisononyl phthalate aggravates allergic dermatitis by activation of NF-kB.

    Science.gov (United States)

    Kang, Jun; Song, Jing; Shen, Shiping; Li, Baizhan; Yang, Xu; Chen, Mingqing

    2016-12-20

    Several epidemiological studies have suggested a possible link between exposure to Diisononyl phthalate (DINP) and the development of allergies. These findings remain controversial since there is insufficient scientific evidence to assess the ability of DINP to influence allergic immune responses. In addition, the mechanisms behind DINP-caused allergic diseases have not been fully elucidated. In this study, Balb/c mice were orally exposed to DINP for 3 weeks and were then sensitized with fluorescein isothiocyanate (FITC). We showed that oral exposure to DINP could aggravate allergic-dermatitis-like lesions, indicated by an increase in the number of mast cells, and in increased skin edema in FITC-induced contact hypersensitivity. This deterioration was concomitant with increased total serum immunoglobulin-E and Th2 cytokines. We determined the oxidative damage and the activation of nuclear factor-kb (NF-kB). The data demonstrated that DINP could promote oxidative damage and the activation of NF-kB in the skin. The expression of thymic stromal lymphopoietin and the activation of signal transducer and activator of transcriptions 3, 5 and 6 were enhanced concomitant with exacerbated allergic dermatitis effects and the activation of NF-kB induced by DINP. These effects were alleviated by pyrollidine dithiocarbamate, an inhibitor of NF-kB. The results suggest that oral exposure to DINP aggravated allergic contact dermatitis, which was positively regulated via NF-kB.

  13. Renin-angiotensin system inhibition ameliorates CCl4-induced liver fibrosis in mice through the inactivation of nuclear transcription factor kappa B.

    Science.gov (United States)

    Saber, Sameh; Mahmoud, Amr A A; Helal, Noha S; El-Ahwany, Eman; Abdelghany, Rasha H

    2018-06-01

    Therapeutic interventions for liver fibrosis are still limited due to the complicated molecular pathogenesis. Renin-angiotensin system (RAS) seems to contribute to the development of hepatic fibrosis. Therefore, we aimed to examine the effect of RAS inhibition on CCl 4 -induced liver fibrosis. Mice were treated with silymarin (30 mg·kg -1 ), perindopril (1 mg·kg -1 ), fosinopril (2 mg·kg -1 ), or losartan (10 mg·kg -1 ). The administration of RAS inhibitors improved liver histology and decreased protein expression of alpha smooth muscle actin (α-SMA) and hepatic content of hydroxyproline. These effects found to be mediated via inactivation of nuclear transcription factor kappa B (NFκB) pathway by the inhibition of NFκB p65 phosphorylation at the Ser536 residue and phosphorylation-induced degradation of nuclear factor kappa-B inhibitor alpha (NFκBia) subsequently inhibited NFκB-induced TNF-α and TGF-β1, leading to lower levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF). We concluded that the tissue affinity of the angiotensin converting enzyme inhibitors (ACEIs) has no impact on its antifibrotic activity and that interfering the RAS either through the inhibition of ACE or the blockade of AT1R has the same therapeutic benefit. These results suggest RAS inhibitors as promising candidates for further clinical trials in the management of hepatic fibrosis.

  14. [The expression and significance of receptor activator of nuclear factor kappaB ligand and osteoprotegerin in periapical cyst and periapical granuloma].

    Science.gov (United States)

    Zhang, Meihua; Yu, Yunzhi; Miao, Yu

    2012-08-01

    To investigate the expression of receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) in periapical cyst and periapical granuloma by comparison with the expression in the normal periodontal tissue as control, and to identify their functional mechanism in the bone destruction of periapical cyst and granuloma. 20 periapical cyst tissues (cyst group), 20 periapical granuloma tissues (granuloma group), and 20 normal periodontal tissues (control group) were collected respectively. Immunohistochemical technology was performed to detect the expression of RANKL and OPG in above three groups. In cyst group, granuloma group and control group, the expression of RANKL were 75.00 +/- 7.54, 68.40 +/- 6.74 and 29.40 +/- 2.46, respectively. The expression of OPG were 38.10 +/- 7.09, 47.65 +/- 13.85 and 58.60 +/- 5.88, respectively. The differences among the three groups were statistically significant (Pcysts group were negatively correlated (r=-0.56, P=0.01) and were not correlated with granuloma and control group (P>0.05). RANKL and OPG play roles in the bone absorption of periapical disease. In periapical disease, abnormal expression of RANKL and OPG are detected, RANKL significantly increase, OPG decrease, bone absorption accelerate and osteolytic lesion are observed. In periapical cyst, the bone absorption is more active compared with periapical granuloma.

  15. Agmatine inhibits nuclear factor-κB nuclear translocation in acute spinal cord compression injury rat model

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    Doaa M. Samy

    2016-09-01

    Full Text Available Secondary damage after acute spinal cord compression injury (SCCI exacerbates initial insult. Nuclear factor kappa-B (NF-κB-p65 activation is involved in SCCI deleterious effects. Agmatine (Agm showed neuroprotection against various CNS injuries. However, Agm impact on NF-κB signaling in acute SCCI remains to be investigated. The present study compared the effectiveness of Agm therapy and decompression laminectomy (DL in functional recovery, oxidative stress, inflammatory and apoptotic responses, and modulation of NF-κB activation in acute SCCI rat model. Rats were either sham-operated or subjected to SCCI at T8–9, using 2-Fr. catheter. SCCI rats were randomly treated with DL at T8–9, intraperitoneal Agm (100 mg/kg/day, combined (DL/Agm treatment or saline (n = 16/group. After 28-days of neurological follow-up, spinal cords were either subjected to biochemical measurement of oxidative stress and inflammatory markers or histopathology and immuno-histochemistry for NF-κB-p65 and caspase-3 expression (n = 8/group. Agm was comparable to DL in facilitating neurological functions recovery, reducing inflammation (TNF-α/interleukin-6, and apoptosis. Agm was distinctive in combating oxidative stress. Agm neuroprotective effects were paralleled with inhibition of NF-κB-p65 nuclear translocation. Combined pharmacological and surgical interventions were proved superior in functional recovery. In conclusion, present research suggested a new mechanism for Agm neuroprotection in rats SCCI through inhibition of NF-κB activation.

  16. Exercise Training Mitigates Water Pipe Smoke Exposure-Induced Pulmonary Impairment via Inhibiting NF-κB and Activating Nrf2 Signalling Pathways

    Directory of Open Access Journals (Sweden)

    Abderrahim Nemmar

    2018-01-01

    Full Text Available Water pipe smoking is a tobacco smoking method commonly used in Eastern countries and is gaining popularity in Europe and North America, in particular among adolescents and young adults. Several clinical and experimental studies have reported that exposure to water pipe smoke (WPS induces lung inflammation and impairment of pulmonary function. However, the mechanisms of such effects are not understood, as are data on the possible palliative effect of exercise training. The present study evaluated the effects of regular aerobic exercise training (treadmill: 5 days/week, 40 min/day on subchronic exposure to WPS (30 minutes/day, 5 days/week for 2 months. C57BL/6 mice were exposed to air or WPS with or without exercise training. Airway resistance measured using forced oscillation technique was significantly and dose-dependently increased in the WPS-exposed group when compared with the air-exposed one. Exercise training significantly prevented the effect of WPS on airway resistance. Histologically, the lungs of WPS-exposed mice had focal moderate interstitial inflammatory cell infiltration consisting of neutrophil polymorphs, plasma cells, and lymphocytes. There was a mild increase in intra-alveolar macrophages and a focal damage to alveolar septae in some foci. Exercise training significantly alleviated these effects and also decreased the WPS-induced increase of tumor necrosis factor α and interleukin 6 concentrations and attenuated the increase of 8-isoprostane in lung homogenates. Likewise, the lung DNA damage induced by WPS was significantly inhibited by exercise training. Moreover, exercise training inhibited nuclear factor kappa-B (NF-κB expression induced by WPS and increased that of nuclear factor erythroid 2-related factor 2 (Nrf2. Our findings suggest that exercise training significantly mitigated WPS-induced increase in airway resistance, inflammation, oxidative stress, and DNA damage via mechanisms that include inhibiting NF-κB and

  17. NF-kB and c-Jun induce the expression of the oncogenic miR-221 and miR-222 in prostate carcinoma and glioblastoma cells

    Science.gov (United States)

    Galardi, Silvia; Mercatelli, Neri; Farace, Maria G.; Ciafrè, Silvia A.

    2011-01-01

    MicroRNAs (miRNAs) are potent negative regulators of gene expression involved in all aspects of cell biology. They finely modulate virtually all physiological pathways in metazoans, and are deeply implicated in all main pathologies, among which cancer. Mir-221 and miR-222, two closely related miRNAs encoded in cluster from a genomic region on chromosome X, are strongly upregulated in several forms of human tumours. In this work, we report that the ectopic modulation of NF-kB modifies miR-221/222 expression in prostate carcinoma and glioblastoma cell lines, where we had previously shown their oncogenic activity. We identify two separate distal regions upstream of miR-221/222 promoter which are bound by the NF-kB subunit p65 and drive efficient transcription in luciferase reporter assays; consistently, the site-directed mutagenesis disrupting p65 binding sites or the ectopical inhibition of NF-kB activity significantly reduce luciferase activity. In the most distal enhancer region, we also define a binding site for c-Jun, and we show that the binding of this factor cooperates with that of p65, fully accounting for the observed upregulation of miR-221/222. Thus our work uncovers an additional mechanism through which NF-kB and c-Jun, two transcription factors deeply involved in cancer onset and progression, contribute to oncogenesis, by inducing miR-221/222 transcription. PMID:21245048

  18. The oncoprotein gankyrin interacts with RelA and suppresses NF-κB activity

    International Nuclear Information System (INIS)

    Higashitsuji, Hiroaki; Higashitsuji, Hisako; Liu, Yu; Masuda, Tomoko; Fujita, Takanori; Abdel-Aziz, H. Ismail; Kongkham, Supranee; Dawson, Simon; John Mayer, R.; Itoh, Yoshito; Sakurai, Toshiharu; Itoh, Katsuhiko; Fujita, Jun

    2007-01-01

    Gankyrin is an oncoprotein commonly overexpressed in hepatocellular carcinomas. It interacts with multiple proteins and accelerates degradation of tumor suppressors Rb and p53. Since gankyrin consists of 7 ankyrin repeats and is structurally similar to IκBs, we investigated its interaction with NF-κB. We found that gankyrin directly binds to RelA. In HeLa and 293 cells, overexpression of gankyrin suppressed the basal as well as TNFα-induced transcriptional activity of NF-κB, whereas down-regulation of gankyrin increased it. Gankyrin did not affect the NF-κB DNA-binding activity or nuclear translocation of RelA induced by TNFα in these cells. Leptomycin B that inhibits nuclear export of RelA suppressed the NF-κB activity, which was further suppressed by gankyrin. The inhibitory effect of gankyrin was abrogated by nicotinamide as well as down-regulation of SIRT1, a class III histone deacetylase. Thus, gankyrin binds to NF-κB and suppresses its activity at the transcription level by modulating acetylation via SIRT1

  19. NF-κB activity in muscle from obese and type 2 diabetic subjects under basal and exercise-stimulated conditions.

    Science.gov (United States)

    Tantiwong, Puntip; Shanmugasundaram, Karthigayan; Monroy, Adriana; Ghosh, Sangeeta; Li, Mengyao; DeFronzo, Ralph A; Cersosimo, Eugenio; Sriwijitkamol, Apiradee; Mohan, Sumathy; Musi, Nicolas

    2010-11-01

    NF-κB is a transcription factor that controls the gene expression of several proinflammatory proteins. Cell culture and animal studies have implicated increased NF-κB activity in the pathogenesis of insulin resistance and muscle atrophy. However, it is unclear whether insulin-resistant human subjects have abnormal NF-κB activity in muscle. The effect that exercise has on NF-κB activity/signaling also is not clear. We measured NF-κB DNA-binding activity and the mRNA level of putative NF-κB-regulated myokines interleukin (IL)-6 and monocyte chemotactic protein-1 (MCP-1) in muscle samples from T2DM, obese, and lean subjects immediately before, during (40 min), and after (210 min) a bout of moderate-intensity cycle exercise. At baseline, NF-κB activity was elevated 2.1- and 2.7-fold in obese nondiabetic and T2DM subjects, respectively. NF-κB activity was increased significantly at 210 min following exercise in lean (1.9-fold) and obese (2.6-fold) subjects, but NF-κB activity did not change in T2DM. Exercise increased MCP-1 mRNA levels significantly in the three groups, whereas IL-6 gene expression increased significantly only in lean and obese subjects. MCP-1 and IL-6 gene expression peaked at the 40-min exercise time point. We conclude that insulin-resistant subjects have increased basal NF-κB activity in muscle. Acute exercise stimulates NF-κB in muscle from nondiabetic subjects. In T2DM subjects, exercise had no effect on NF-κB activity, which could be explained by the already elevated NF-κB activity at baseline. Exercise-induced MCP-1 and IL-6 gene expression precedes increases in NF-κB activity, suggesting that other factors promote gene expression of these cytokines during exercise.

  20. Sargahydroquinoic acid inhibits TNFα-induced AP-1 and NF-κB signaling in HaCaT cells through PPARα activation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Youngsic; Jung, Yujung; Kim, Min Cheol; Kwon, Hak Cheol [Natural Medicine Center, KIST Gangneung Institute, Gangneung 210-340 (Korea, Republic of); Kang, Ki Sung [College of Korean Medicine, Gachon University, Seongnam 461-701 (Korea, Republic of); Kim, Yong Kee, E-mail: yksnbk@sm.ac.kr [College of Pharmacy, Sookmyung Women’s University, Seoul 140-742 (Korea, Republic of); Kim, Su-Nam, E-mail: snkim@kist.re.kr [Natural Medicine Center, KIST Gangneung Institute, Gangneung 210-340 (Korea, Republic of)

    2014-08-08

    Highlights: • SHQA increases PPARα/γ transactivation and inhibits MMP-2/-9 expression. • SHQA inhibits TNFα-induced AP-1 and MAPK signaling. • SHQA inhibits TNFα-induced p65 translocation and IκBα phosphorylation. • SHQA inhibits TNFα-induced AP-1 and NF-κB signaling via PPARα. - Abstract: Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors and expressed in various cell types in the skin, including keratinocytes, fibroblasts and infiltrating immune cells. Thus, their ligands are targets for the treatment of various skin disorders, such as photo-aging and chronological aging of skin. Intensive studies have revealed that PPARα/γ functions in photo-aging and age-related inflammation by regulating matrix metalloproteinases (MMPs) via activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB). However, the detailed mechanism of PPARα/γ’s role in skin aging has not yet been elucidated. In this study, we confirmed that sargahydroquinoic acid (SHQA) as a PPARα/γ ligand significantly decreased Tumor Necrosis Factor-alpha (TNFα)-induced MMP-2/-9 expression by downregulating TNFα-induced transcription factors, subsequently reducing IκBα degradation and blocking NF-κB p65 nuclear translocation in HaCaT human epidermal keratinocyte cells. Treatment of cells with SHQA and GW6471 (PPARα antagonist) not bisphenol A diglycidyl ether (PPARγ antagonists), reversed the effect on TNFα-induced inflammatory signaling pathway activation. Taken together, our data suggest that SHQA inhibit TNFα-induced MMP-2/-9 expression and age-related inflammation by suppressing AP-1 and NF-κB pathway via PPARα.

  1. Increased expression of NF-AT3 and NF-AT4 in the atria correlates with procollagen I carboxyl terminal peptide and TGF-β1 levels in serum of patients with atrial fibrillation.

    Science.gov (United States)

    Zhao, Fei; Zhang, ShiJiang; Chen, YiJiang; Gu, WeiDong; Ni, BuQing; Shao, YongFeng; Wu, YanHu; Qin, JianWei

    2014-11-25

    Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. Unfortunately, the precise mechanisms and sensitive serum biomarkers of atrial remodeling in AF remain unclear. The aim of this study was to determine whether the expression of the transcription factors NF-AT3 and NF-AT4 correlate with atrial structural remodeling of atrial fibrillation and serum markers for collagen I and III synthesis. Right and left atrial specimens were obtained from 90 patients undergoing valve replacement surgery. The patients were divided into sinus rhythm (n = 30), paroxysmal atrial fibrillation (n = 30), and persistent atrial fibrillation (n = 30) groups. NF-AT3, NF-AT4, and collagen I and III mRNA and protein expression in atria were measured. We also tested the levels of the carboxyl-terminal peptide from pro-collagen I, the N-terminal type I procollagen propeptides, the N-terminal type III procollagen propeptides, and TGF-β1 in serum using an enzyme immunosorbent assay. NF-AT3 and NF-AT4 mRNA and protein expression were increased in the AF groups, especially in the left atrium. NF-AT3 and NF-AT4 expression in the right atrium was increased in the persistent atrial fibrillation group compared the sinus rhythm group with similar valvular disease. In patients with AF, the expression levels of nuclear NF-AT3 and NF-AT4 correlated with those of collagens I and III in the atria and with PICP and TGF-β1 in blood. These data support the hypothesis that nuclear NF-AT3 and NF-AT4 participates in atrial structural remodeling, and that PICP and TGF-β1 levels may be sensitive serum biomarkers to estimate atrial structural remodeling with atrial fibrillation.

  2. Long noncoding RNA PANDA and scaffold-attachment-factor SAFA control senescence entry and exit.

    Science.gov (United States)

    Puvvula, Pavan Kumar; Desetty, Rohini Devi; Pineau, Pascal; Marchio, Agnés; Moon, Anne; Dejean, Anne; Bischof, Oliver

    2014-11-19

    Cellular senescence is a stable cell cycle arrest that limits the proliferation of pre-cancerous cells. Here we demonstrate that scaffold-attachment-factor A (SAFA) and the long noncoding RNA PANDA differentially interact with polycomb repressive complexes (PRC1 and PRC2) and the transcription factor NF-YA to either promote or suppress senescence. In proliferating cells, SAFA and PANDA recruit PRC complexes to repress the transcription of senescence-promoting genes. Conversely, the loss of SAFA-PANDA-PRC interactions allows expression of the senescence programme. Accordingly, we find that depleting either SAFA or PANDA in proliferating cells induces senescence. However, in senescent cells where PANDA sequesters transcription factor NF-YA and limits the expression of NF-YA-E2F-coregulated proliferation-promoting genes, PANDA depletion leads to an exit from senescence. Together, our results demonstrate that PANDA confines cells to their existing proliferative state and that modulating its level of expression can cause entry or exit from senescence.

  3. Sumoylation of IkB attenuates NF-kB-induced nitrosative stress at rostral ventrolateral medulla and cardiovascular depression in experimental brain death.

    Science.gov (United States)

    Tsai, Ching-Yi; Li, Faith C H; Wu, Carol H Y; Chang, Alice Y W; Chan, Samuel H H

    2016-09-22

    Small ubiquitin-related modifier (SUMO) is a group of proteins that participates in post-translational modifications. One known SUMO target is the transcription factor nuclear factor-kB (NF-kB) that plays a pivotal role in many disease processes; sumoylation inactivates NF-kB by conjugation with inhibitors of NF-kB (IkB). Our laboratory demonstrated previously that transcriptional upregulation of nitric oxide synthase II (NOS II) by NF-kB, leading to nitrosative stress by the formation of peroxynitrite in the rostral ventrolateral medulla (RVLM), underpins the defunct brain stem cardiovascular regulation that precedes brain death. Based on an experimental endotoxemia model, this study evaluated the hypothesis that sumoylation plays a pro-life role in brain death by interacting with the NF-kB/NOS II/peroxynitrite signaling pathway in the RVLM. In Sprague-Dawley rats, intravenous administration of Escherichia coli lipopolysaccharide (LPS; 10 mg kg -1 ) elicited an augmentation of SUMO-1 and ubiquitin-conjugase 9 (Ubc9) mRNA or protein levels, alongside SUMO-1-conjugated proteins in the RVLM. Immunoneutralization of SUMO-1 or Ubc9 in the RVLM significantly potentiated the already diminished sumoylation of IkBα and intensified NF-kB activation and NOS II/peroxynitrite expression in this brain stem substrate, together with exacerbated fatality, cardiovascular depression and reduction of an experimental index of a life-and-death signal detected from arterial pressure that disappears in comatose patients signifying failure of brain stem cardiovascular regulation before brain death. We conclude that sumoylation of IkB in the RVLM ameliorates the defunct brain stem cardiovascular regulation that underpins brain death in our experimental endotoxemia modal by reducing nitrosative stress via inhibition of IkB degradation that diminishes the induction of the NF-kB/NOS II/peroxynitrite signaling cascade.

  4. Emodin attenuates high glucose-induced TGF-β1 and fibronectin expression in mesangial cells through inhibition of NF-κB pathway

    International Nuclear Information System (INIS)

    Yang, Jie; Zeng, Zhi; Wu, Teng; Yang, Zhicheng; Liu, Bing; Lan, Tian

    2013-01-01

    The activation of nuclear factor-κB (NF-κB) and the subsequent overexpression of its downstream targets transforming growth factor-β1 (TGF-β1) and fibronectin (FN) are among the hallmarks for the progressive diabetic nephropathy. Our previous studies demonstrated that emodin ameliorated renal injury and inhibited extracellular matrix accumulation in kidney and mesangial cells under diabetic condition. However, the molecular mechanism has not been fully elucidated. Here, we showed that emodin significantly attenuated high glucose-induced NF-κB nuclear translocation in mesangial cells. Interestingly, emodin also inhibited the DNA-binding activity and transcriptional activity of NF-κB. Furthermore, NF-κB-mediated TGF-β1 and FN expression was significantly decreased by emodin. These results demonstrated that emodin suppressed TGF-β1 and FN overexpression through inhibition of NF-κB activation, suggesting that emodin-mediated inhibition of the NF-κB pathway could protect against diabetic nephropathy. - Highlights: • Emodin decreased high glucose-induced p65 phosphorylation in MCs. • Emodin decreased high glucose-induced IκB-α degradation in MCs. • Emodin decreased high glucose-induced p65 translocation in MCs. • Emodin blocked high glucose-induced NF-κB activity. • Emodin blocked high glucose-induced the expression of TGF-β1 and FN

  5. In silico identification of NF-kappaB-regulated genes in pancreatic beta-cells

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    Eizirik Decio L

    2007-02-01

    Full Text Available Abstract Background Pancreatic beta-cells are the target of an autoimmune attack in type 1 diabetes mellitus (T1DM. This is mediated in part by cytokines, such as interleukin (IL-1β and interferon (IFN-γ. These cytokines modify the expression of hundreds of genes, leading to beta-cell dysfunction and death by apoptosis. Several of these cytokine-induced genes are potentially regulated by the IL-1β-activated transcription factor (TF nuclear factor (NF-κB, and previous studies by our group have shown that cytokine-induced NF-κB activation is pro-apoptotic in beta-cells. To identify NF-κB-regulated gene networks in beta-cells we presently used a discriminant analysis-based approach to predict NF-κB responding genes on the basis of putative regulatory elements. Results The performance of linear and quadratic discriminant analysis (LDA, QDA in identifying NF-κB-responding genes was examined on a dataset of 240 positive and negative examples of NF-κB regulation, using stratified cross-validation with an internal leave-one-out cross-validation (LOOCV loop for automated feature selection and noise reduction. LDA performed slightly better than QDA, achieving 61% sensitivity, 91% specificity and 87% positive predictive value, and allowing the identification of 231, 251 and 580 NF-κB putative target genes in insulin-producing INS-1E cells, primary rat beta-cells and human pancreatic islets, respectively. Predicted NF-κB targets had a significant enrichment in genes regulated by cytokines (IL-1β or IL-1β + IFN-γ and double stranded RNA (dsRNA, as compared to genes not regulated by these NF-κB-dependent stimuli. We increased the confidence of the predictions by selecting only evolutionary stable genes, i.e. genes with homologs predicted as NF-κB targets in rat, mouse, human and chimpanzee. Conclusion The present in silico analysis allowed us to identify novel regulatory targets of NF-κB using a supervised classification method based on

  6. Lipocalin 2 Suppresses Ocular Inflammation by Inhibiting the Activation of NF-κβ Pathway in Endotoxin-Induced Uveitis

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    Wenyi Tang

    2018-03-01

    Full Text Available Background/Aims: Lipocalin 2 (LCN2, an important mediator of a variety of cellular processes, is involved in regulating the inflammatory response, but its roles in different inflammatory diseases are controversial. Because the role of LCN2 in ocular inflammation has been unclear until now, we explored the function of LCN2 in lipopolysaccharide (LPS-induced ocular inflammation in vivo and in vitro. Methods: Endotoxin-induced uveitis (EIU was induced in male Sprague Dawley rats by the intravitreal injection of LPS. The expression and location of LCN2 in the retina were detected with western blotting and immunohistochemistry, respectively. We determined the clinical scores for anterior inflammation, quantified the infiltrated inflammatory cells, and measured the pro-inflammatory factors to determine the anti-inflammatory effects of LCN2 in EIU eyes. Cultured primary rat Müller cells were stimulated with LPS and the expression and secretion of LCN2 were measured with real-time PCR, western blotting, and an ELISA. After Müller cells were cotreated with LPS and LCN2 or PBS, the expression and secretion of TNF-α, IL-6, and MCP-1 were examined with realtime PCR, western blotting, and ELISAs. Western blotting and immunofluorescence were used to detect the phosphorylation and cellular distribution of nuclear factor kappaB (NF-κB subunit p65. Results: In EIU, the expression of LCN2 was significantly upregulated in the retina, especially in the outer nuclear layer (mainly composed of Müller cells. LPS stimulation of cultured Müller cells also markedly elevated LCN2 expression. Intravitreal injection of LCN2 significantly reduced the clinical scores, inflammatory infiltration, and protein leakage in EIU, which correlated with the reduced levels of proinflammatory factors in the aqueous humor and retina. LCN2 treatment also reduced the expression and secretion of TNF-α, IL-6, and MCP-1 in LPS-stimulated Müller cells. LCN2 inhibited the inflammatory

  7. TNF-α-induced NF-κB activation promotes myofibroblast differentiation of LR-MSCs and exacerbates bleomycin-induced pulmonary fibrosis.

    Science.gov (United States)

    Hou, Jiwei; Ma, Tan; Cao, Honghui; Chen, Yabing; Wang, Cong; Chen, Xiang; Xiang, Zou; Han, Xiaodong

    2018-03-01

    Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and irreversible lung disease of unknown cause. It has been reported that both lung resident mesenchymal stem cells (LR-MSCs) and tumor necrosis factor-α (TNF-α) play important roles in the development of pulmonary fibrosis. However, the underlying connections between LR-MSCs and TNF-α in the pathogenesis of pulmonary fibrosis are still elusive. In this study, we found that the pro-inflammatory cytokine TNF-α and the transcription factor nuclear factor kappa B (NF-κB) p65 subunit were both upregulated in bleomycin-induced fibrotic lung tissue. In addition, we discovered that TNF-α promotes myofibroblast differentiation of LR-MSCs through activating NF-κB signaling. Interestingly, we also found that TNF-α promotes the expression of β-catenin. Moreover, we demonstrated that suppression of the NF-κB signaling could attenuate myofibroblast differentiation of LR-MSCs and bleomycin-induced pulmonary fibrosis which were accompanied with decreased expression of β-catenin. Our data implicates that inhibition of the NF-κB signaling pathway may provide a therapeutic strategy for pulmonary fibrosis, a disease that warrants more effective treatment approaches. © 2017 Wiley Periodicals, Inc.

  8. MCPIP1 contributes to the toxicity of proteasome inhibitor MG-132 in HeLa cells by the inhibition of NF-κB.

    Science.gov (United States)

    Skalniak, Lukasz; Dziendziel, Monika; Jura, Jolanta

    2014-10-01

    Recently, we have shown that the treatment of cells with proteasome inhibitor MG-132 results in the induction of expression of monocyte chemotactic protein-1 induced protein 1 (MCPIP1). MCPIP1 is a ribonuclease, responsible for the degradation of transcripts encoding certain pro-inflammatory cytokines. The protein is also known as an inhibitor of NF-κB transcription factor. Thanks to its molecular properties, MCPIP1 is considered as a regulator of inflammation, differentiation, and survival. Using siRNA technology, we show here that MCPIP1 expression contributes to the toxic properties of MG-132 in HeLa cells. The inhibition of proteasome by MG-132 and epoxomicin markedly increased MCPIP1 expression. While MG-132 induces HeLa cell death, down-regulation of MCPIP1 expression by siRNA partially protects HeLa cells from MG-132 toxicity and restores Nuclear factor-κB (NF-κB) activity, inhibited by MG-132 treatment. Inversely, overexpression of MCPIP1 decreased constitutive activity of NF-κB and limited the survival of HeLa cells, as we have shown in the previous study. Interestingly, although MG-132 decreased the expression of IκBα and increased p65 phosphorylation, the inhibition of constitutive NF-κB activity was observed in MG-132-treated cells. Since the elevated constitutive activity of NF-κB is one of the mechanisms providing increased survival of cancer cells, including HeLa cells, we propose that death-promoting properties of MCPIP1 in MG-132-treated HeLa cells may, at least partially, derive from the negative effect on the constitutive NF-κB activity.

  9. Negative regulation of human parathyroid hormone gene promoter by vitamin D3 through nuclear factor Y

    International Nuclear Information System (INIS)

    Jaeaeskelaeinen, T.; Huhtakangas, J.; Maeenpaeae, P.H.

    2005-01-01

    The negative regulation of the human parathyroid hormone (PTH) gene by biologically active vitamin D 3 (1,25-dihydroxyvitamin D 3 ; 1,25(OH) 2 D 3 ) was studied in rat pituitary GH4C1 cells, which express factors needed for the negative regulation. We report here that NF-Y binds to sequences downstream of the site previously reported to bind the vitamin D receptor (VDR). Additional binding sites for NF-Y reside in the near vicinity and were shown to be important for full activity of the PTH gene promoter. VDR and NF-Y were shown to exhibit mutually exclusive binding to the VDRE region. According to our results, sequestration of binding partners for NF-Y by VDR also affects transcription through a NF-Y consensus binding element in GH4C1 but not in ROS17/2.8 cells. These results indicate that 1,25(OH) 2 D 3 may affect transcription of the human PTH gene both by competitive binding of VDR and NF-Y, and by modulating transcriptional activity of NF-Y

  10. Novel insights into the role of NF-κB p50 in astrocyte-mediated fate specification of adult neural progenitor cells

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    Valeria Bortolotto

    2017-01-01

    Full Text Available Within the CNS nuclear factor-kappa B (NF-κB transcription factors are involved in a wide range of functions both in homeostasis and in pathology. Over the years, our and other groups produced a vast array of information on the complex involvement of NF-κB proteins in different aspects of postnatal neurogenesis. In particular, several extracellular signals and membrane receptors have been identified as being able to affect neural progenitor cells (NPC and their progeny via NF-κB activation. A crucial role in the regulation of neuronal fate specification in adult hippocampal NPC is played by the NF-κB p50 subunit. NF-κB p50KO mice display a remarkable reduction in adult hippocampal neurogenesis which correlates with a selective defect in hippocampal-dependent short-term memory. Moreover absence of NF-κB p50 can profoundly affect the in vitro proneurogenic response of adult hippocampal NPC (ahNPC to several endogenous signals and drugs. Herein we briefly review the current knowledge on the pivotal role of NF-κB p50 in the regulation of adult hippocampal neurogenesis. In addition we discuss more recent data that further extend the relevance of NF-κB p50 to novel astroglia-derived signals which can influence neuronal specification of ahNPC and to astrocyte-NPC cross-talk.

  11. CC2D1A Regulates Human Intellectual and Social Function as well as NF-κB Signaling Homeostasis

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    M. Chiara Manzini

    2014-08-01

    Full Text Available Autism spectrum disorder (ASD and intellectual disability (ID are often comorbid, but the extent to which they share common genetic causes remains controversial. Here, we present two autosomal-recessive “founder” mutations in the CC2D1A gene causing fully penetrant cognitive phenotypes, including mild-to-severe ID, ASD, as well as seizures, suggesting shared developmental mechanisms. CC2D1A regulates multiple intracellular signaling pathways, and we found its strongest effect to be on the transcription factor nuclear factor κB (NF-κB. Cc2d1a gain and loss of function both increase activation of NF-κB, revealing a critical role of Cc2d1a in homeostatic control of intracellular signaling. Cc2d1a knockdown in neurons reduces dendritic complexity and increases NF-κB activity, and the effects of Cc2d1a depletion can be rescued by inhibiting NF-κB activity. Homeostatic regulation of neuronal signaling pathways provides a mechanism whereby common founder mutations could manifest diverse symptoms in different patients.

  12. NIK is required for NF-κB-mediated induction of BAG3 upon inhibition of constitutive protein degradation pathways.

    Science.gov (United States)

    Rapino, F; Abhari, B A; Jung, M; Fulda, S

    2015-03-12

    Recently, we reported that induction of the co-chaperone Bcl-2-associated athanogene 3 (BAG3) is critical for recovery of rhabdomyosarcoma (RMS) cells after proteotoxic stress upon inhibition of the two constitutive protein degradation pathways, that is, the ubiquitin-proteasome system by Bortezomib and the aggresome-autophagy system by histone deacetylase 6 (HDAC6) inhibitor ST80. In the present study, we investigated the molecular mechanisms mediating BAG3 induction under these conditions. Here, we identify nuclear factor-kappa B (NF-κB)-inducing kinase (NIK) as a key mediator of ST80/Bortezomib-stimulated NF-κB activation and transcriptional upregulation of BAG3. ST80/Bortezomib cotreatment upregulates mRNA and protein expression of NIK, which is accompanied by an initial increase in histone H3 acetylation. Importantly, NIK silencing by siRNA abolishes NF-κB activation and BAG3 induction by ST80/Bortezomib. Furthermore, ST80/Bortezomib cotreatment stimulates NF-κB transcriptional activity and upregulates NF-κB target genes. Genetic inhibition of NF-κB by overexpression of dominant-negative IκBα superrepressor (IκBα-SR) or by knockdown of p65 blocks the ST80/Bortezomib-stimulated upregulation of BAG3 mRNA and protein expression. Interestingly, inhibition of lysosomal activity by Bafilomycin A1 inhibits ST80/Bortezomib-stimulated IκBα degradation, NF-κB activation and BAG3 upregulation, indicating that IκBα is degraded via the lysosome in the presence of Bortezomib. Thus, by demonstrating a critical role of NIK in mediating NF-κB activation and BAG3 induction upon ST80/Bortezomib cotreatment, our study provides novel insights into mechanisms of resistance to proteotoxic stress in RMS.

  13. Purinergic signaling is required for fluid shear stress-induced NF-{kappa}B translocation in osteoblasts

    Energy Technology Data Exchange (ETDEWEB)

    Genetos, Damian C., E-mail: dgenetos@ucdavis.edu [Department of Anatomy, Cell Biology, and Physiology, School of Veterinary Medicine, University of California, Davis, CA (United States); Karin, Norman J. [Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, WA (United States); Geist, Derik J. [Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN (United States); Donahue, Henry J. [Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Pennsylvania State College of Medicine, Hershey, PA (United States); Duncan, Randall L. [Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN (United States)

    2011-04-01

    Fluid shear stress regulates gene expression in osteoblasts, in part by activation of the transcription factor NF-{kappa}B. We examined whether this process was under the control of purinoceptor activation. MC3T3-E1 osteoblasts under static conditions expressed the NF-{kappa}B inhibitory protein I{kappa}B{alpha} and exhibited cytosolic localization of NF-{kappa}B. Under fluid shear stress, I{kappa}B{alpha} levels decreased, and concomitant nuclear localization of NF-{kappa}B was observed. Cells exposed to fluid shear stress in ATP-depleted medium exhibited no significant reduction in I{kappa}B{alpha}, and NF-{kappa}B remained within the cytosol. Similar results were found using oxidized ATP or Brilliant Blue G, P2X{sub 7} receptor antagonists, indicating that the P2X{sub 7} receptor is responsible for fluid shear-stress-induced I{kappa}B{alpha} degradation and nuclear accumulation of NF-{kappa}B. Pharmacologic blockage of the P2Y6 receptor also prevented shear-induced I{kappa}B{alpha} degradation. These phenomena involved neither ERK1/2 signaling nor autocrine activation by P2X{sub 7}-generated lysophosphatidic acid. Our results suggest that fluid shear stress regulates NF-{kappa}B activity through the P2Y{sub 6} and P2X{sub 7} receptor.

  14. Transcriptional Response of Human Cells to Microbeam Irradiation with 2.1 MeV Alpha Particles

    Science.gov (United States)

    Hellweg, C. E.; Bogner, S.; Spitta, L.; Arenz, A.; Baumstark-Khan, C.; Greif, K. D.; Giesen, U.

    Within the next decades an increasing number of human beings in space will be simultaneously exposed to different stimuli especially microgravity and radiation To assess the risks for humans during long-duration space missions the complex interplay of these parameters at the cellular level must be understood Cellular stress protection responses lead to increased transcription of several genes via modulation of transcription factors Activation of the Nuclear Factor kappa B NF- kappa B pathway as a possible anti-apoptotic route represents such an important cellular stress response A screening assay for detection of NF- kappa B-dependent gene activation using the destabilized variant of Enhanced Green Fluorescent Protein d2EGFP as reporter protein had been developed It consists of Human Embryonic Kidney HEK 293 Cells stably transfected with a receptor-reporter-construct carrying d2EGFP under the control of a NF- kappa B response element Clones positive for Tumor Necrosis Factor alpha TNF- alpha inducible d2EGFP expression were selected as cellular reporters Irradiation was performed either with X-rays 150 kV 19 mA at DLR Cologne or with 2 1 MeV alpha particles LET sim 160 keV mu m at PTB Braunschweig After irradiation the following biological endpoints were determined i cell survival via the colony forming ability test ii time-dependent activation of NF- kappa B dependent d2EGFP gene expression using flow cytometry iii quantitative RT-PCR

  15. NAC transcription factors: structurally distinct, functionally diverse

    DEFF Research Database (Denmark)

    Olsen, Addie Nina; Ernst, Heidi A; Leggio, Leila Lo

    2005-01-01

    level and localization, and to the first indications of NAC participation in transcription factor networks. The recent determination of the DNA and protein binding NAC domain structure offers insight into the molecular functions of the protein family. Research into NAC transcription factors has......NAC proteins constitute one of the largest families of plant-specific transcription factors, and the family is present in a wide range of land plants. Here, we summarize the biological and molecular functions of the NAC family, paying particular attention to the intricate regulation of NAC protein...

  16. RUNX1: A Regulator of NF-kB Signaling in Pulmonary Diseases.

    Science.gov (United States)

    Tang, Xiaoju; Sun, Ling; Wang, Gang; Chen, Bojiang; Luo, Fengming

    2018-01-01

    Runt-related transcription factor 1 (RUNX1), a member of the RUNX family, is one of the key regulatory proteins in vertebrates. RUNX1 is involved in embryonic development, hematopoiesis, angiogenesis, tumorigenesis and immune response. In the past few decades, studies mainly focused on the effect of RUNX1 on acute leukemia and cancer. Only few studies about the function of RUNX1 in the pathological process of pulmonary diseases have been reported. Recent studies have demonstrated that RUNX1 is highly expressed in both mesenchymal and epithelial compartments of the developing and postnatal lung and that it plays a critical role in the lipopolysaccharide induced lung inflammation by regulating the NF-kB pathway. RUNX1 participates in the regulation of the NF-kB signaling pathway through interaction with IkB kinase complex in the cytoplasm or interaction with the NF-kB subunit P50. NF-kB is well-known signaling pathway necessary for inflammatory response in the lung. This review is to highlight the RUNX1 structure, isoforms and to present the mechanism that RUNX1 regulates NF-kB. This will illustrate the great potential role of RUNX1 in the inflammation signaling pathway in pulmonary diseases. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Complexity of CNC transcription factors as revealed by gene targeting of the Nrf3 locus.

    Science.gov (United States)

    Derjuga, Anna; Gourley, Tania S; Holm, Teresa M; Heng, Henry H Q; Shivdasani, Ramesh A; Ahmed, Rafi; Andrews, Nancy C; Blank, Volker

    2004-04-01

    Cap'n'collar (CNC) family basic leucine zipper transcription factors play crucial roles in the regulation of mammalian gene expression and development. To determine the in vivo function of the CNC protein Nrf3 (NF-E2-related factor 3), we generated mice deficient in this transcription factor. We performed targeted disruption of two Nrf3 exons coding for CNC homology, basic DNA-binding, and leucine zipper dimerization domains. Nrf3 null mice developed normally and revealed no obvious phenotypic differences compared to wild-type animals. Nrf3(-/-) mice were fertile, and gross anatomy as well as behavior appeared normal. The mice showed normal age progression and did not show any apparent additional phenotype during their life span. We observed no differences in various blood parameters and chemistry values. We infected wild-type and Nrf3(-/-) mice with acute lymphocytic choriomeningitis virus and found no differences in these animals with respect to their number of virus-specific CD8 and CD4 T cells as well as their B-lymphocyte response. To determine whether the mild phenotype of Nrf3 null animals is due to functional redundancy, we generated mice deficient in multiple CNC factors. Contrary to our expectations, an absence of Nrf3 does not seem to cause additional lethality in compound Nrf3(-/-)/Nrf2(-/-) and Nrf3(-/-)/p45(-/-) mice. We hypothesize that the role of Nrf3 in vivo may become apparent only after appropriate challenge to the mice.

  18. A transcription factor active on the epidermal growth factor receptor gene

    International Nuclear Information System (INIS)

    Kageyama, R.; Merlino, G.T.; Pastan, I.

    1988-01-01

    The authors have developed an in vitro transcription system for the epidermal growth factor receptor (EGFR) oncogene by using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce EGFR. They found that a nuclear factor, termed EGFR-specific transcription factor (ETF), specifically stimulated EGFR transcription by 5- to 10-fold. In this report, ETF, purified by using sequence-specific oligonucleotide affinity chromatography, is shown by renaturing material eluted from a NaDodSO 4 /polyacrylamide gel to be a protein with a molecular mass of 120 kDa. ETF binds to the promoter region, as measured by DNase I footprinting and gel-mobility-shift assays, and specifically stimulates the transcription of the EGFR gene in a reconstituted in vitro transcription system. These results suggest that ETF could play a role in the overexpression of the cellular oncogene EGFR

  19. Novel Mechanism of Attenuation of LPS-Induced NF-κB Activation by the Heat Shock Protein 90 Inhibitor, 17-N-allylamino-17-demethoxygeldanamycin, in Human Lung Microvascular Endothelial Cells

    Science.gov (United States)

    Thangjam, Gagan S.; Dimitropoulou, Chistiana; Joshi, Atul D.; Barabutis, Nektarios; Shaw, Mary C.; Kovalenkov, Yevgeniy; Wallace, Chistopher M.; Fulton, David J.; Patel, Vijay

    2014-01-01

    Heat shock protein (hsp) 90 inhibition attenuates NF-κB activation and blocks inflammation. However, the precise mechanism of NF-κB regulation by hsp90 in the endothelium is not clear. We investigated the mechanisms of hsp90 inhibition by 17-N-allylamino-17-demethoxygeldanamycin (17-AAG) on NF-κB activation by LPS in primary human lung microvascular endothelial cells. Transcriptional activation of NF-κB was measured by luciferase reporter assay, gene expression by real-time RT-PCR, DNA binding of transcription factors by chromatin immunoprecipitation assay, protein–protein interaction by coimmunoprecipitation/immunoblotting, histone deacetylase (HDAC)/histone acetyltransferase enzyme activity by fluorometry, and nucleosome eviction by partial microccocal DNase digestion. In human lung microvascular endothelial cells, 17-AAG–induced degradation of IKBα was accomplished regardless of the phosphorylation/ubiquitination state of the protein. Hence, 17-AAG did not block LPS-induced NF-κB nuclear translocation and DNA binding activity. Instead, 17-AAG blocked the recruitment of the coactivator, cAMP response element binding protein binding protein, and prevented the assembly of a transcriptionally competent RNA polymerase II complex at the κB elements of the IKBα (an NF-κB–responsive gene) promoter. The effect of LPS on IKBα mRNA expression was associated with rapid deacetylation of histone-H3(Lys9) and a dramatic down-regulation of core histone H3 binding. Even though treatment with an HDAC inhibitor produced the same effect as hsp90 inhibition, the effect of 17-AAG was independent of HDAC. We conclude that hsp90 inhibition attenuates NF-κB transcriptional activation by preventing coactivator recruitment and nucleosome eviction from the target promoter in human lung endothelial cells. PMID:24303801

  20. Gadd153 and NF-κB crosstalk regulates 27-hydroxycholesterol-induced increase in BACE1 and β-amyloid production in human neuroblastoma SH-SY5Y cells.

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    Gurdeep Marwarha

    Full Text Available β-amyloid (Aβ peptide, accumulation of which is a culprit for Alzheimer's disease (AD, is derived from the initial cleavage of amyloid precursor protein by the aspartyl protease BACE1. Identification of cellular mechanisms that regulate BACE1 production is of high relevance to the search for potential disease-modifying therapies that inhibit BACE1 to reduce Aβ accumulation and AD progression. In the present study, we show that the cholesterol oxidation product 27-hydroxycholesterol (27-OHC increases BACE1 and Aβ levels in human neuroblastoma SH-SY5Y cells. This increase in BACE1 involves a crosstalk between the two transcription factors NF-κB and the endoplasmic reticulum stress marker, the growth arrest and DNA damage induced gene-153 (gadd153, also called CHOP. We specifically show that 27-OHC induces a substantial increase in NF-κB binding to the BACE1 promoter and subsequent increase in BACE1 transcription and Aβ production. The NF-κB inhibitor, sc514, significantly attenuated the 27-OHC-induced increase in NF-κB-mediated BACE1 expression and Aβ genesis. We further show that the 27-OHC-induced NF-κB activation and increased NF-κB-mediated BACE1 expression is contingent on the increased activation of gadd153. Silencing gadd153 expression with siRNA alleviated the 27-OHC-induced increase in NF-κB activation, NF-κB binding to the BACE1 promoter, and subsequent increase in BACE1 transcription and Aβ production. We also show that increased levels of BACE1 in the triple transgenic mouse model for AD is preceded by gadd153 and NF-κB activation. In summary, our study demonstrates that gadd153 and NF-κB work in concert to regulate BACE1 expression. Agents that inhibit gadd153 activation and subsequent interaction with NF-κB might be promising targets to reduce BACE1 and Aβ overproduction and may ultimately serve as disease-modifying treatments for AD.

  1. NF-κB p50 subunit knockout impairs late LTP and alters long term memory in the mouse hippocampus

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    Oikawa Kensuke

    2012-07-01

    Full Text Available Abstract Background Nuclear factor kappa B (NF-κB is a transcription factor typically expressed with two specific subunits (p50, p65. Investigators have reported that NF-κB is activated during the induction of in vitro long term potentiation (LTP, a paradigm of synaptic plasticity and correlate of memory, suggesting that NF-κB may be necessary for some aspects of memory encoding. Furthermore, NF-κB has been implicated as a potential requirement in behavioral tests of memory. Unfortunately, very little work has been done to explore the effects of deleting specific NF-κB subunits on memory. Studies have shown that NF-κB p50 subunit deletion (p50−/− leads to memory deficits, however some recent studies suggest the contrary where p50−/− mice show enhanced memory in the Morris water maze (MWM. To more critically explore the role of the NF-κB p50 subunit in synaptic plasticity and memory, we assessed long term spatial memory in vivo using the MWM, and synaptic plasticity in vitro utilizing high frequency stimuli capable of eliciting LTP in slices from the hippocampus of NF-κB p50−/− versus their controls (p50+/+. Results We found that the lack of the NF-κB p50 subunit led to significant decreases in late LTP and in selective but significant alterations in MWM tests (i.e., some improvements during acquisition, but deficits during retention. Conclusions These results support the hypothesis that the NF-κ p50 subunit is required in long term spatial memory in the hippocampus.

  2. Andrographolide protects against LPS-induced acute lung injury by inactivation of NF-κB.

    Directory of Open Access Journals (Sweden)

    Tao Zhu

    Full Text Available Nuclear factor-κB (NF-κB is a central transcriptional factor and a pleiotropic regulator of many genes involved in acute lung injury. Andrographolide is found in the plant of Andrographis paniculata and widely used in Traditional Chinese Medicine, exhibiting potently anti-inflammatory property by inhibiting NF-κB activity. The purpose of our investigation was designed to reveal the effect of andrographolide on various aspects of LPS induced inflammation in vivo and in vitro.In vivo, BALB/C mice were subjected to LPS injection with or without andrographolide treatments to induce ALI model. In vitro, MLE-12 cells were stimulated with LPS in the presence and absence of andrographolide. In vivo, pulmonary inflammation, pulmonary edema, ultrastructure changes of type II alveolar epithelial cells, MPO activity, total cells, neutrophils, macrophages, TNF-α, IL-6 and IL-1β in BALF, along with the expression of VCAM-1 and VEGF were dose-dependently attenuated by andrographolide. Meanwhile, in vitro, the expression of VCAM-1 and VEGF was also reduced by andrographolide. Moreover, our data showed that andrographolide significantly inhibited the ratios of phospho-IKKβ/total IKKβ, phospho-IκBα/total IκBα and phospho-NF-κB p65/total NF-κB p65, and NF-κB p65 DNA binding activities, both in vivo and in vitro.These results indicate that andrographolide dose-dependently suppressed the severity of LPS-induced ALI, more likely by virtue of andrographolide-mediated NF-κB inhibition at the level of IKKβ activation. These results suggest andrographolide may be considered as an effective and safe drug for the potential treatment of ALI.

  3. Andrographolide Protects against LPS-Induced Acute Lung Injury by Inactivation of NF-κB

    Science.gov (United States)

    Zhu, Tao; Wang, Dao-xin; Zhang, Wei; Liao, Xiu-qing; Guan, Xian; Bo, Hong; Sun, Jia-yang; Huang, Ni-wen; He, Jing; Zhang, Yun-kun; Tong, Jing; Li, Chang-yi

    2013-01-01

    Background Nuclear factor-κB (NF-κB) is a central transcriptional factor and a pleiotropic regulator of many genes involved in acute lung injury. Andrographolide is found in the plant of Andrographis paniculata and widely used in Traditional Chinese Medicine, exhibiting potently anti-inflammatory property by inhibiting NF-κB activity. The purpose of our investigation was designed to reveal the effect of andrographolide on various aspects of LPS induced inflammation in vivo and in vitro. Methods and Results In vivo, BALB/C mice were subjected to LPS injection with or without andrographolide treatments to induce ALI model. In vitro, MLE-12 cells were stimulated with LPS in the presence and absence of andrographolide. In vivo, pulmonary inflammation, pulmonary edema, ultrastructure changes of type II alveolar epithelial cells, MPO activity, total cells, neutrophils, macrophages, TNF-α, IL-6 and IL-1β in BALF, along with the expression of VCAM-1 and VEGF were dose-dependently attenuated by andrographolide. Meanwhile, in vitro, the expression of VCAM-1 and VEGF was also reduced by andrographolide. Moreover, our data showed that andrographolide significantly inhibited the ratios of phospho-IKKβ/total IKKβ, phospho-IκBα/total IκBα and phospho-NF-κB p65/total NF-κB p65, and NF-κB p65 DNA binding activities, both in vivo and in vitro. Conclusions These results indicate that andrographolide dose-dependently suppressed the severity of LPS-induced ALI, more likely by virtue of andrographolide-mediated NF-κB inhibition at the level of IKKβ activation. These results suggest andrographolide may be considered as an effective and safe drug for the potential treatment of ALI. PMID:23437127

  4. Curcumin modulates cellular AP-1, NF-kB, and HPV16 E6 proteins in oral cancer.

    Science.gov (United States)

    Mishra, Alok; Kumar, Rakesh; Tyagi, Abhishek; Kohaar, Indu; Hedau, Suresh; Bharti, Alok C; Sarker, Subhodeep; Dey, Dipankar; Saluja, Daman; Das, Bhudev

    2015-01-01

    In this study, we investigated the effects of the natural antioxidant curcumin on the HPV16-positive oral carcinoma cell line 93VU147T and demonstrated that curcumin is not only a potent inhibitor for the activity of host nuclear transcription factors AP-1 and NF-kB but it also selectively suppresses transcription of the HPV16/E6 oncogene during the carcinogenic process in oral cancer cells. This study suggests a therapeutic potential of curcumin for high-risk human papilloma virus (HPV)-infected oral cancers.

  5. Classical NF-κB Metabolically Reprograms Sarcoma Cells Through Regulation of Hexokinase 2

    Directory of Open Access Journals (Sweden)

    Priya Londhe

    2018-04-01

    Full Text Available BackgroundMetabolic reprogramming has emerged as a cancer hallmark, and one of the well-known cancer-associated metabolic alterations is the increase in the rate of glycolysis. Recent reports have shown that both the classical and alternative signaling pathways of nuclear factor κB (NF-κB play important roles in controlling the metabolic profiles of normal cells and cancer cells. However, how these signaling pathways affect the metabolism of sarcomas, specifically rhabdomyosarcoma (RMS and osteosarcoma (OS, has not been characterized.MethodsClassical NF-κB activity was inhibited through overexpression of the IκBα super repressor of NF-κB in RMS and OS cells. Global gene expression analysis was performed using Affymetrix GeneChip Human Transcriptome Array 2.0, and data were interpreted using gene set enrichment analysis. Seahorse Bioscience XFe24 was used to analyze oxygen consumption rate as a measure of aerobic respiration.ResultsInhibition of classical NF-κB activity in sarcoma cell lines restored alternative signaling as well as an increased oxidative respiratory metabolic phenotype in vitro. In addition, microarray analysis indicated that inhibition of NF-κB in sarcoma cells reduced glycolysis. We showed that a glycolytic gene, hexokinase (HK 2, is a direct NF-κB transcriptional target. Knockdown of HK2 shifted the metabolic profile in sarcoma cells away from aerobic glycolysis, and re-expression of HK2 rescued the metabolic shift induced by inhibition of NF-κB activity in OS cells.ConclusionThese findings suggest that classical signaling of NF-κB plays a crucial role in the metabolic profile of pediatric sarcomas potentially through the regulation of HK2.

  6. [Prostate specific antigen and NF-kB in prostatic disease: relation with malignancy].

    Science.gov (United States)

    Cansino, J R; Vera, R; Rodríguez de Bethencourt, F; Bouraoui, Y; Rodríguez, G; Prieto, A; de la Peña, J; Paniagua, R; Royuela, M

    2011-01-01

    NF-kB (p50/p65) is a transcription factor involved in TNF-α-induced cell death resistance by promoting several antiapoptotic genes. We intend to relate the expression of NF-kB (p50 and p65) with serum levels of prostate-specific antigen (PSA), both in normal males and in those with pathologic conditions of the prostate. this study was carried out in 5 normal, 24 benign prostatic hyperplastic (BPH) and 19 patients with prostate cancer (PC). Immunohistochemical and Western blot analyses were performed on tissue and serum PSA was assayed by PSA DPC Immulite assays (Diagnostics Products Corporation, Los Angeles, CA). in controls, p65 NF-kB was not found and p50 was scantly detected in 60% normal samples in the cytoplasm of epithelial cells. Both p50 and p65 were expressed in 62.5% of the samples with BPH and in 63.2% of those with PC. Both increased its frequency of expression with higher PSA serum levels. Activation of NF-kB revealed by its nuclear translocation in prostate cancer could be related to cancer progression and elevated seric PSA levels. A better understanding of the biologic mechanism by which circulating PSA levels increase and its relation with NF-kB expression is needed. Possibly, NF-kB blockage could be used as a therapeutic target to counteract proliferation in prostate cancer. Copyright © 2010 AEU. Published by Elsevier Espana. All rights reserved.

  7. Vorinostat, a HDAC inhibitor, showed anti-osteoarthritic activities through inhibition of iNOS and MMP expression, p38 and ERK phosphorylation and blocking NF-κB nuclear translocation.

    Science.gov (United States)

    Zhong, Hui-ming; Ding, Qian-hai; Chen, Wei-ping; Luo, Ru-bin

    2013-10-01

    Overproduction of nitric oxide (NO) and matrix metalloproteinases (MMPs) plays an important role in the pathogenesis of osteoarthritis (OA). In present study, we investigated whether vorinostat can inhibit the catabolic effects of IL-1β in vitro, especially the inhibition of MMPs and inducible nitric oxide synthase (iNOS) through the attenuation of nuclear factor kappa-B (NF-κB) and mitogen activated protein kinase (MAPK) pathways in human chondrocytes. Human OA chondrocytes were either left untreated or treated with various concentrations of vorinostat followed by incubation with IL-1β (5ng/mL). Effects of vorinostat on IL-1β-induced gene and protein expression of iNOS, MMP-1, MMP-13 and tissue inhibitors of metalloproteinase-1 (TIMP-1) were verified by quantitative real time-PCR and Western blot analysis. Production of NO, MMP-1, MMP-13 and TIMP-1 released in culture supernatant was estimated using commercially available kits. The roles of NF-κB and MAPK pathways in the regulation of targeted genes and the mechanism involved in vorinostat mediated modulation of these genes were determined by Western blot using specific antibodies. We found that vorinostat down-regulated iNOS, MMP-1 and MMP-13 expression and up-regulated TIMP-1 expression in human OA chondrocytes. In addition, the release of NO, MMP-1 and MMP-13 secreted from IL-1β stimulated chondrocytes was also suppressed by vorinostat. Interestingly, vorinostat selectively inhibited IL-1β-induced p38 and ERK1/2 activation without affecting JNK activation. Furthermore, we observed that vorinostat inhibited NF-κB pathway by suppressing the degradation of I-κBα and attenuating NF-κB p65 translocation to the nucleus. These results suggest that vorinostat may be a promising therapeutic agent for the prevention and treatment of OA. © 2013.

  8. Lentiviral-mediated Targeted NF-κB Blockade in Dorsal Spinal Cord Glia Attenuates Sciatic Nerve Injury-induced Neuropathic Pain in the Rat.

    Science.gov (United States)

    Meunier, Alice; Latrémolière, Alban; Dominguez, Elisa; Mauborgne, Annie; Philippe, Stéphanie; Hamon, Michel; Mallet, Jacques; Benoliel, Jean-Jacques; Pohl, Michel

    2007-04-01

    Neuropathic pain developing after peripheral nerve injury is associated with altered neuronal and glial cell functions in the spinal cord. Activated glia produces algogenic mediators, exacerbating pain. Among the different intracellular pathways possibly involved in the modified glial function, the nuclear factor κB (NF-κB) system is of particular interest, as numerous genes encoding inflammation- and pain-related molecules are controlled by this transcription factor. NF-κB is a pleiotropic factor also involved in central nervous system homeostasy. To study its role in chronic pain, it is thus essential to inhibit the NF-κB pathway selectively in activated spinal glial cells. Here, we show that when restricted to spinal cord and targeted to glial cells, lentiviral vector-mediated delivery of NF-κB super- repressor IκBα resulted in an inhibition of the NF-κB pathway activated in the rat spinal cord after sciatic nerve injury (chronic constriction injury, CCI). Concomitantly, IκBα overproduction prevented the enhanced expression of interleukin-6 and of inducible nitric oxide synthase associated with chronic constriction injury and resulted in prolonged antihyperalgesic and antiallodynic effects. These data show that targeted blockade of NF-κB activity in spinal glia efficiently alleviates pain behavior in CCI rats, demonstrating the active participation of the glial NF-κB pathway in the development of neuropathic pain after peripheral nerve injury. Copyright © 2007 The American Society of Gene Therapy. Published by Elsevier Inc. All rights reserved.

  9. DNA residence time is a regulatory factor of transcription repression

    Science.gov (United States)

    Clauß, Karen; Popp, Achim P.; Schulze, Lena; Hettich, Johannes; Reisser, Matthias; Escoter Torres, Laura; Uhlenhaut, N. Henriette

    2017-01-01

    Abstract Transcription comprises a highly regulated sequence of intrinsically stochastic processes, resulting in bursts of transcription intermitted by quiescence. In transcription activation or repression, a transcription factor binds dynamically to DNA, with a residence time unique to each factor. Whether the DNA residence time is important in the transcription process is unclear. Here, we designed a series of transcription repressors differing in their DNA residence time by utilizing the modular DNA binding domain of transcription activator-like effectors (TALEs) and varying the number of nucleotide-recognizing repeat domains. We characterized the DNA residence times of our repressors in living cells using single molecule tracking. The residence times depended non-linearly on the number of repeat domains and differed by more than a factor of six. The factors provoked a residence time-dependent decrease in transcript level of the glucocorticoid receptor-activated gene SGK1. Down regulation of transcription was due to a lower burst frequency in the presence of long binding repressors and is in accordance with a model of competitive inhibition of endogenous activator binding. Our single molecule experiments reveal transcription factor DNA residence time as a regulatory factor controlling transcription repression and establish TALE-DNA binding domains as tools for the temporal dissection of transcription regulation. PMID:28977492

  10. Akt-dependent NF-κB activation is required for bile acids to rescue colon cancer cells from stress-induced apoptosis

    International Nuclear Information System (INIS)

    Shant, Jasleen; Cheng, Kunrong; Marasa, Bernard S.; Wang Jianying; Raufman, Jean-Pierre

    2009-01-01

    Conjugated secondary bile acids promote human colon cancer cell proliferation by activating EGF receptors (EGFR). We hypothesized that bile acid-induced EGFR activation also mediates cell survival by downstream Akt-regulated activation of NF-κB. Deoxycholyltaurine (DCT) treatment attenuated TNF-α-induced colon cancer cell apoptosis, and stimulated rapid and sustained NF-κB nuclear translocation and transcriptional activity (detected by NF-κB binding to an oligonucleotide consensus sequence and by activation of luciferase reporter gene constructs). Both DCT-induced NF-κB nuclear translocation and attenuation of TNF-α-stimulated apoptosis were dependent on EGFR activation. Inhibitors of nuclear translocation, proteosome activity, and IκBα kinase attenuated NF-κB transcriptional activity. Cell transfection with adenoviral vectors encoding a non-degradable IκBα 'super-repressor' blocked the actions of DCT on both NF-κB activation and TNF-α-induced apoptosis. Likewise, transfection with mutant akt and treatment with a chemical inhibitor of Akt attenuated effects of DCT on NF-κB transcriptional activity and TNF-α-induced apoptosis. Chemical inhibitors of Akt and NF-κB activation also attenuated DCT-induced rescue of H508 cells from ultraviolet radiation-induced apoptosis. Collectively, these observations indicate that, downstream of EGFR, bile acid-induced colon cancer cell survival is mediated by Akt-dependent NF-κB activation. These findings provide a mechanism whereby bile acids increase resistance of colon cancer to chemotherapy and radiation

  11. Protective role of benfotiamine, a fat-soluble vitamin B1 analogue, in lipopolysaccharide-induced cytotoxic signals in murine macrophages.

    Science.gov (United States)

    Yadav, Umesh C S; Kalariya, Nilesh M; Srivastava, Satish K; Ramana, Kota V

    2010-05-15

    This study was designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of vitamin B1, affects lipopolysaccharide (LPS)-induced inflammatory signals leading to cytotoxicity in the mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of the Bcl-2 family of proapoptotic proteins, caspase-3 activation, and PARP cleavage and altered mitochondrial membrane potential and release of cytochrome c and apoptosis-inducing factor and phosphorylation and subsequent activation of p38-MAPK, stress-activated kinases (SAPK/JNK), protein kinase C, and cytoplasmic phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappaB and consequent activation and nuclear translocation of the redox-sensitive transcription factor NF-kappaB were significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and the inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE(2) was also blocked significantly. Thus, our results elucidate the molecular mechanism of the anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophages. Benfotiamine suppresses oxidative stress-induced NF-kappaB activation and prevents bacterial endotoxin-induced inflammation, indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Cadmium induces cytotoxicity in human bronchial epithelial cells through upregulation of eIF5A1 and NF-kappaB

    Energy Technology Data Exchange (ETDEWEB)

    Chen, De-Ju; Xu, Yan-Ming; Du, Ji-Ying [Laboratory of Cancer Biology and Epigenetics, Shantou University Medical College, Shantou, Guangdong 515041 (China); Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong 515041 (China); Huang, Dong-Yang [Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong 515041 (China); Lau, Andy T.Y., E-mail: andytylau@stu.edu.cn [Laboratory of Cancer Biology and Epigenetics, Shantou University Medical College, Shantou, Guangdong 515041 (China); Department of Cell Biology and Genetics, Shantou University Medical College, Shantou, Guangdong 515041 (China)

    2014-02-28

    Highlights: • Normal human bronchial epithelial cells (BEAS-2B) were dosed with cadmium (Cd). • A low level (2 μM) of Cd treatment for 36 h elicited negligible cytotoxicity. • High levels (20 or 30 μM) of Cd treatment for 36 h induced cell death. • High levels of Cd can upregulate the protein levels of eIF5A1 and NF-κB p65. • We suggest that eIF5A1 level is possibly modulated by NF-κB. - Abstract: Cadmium (Cd) and Cd compounds are widely-distributed in the environment and well-known carcinogens. Here, we report that in CdCl{sub 2}-exposed human bronchial epithelial cells (BEAS-2B), the level of p53 is dramatically decreased in a time- and dose-dependent manner, suggesting that the observed Cd-induced cytotoxicity is not likely due to the pro-apoptotic function of p53. Therefore, this prompted us to further study the responsive pro-apoptotic factors by proteomic approaches. Interestingly, we identified that high levels (20 or 30 μM) of Cd can significantly upregulate the protein levels of eukaryotic translation initiation factor 5A1 (eIF5A1) and redox-sensitive transcription factor NF-κB p65. Moreover, there is an enhanced NF-κB nuclear translocation as well as chromatin-binding in Cd-treated BEAS-2B cells. We also show that small interfering RNA-specific knockdown of eIF5A1 in Cd-exposed cells attenuated the Cd cytotoxicity, indicating the potential role of eIF5A1 in Cd cytotoxicity. As eIF5A1 is reported to be related with cell apoptosis but little is known about its transcriptional control, we hypothesize that NF-κB might likely modulate eIF5A1 gene expression. Notably, by bioinformatic analysis, several potential NF-κB binding sites on the upstream promoter region of eIF5A1 gene can be found. Subsequent chromatin immunoprecipitation assay revealed that indeed there is enhanced NF-κB binding on eIF5A1 promoter region of Cd-treated BEAS-2B cells. Taken together, our findings suggest for the first time a regulatory mechanism for the pro

  13. Inhibition of Nuclear Transcription Factor-κB and Activation of Peroxisome Proliferator-Activated Receptors in HepG2 Cells by Cucurbitane-Type Triterpene Glycosides from Momordica charantia

    Science.gov (United States)

    Nhiem, Nguyen Xuan; Yen, Pham Hai; Ngan, Nguyen Thi Thanh; Quang, Tran Hong; Kiem, Phan Van; Minh, Chau Van; Tai, Bui Huu; Cuong, Nguyen Xuan; Song, Seok Bean

    2012-01-01

    Abstract Momordica charantia: is used to treat various diseases, including inflammatory conditions. Previous reports indicated that the extract of this plant inhibits activation of nuclear transcription factor-κB (NF-κB) but activates peroxisome proliferator-activated receptor (PPAR). Additionally, cucurbitane-type triterpene glycosides are the main bioactive components of the fruit of M. charantia. Therefore, we investigated the anti-inflammatory activity of 17 cucurbitane-type triterpene glycosides (1–17) isolated from this plant. Their inhibition of NF-κB and activation of PPAR activities in HepG2 cells were measured using luciferase reporter and PPAR subtype transactivation assays. Compounds 6 and 8 were found to inhibit NF-κB activation stimulated by tumor necrosis factor-α (TNFα) in a dose-dependent manner. With 50% inhibition concentration (IC50) values of 0.4 μM, compounds 6 and 8 were more potent inhibitors than the positive control, sulfasalazine (IC50=0.9 μM). Compounds 4, 6, and 8 also inhibited TNFα-induced expressions of inducible nitric oxide synthase and cyclooxygenase-2 mRNA. However, only compound 13 significantly increased PPARγ transactivation. PMID:22248180

  14. Fisetin Imparts Neuroprotection in Experimental Diabetic Neuropathy by Modulating Nrf2 and NF-κB Pathways.

    Science.gov (United States)

    Sandireddy, Reddemma; Yerra, Veera Ganesh; Komirishetti, Prashanth; Areti, Aparna; Kumar, Ashutosh

    2016-08-01

    The current study is aimed to assess the therapeutic potential of fisetin, a phytoflavonoid in streptozotocin (STZ)-induced experimental diabetic neuropathy (DN) in rats. Fisetin was administered (5 and 10 mg/kg) for 2 weeks (7th and 8th week) post STZ administration. Thermal and mechanical hyperalgesia were assessed by measuring tactile sensitivity to thermal and mechanical stimuli, respectively. Motor nerve conduction velocity (MNCV) was determined using power lab system and sciatic nerve blood flow (NBF) was determined using laser Doppler system. Nerve sections were processed for TUNEL assay and NF-κB, COX-2 immunohistochemical staining. Sciatic nerve homogenate was used for biochemical and Western blotting analysis. MNCV and sciatic NBF deficits associated with DN were ameliorated in fisetin administered rats. Fisetin treatment reduced the interleukin-6 and tumour necrosis factor-alpha in sciatic nerves of diabetic rats (p < 0.001). Protein expression studies have identified that the therapeutic benefit of fisetin might be through regulation of redox sensitive transcription factors such as nuclear erythroid 2-related factor 2 (Nrf2) and nuclear factor kappa B (NF-κB). Our study provides an evidence for the therapeutic potential of fisetin in DN through simultaneous targeting of NF-κB and Nrf2.

  15. Runx transcription factors in neuronal development

    Directory of Open Access Journals (Sweden)

    Shiga Takashi

    2008-08-01

    Full Text Available Abstract Runt-related (Runx transcription factors control diverse aspects of embryonic development and are responsible for the pathogenesis of many human diseases. In recent years, the functions of this transcription factor family in the nervous system have just begun to be understood. In dorsal root ganglion neurons, Runx1 and Runx3 play pivotal roles in the development of nociceptive and proprioceptive sensory neurons, respectively. Runx appears to control the transcriptional regulation of neurotrophin receptors, numerous ion channels and neuropeptides. As a consequence, Runx contributes to diverse aspects of the sensory system in higher vertebrates. In this review, we summarize recent progress in determining the role of Runx in neuronal development.

  16. Homeostatic NF-κB Signaling in Steady-State Migratory Dendritic Cells Regulates Immune Homeostasis and Tolerance.

    Science.gov (United States)

    Baratin, Myriam; Foray, Chloe; Demaria, Olivier; Habbeddine, Mohamed; Pollet, Emeline; Maurizio, Julien; Verthuy, Christophe; Davanture, Suzel; Azukizawa, Hiroaki; Flores-Langarica, Adriana; Dalod, Marc; Lawrence, Toby

    2015-04-21

    Migratory non-lymphoid tissue dendritic cells (NLT-DCs) transport antigens to lymph nodes (LNs) and are required for protective immune responses in the context of inflammation and to promote tolerance to self-antigens in steady-state. However, the molecular mechanisms that elicit steady-state NLT-DC maturation and migration are unknown. By comparing the transcriptome of NLT-DCs in the skin with their migratory counterparts in draining LNs, we have identified a novel NF-κB-regulated gene network specific to migratory DCs. We show that targeted deletion of IKKβ in DCs, a major activator of NF-κB, prevents NLT-DC accumulation in LNs and compromises regulatory T cell conversion in vivo. This was associated with impaired tolerance and autoimmunity. NF-κB is generally considered the prototypical pro-inflammatory transcription factor, but this study describes a role for NF-κB signaling in DCs for immune homeostasis and tolerance that could have implications in autoimmune diseases and immunity. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. A noncanonical Flt3ITD/NF-κB signaling pathway represses DAPK1 in acute myeloid leukemia.

    Science.gov (United States)

    Shanmugam, Rajasubramaniam; Gade, Padmaja; Wilson-Weekes, Annique; Sayar, Hamid; Suvannasankha, Attaya; Goswami, Chirayu; Li, Lang; Gupta, Sushil; Cardoso, Angelo A; Baghdadi, Tareq Al; Sargent, Katie J; Cripe, Larry D; Kalvakolanu, Dhananjaya V; Boswell, H Scott

    2012-01-15

    Death-associated protein kinase 1 (DAPK1), a tumor suppressor, is a rate-limiting effector in an endoplasmic reticulum (ER) stress-dependent apoptotic pathway. Its expression is epigenetically suppressed in several tumors. A mechanistic basis for epigenetic/transcriptional repression of DAPK1 was investigated in certain forms of acute myeloid leukemia (AML) with poor prognosis, which lacked ER stress-induced apoptosis. Heterogeneous primary AMLs were screened to identify a subgroup with Flt3ITD in which repression of DAPK1, among NF-κB-and c-Jun-responsive genes, was studied. RNA interference knockdown studies were carried out in an Flt3ITD(+) cell line, MV-4-11, to establish genetic epistasis in the pathway Flt3ITD-TAK1-DAPK1 repression, and chromatin immunoprecipitations were carried out to identify proximate effector proteins, including TAK1-activated p52NF-κB, at the DAPK1 locus. AMLs characterized by normal karyotype with Flt3ITD were found to have 10- to 100-fold lower DAPK1 transcripts normalized to the expression of c-Jun, a transcriptional activator of DAPK1, as compared with a heterogeneous cytogenetic category. In addition, Meis1, a c-Jun-responsive adverse AML prognostic gene signature was measured as control. These Flt3ITD(+) AMLs overexpress relB, a transcriptional repressor, which forms active heterodimers with p52NF-κB. Chromatin immunoprecipitation assays identified p52NF-κB binding to the DAPK1 promoter together with histone deacetylase 2 (HDAC2) and HDAC6 in the Flt3ITD(+) human AML cell line MV-4-11. Knockdown of p52NF-κB or its upstream regulator, NF-κB-inducing kinase (NIK), de-repressed DAPK1. DAPK1-repressed primary Flt3ITD(+) AMLs had selective nuclear activation of p52NF-κB. Flt3ITD promotes a noncanonical pathway via TAK1 and p52NF-κB to suppress DAPK1 in association with HDACs, which explains DAPK1 repression in Flt3ITD(+) AML. ©2011 AACR.

  18. Time- and cell-resolved dynamics of redox-sensitive Nrf2, HIF and NF-κB activities in 3D spheroids enriched for cancer stem cells

    Directory of Open Access Journals (Sweden)

    Anna P. Kipp

    2017-08-01

    Full Text Available Cancer cells have an altered redox status, with changes in intracellular signaling pathways. The knowledge of how such processes are regulated in 3D spheroids, being well-established tumor models, is limited. To approach this question we stably transfected HCT116 cells with a pTRAF reporter that enabled time- and cell-resolved activity monitoring of three redox-regulated transcription factors Nrf2, HIF and NF-κB in spheroids enriched for cancer stem cells. At the first day of spheroid formation, these transcription factors were activated and thereafter became repressed. After about a week, both HIF and Nrf2 were reactivated within the spheroid cores. Further amplifying HIF activation in spheroids by treatment with DMOG resulted in a dominant quiescent stem-cell-like phenotype, with high resistance to stress-inducing treatments. Auranofin, triggering oxidative stress and Nrf2 activation, had opposite effects with increased differentiation and proliferation. These novel high-resolution insights into spatiotemporal activation patterns demonstrate a striking coordination of redox regulated transcription factors within spheroids not occurring in conventional cell culture models. Keywords: Redox regulation, Cancer stem cells, Spheroids, Nrf2, HIF, NF-κB

  19. NIK and IKKbeta interdependence in NF-kappaB signalling--flux analysis of regulation through metabolites.

    Science.gov (United States)

    Kim, Hong-Bum; Evans, Iona; Smallwood, Rod; Holcombe, Mike; Qwarnstrom, Eva E

    2010-02-01

    Activation of the transcription factor NF-kappaB is central to control of immune and inflammatory responses. Cytokine induced activation through the classical or canonical pathway relies on degradation of the inhibitor, IkappaBalpha and regulation by the IKKbeta kinase. In addition, the NF-kappaB is activated through the NF-kappaB-inducing kinase, NIK. Analysis of the IKK/NIK inter-relationship and its impact on NF-kappaB control, were analysed by mathematical modelling, using matrix formalism and stoichiometrically balanced reactions. The analysis considered a range of bio-reactions and core metabolites and their role in relation to kinase activation and in control of specific steps of the NF-kappaB pathway. The model predicts a growth-rate and time-dependent transfer of the primary kinase activity from IKKbeta to NIK. In addition, it suggests that NIK/IKKbeta interdependence is controlled by intermediates of phosphoribosylpyrophosphate (PRPP) within the glycolysis pathway, and thus, identifies a link between specific metabolic events and kinase activation in inflammatory signal transduction. Subsequent in vitro experiments, carried out to validate the impact of IKK/NIK interdependence, confirmed signal amplification at the level of the NF-kappaB/IkappaBalpha complex control in the presence of both kinases. Further, they demonstrate that the induced potentiation is due to synergistic enhancement of relA-dependent activation. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  20. NF-κB suppresses HIF-1α response by competing for P300 binding

    International Nuclear Information System (INIS)

    Mendonca, Daniela B.S.; Mendonca, Gustavo; Aragao, Francisco J.L.; Cooper, Lyndon F.

    2011-01-01

    Research highlights: → p65 completely blocked HIF-1α activity at the HRE on different cell lines. → p65 caused minor changes in HIF-1α and HIF-1α target genes mRNA expression. → p65 reduced transcription of VEGF promoter. → p65 competes with HIF-1α for p300. -- Abstract: Hypoxia has emerged as a key determinant of osteogenesis. HIF-1α is the transcription factor mediating hypoxia responses that include induction of VEGF and related bone induction. Inflammatory signals antagonize bone repair via the NF-κB pathway. The present investigation explored the functional relationship of hypoxia (HIF-1α function) and inflammatory signaling (NF-κB) in stem like and osteoprogenitor cell lines. The potential interaction between HIF-1α and NF-κB signaling was explored by co-transfection studies in hFOB with p65, HIF-1α and 9x-HRE-luc or HIF-1α target genes reporter plasmids. Nuclear cross-talk was directly tested using the mammalian Gal4/VP16 two-hybrid, and confirmed by co-immunoprecipitation/western blotting assays. The results show that inflammatory stimulation (TNF-α treatment) causes a marked inhibition of HIF-1α function at the HRE in all cell lines studied. Also, co-transfection with p65 expression vector leads to reduced hVEGFp transcription after DFO-induced hypoxia. However, TNF-α treatment had little effect on HIF-1α mRNA levels. The functional interaction of Gal4-HIF-1α and VP16-p300 fusion proteins is effectively blocked by expression of p65 in a dose dependent manner. It was concluded that NF-κB-mediated inflammatory signaling is able to block HIF-1α transactivation at HRE-encoding genes by direct competition for p300 binding at the promoter. Inflammation may influence the stem cell niche and tissue regeneration by influencing cellular responses to hypoxia.

  1. Molecular Interactions between NR4A Orphan Nuclear Receptors and NF-κB Are Required for Appropriate Inflammatory Responses and Immune Cell Homeostasis.

    Science.gov (United States)

    Murphy, Evelyn P; Crean, Daniel

    2015-06-29

    Appropriate innate and adaptive immune responses are essential for protection and resolution against chemical, physical or biological insults. Immune cell polarization is fundamental in orchestrating distinct phases of inflammation, specifically acute phase responses followed by resolution and tissue repair. Dysregulation of immune cell and inflammatory responses is a hallmark of multiple diseases encompassing atherosclerosis, rheumatoid arthritis, psoriasis and metabolic syndromes. A master transcriptional mediator of diverse inflammatory signaling and immune cell function is NF-κB, and altered control of this key regulator can lead to an effective switch from acute to chronic inflammatory responses. Members of the nuclear receptor (NR) superfamily of ligand-dependent transcription factors crosstalk with NF-κB to regulate immune cell function(s). Within the NR superfamily the NR4A1-3 orphan receptors have emerged as important regulators of immune cell polarization and NF-κB signaling. NR4A receptors modulate NF-κB activity in a dynamic fashion, either repressing or enhancing target gene expression leading to altered inflammatory outcome. Here we will discuss the pivotal role NR4A's receptors play in orchestrating immune cell homeostasis through molecular crosstalk with NF-κB. Specifically, we will examine such NR4A/NF-κB interactions within the context of distinct cell phenotypes, including monocyte, macrophage, T cells, endothelial, and mesenchymal cells, which play a role in inflammation-associated disease. Finally, we review the therapeutic potential of altering NR4A/NF-κB interactions to limit hyper-inflammatory responses in vivo.

  2. Potential Role of Activating Transcription Factor 5 during Osteogenesis

    Directory of Open Access Journals (Sweden)

    Luisa Vicari

    2016-01-01

    Full Text Available Human adipose-derived stem cells are an abundant population of stem cells readily isolated from human adipose tissue that can differentiate into connective tissue lineages including bone, cartilage, fat, and muscle. Activating transcription factor 5 is a transcription factor of the ATF/cAMP response element-binding protein (CREB family. It is transcribed in two types of mRNAs (activating transcription factor 5 isoform 1 and activating transcription factor 5 isoform 2, encoding the same single 30-kDa protein. Although it is well demonstrated that it regulates the proliferation, differentiation, and apoptosis, little is known about its potential role in osteogenic differentiation. The aim of this study was to evaluate the expression levels of the two isoforms and protein during osteogenic differentiation of human adipose-derived stem cells. Our data indicate that activating transcription factor 5 is differentially expressed reaching a peak of expression at the stage of bone mineralization. These findings suggest that activating transcription factor 5 could play an interesting regulatory role during osteogenesis, which would provide a powerful tool to study bone physiology.

  3. Potential Role of Activating Transcription Factor 5 during Osteogenesis.

    Science.gov (United States)

    Vicari, Luisa; Calabrese, Giovanna; Forte, Stefano; Giuffrida, Raffaella; Colarossi, Cristina; Parrinello, Nunziatina Laura; Memeo, Lorenzo

    2016-01-01

    Human adipose-derived stem cells are an abundant population of stem cells readily isolated from human adipose tissue that can differentiate into connective tissue lineages including bone, cartilage, fat, and muscle. Activating transcription factor 5 is a transcription factor of the ATF/cAMP response element-binding protein (CREB) family. It is transcribed in two types of mRNAs (activating transcription factor 5 isoform 1 and activating transcription factor 5 isoform 2), encoding the same single 30-kDa protein. Although it is well demonstrated that it regulates the proliferation, differentiation, and apoptosis, little is known about its potential role in osteogenic differentiation. The aim of this study was to evaluate the expression levels of the two isoforms and protein during osteogenic differentiation of human adipose-derived stem cells. Our data indicate that activating transcription factor 5 is differentially expressed reaching a peak of expression at the stage of bone mineralization. These findings suggest that activating transcription factor 5 could play an interesting regulatory role during osteogenesis, which would provide a powerful tool to study bone physiology.

  4. The effects of Ankaferd® Blood Stopper on transcription factors in HUVEC and the erythrocyte protein profile

    Directory of Open Access Journals (Sweden)

    Erkan Yılmaz

    2011-12-01

    Full Text Available Objective: Ankaferd® Blood Stopper (ABS is an herbal extract that has historically been used as a hemostatic agent in traditional Turkish medicine. ABS is comprised of a standardized herbal mixture of T. vulgaris, G. glabra, V. vinifera, A. officinarum, and U. dioica. ABS’s basic mechanism of action is the formation of an encapsulated protein web, which represents the focal point for vital erythrocyte masses. The hemostatic effects of ABS have been observed in vitro and in vivo. ABS was registered as a hemostatic agent for external hemorrhages and dental bleeding following phase I randomized, double-blind crossover placebo-controlled clinical research, and safety and efficacy reports. In terms of the potential use of ABS, transcription factors may be novel factors that play a role in the hemostatic and other pleiotropic effects of ABS. Materials and Methods: Hence, the present study aimed to investigate the effects of ABS on endothelium, and possible transcription factor changes in HUVEC (human umbilical vein endothelial cells and the erythrocyte membrane profile. ABS (5 μL and 50 μL was administered to HUVEC (in 75 cm2; ~75% fullness for 5 min and 15 min. Results: ABS caused significant increases in the level of activation of the following transcription factors; AP2, AR, CRE/ATF1, CREB, E2F1-5, E2F6, EGR, GATA, HNF-1, ISRE, Myc-Max, NF-1, NFkB, p53, PPAR, SMAD 2/3, SP1, TRE/AP1, and YY1. Following erythrocyte membrane isolation, protein complexes were undissolved, but denatured. The protein complex formed was resistant to heat and detergent. Trypsin and sonication were used in order to break this complex; the complex dissolved and erythrocyte membrane proteins were released in SDS-PAGE.Conclusion: ABS established a very fast and solid protein web, and increased the level of transcription factor activation. Therefore the cellular effects of ABS could be related to different intracellular biological pathways.

  5. Immunomodulatory effect of tea saponin in immune T-cells and T-lymphoma cells via regulation of Th1, Th2 immune response and MAPK/ERK2 signaling pathway.

    Science.gov (United States)

    Bhardwaj, Jyoti; Chaudhary, Narendra; Seo, Hyo-Jin; Kim, Min-Yong; Shin, Tai-Sun; Kim, Jong-Deog

    2014-06-01

    The anti-cancer activity of saponins and phenolic compounds present in green tea was previously reported. However, the immunomodulatory and adjuvanticity activity of tea saponin has never been studied. In this study, we investigated the immunomodulatory effect of tea saponin in T-lymphocytes and EL4 cells via regulation of cytokine response and mitogen-activated protein kinases (MAPK) signaling pathway. Quantitative analysis of mRNA expression level of cytokines were performed by reverse transcription polymerase chain reaction following stimulation with tea saponin, ovalbumin (OVA) alone or tea saponin in combination with OVA. Tea saponin inhibited the proliferation of EL4 cells measured in a dose-dependent manner. No cytotoxicity effect of tea saponin was detected in T-lymphocytes; rather, tea saponin enhanced the proliferation of T-lymphocytes. Tea saponin with OVA increased the expression of interleukin (IL)-1, IL-2, IL-12, interferon-γ and tumor necrosis factor (TNF)-α and decreased the expression level of IL-10 and IL-8 in T-lymphocytes. Furthermore, tea saponin, in the presence of OVA, downregulated the MAPK signaling pathway via inhibition of IL-4, IL-8 and nuclear factor kappaB (NF-κB) in EL4 cells. Th1 cytokines enhancer and Th2 cytokines and NF-κB inhibitor, tea saponin can markedly inhibit the proliferation and invasiveness of T-lymphoma (EL4) cells, possibly due to TNF-α- and NF-κB-mediated regulation of MAPK signaling pathway.

  6. SoyDB: a knowledge database of soybean transcription factors

    Directory of Open Access Journals (Sweden)

    Valliyodan Babu

    2010-01-01

    Full Text Available Abstract Background Transcription factors play the crucial rule of regulating gene expression and influence almost all biological processes. Systematically identifying and annotating transcription factors can greatly aid further understanding their functions and mechanisms. In this article, we present SoyDB, a user friendly database containing comprehensive knowledge of soybean transcription factors. Description The soybean genome was recently sequenced by the Department of Energy-Joint Genome Institute (DOE-JGI and is publicly available. Mining of this sequence identified 5,671 soybean genes as putative transcription factors. These genes were comprehensively annotated as an aid to the soybean research community. We developed SoyDB - a knowledge database for all the transcription factors in the soybean genome. The database contains protein sequences, predicted tertiary structures, putative DNA binding sites, domains, homologous templates in the Protein Data Bank (PDB, protein family classifications, multiple sequence alignments, consensus protein sequence motifs, web logo of each family, and web links to the soybean transcription factor database PlantTFDB, known EST sequences, and other general protein databases including Swiss-Prot, Gene Ontology, KEGG, EMBL, TAIR, InterPro, SMART, PROSITE, NCBI, and Pfam. The database can be accessed via an interactive and convenient web server, which supports full-text search, PSI-BLAST sequence search, database browsing by protein family, and automatic classification of a new protein sequence into one of 64 annotated transcription factor families by hidden Markov models. Conclusions A comprehensive soybean transcription factor database was constructed and made publicly accessible at http://casp.rnet.missouri.edu/soydb/.

  7. Radiation activation of transcription factors in mammalian cells

    International Nuclear Information System (INIS)

    Kraemer, M.; Stein, B.; Mai, S.; Kunz, E.; Koenig, H.; Ponta, H.; Herrlich, P.; Rahmsdorf, H.J.; Loferer, H.; Grunicke, H.H.

    1990-01-01

    In mammalian cells radiation induces the enhanced transcription of several genes. The cis acting elements in the control region of inducible genes have been delimited by site directed mutagenesis. Several different elements have been found in different genes. They do not only activate gene transcription in response to radiation but also in response to growth factors and to tumor promoter phorbol esters. The transcription factors binding to these elements are present also in non-irradiated cells, but their DNA binding activity and their transactivating capability is increased upon irradiation. The signal chain linking the primary radiation induced signal (damaged DNA) to the activation of transcription factors involves the action of (a) protein kinase(s). (orig.)

  8. Activation of NF-κB in basolateral amygdala is required for memory reconsolidation in auditory fear conditioning.

    Science.gov (United States)

    Si, Jijian; Yang, Jianli; Xue, Lifen; Yang, Chenhao; Luo, Yixiao; Shi, Haishui; Lu, Lin

    2012-01-01

    Posttraumatic stress disorder (PTSD) is characterized by acute and chronic changes in the stress response, manifested as conditioned fear memory. Previously formed memories that are susceptible to disruption immediately after retrieval undergo a protein synthesis-dependent process to become persistent, termed reconsolidation, a process that is regulated by many distinct molecular mechanisms that control gene expression. Increasing evidence supports the participation of the transcription factor NF-κB in the different phases of memory. Here, we demonstrate that inhibition of NF-κB in the basolateral amygdala (BLA), but not central nucleus of the amygdala, after memory reactivation impairs the retention of amygdala-dependent auditory fear conditioning (AFC). We used two independent pharmacological strategies to disrupt the reconsolidation of AFC. Bilateral intra-BLA infusion of sulfasalazine, an inhibitor of IκB kinase that activates NF-κB, and bilateral intra-BLA infusion of SN50, a direct inhibitor of the NF-κB DNA-binding complex, immediately after retrieval disrupted the reconsolidation of AFC. We also found that systemic pretreatment with sodium butyrate, a histone deacetylase inhibitor that enhances histone acetylation, in the amygdala rescued the disruption of reconsolidation induced by NF-κB inhibition in the BLA. These findings indicate that NF-κB activity in the BLA is required for memory reconsolidation in AFC, suggesting that NF-κB might be a potential pharmacotherapy target for posttraumatic stress disorder.

  9. Canonical and Non-Canonical NF-κB Signaling Promotes Breast Cancer Tumor-Initiating Cells

    Science.gov (United States)

    Kendellen, Megan F.; Bradford, Jennifer W.; Lawrence, Cortney L.; Clark, Kelly S.; Baldwin, Albert S.

    2014-01-01

    Tumor-initiating cells (TICs) are a sub-population of cells that exhibit a robust ability to self-renew and contribute to the formation of primary tumors, the relapse of previously treated tumors, and the development of metastases. TICs have been identified in various tumors, including those of the breast, and are particularly enriched in the basal-like and claudin-low subtypes of breast cancer. The signaling pathways that contribute to the function and maintenance of TICs are under intense study. We explored the potential involvement of the NF-κB family of transcription factors in TICs in cell lines that are representative of basal-like and claudin-low breast cancer. NF-κB was found to be activated in breast cancer cells that form tumorspheres efficiently. Moreover, both canonical and non-canonical NF-κB signaling is required for these cells to self-renew in vitro and to form xenograft tumors efficiently in vivo using limiting dilutions of cells. Consistent with this, canonical and non-canonical NF-κB signaling is activated in TICs isolated from breast cancer cell lines. Experimental results indicate that NF-κB promotes the function of TICs by stimulating epithelial-to-mesenchymal transition (EMT) and by upregulating the expression of the inflammatory cytokines IL-1β and IL-6. The results suggest the use of NF-κB inhibitors for clinical therapy of certain breast cancers. PMID:23474754

  10. Sirtuin 6 prevents matrix degradation through inhibition of the NF-κB pathway in intervertebral disc degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Liang [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Hu, Jia [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Weng, Yuxiong [Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Jia, Jie [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Zhang, Yukun, E-mail: zhangyukuncom@126.com [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China)

    2017-03-15

    Intervertebral disc degeneration (IDD) is marked by imbalanced metabolism of the extracellular matrix (ECM) in the nucleus pulposus (NP) of intervertebral discs. This study aimed to determine whether sirtuin 6 (SIRT6), a member of the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases, protects the NP from ECM degradation in IDD. Our study showed that expression of SIRT6 markedly decreased during IDD progression. Overexpression of wild-type SIRT6, but not a catalytically inactive mutant, prevented IL-1β-induced NP ECM degradation. SIRT6 depletion by RNA interference in NP cells caused ECM degradation. Moreover, SIRT6 physically interacted with nuclear factor-κB (NF-κB) catalytic subunit p65, transcriptional activity of which was significantly suppressed by SIRT6 overexpression. These results suggest that SIRT6 prevented NP ECM degradation in vitro via inhibiting NF-κB-dependent transcriptional activity and that this effect depended on its deacetylase activity. - Highlights: • SIRT6 expression is decreased in degenerative nucleus pulposus (NP) tissues. • SIRT6 overexpression lowers IL-1β-induced matrix degradation of NP. • SIRT6 inhibition induces matrix degradation of NP. • SIRT6 prevents matrix degradation of NP via the NF-κB signaling pathway.

  11. Sirtuin 6 prevents matrix degradation through inhibition of the NF-κB pathway in intervertebral disc degeneration

    International Nuclear Information System (INIS)

    Kang, Liang; Hu, Jia; Weng, Yuxiong; Jia, Jie; Zhang, Yukun

    2017-01-01

    Intervertebral disc degeneration (IDD) is marked by imbalanced metabolism of the extracellular matrix (ECM) in the nucleus pulposus (NP) of intervertebral discs. This study aimed to determine whether sirtuin 6 (SIRT6), a member of the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases, protects the NP from ECM degradation in IDD. Our study showed that expression of SIRT6 markedly decreased during IDD progression. Overexpression of wild-type SIRT6, but not a catalytically inactive mutant, prevented IL-1β-induced NP ECM degradation. SIRT6 depletion by RNA interference in NP cells caused ECM degradation. Moreover, SIRT6 physically interacted with nuclear factor-κB (NF-κB) catalytic subunit p65, transcriptional activity of which was significantly suppressed by SIRT6 overexpression. These results suggest that SIRT6 prevented NP ECM degradation in vitro via inhibiting NF-κB-dependent transcriptional activity and that this effect depended on its deacetylase activity. - Highlights: • SIRT6 expression is decreased in degenerative nucleus pulposus (NP) tissues. • SIRT6 overexpression lowers IL-1β-induced matrix degradation of NP. • SIRT6 inhibition induces matrix degradation of NP. • SIRT6 prevents matrix degradation of NP via the NF-κB signaling pathway.

  12. Overexpression of StNF-YB3.1 reduces photosynthetic capacity and tuber production, and promotes ABA-mediated stomatal closure in potato (Solanum tuberosum L.).

    Science.gov (United States)

    Xuanyuan, Guochao; Lu, Congming; Zhang, Ruofang; Jiang, Jiming

    2017-08-01

    Nuclear factor Y (NF-Y) is one of the most ubiquitous transcription factors (TFs), comprising NF-YA, NF-YB and NF-YC subunits, and has been identified and reported in various aspects of development for plants and animals. In this work, StNF-YB3.1, a putative potato NF-YB subunit encoding gene, was isolated from Solanum tuberosum by rapid amplification of cDNA ends (RACE). Overexpression of StNF-YB3.1 in potato (cv. Atlantic) resulted in accelerated onset of flowering, and significant increase in leaf chlorophyll content in field trials. However, transgenic potato plants overexpressing StNF-YB3.1 (OEYB3.1) showed significant decreases in photosynthetic rate and stomatal conductance both at tuber initiation and bulking stages. OEYB3.1 lines were associated with significantly fewer tuber numbers and yield reduction. Guard cell size and stomatal density were not changed in OEYB3.1 plants, whereas ABA-mediated stomatal closure was accelerated compared to that of wild type plants because of the up-regulation of genes for ABA signaling, such as StCPK10-like, StSnRK2.6/OST1-like, StSnRK2.7-like and StSLAC1-like. We speculate that the acceleration of stomatal closure was a possible reason for the significantly decreased stomatal conductance and photosynthetic rate. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. NF-κB Protects NKT Cells from Tumor Necrosis Factor Receptor 1-induced Death.

    Science.gov (United States)

    Kumar, Amrendra; Gordy, Laura E; Bezbradica, Jelena S; Stanic, Aleksandar K; Hill, Timothy M; Boothby, Mark R; Van Kaer, Luc; Joyce, Sebastian

    2017-11-15

    Semi-invariant natural killer T (NKT) cells are innate-like lymphocytes with immunoregulatory properties. NKT cell survival during development requires signal processing by activated RelA/NF-κB. Nonetheless, the upstream signal(s) integrated by NF-κB in developing NKT cells remains incompletely defined. We show that the introgression of Bcl-x L -coding Bcl2l1 transgene into NF-κB signalling-deficient IκBΔN transgenic mouse rescues NKT cell development and differentiation in this mouse model. We reasoned that NF-κB activation was protecting developing NKT cells from death signals emanating either from high affinity agonist recognition by the T cell receptor (TCR) or from a death receptor, such as tumor necrosis factor receptor 1 (TNFR1) or Fas. Surprisingly, the single and combined deficiency in PKC-θ or CARMA-1-the two signal transducers at the NKT TCR proximal signalling node-only partially recapitulated the NKT cell deficiency observed in IκBΔN tg mouse. Accordingly, introgression of the Bcl2l1 transgene into PKC-θ null mouse failed to rescue NKT cell development. Instead, TNFR1-deficiency, but not the Fas-deficiency, rescued NKT cell development in IκBΔN tg mice. Consistent with this finding, treatment of thymocytes with an antagonist of the inhibitor of κB kinase -which blocks downstream NF-κB activation- sensitized NKT cells to TNF-α-induced cell death in vitro. Hence, we conclude that signal integration by NF-κB protects developing NKT cells from death signals emanating from TNFR1, but not from the NKT TCR or Fas.

  14. RelAp43, a member of the NF-κB family involved in innate immune response against Lyssavirus infection.

    Science.gov (United States)

    Luco, Sophie; Delmas, Olivier; Vidalain, Pierre-Olivier; Tangy, Frédéric; Weil, Robert; Bourhy, Hervé

    2012-01-01

    NF-κB transcription factors are crucial for many cellular processes. NF-κB is activated by viral infections to induce expression of antiviral cytokines. Here, we identified a novel member of the human NF-κB family, denoted RelAp43, the nucleotide sequence of which contains several exons as well as an intron of the RelA gene. RelAp43 is expressed in all cell lines and tissues tested and exhibits all the properties of a NF-κB protein. Although its sequence does not include a transactivation domain, identifying it as a class I member of the NF-κB family, it is able to potentiate RelA-mediated transactivation and stabilize dimers comprising p50. Furthermore, RelAp43 stimulates the expression of HIAP1, IRF1, and IFN-β - three genes involved in cell immunity against viral infection. It is also targeted by the matrix protein of lyssaviruses, the agents of rabies, resulting in an inhibition of the NF-κB pathway. Taken together, our data provide the description of a novel functional member of the NF-κB family, which plays a key role in the induction of anti-viral innate immune response.

  15. RelAp43, a member of the NF-κB family involved in innate immune response against Lyssavirus infection.

    Directory of Open Access Journals (Sweden)

    Sophie Luco

    Full Text Available NF-κB transcription factors are crucial for many cellular processes. NF-κB is activated by viral infections to induce expression of antiviral cytokines. Here, we identified a novel member of the human NF-κB family, denoted RelAp43, the nucleotide sequence of which contains several exons as well as an intron of the RelA gene. RelAp43 is expressed in all cell lines and tissues tested and exhibits all the properties of a NF-κB protein. Although its sequence does not include a transactivation domain, identifying it as a class I member of the NF-κB family, it is able to potentiate RelA-mediated transactivation and stabilize dimers comprising p50. Furthermore, RelAp43 stimulates the expression of HIAP1, IRF1, and IFN-β - three genes involved in cell immunity against viral infection. It is also targeted by the matrix protein of lyssaviruses, the agents of rabies, resulting in an inhibition of the NF-κB pathway. Taken together, our data provide the description of a novel functional member of the NF-κB family, which plays a key role in the induction of anti-viral innate immune response.

  16. Bacterial effector binding to ribosomal protein s3 subverts NF-kappaB function.

    Directory of Open Access Journals (Sweden)

    Xiaofei Gao

    2009-12-01

    Full Text Available Enteric bacterial pathogens cause food borne disease, which constitutes an enormous economic and health burden. Enterohemorrhagic Escherichia coli (EHEC causes a severe bloody diarrhea following transmission to humans through various means, including contaminated beef and vegetable products, water, or through contact with animals. EHEC also causes a potentially fatal kidney disease (hemolytic uremic syndrome for which there is no effective treatment or prophylaxis. EHEC and other enteric pathogens (e.g., enteropathogenic E. coli (EPEC, Salmonella, Shigella, Yersinia utilize a type III secretion system (T3SS to inject virulence proteins (effectors into host cells. While it is known that T3SS effectors subvert host cell function to promote diarrheal disease and bacterial transmission, in many cases, the mechanisms by which these effectors bind to host proteins and disrupt the normal function of intestinal epithelial cells have not been completely characterized. In this study, we present evidence that the E. coli O157:H7 nleH1 and nleH2 genes encode T3SS effectors that bind to the human ribosomal protein S3 (RPS3, a subunit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB transcriptional complexes. NleH1 and NleH2 co-localized with RPS3 in the cytoplasm, but not in cell nuclei. The N-terminal region of both NleH1 and NleH2 was required for binding to the N-terminus of RPS3. NleH1 and NleH2 are autophosphorylated Ser/Thr protein kinases, but their binding to RPS3 is independent of kinase activity. NleH1, but not NleH2, reduced the nuclear abundance of RPS3 without altering the p50 or p65 NF-kappaB subunits or affecting the phosphorylation state or abundance of the inhibitory NF-kappaB chaperone IkappaBalpha NleH1 repressed the transcription of a RPS3/NF-kappaB-dependent reporter plasmid, but did not inhibit the transcription of RPS3-independent reporters. In contrast, NleH2 stimulated RPS3-dependent transcription, as well

  17. Spontaneous NF-κB activation by autocrine TNFα signaling: a computational analysis.

    Directory of Open Access Journals (Sweden)

    Jakub Pękalski

    Full Text Available NF-κB is a key transcription factor that regulates innate immune response. Its activity is tightly controlled by numerous feedback loops, including two negative loops mediated by NF-κB inducible inhibitors, IκBα and A20, which assure oscillatory responses, and by positive feedback loops arising due to the paracrine and autocrine regulation via TNFα, IL-1 and other cytokines. We study the NF-κB system of interlinked negative and positive feedback loops, combining bifurcation analysis of the deterministic approximation with stochastic numerical modeling. Positive feedback assures the existence of limit cycle oscillations in unstimulated wild-type cells and introduces bistability in A20-deficient cells. We demonstrated that cells of significant autocrine potential, i.e., cells characterized by high secretion of TNFα and its receptor TNFR1, may exhibit sustained cytoplasmic-nuclear NF-κB oscillations which start spontaneously due to stochastic fluctuations. In A20-deficient cells even a small TNFα expression rate qualitatively influences system kinetics, leading to long-lasting NF-κB activation in response to a short-pulsed TNFα stimulation. As a consequence, cells with impaired A20 expression or increased TNFα secretion rate are expected to have elevated NF-κB activity even in the absence of stimulation. This may lead to chronic inflammation and promote cancer due to the persistent activation of antiapoptotic genes induced by NF-κB. There is growing evidence that A20 mutations correlate with several types of lymphomas and elevated TNFα secretion is characteristic of many cancers. Interestingly, A20 loss or dysfunction also leaves the organism vulnerable to septic shock and massive apoptosis triggered by the uncontrolled TNFα secretion, which at high levels overcomes the antiapoptotic action of NF-κB. It is thus tempting to speculate that some cancers of deregulated NF-κB signaling may be prone to the pathogen-induced apoptosis.

  18. Comparison of Transcription Factor Binding Site Models

    KAUST Repository

    Bhuyan, Sharifulislam

    2012-05-01

    Modeling of transcription factor binding sites (TFBSs) and TFBS prediction on genomic sequences are important steps to elucidate transcription regulatory mechanism. Dependency of transcription regulation on a great number of factors such as chemical specificity, molecular structure, genomic and epigenetic characteristics, long distance interaction, makes this a challenging problem. Different experimental procedures generate evidence that DNA-binding domains of transcription factors show considerable DNA sequence specificity. Probabilistic modeling of TFBSs has been moderately successful in identifying patterns from a family of sequences. In this study, we compare performances of different probabilistic models and try to estimate their efficacy over experimental TFBSs data. We build a pipeline to calculate sensitivity and specificity from aligned TFBS sequences for several probabilistic models, such as Markov chains, hidden Markov models, Bayesian networks. Our work, containing relevant statistics and evaluation for the models, can help researchers to choose the most appropriate model for the problem at hand.

  19. Inhibition of Oncogenic Transcription Factor REL by the Natural Product Derivative Calafianin Monomer 101 Induces Proliferation Arrest and Apoptosis in Human B-Lymphoma Cell Lines.

    Science.gov (United States)

    Yeo, Alan T; Chennamadhavuni, Spandan; Whitty, Adrian; Porco, John A; Gilmore, Thomas D

    2015-04-23

    Increased activity of transcription factor NF-κB has been implicated in many B-cell lymphomas. We investigated effects of synthetic compound calafianin monomer (CM101) on biochemical and biological properties of NF-κB. In human 293 cells, CM101 selectively inhibited DNA binding by overexpressed NF-κB subunits REL (human c-Rel) and p65 as compared to NF-κB p50, and inhibition of REL and p65 DNA binding by CM101 required a conserved cysteine residue. CM101 also inhibited DNA binding by REL in human B-lymphoma cell lines, and the sensitivity of several B-lymphoma cell lines to CM101-induced proliferation arrest and apoptosis correlated with levels of cellular and nuclear REL. CM101 treatment induced both phosphorylation and decreased expression of anti-apoptotic protein Bcl-XL, a REL target gene product, in sensitive B-lymphoma cell lines. Ectopic expression of Bcl-XL protected SUDHL-2 B-lymphoma cells against CM101-induced apoptosis, and overexpression of a transforming mutant of REL decreased the sensitivity of BJAB B-lymphoma cells to CM101-induced apoptosis. Lipopolysaccharide-induced activation of NF-κB signaling upstream components occurred in RAW264.7 macrophages at CM101 concentrations that blocked NF-κB DNA binding. Direct inhibitors of REL may be useful for treating B-cell lymphomas in which REL is active, and may inhibit B-lymphoma cell growth at doses that do not affect some immune-related responses in normal cells.

  20. SLPI and inflammatory lung disease in females.

    LENUS (Irish Health Repository)

    McKiernan, Paul J

    2012-02-01

    During the course of certain inflammatory lung diseases, SLPI (secretory leucoprotease inhibitor) plays a number of important roles. As a serine antiprotease it functions to protect the airways from proteolytic damage due to neutrophil and other immune cell-derived serine proteases. With respect to infection it has known antimicrobial and anti-viral properties that are likely to contribute to host defence. Another of its properties is the ability to control inflammation within the lung where it can interfere with the transcriptional induction of pro-inflammatory gene expression induced by NF-kappaB (nuclear factor kappaB). Thus, factors that regulate the expression of SLPI in the airways can impact on disease severity and outcome. Gender represents once such idiosyncratic factor. In females with CF (cystic fibrosis), it is now thought that circulating oestrogen contributes, in part, to the observed gender gap whereby females have worse disease and poorer prognosis than males. Conversely, in asthma, sufferers who are females have more frequent exacerbations at times of low-circulating oestrogen. In the present paper, we discuss how SLPI participates in these events and speculate on whether regulatory mechanisms such as post-transcriptional modulation by miRNAs (microRNAs) are important in the control of SLPI expression in inflammatory lung disease.

  1. The MC160 Protein Expressed by the Dermatotropic Poxvirus Molluscum Contagiosum Virus Prevents Tumor Necrosis Factor Alpha-Induced NF-κB Activation via Inhibition of I Kappa Kinase Complex Formation

    Science.gov (United States)

    Nichols, Daniel Brian; Shisler, Joanna L.

    2006-01-01

    The pluripotent cytokine tumor necrosis factor alpha (TNF-α) binds to its cognate TNF receptor I (TNF-RI) to stimulate inflammation via activation of the NF-κB transcription factor. To prevent the detrimental effects of TNF-α in keratinocytes infected with the molluscum contagiosum virus (MCV), this poxvirus is expected to produce proteins that block at least one step of the TNF-RI signal transduction pathway. One such product, the MC160 protein, is predicted to interfere with this cellular response because of its homology to other proteins that regulate TNF-RI-mediated signaling. We report here that expression of MC160 molecules did significantly reduce TNF-α-mediated NF-κB activation in 293T cells, as measured by gene reporter and gel mobility shift assays. Since we observed that MC160 decreased other NF-κB activation pathways, namely those activated by receptor-interacting protein, TNF receptor-associated factor 2, NF-κB-inducing kinase, or MyD88, we hypothesized that the MC160 product interfered with I kappa kinase (IKK) activation, an event common to multiple signal transduction pathways. Indeed, MC160 protein expression was associated with a reduction in in vitro IKK kinase activity and IKK subunit phosphorylation. Further, IKK1-IKK2 interactions were not detected in MC160-expressing cells, under conditions demonstrated to induce IKK complex formation, but interactions between the MC160 protein and the major IKK subunits were undetectable. Surprisingly, MC160 expression correlated with a decrease in IKK1, but not IKK2 levels, suggesting a mechanism for MC160 disruption of IKK1-IKK2 interactions. MCV has probably retained its MC160 gene to inhibit NF-κB activation by interfering with signaling via multiple biological mediators. In the context of an MCV infection in vivo, MC160 protein expression may dampen the cellular production of proinflammatory molecules and enhance persistent infections in host keratinocytes. PMID:16378960

  2. Dynamic phosphorylation of RelA on Ser42 and Ser45 in response to TNFα stimulation regulates DNA binding and transcription.

    Science.gov (United States)

    Lanucara, Francesco; Lam, Connie; Mann, Jelena; Monie, Tom P; Colombo, Stefano A P; Holman, Stephen W; Boyd, James; Dange, Manohar C; Mann, Derek A; White, Michael R H; Eyers, Claire E

    2016-07-01

    The NF-κB signalling module controls transcription through a network of protein kinases such as the IKKs, as well as inhibitory proteins (IκBs) and transcription factors including RelA/p65. Phosphorylation of the NF-κB subunits is critical for dictating system dynamics. Using both non-targeted discovery and quantitative selected reaction monitoring-targeted proteomics, we show that the cytokine TNFα induces dynamic multisite phosphorylation of RelA at a number of previously unidentified residues. Putative roles for many of these phosphorylation sites on RelA were predicted by modelling of various crystal structures. Stoichiometry of phosphorylation determination of Ser45 and Ser42 revealed preferential early phosphorylation of Ser45 in response to TNFα. Quantitative analyses subsequently confirmed differential roles for pSer42 and pSer45 in promoter-specific DNA binding and a role for both of these phosphosites in regulating transcription from the IL-6 promoter. These temporal dynamics suggest that RelA-mediated transcription is likely to be controlled by functionally distinct NF-κB proteoforms carrying different combinations of modifications, rather than a simple 'one modification, one effect' system. © 2016 The Authors.

  3. Human xenospecific T suppressor cells inhibit T helper cell proliferation to porcine aortic endothelial cells, and NF-kappaB activity in porcine APC.

    Science.gov (United States)

    Ciubotariu, R; Li, J; Colovai, A I; Platt, J L; Cortesini, R; Suciu Foca Cortesini, N

    2001-05-01

    Human T suppressor cells (Ts), capable of preventing autologous T helper cells (Th) from reacting against xenogeneic pig endothelial cells and pig APC can be generated in vitro. Ts derive from a population of CD3(+)CD8(+)CD28(-) T lymphocytes and specifically recognize the MHC class I antigens of the APC used for in vitro immunization. To study the mechanism that underlies suppression, we investigated whether Ts inhibit the expression of costimulatory molecules in xenogeneic professional and semiprofessional APC. We found that Ts down-regulate Th-induced expression of CD86 in pig APC, and that this effect occurs at the level of transcription, as indicated by nuclear run-on and Northern blot assays. EMSA results revealed that inhibition of CD86 expression is mediated by inactivation of transcription factor NF-kappaB. Furthermore, transfection of pig APC with a vector expressing NF-kappaB p65 partially rescued Th-induced expression of the CD86 molecule. These results strongly support the concept that xenospecific Ts inhibit the APC function of xenogeneic cells by preventing activation of NF-kappaB.

  4. Expansion of myeloid-derived suppressor cells with aging in the bone marrow of mice through a NF-κB-dependent mechanism.

    Science.gov (United States)

    Flores, Rafael R; Clauson, Cheryl L; Cho, Joonseok; Lee, Byeong-Chel; McGowan, Sara J; Baker, Darren J; Niedernhofer, Laura J; Robbins, Paul D

    2017-06-01

    With aging, there is progressive loss of tissue homeostasis and functional reserve, leading to an impaired response to stress and an increased risk of morbidity and mortality. A key mediator of the cellular response to damage and stress is the transcription factor NF-κB. We demonstrated previously that NF-κB transcriptional activity is upregulated in tissues from both natural aged mice and in a mouse model of a human progeroid syndrome caused by defective repair of DNA damage (ERCC1-deficient mice). We also demonstrated that genetic reduction in the level of the NF-κB subunit p65(RelA) in the Ercc1 -/∆ progeroid mouse model of accelerated aging delayed the onset of age-related pathology including muscle wasting, osteoporosis, and intervertebral disk degeneration. Here, we report that the largest fraction of NF-κB -expressing cells in the bone marrow (BM) of aged (>2 year old) mice (C57BL/6-NF-κB EGFP reporter mice) are Gr-1 + CD11b + myeloid-derived suppressor cells (MDSCs). There was a significant increase in the overall percentage of MDSC present in the BM of aged animals compared with young, a trend also observed in the spleen. However, the function of these cells appears not to be compromised in aged mice. A similar increase of MDSC was observed in BM of progeroid Ercc1 -/∆ and BubR1 H/H mice. The increase in MDSC in Ercc1 -/∆ mice was abrogated by heterozygosity in the p65/RelA subunit of NF-κB. These results suggest that NF-κB activation with aging, at least in part, drives an increase in the percentage of MDSCs, a cell type able to suppress immune cell responses. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  5. Radiation-induced gene responses

    International Nuclear Information System (INIS)

    Woloschak, G.E.; Paunesku, T.; Shearin-Jones, P.; Oryhon, J.

    1996-01-01

    In the process of identifying genes that are differentially regulated in cells exposed to ultraviolet radiation (UV), we identified a transcript that was repressed following the exposure of cells to a combination of UV and salicylate, a known inhibitor of NF-kappaB. Sequencing this band determined that it has identify to lactate dehydrogenase, and Northern blots confirmed the initial expression pattern. Analysis of the sequence of the LDH 5' region established the presence of NF-kappaB, Sp1, and two Ap-2 elements; two partial AP- 1; one partial RE, and two halves of E-UV elements were also found. Electromobility shift assays were then performed for the AP-1, NF- kappaB, and E-UV elements. These experiments revealed that binding to NF-kappaB was induced by UV but repressed with salicylic acid; UV did not affect AP-1 binding, but salicylic acid inhibited it alone or following UV exposure; and E-UV binding was repressed by UV, and salicylic acid had little effect. Since the binding of no single element correlated with the expression pattern of LDH, it is likely that multiple elements govern UV/salicylate-mediated expression

  6. Peroxiredoxin 6 expression is inversely correlated with nuclear factor-κB activation during Clonorchis sinensis infestation.

    Science.gov (United States)

    Pak, Jhang Ho; Son, Woo Chan; Seo, Sang-Beom; Hong, Sung-Jong; Sohn, Woon-Mok; Na, Byoung-Kuk; Kim, Tong-Soo

    2016-10-01

    Clonorchis sinensis is a carcinogenic human liver fluke. Its infection promotes persistent oxidative stress and chronic inflammation environments in the bile duct and surrounding liver tissues owing to direct contact with worms and their excretory-secretory products (ESPs), provoking epithelial hyperplasia, periductal fibrosis, and cholangiocarcinogenesis. We examined the reciprocal regulation of two ESP-induced redox-active proteins, NF-κB and peroxiredoxin 6 (Prdx6), during C. sinensis infection. Prdx6 overexpression suppressed intracellular free-radical generation by inhibiting NADPH oxidase2 and inducible nitric oxide synthase activation in the ESP-treated cholangiocarcinoma cells, substantially attenuating NF-κB-mediated inflammation. NF-κB overexpression decreased Prdx6 transcription levels by binding to two κB sites within the promoter. This transcriptional repression was compensated for by other ESP-induced redox-active transcription factors, including erythroid 2-related factor 2 (Nrf2), hypoxia inducible factor 1α (HIF1α), and CCAAT/enhancer-binding protein β (C/EBPβ). Distribution of immunoreactive Prdx6 and NF-κB was distinct in the early stages of infection in mouse livers but shared concomitant localization in the later stages. The intensity and extent of their immunoreactive staining in infected mouse livers are proportional to lesion severity and infection duration. The constitutive elevations of Prdx6 and NF-κB during C. sinensis infection may be associated with more severe persistent hepatobiliary abnormalities mediated by clonorchiasis. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Dendrobium moniliforme Exerts Inhibitory Effects on Both Receptor Activator of Nuclear Factor Kappa-B Ligand-Mediated Osteoclast Differentiation in Vitro and Lipopolysaccharide-Induced Bone Erosion in Vivo.

    Science.gov (United States)

    Baek, Jong Min; Kim, Ju-Young; Ahn, Sung-Jun; Cheon, Yoon-Hee; Yang, Miyoung; Oh, Jaemin; Choi, Min Kyu

    2016-03-01

    Dendrobium moniliforme (DM) is a well-known plant-derived extract that is widely used in Oriental medicine. DM and its chemical constituents have been reported to have a variety of pharmacological effects, including anti-oxidative, anti-inflammatory, and anti-tumor activities; however, no reports discuss the beneficial effects of DM on bone diseases such as osteoporosis. Thus, we investigated the relationship between DM and osteoclasts, cells that function in bone resorption. We found that DM significantly reduced receptor activator of nuclear factor kappa-B ligand (RANKL)-induced tartrate-resistant acid phosphatase (TRAP)-positive osteoclast formation; DM directly induced the down-regulation of c-Fos and nuclear factor of activated T cells c1 (NFATc1) without affecting other RANKL-dependent transduction pathways. In the later stages of osteoclast maturation, DM negatively regulated the organization of filamentous actin (F-actin), resulting in impaired bone-resorbing activity by the mature osteoclasts. In addition, micro-computed tomography (μ-CT) analysis of the murine model revealed that DM had a beneficial effect on lipopolysaccharide (LPS)-mediated bone erosion. Histological analysis showed that DM attenuated the degradation of trabecular bone matrix and formation of TRAP-positive osteoclasts in bone tissues. These results suggest that DM is a potential candidate for the treatment of metabolic bone disorders such as osteoporosis.

  8. Protein-protein interactions in the regulation of WRKY transcription factors.

    Science.gov (United States)

    Chi, Yingjun; Yang, Yan; Zhou, Yuan; Zhou, Jie; Fan, Baofang; Yu, Jing-Quan; Chen, Zhixiang

    2013-03-01

    It has been almost 20 years since the first report of a WRKY transcription factor, SPF1, from sweet potato. Great progress has been made since then in establishing the diverse biological roles of WRKY transcription factors in plant growth, development, and responses to biotic and abiotic stress. Despite the functional diversity, almost all analyzed WRKY proteins recognize the TTGACC/T W-box sequences and, therefore, mechanisms other than mere recognition of the core W-box promoter elements are necessary to achieve the regulatory specificity of WRKY transcription factors. Research over the past several years has revealed that WRKY transcription factors physically interact with a wide range of proteins with roles in signaling, transcription, and chromatin remodeling. Studies of WRKY-interacting proteins have provided important insights into the regulation and mode of action of members of the important family of transcription factors. It has also emerged that the slightly varied WRKY domains and other protein motifs conserved within each of the seven WRKY subfamilies participate in protein-protein interactions and mediate complex functional interactions between WRKY proteins and between WRKY and other regulatory proteins in the modulation of important biological processes. In this review, we summarize studies of protein-protein interactions for WRKY transcription factors and discuss how the interacting partners contribute, at different levels, to the establishment of the complex regulatory and functional network of WRKY transcription factors.

  9. Low nuclear body formation and tax SUMOylation do not prevent NF-kappaB promoter activation

    Directory of Open Access Journals (Sweden)

    Bonnet Amandine

    2012-09-01

    Full Text Available Abstract Background The Tax protein encoded by Human T-lymphotropic virus type 1 (HTLV-1 is a powerful activator of the NF-κB pathway, a property critical for HTLV-1-induced immortalization of CD4+ T lymphocytes. Tax permanently stimulates this pathway at a cytoplasmic level by activating the IκB kinase (IKK complex and at a nuclear level by enhancing the binding of the NF-κB factor RelA to its cognate promoters and by forming nuclear bodies, believed to represent transcriptionally active structures. In previous studies, we reported that Tax ubiquitination and SUMOylation play a critical role in Tax localization and NF-κB activation. Indeed, analysis of lysine Tax mutants fused or not to ubiquitin or SUMO led us to propose a two-step model in which Tax ubiquitination first intervenes to activate IKK while Tax SUMOylation is subsequently required for promoter activation within Tax nuclear bodies. However, recent studies showing that ubiquitin or SUMO can modulate Tax activities in either the nucleus or the cytoplasm and that SUMOylated Tax can serve as substrate for ubiquitination suggested that Tax ubiquitination and SUMOylation may mediate redundant rather than successive functions. Results In this study, we analyzed the properties of a new Tax mutant that is properly ubiquitinated, but defective for both nuclear body formation and SUMOylation. We report that reducing Tax SUMOylation and nuclear body formation do not alter the ability of Tax to activate IKK, induce RelA nuclear translocation, and trigger gene expression from a NF-κB promoter. Importantly, potent NF-κB promoter activation by Tax despite low SUMOylation and nuclear body formation is also observed in T cells, including CD4+ primary T lymphocytes. Moreover, we show that Tax nuclear bodies are hardly observed in HTLV-1-infected T cells. Finally, we provide direct evidence that the degree of NF-κB activation by Tax correlates with the level of Tax ubiquitination, but not

  10. Low nuclear body formation and tax SUMOylation do not prevent NF-kappaB promoter activation.

    Science.gov (United States)

    Bonnet, Amandine; Randrianarison-Huetz, Voahangy; Nzounza, Patrycja; Nedelec, Martine; Chazal, Maxime; Waast, Laetitia; Pene, Sabrina; Bazarbachi, Ali; Mahieux, Renaud; Bénit, Laurence; Pique, Claudine

    2012-09-25

    The Tax protein encoded by Human T-lymphotropic virus type 1 (HTLV-1) is a powerful activator of the NF-κB pathway, a property critical for HTLV-1-induced immortalization of CD4⁺ T lymphocytes. Tax permanently stimulates this pathway at a cytoplasmic level by activating the IκB kinase (IKK) complex and at a nuclear level by enhancing the binding of the NF-κB factor RelA to its cognate promoters and by forming nuclear bodies, believed to represent transcriptionally active structures. In previous studies, we reported that Tax ubiquitination and SUMOylation play a critical role in Tax localization and NF-κB activation. Indeed, analysis of lysine Tax mutants fused or not to ubiquitin or SUMO led us to propose a two-step model in which Tax ubiquitination first intervenes to activate IKK while Tax SUMOylation is subsequently required for promoter activation within Tax nuclear bodies. However, recent studies showing that ubiquitin or SUMO can modulate Tax activities in either the nucleus or the cytoplasm and that SUMOylated Tax can serve as substrate for ubiquitination suggested that Tax ubiquitination and SUMOylation may mediate redundant rather than successive functions. In this study, we analyzed the properties of a new Tax mutant that is properly ubiquitinated, but defective for both nuclear body formation and SUMOylation. We report that reducing Tax SUMOylation and nuclear body formation do not alter the ability of Tax to activate IKK, induce RelA nuclear translocation, and trigger gene expression from a NF-κB promoter. Importantly, potent NF-κB promoter activation by Tax despite low SUMOylation and nuclear body formation is also observed in T cells, including CD4⁺ primary T lymphocytes. Moreover, we show that Tax nuclear bodies are hardly observed in HTLV-1-infected T cells. Finally, we provide direct evidence that the degree of NF-κB activation by Tax correlates with the level of Tax ubiquitination, but not SUMOylation. These data reveal that the

  11. Emerging Functions of Transcription Factors in Malaria Parasite

    Directory of Open Access Journals (Sweden)

    Renu Tuteja

    2011-01-01

    Full Text Available Transcription is a process by which the genetic information stored in DNA is converted into mRNA by enzymes known as RNA polymerase. Bacteria use only one RNA polymerase to transcribe all of its genes while eukaryotes contain three RNA polymerases to transcribe the variety of eukaryotic genes. RNA polymerase also requires other factors/proteins to produce the transcript. These factors generally termed as transcription factors (TFs are either associated directly with RNA polymerase or add in building the actual transcription apparatus. TFs are the most common tools that our cells use to control gene expression. Plasmodium falciparum is responsible for causing the most lethal form of malaria in humans. It shows most of its characteristics common to eukaryotic transcription but it is assumed that mechanisms of transcriptional control in P. falciparum somehow differ from those of other eukaryotes. In this article we describe the studies on the main TFs such as myb protein, high mobility group protein and ApiA2 family proteins from malaria parasite. These studies show that these TFs are slowly emerging to have defined roles in the regulation of gene expression in the parasite.

  12. NF1 Neuronal Genotype Phenotype Relationships

    Science.gov (United States)

    2017-06-01

    interesting results from the Drosophila functional assays, at present we have decided to focus our attention on selected NF1 patient missense mutations...complexity of NF1 disease phenotypes in different tissues, age and sex dependency of symptoms, impact of environmental factors and genetic heterogeneity...suggesting the role of modifier genes [12]. This work aims to shed light on this issue by studying the functional consequences of selected NF1

  13. Transcription Factor Functional Protein-Protein Interactions in Plant Defense Responses

    Directory of Open Access Journals (Sweden)

    Murilo S. Alves

    2014-03-01

    Full Text Available Responses to biotic stress in plants lead to dramatic reprogramming of gene expression, favoring stress responses at the expense of normal cellular functions. Transcription factors are master regulators of gene expression at the transcriptional level, and controlling the activity of these factors alters the transcriptome of the plant, leading to metabolic and phenotypic changes in response to stress. The functional analysis of interactions between transcription factors and other proteins is very important for elucidating the role of these transcriptional regulators in different signaling cascades. In this review, we present an overview of protein-protein interactions for the six major families of transcription factors involved in plant defense: basic leucine zipper containing domain proteins (bZIP, amino-acid sequence WRKYGQK (WRKY, myelocytomatosis related proteins (MYC, myeloblastosis related proteins (MYB, APETALA2/ ETHYLENE-RESPONSIVE ELEMENT BINDING FACTORS (AP2/EREBP and no apical meristem (NAM, Arabidopsis transcription activation factor (ATAF, and cup-shaped cotyledon (CUC (NAC. We describe the interaction partners of these transcription factors as molecular responses during pathogen attack and the key components of signal transduction pathways that take place during plant defense responses. These interactions determine the activation or repression of response pathways and are crucial to understanding the regulatory networks that modulate plant defense responses.

  14. NUR TRANSCRIPTION FACTORS IN STRESS AND ADDICTION

    Directory of Open Access Journals (Sweden)

    Danae eCampos-Melo

    2013-12-01

    Full Text Available The Nur transcription factors Nur77 (NGFI-B, NR4A1, Nurr1 (NR4A2 and Nor-1 (NR4A3 are a sub-family of orphan members of the nuclear receptor superfamily. These transcription factors are products of immediate early genes, whose expression is rapidly and transiently induced in the central nervous system by several types of stimuli. Nur factors are present throughout the hypothalamus-pituitary-adrenal axis where are prominently induced in response to stress. Drugs of abuse and stress also induce the expression of Nur factors in nuclei of the motivation/reward circuit of the brain, indicating their participation in the process of drug addiction and in non-hypothalamic responses to stress. Repeated use of addictive drugs and chronic stress induce long-lasting dysregulation of the brain motivation/reward circuit, due to reprogramming of gene expression and enduring alterations in neuronal function. Here, we review the data supporting that Nur transcription factors are key players in the molecular basis of the dysregulation of neuronal circuits involved in chronic stress and addiction.

  15. Prevalence of bortezomib-resistant constitutive NF-kappaB activity in mantle cell lymphoma

    Directory of Open Access Journals (Sweden)

    Kahl Brad S

    2008-05-01

    Full Text Available Abstract Background The proteasome inhibitor bortezomib can inhibit activation of the transcription factor NF-κB, a mechanism implicated in its anti-neoplastic effects observed in mantle cell lymphoma (MCL. However, NF-κB can be activated through many distinct mechanisms, including proteasome independent pathways. While MCL cells have been shown to harbor constitutive NF-κB activity, what fraction of this activity in primary MCL samples is sensitive or resistant to inhibition by bortezomib remains unclear. Results Proteasome activity in the EBV-negative MCL cell lines Jeko-1 and Rec-1 is inhibited by greater than 80% after exposure to 20 nM bortezomib for 4 hours. This treatment decreased NF-κB activity in Jeko-1 cells, but failed to do so in Rec-1 cells when assessed by electrophoretic mobility shift assay (EMSA. Concurrently, Rec-1 cells were more resistant to the cytotoxic effects of bortezomib than Jeko-1 cells. Consistent with a proteasome inhibitor resistant pathway of activation described in mouse B-lymphoma cells (WEHI231 and a breast carcinoma cell line (MDA-MB-468, the bortezomib-resistant NF-κB activity in Rec-1 cells is inhibited by calcium chelators, calmodulin inhibitors, and perillyl alcohol, a monoterpene capable of blocking L-type calcium channels. Importantly, the combination of perillyl alcohol and bortezomib is synergistic in eliciting Rec-1 cell cytotoxicity. The relevance of these results is illuminated by the additional finding that a considerable fraction of primary MCL samples (8 out of 10 displayed bortezomib-resistant constitutive NF-κB activity. Conclusion Our findings show that bortezomib-resistant NF-κB activity is frequently observed in MCL samples and suggest that this activity may be relevant to MCL biology as well as serve as a potential therapeutic target.

  16. Activation of NF-κB in basolateral amygdala is required for memory reconsolidation in auditory fear conditioning.

    Directory of Open Access Journals (Sweden)

    Jijian Si

    Full Text Available Posttraumatic stress disorder (PTSD is characterized by acute and chronic changes in the stress response, manifested as conditioned fear memory. Previously formed memories that are susceptible to disruption immediately after retrieval undergo a protein synthesis-dependent process to become persistent, termed reconsolidation, a process that is regulated by many distinct molecular mechanisms that control gene expression. Increasing evidence supports the participation of the transcription factor NF-κB in the different phases of memory. Here, we demonstrate that inhibition of NF-κB in the basolateral amygdala (BLA, but not central nucleus of the amygdala, after memory reactivation impairs the retention of amygdala-dependent auditory fear conditioning (AFC. We used two independent pharmacological strategies to disrupt the reconsolidation of AFC. Bilateral intra-BLA infusion of sulfasalazine, an inhibitor of IκB kinase that activates NF-κB, and bilateral intra-BLA infusion of SN50, a direct inhibitor of the NF-κB DNA-binding complex, immediately after retrieval disrupted the reconsolidation of AFC. We also found that systemic pretreatment with sodium butyrate, a histone deacetylase inhibitor that enhances histone acetylation, in the amygdala rescued the disruption of reconsolidation induced by NF-κB inhibition in the BLA. These findings indicate that NF-κB activity in the BLA is required for memory reconsolidation in AFC, suggesting that NF-κB might be a potential pharmacotherapy target for posttraumatic stress disorder.

  17. Cdc25A promotes cell survival by stimulating NF-κB activity through IκB-α phosphorylation and destabilization

    International Nuclear Information System (INIS)

    Hong, Hey-Young; Choi, Jiyeon; Cho, Young-Wook; Kim, Byung-Chul

    2012-01-01

    Highlights: ► We examine the antiapoptotic mechanisms of Cdc25A. ► Smad7 decreases the phosphorylation of IκB-alpha at Ser-32. ► Smad7 positively regulates NF-κB activity through IκB-alpha ubiquitination. -- Abstract: Cell division cycle 25A (Cdc25A), a dual specificity protein phosphatase, exhibits anti-apoptotic activity, but the underlying molecular mechanisms are poorly characterized. Here we report that Cdc25A inhibits cisplatin-induced apoptotic cell death by stimulating nuclear factor-kappa B (NF-κB) activity. In HEK-293 cells, Cdc25A decreased protein level of inhibitor subunit kappa B alpha (Iκ-Bα) in association with increased serine 32-phosphorylation, followed by stimulation of transcriptional activity of NF-κB. Inhibition of NF-κB activity by chemical inhibitor or overexpression of Iκ-Bα in Cdc25A-elevated cancer cells resistant to cisplatin improved their sensitivity to cisplatin-induced apoptosis. Our data show for the first time that Cdc25A has an important physiological role in NF-κB activity regulation and it may be an important survival mechanism of cancer cells.

  18. NF-κB RelA renders tumor-associated macrophages resistant to and capable of directly suppressing CD8+ T cells for tumor promotion.

    Science.gov (United States)

    Li, Liwen; Han, Lei; Sun, Fan; Zhou, Jingjiao; Ohaegbulam, Kim C; Tang, Xudong; Zang, Xingxing; Steinbrecher, Kris A; Qu, Zhaoxia; Xiao, Gutian

    2018-01-01

    Activation of the inflammatory transcription factor NF-κB in tumor-associated macrophages (TAMs) is assumed to contribute to tumor promotion. However, whether and how NF-κB drives the antitumor macrophages to become pro-tumorigenic have not been determined in any cancer type yet. Similarly, how TAMs repress CD8 + cytotoxic T lymphocytes (CTLs) remains largely unknown, although their importance in regulatory T (Treg) cell regulation and tumor promotion has been well appreciated. Here, using an endogenous lung cancer model we uncover a direct crosstalk between TAMs and CTLs. TAMs suppress CTLs through the T-cell inhibitory molecule B7x (B7-H4/B7S1) in a cell-cell contact manner, whereas CTLs kill TAMs in a tumor antigen-specific manner. Remarkably, TAMs secrete the known T-cell suppressive cytokine interleukin-10 (IL-10) to activate, but not to repress, CTLs. Notably, one major role of cell-intrinsic NF-κB RelA is to drive TAMs to suppress CTLs for tumor promotion. It induces B7x expression in TAMs directly, and restricts IL-10 expression indirectly by repressing expression of the NF-κB cofactor Bcl3 and subsequent Bcl3/NF-κB1-mediated transcription of IL-10. It also renders TAMs resistant to CTLs by up-regulating anti-apoptotic genes. These studies help understand how immunity is shaped in lung tumorigenesis, and suggest a RelA-targeted immunotherapy for this deadliest cancer.

  19. Salicortin inhibits osteoclast differentiation and bone resorption by down-regulating JNK and NF-κB/NFATc1 signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Nie, Shaobo [Department of Orthopaedics, PLA General Hospital, Beijing 100853 (China); Xu, Jiawei [Department of Orthopaedics, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Zhang, Chenghua [Department of Orthopaedics, Changle County Hospital of Traditional Chinese Medicine, Weifang 262400 (China); Xu, Chen [Department of Orthopaedics, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Liu, Ming, E-mail: ming_li4717@sina.com [Department of Orthopaedics, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Yu, Degang, E-mail: ydg163@126.com [Department of Orthopaedics, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China)

    2016-01-29

    Receptor activator of nuclear factor (NF)-κB ligand (RANKL)-activated signaling is essential for osteoclast differentiation, activation, and survival. Salicortin is a phenolic glycoside that has been isolated from many plants such as Populus and Salix species, and has been shown to have anti-amnesic and anti-adipogenic effects. In this study, we investigated the effect of salicortin on RANKL-induced osteoclasts formation, bone resorption, and activation of osteoclast-related signaling pathways. Salicortin suppressed RANKL-induced osteoclastogenesis in bone marrow macrophage cultures in a dose-dependent manner, and inhibited osteoclastic bone resorption activity without any cytotoxicity. Salicortin inhibited RANKL-induced c-Jun N-terminal kinase and NF-κB activation, concomitant with retarded IκBα phosphorylation and inhibition of p65 nuclear translocation, leading to impaired transcription of nuclear factor of activated T cells c1 (NFATc1) and expression of osteoclastic-specific genes. Taken together, our findings demonstrate that salicortin inhibits NF-κB and NFATc1 activation, leading to attenuation of osteoclastogenesis and bone resorption. Thus, salicortin may be of interest in developments of treatment for osteoclast related diseases. - Highlights: • Salicortin suppresses osteoclastogenesis in vitro. • Salicortin impairs the JNK and NF-κB/NFATc1 signaling pathway. • Salicortin may be of interest in developments of osteoporosis treatment.

  20. Salicortin inhibits osteoclast differentiation and bone resorption by down-regulating JNK and NF-κB/NFATc1 signaling pathways

    International Nuclear Information System (INIS)

    Nie, Shaobo; Xu, Jiawei; Zhang, Chenghua; Xu, Chen; Liu, Ming; Yu, Degang

    2016-01-01

    Receptor activator of nuclear factor (NF)-κB ligand (RANKL)-activated signaling is essential for osteoclast differentiation, activation, and survival. Salicortin is a phenolic glycoside that has been isolated from many plants such as Populus and Salix species, and has been shown to have anti-amnesic and anti-adipogenic effects. In this study, we investigated the effect of salicortin on RANKL-induced osteoclasts formation, bone resorption, and activation of osteoclast-related signaling pathways. Salicortin suppressed RANKL-induced osteoclastogenesis in bone marrow macrophage cultures in a dose-dependent manner, and inhibited osteoclastic bone resorption activity without any cytotoxicity. Salicortin inhibited RANKL-induced c-Jun N-terminal kinase and NF-κB activation, concomitant with retarded IκBα phosphorylation and inhibition of p65 nuclear translocation, leading to impaired transcription of nuclear factor of activated T cells c1 (NFATc1) and expression of osteoclastic-specific genes. Taken together, our findings demonstrate that salicortin inhibits NF-κB and NFATc1 activation, leading to attenuation of osteoclastogenesis and bone resorption. Thus, salicortin may be of interest in developments of treatment for osteoclast related diseases. - Highlights: • Salicortin suppresses osteoclastogenesis in vitro. • Salicortin impairs the JNK and NF-κB/NFATc1 signaling pathway. • Salicortin may be of interest in developments of osteoporosis treatment.

  1. Nf2-Yap signaling controls the expansion of DRG progenitors and glia during DRG development.

    Science.gov (United States)

    Serinagaoglu, Yelda; Paré, Joshua; Giovannini, Marco; Cao, Xinwei

    2015-02-01

    Molecular mechanisms governing the maintenance and proliferation of dorsal root ganglia (DRG) progenitors are largely unknown. Here we reveal that the Hippo pathway regulates the expansion of DRG progenitors and glia during mammalian DRG development. The key effectors of this pathway, transcriptional coactivators Yap and Taz, are expressed in DRG progenitors and glia during DRG development but are at least partially inhibited from activating transcription. Aberrant YAP activation leads to overexpansion of DRG progenitor and glial populations. We further show that the Neurofibromatosis 2 (Nf2) tumor suppressor inhibits Yap during DRG development. Loss of Nf2 leads to similar phenotypes as does YAP hyperactivation, and deleting Yap suppresses these phenotypes. Our study demonstrates that Nf2-Yap signaling plays important roles in controlling the expansion of DRG progenitors and glia during DRG development. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Spironolactone induces apoptosis and inhibits NF-kappaB independent of the mineralocorticoid receptor

    DEFF Research Database (Denmark)

    Sønder, Søren Ulrik Salling; Woetmann, Anders; Odum, Niels

    2006-01-01

    mononuclear cells (MNC). To elucidate the mechanism behind SPIR's apoptotic effect, we investigated the relation between apoptosis and cytokine suppression for SPIR along with the apoptosis-inducing and antiinflammatory drug sulfasalazine (SFZ). Using human MNC, we found that SPIR and SFZ, at concentrations...... 10 and 1000 muM, respectively, significantly increased both apoptosis and cell death. Production of inflammatory cytokines was significantly reduced by 3 to 30 muM SPIR and by 300 to 1000 muM SFZ. We also found that 0.4 muM SPIR and 300 muM SFZ significantly reduced the activity of NF......-kappaB, a transcription factor involved in both apoptosis and immunoinflammation. ALDO, the MR antagonist, eplerenone, and the SPIR metabolite, 7alpha-thiomethyl-spironolactone, slightly reduced NF-kappaB activity, but they did not interfere with SPIR's effect, showing that MR binding is not involved in SPIR...

  3. A novel electrochemical approach for nuclear factor kappa B detection based on triplex DNA and gold nanoparticles

    International Nuclear Information System (INIS)

    Shen Min; Yang Mei; Li Hao; Liang Zhiqiang; Li Genxi

    2012-01-01

    Highlights: ► A simple, selective, and sensitive electrochemical NF-κB sensor was presented. ► NF-κB was precisely qualified by chronocoulometry with a detection limit of 0.13 nM. ► NF-κB was also successfully detected in contaminated samples by our approach. - Abstract: The transcription factor nuclear factor kappa B (NF-κB) is always a standard for inducible transcription factors, while nearly all NF-κB studies require the measurement of the level of activated NF-κB in cells. Herein we report a novel electrochemical approach for accurate detection of NF-κB with the help of triplex DNA and gold nanoparticles (AuNPs). Firstly, double-stranded DNA (dsDNA) molecules are self-assembled on the surface of a gold electrode. Then, AuNPs are functionalized with triplex-forming oligonucleotide (TFO). Since TFO may act with the dsDNA to form triplex DNA, the TFO functionalized on the AuNPs surfaces will bind with the dsDNA immobilized on the electrode surface, bringing large amounts of electrochemical compounds [Ru(NH 3 ) 6 ] 3+ close to the electrode to generate an intense electrochemical signal. However, in the presence of NF-κB, the protein will capture and bind with the dsDNA to replace TFO–AuNPs, resulting in significant decrease of electrochemical signal of [Ru(NH 3 ) 6 ] 3+ . By using this “on-off” strategy, NF-κB has been quantified in the range from 0.4 to 12.0 nM, with a detection limit of 0.13 nM. This approach has also been successfully used to detect NF-κB in contaminated samples with high specificity.

  4. Withaferin A disrupts ubiquitin-based NEMO reorganization induced by canonical NF-κB signaling

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Shawn S. [McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, 6159 Wisconsin Institute for Medical Research, 1111 Highland Avenue, Madison, WI 53705 (United States); Medical Scientist Training Program, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705 (United States); Cellular and Molecular Biology Program, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705 (United States); Oberley, Christopher [McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, 6159 Wisconsin Institute for Medical Research, 1111 Highland Avenue, Madison, WI 53705 (United States); Hooper, Christopher P. [McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, 6159 Wisconsin Institute for Medical Research, 1111 Highland Avenue, Madison, WI 53705 (United States); Cellular and Molecular Biology Program, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705 (United States); Grindle, Kreg [Department of Medicine, Division of Hematology and Oncology, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705 (United States); Wuerzberger-Davis, Shelly [McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, 6159 Wisconsin Institute for Medical Research, 1111 Highland Avenue, Madison, WI 53705 (United States); Wolff, Jared [Department of Medicine, Division of Hematology and Oncology, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705 (United States); and others

    2015-02-01

    The NF-κB family of transcription factors regulates numerous cellular processes, including cell proliferation and survival responses. The constitutive activation of NF-κB has also emerged as an important oncogenic driver in many malignancies, such as activated B-cell like diffuse large B cell lymphoma, among others. In this study, we investigated the impact and mechanisms of action of Withaferin A, a naturally produced steroidal lactone, against both signal-inducible as well as constitutive NF-κB activities. We found that Withaferin A is a robust inhibitor of canonical and constitutive NF-κB activities, leading to apoptosis of certain lymphoma lines. In the canonical pathway induced by TNF, Withaferin A did not disrupt RIP1 polyubiquitination or NEMO–IKKβ interaction and was a poor direct IKKβ inhibitor, but prevented the formation of TNF-induced NEMO foci which colocalized with TNF ligand. While GFP-NEMO efficiently formed TNF-induced foci, a GFP-NEMO{sup Y308S} mutant that is defective in binding to polyubiquitin chains did not form foci. Our study reveals that Withaferin A is a novel type of IKK inhibitor which acts by disrupting NEMO reorganization into ubiquitin-based signaling structures in vivo. - Highlights: • Withaferin A, a NF-κB inhibitor, disrupts signaling induced NEMO localization, a novel point of inhibition. • NEMO can be localized to distinct signaling foci after treatment with TNF. • ABC-type DLCBL cells can be sensitized to apoptosis after treatment with Withaferin A.

  5. Targeting NF-kB signaling with polymeric hybrid micelles that co-deliver siRNA and dexamethasone for arthritis therapy.

    Science.gov (United States)

    Wang, Qin; Jiang, Hao; Li, Yan; Chen, Wenfei; Li, Hanmei; Peng, Ke; Zhang, Zhirong; Sun, Xun

    2017-04-01

    The transcription factor NF-kB plays a pivotal role in the pathogenesis of rheumatoid arthritis. Here we attempt to slow arthritis progression by co-delivering the glucocorticoid dexamethasone (Dex) and small-interfering RNA targeting NF-kB p65 using our previously developed polymeric hybrid micelle system. These micelles contain two similar amphiphilic copolymers: polycaprolactone-polyethylenimine (PCL-PEI) and polycaprolactone-polyethyleneglycol (PCL-PEG). The hybrid micelles loaded with Dex and siRNA effectively inhibited NF-kB signaling in murine macrophages more efficiently than micelles containing either Dex or siRNA on their own. In addition, the co-delivery system was able to switch macrophages from the M1 to M2 state. Injecting hybrid micelles containing Dex and siRNA into mice with collagen-induced arthritis led the therapeutic agents to accumulate in inflamed joints and reduce inflammation, without damaging renal or liver function. Thus, blocking NF-kB activation in inflammatory tissue using micelle-based co-delivery may provide a new approach for treating inflammatory disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Kaempferol modulates pro-inflammatory NF-κB activation by suppressing advanced glycation endproducts-induced NADPH oxidase

    Science.gov (United States)

    Kim, Ji Min; Lee, Eun Kyeong; Kim, Dae Hyun; Yu, Byung Pal

    2010-01-01

    Advanced glycation endproducts (AGE) are oxidative products formed from the reaction between carbohydrates and a free amino group of proteins that are provoked by reactive species (RS). It is also known that AGE enhance the generation of RS and that the binding of AGE to a specific AGE receptor (RAGE) induces the activation of the redox-sensitive, pro-inflammatory transcription factor, nuclear factor-kappa B (NF-ĸB). In this current study, we investigated the anti-oxidative effects of short-term kaempferol supplementation on the age-related formation of AGE and the binding activity of RAGE in aged rat kidney. We further investigated the suppressive action of kaempferol against AGE's ability to stimulate activation of pro-inflammatory NF-ĸB and its molecular mechanisms. For this study, we utilized young (6 months old), old (24 months old), and kaempferol-fed (2 and 4 mg/kg/day for 10 days) old rats. In addition, for the molecular work, the rat endothelial cell line, YPEN-1 was used. The results show that AGE and RAGE were increased during aging and that these increases were blunted by kaempferol. In addition, dietary kaempferol reduced age-related increases in NF-κB activity and NF-ĸB-dependant pro-inflammatory gene activity. The most significant new finding from this study is that kaempferol supplementation prevented age-related NF-κB activation by suppressing AGE-induced nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase). Taken together, our results demonstrated that dietary kaempferol exerts its anti-oxidative and anti-inflammatory actions by modulating the age-related NF-κB signaling cascade and its pro-inflammatory genes by suppressing AGE-induced NADPH oxidase activation. Based on these data, dietary kaempferol is proposed as a possible anti-AGE agent that may have the potential for use in anti-inflammation therapies. PMID:20431987

  7. A deeper look into transcription regulatory code by preferred pair distance templates for transcription factor binding sites

    KAUST Repository

    Kulakovskiy, Ivan V.; Belostotsky, A. A.; Kasianov, Artem S.; Esipova, Natalia G.; Medvedeva, Yulia; Eliseeva, Irina A.; Makeev, Vsevolod J.

    2011-01-01

    Motivation: Modern experimental methods provide substantial information on protein-DNA recognition. Studying arrangements of transcription factor binding sites (TFBSs) of interacting transcription factors (TFs) advances understanding

  8. PUMA and NF-kB Are Cell Signaling Predictors of Reovirus Oncolysis of Breast Cancer.

    Science.gov (United States)

    Thirukkumaran, Chandini; Shi, Zhong-Qiao; Thirukkumaran, Ponnampalam; Luider, Joanne; Kopciuk, Karen; Spurrell, Jason; Elzinga, Kate; Morris, Don

    2017-01-01

    Reovirus is a ubiquitous RNA virus that exploits aberrant signaling pathways for its replication. The oncolytic potential of reovirus against numerous cancers under pre-clinical/clinical conditions has been documented by us and others. Despite its proven clinical activity, the underlying mechanisms of reovirus oncolysis is still not well elucidated. If reovirus therapy is to be optimized for cancer, including breast cancer patients, it is imperative to understand the mechanisms of reovirus oncolysis, especially in treatment of resistant tumour. In the present study global gene expression profiling was utilized as a preliminary roadmap to tease-out pivotal molecules involved in reovirus induced apoptosis in breast cancer. Reovirus treated HTB133 and MCF7 breast cancer cells revealed transcriptional alteration of a defined subset of apoptotic genes and members of the nuclear factor-kappa B (NF-kB) family and p53 upregulated modulator of apoptosis (PUMA) were prominent. Since NF-kB can paradoxically suppress or promote apoptosis in cancer, the significance of NF-kB in reovirus oncolysis of breast cancer was investigated. Real time PCR analysis indicated a 2.9-4.3 fold increase in NF-kB p65 message levels following reovirus infection of MCF7 and HTB133, respectively. Nuclear translocation of NF-kB p65 protein was also dramatically augmented post reovirus treatment and correlated with enhanced DNA binding. Pharmacologic inhibition of NF-kB lead to oncolytic protection and significant down regulation of PUMA message levels. PUMA down regulation using siRNA suppressed reovirus oncolysis via significantly repressed apoptosis in p53 mutant HTB133 cells. This study demonstrates for the first time that a prominent pathway of reovirus oncolysis of breast cancer is mediated through NF-kB and that PUMA upregulation is dependent on NF-kB activation. These findings represent potential therapeutic indicators of reovirus treatment in future clinical trials.

  9. Factor requirements for transcription in the Archaeon Sulfolobus shibatae.

    Science.gov (United States)

    Qureshi, S A; Bell, S D; Jackson, S P

    1997-05-15

    Archaea (archaebacteria) constitute a domain of life that is distinct from Bacteria (eubacteria) and Eucarya (eukaryotes). Although archaeal cells share many morphological features with eubacteria, their transcriptional apparatus is more akin to eukaryotic RNA polymerases I, II and III than it is to eubacterial transcription systems. Thus, in addition to possessing a 10 subunit RNA polymerase and a homologue of the TATA-binding protein (TBP), Archaea possess a polypeptide termed TFB that is homologous to eukaryotic TFIIB. Here, we investigate the factor requirements for transcription of several promoters of the archaeon Sulfolobus shibatae and its associated virus SSV. Through in vitro transcription and immunodepletion, we demonstrate that S. shibatae TBP, TFB and RNA polymerase are not complexed tightly with one another and that each is required for efficient transcription of all promoters tested. Furthermore, full transcription is restored by supplementing respective depleted extracts with recombinant TBP or TFB, indicating that TBP-associated factors or TFB-associated factors are not required. Indeed, gel-filtration suggests that Sulfolobus TBP and TFB are not associated stably with other proteins. Finally, all promoters analysed are transcribed accurately and efficiently in an in vitro system comprising recombinant TBP and TFB, together with essentially homogeneous preparation of RNA polymerase. Transcription in Archaea is therefore fundamentally homologous to that in eukaryotes, although factor requirements appear to be much less complex.

  10. Transcription factor-based biosensor

    Science.gov (United States)

    Dietrich, Jeffrey A; Keasling, Jay D

    2013-10-08

    The present invention provides for a system comprising a BmoR transcription factor, a .sigma..sup.54-RNA polymerase, and a pBMO promoter operatively linked to a reporter gene, wherein the pBMO promoter is capable of expression of the reporter gene with an activated form of the BmoR and the .sigma..sup.54-RNA polymerase.

  11. Detecting Differential Transcription Factor Activity from ATAC-Seq Data

    Directory of Open Access Journals (Sweden)

    Ignacio J. Tripodi

    2018-05-01

    Full Text Available Transcription factors are managers of the cellular factory, and key components to many diseases. Many non-coding single nucleotide polymorphisms affect transcription factors, either by directly altering the protein or its functional activity at individual binding sites. Here we first briefly summarize high-throughput approaches to studying transcription factor activity. We then demonstrate, using published chromatin accessibility data (specifically ATAC-seq, that the genome-wide profile of TF recognition motifs relative to regions of open chromatin can determine the key transcription factor altered by a perturbation. Our method of determining which TFs are altered by a perturbation is simple, is quick to implement, and can be used when biological samples are limited. In the future, we envision that this method could be applied to determine which TFs show altered activity in response to a wide variety of drugs and diseases.

  12. Curcumin Modulates the Radiosensitivity of Colorectal Cancer Cells by Suppressing Constitutive and Inducible NF-κB Activity

    International Nuclear Information System (INIS)

    Sandur, Santosh K.; Deorukhkar, Amit; Pandey, Manoj K.; Pabon, Ana Maria B.S.; Shentu, Shujun; Guha, Sushovan; Aggarwal, Bharat B.; Krishnan, Sunil

    2009-01-01

    Purpose: Radiation therapy is an integral part of the preoperative treatment of rectal cancers. However, only a minority of patients achieve a complete pathologic response to therapy because of resistance of these tumors to radiation therapy. This resistance may be mediated by constitutively active pro-survival signaling pathways or by inducible/acquired mechanisms in response to radiation therapy. Simultaneous inhibition of these pathways can sensitize these tumors to radiation therapy. Methods and Materials: Human colorectal cancer cells were exposed to clinically relevant doses of gamma rays, and the mechanism of their radioresistance was investigated. We characterized the transcription factor nuclear factor-κB (NF-κB) activation as a mechanism of inducible radioresistance in colorectal cancer and used curcumin, the active ingredient in the yellow spice turmeric, to overcome this resistance. Results: Curcumin inhibited the proliferation and the post-irradiation clonogenic survival of multiple colorectal cancer cell lines. Radiation stimulated NF-κB activity in a dose- and time-dependent manner, whereas curcumin suppressed this radiation-induced NF-κB activation via inhibition of radiation-induced phosphorylation and degradation of inhibitor of κB alpha, inhibition of inhibitor of κB kinase activity, and inhibition of Akt phosphorylation. Curcumin also suppressed NF-κB-regulated gene products (Bcl-2, Bcl-x L , inhibitor of apoptosis protein-2, cyclooxygenase-2, and cyclin D1). Conclusions: Our results suggest that transient inducible NF-κB activation provides a prosurvival response to radiation that may account for development of radioresistance. Curcumin blocks this signaling pathway and potentiates the antitumor effects of radiation therapy.

  13. Functional Profiling of Transcription Factor Genes in Neurospora crassa

    Directory of Open Access Journals (Sweden)

    Alexander J. Carrillo

    2017-09-01

    Full Text Available Regulation of gene expression by DNA-binding transcription factors is essential for proper control of growth and development in all organisms. In this study, we annotate and characterize growth and developmental phenotypes for transcription factor genes in the model filamentous fungus Neurospora crassa. We identified 312 transcription factor genes, corresponding to 3.2% of the protein coding genes in the genome. The largest class was the fungal-specific Zn2Cys6 (C6 binuclear cluster, with 135 members, followed by the highly conserved C2H2 zinc finger group, with 61 genes. Viable knockout mutants were produced for 273 genes, and complete growth and developmental phenotypic data are available for 242 strains, with 64% possessing at least one defect. The most prominent defect observed was in growth of basal hyphae (43% of mutants analyzed, followed by asexual sporulation (38%, and the various stages of sexual development (19%. Two growth or developmental defects were observed for 21% of the mutants, while 8% were defective in all three major phenotypes tested. Analysis of available mRNA expression data for a time course of sexual development revealed mutants with sexual phenotypes that correlate with transcription factor transcript abundance in wild type. Inspection of this data also implicated cryptic roles in sexual development for several cotranscribed transcription factor genes that do not produce a phenotype when mutated.

  14. miR-339-5p inhibits alcohol-induced brain inflammation through regulating NF-κB pathway

    International Nuclear Information System (INIS)

    Zhang, Yu; Wei, Guangkuan; Di, Zhiyong; Zhao, Qingjie

    2014-01-01

    Graphical abstract: - Highlights: • Alcohol upregulates miR-339-5p expression. • miR-339-5p inhibits the NF-kB pathway. • miR-339-5p interacts with and blocks activity of IKK-beat and IKK-epsilon. • miR-339-5p modulates IL-1β, IL-6 and TNF-α. - Abstract: Alcohol-induced neuroinflammation is mediated by the innate immunesystem. Pro-inflammatory responses to alcohol are modulated by miRNAs. The miRNA miR-339-5p has previously been found to be upregulated in alcohol-induced neuroinflammation. However, little has been elucidated on the regulatory functions of this miRNA in alcohol-induced neuroinflammation. We investigated the function of miR-339-5p in alcohol exposed brain tissue and isolated microglial cells using ex vivo and in vitro techniques. Our results show that alcohol induces transcription of miR 339-5p, IL-6, IL-1β and TNF-α in mouse brain tissue and isolated microglial cells by activating NF-κB. Alcohol activation of NF-κB allows for nuclear translocation of the NF-κB subunit p65 and expression of pro-inflammatory mediators. miR-339-5p inhibited expression of these pro-inflammatory factors through the NF-κB pathway by abolishing IKK-β and IKK-ε activity

  15. miR-339-5p inhibits alcohol-induced brain inflammation through regulating NF-κB pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Neurology, The First Affiliated School of Harbin Medical University, Harbin 150001 (China); Wei, Guangkuan [Department of Neurology, Heilongjiang Provincial Hospital, Harbin 150036 (China); Di, Zhiyong [Department of Laboratory, Heilongjiang Provincial Hospital, Harbin 150036 (China); Zhao, Qingjie, E-mail: zhaoqingjie2013@163.com [Department of Neurology, The First Affiliated School of Harbin Medical University, Harbin 150001 (China)

    2014-09-26

    Graphical abstract: - Highlights: • Alcohol upregulates miR-339-5p expression. • miR-339-5p inhibits the NF-kB pathway. • miR-339-5p interacts with and blocks activity of IKK-beat and IKK-epsilon. • miR-339-5p modulates IL-1β, IL-6 and TNF-α. - Abstract: Alcohol-induced neuroinflammation is mediated by the innate immunesystem. Pro-inflammatory responses to alcohol are modulated by miRNAs. The miRNA miR-339-5p has previously been found to be upregulated in alcohol-induced neuroinflammation. However, little has been elucidated on the regulatory functions of this miRNA in alcohol-induced neuroinflammation. We investigated the function of miR-339-5p in alcohol exposed brain tissue and isolated microglial cells using ex vivo and in vitro techniques. Our results show that alcohol induces transcription of miR 339-5p, IL-6, IL-1β and TNF-α in mouse brain tissue and isolated microglial cells by activating NF-κB. Alcohol activation of NF-κB allows for nuclear translocation of the NF-κB subunit p65 and expression of pro-inflammatory mediators. miR-339-5p inhibited expression of these pro-inflammatory factors through the NF-κB pathway by abolishing IKK-β and IKK-ε activity.

  16. A role for NF-κB–dependent gene transactivation in sunburn

    Science.gov (United States)

    Abeyama, Kazuhiro; Eng, William; Jester, James V.; Vink, Arie A.; Edelbaum, Dale; Cockerell, Clay J.; Bergstresser, Paul R.; Takashima, Akira

    2000-01-01

    Exposure of skin to ultraviolet (UV) radiation is known to induce NF-κB activation, but the functional role for this pathway in UV-induced cutaneous inflammation remains uncertain. In this study, we examined whether experimentally induced sunburn reactions in mice could be prevented by blocking UV-induced, NF-κB–dependent gene transactivation with oligodeoxynucleotides (ODNs) containing the NF-κB cis element (NF-κB decoy ODNs). UV-induced secretion of IL-1, IL-6, TNF-α, and VEGF by skin-derived cell lines was inhibited by the decoy ODNs, but not by the scrambled control ODNs. Systemic or local injection of NF-κB decoy ODNs also inhibited cutaneous swelling responses to UV irradiation. Moreover, local UV-induced inflammatory changes (swelling, leukocyte infiltration, epidermal hyperplasia, and accumulation of proinflammatory cytokines) were all inhibited specifically by topically applied decoy ODNs. Importantly, these ODNs had no effect on alternative types of cutaneous inflammation caused by irritant or allergic chemicals. These results indicate that sunburn reactions culminate from inflammatory events that are triggered by UV-activated transcription of NF-κB target genes, rather than from nonspecific changes associated with tissue damage. PMID:10862790

  17. Cyclin D3 interacts with human activating transcription factor 5 and potentiates its transcription activity

    International Nuclear Information System (INIS)

    Liu Wenjin; Sun Maoyun; Jiang Jianhai; Shen Xiaoyun; Sun Qing; Liu Weicheng; Shen Hailian; Gu Jianxin

    2004-01-01

    The Cyclin D3 protein is a member of the D-type cyclins. Besides serving as cell cycle regulators, D-type cyclins have been reported to be able to interact with several transcription factors and modulate their transcriptional activations. Here we report that human activating transcription factor 5 (hATF5) is a new interacting partner of Cyclin D3. The interaction was confirmed by in vivo coimmunoprecipitation and in vitro binding analysis. Neither interaction between Cyclin D1 and hATF5 nor interaction between Cyclin D2 and hATF5 was observed. Confocal microscopy analysis showed that Cyclin D3 could colocalize with hATF5 in the nuclear region. Cyclin D3 could potentiate hATF5 transcriptional activity independently of its Cdk4 partner. But Cyclin D1 and Cyclin D2 had no effect on hATF5 transcriptional activity. These data provide a new clue to understand the new role of Cyclin D3 as a transcriptional regulator

  18. Amelioration of Mitochondrial Dysfunction-Induced Insulin Resistance in Differentiated 3T3-L1 Adipocytes via Inhibition of NF-κB Pathways

    Directory of Open Access Journals (Sweden)

    Mohamad Hafizi Abu Bakar

    2014-12-01

    Full Text Available A growing body of evidence suggests that activation of nuclear factor kappa B (NF-κB signaling pathways is among the inflammatory mechanism involved in the development of insulin resistance and chronic low-grade inflammation in adipose tissues derived from obese animal and human subjects. Nevertheless, little is known about the roles of NF-κB pathways in regulating mitochondrial function of the adipose tissues. In the present study, we sought to investigate the direct effects of celastrol (potent NF-κB inhibitor upon mitochondrial dysfunction-induced insulin resistance in 3T3-L1 adipocytes. Celastrol ameliorates mitochondrial dysfunction by altering mitochondrial fusion and fission in adipocytes. The levels of oxidative DNA damage, protein carbonylation and lipid peroxidation were down-regulated. Further, the morphology and quantification of intracellular lipid droplets revealed the decrease of intracellular lipid accumulation with reduced lipolysis. Moreover, massive production of the pro-inflammatory mediators tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β were markedly depleted. Insulin-stimulated glucose uptake activity was restored with the enhancement of insulin signaling pathways. This study signified that the treatments modulated towards knockdown of NF-κB transcription factor may counteract these metabolic insults exacerbated in our model of synergy between mitochondrial dysfunction and inflammation. These results demonstrate for the first time that NF-κB inhibition modulates mitochondrial dysfunction induced insulin resistance in 3T3-L1 adipocytes.

  19. Modulation of DNA binding by gene-specific transcription factors.

    Science.gov (United States)

    Schleif, Robert F

    2013-10-01

    The transcription of many genes, particularly in prokaryotes, is controlled by transcription factors whose activity can be modulated by controlling their DNA binding affinity. Understanding the molecular mechanisms by which DNA binding affinity is regulated is important, but because forming definitive conclusions usually requires detailed structural information in combination with data from extensive biophysical, biochemical, and sometimes genetic experiments, little is truly understood about this topic. This review describes the biological requirements placed upon DNA binding transcription factors and their consequent properties, particularly the ways that DNA binding affinity can be modulated and methods for its study. What is known and not known about the mechanisms modulating the DNA binding affinity of a number of prokaryotic transcription factors, including CAP and lac repressor, is provided.

  20. Transcriptional repression of BODENLOS by HD-ZIP transcription factor HB5 in Arabidopsis thaliana.

    NARCIS (Netherlands)

    Smet, De I.; Lau, S.; Ehrismann, J.S.; Axiotis, I.; Kolb, M.; Kientz, M.; Weijers, D.; Jürgens, G.

    2013-01-01

    In Arabidopsis thaliana, the phytohormone auxin is an important patterning agent during embryogenesis and post-embryonic development, exerting effects through transcriptional regulation. The main determinants of the transcriptional auxin response machinery are AUXIN RESPONSE FACTOR (ARF)

  1. A non-canonical Flt3ITD/NF-κB signaling pathway represses DAPK1 in acute myeloid leukemia (AML)

    Science.gov (United States)

    Shanmugam, Rajasubramaniam; Sayar, Hamid; Suvannasankha, Attaya; Goswami, Chirayu; Li, Lang; Gupta, Sushil; Cardoso, Angelo A.; Baghdadi, Tareq Al; Sargent, Katie J.; Cripe, Larry D.; Kalvakolanu, Dhananjaya V.; Boswell, H. Scott

    2014-01-01

    Purpose DAPK1, a tumor suppressor, is a rate-limiting effector in an ER stress-dependent apoptotic pathway. Its expression is epigenetically suppressed in several tumors. A mechanistic basis for epigenetic/transcriptional repression of DAPK1 was investigated in certain forms of AML with poor prognosis, which lacked ER stress-induced apoptosis. Experimental Design Heterogeneous primary AMLs were screened to identify a subgroup with Flt3ITD in which repression of DAPK1, among NF-κB- and c- jun-responsive genes, was studied. RNAi knockdown studies were performed in Flt3ITD+ve cell line, MV-4-11, to establish genetic epistasis in the pathway Flt3ITD-TAK1-DAPK1 repression, and chromatin immunoprecipitations were performed to identify proximate effector proteins, including TAK1-activated p52NF-κB, at the DAPK1 locus. Results AMLs characterized by normal karyotype with Flt3ITD were found to have 10-100-fold lower DAPK1 transcripts normalized to the expression of c-jun, a transcriptional activator of DAPK1, as compared to a heterogeneous cytogenetic category. Meis1, a c-jun-responsive adverse AML prognostic gene signature was also measured as control. These Flt3ITD+ve AMLs over-express relB, a transcriptional repressor, which forms active heterodimers with p52NF-κB. Chromatin immunoprecipitation assays identified p52NF-κB binding to the DAPK1 promoter along with HDAC2 and HDAC6 in the Flt3ITD+ve human AML cell line MV-4-11. Knockdown of p52NF-κB or its upstream regulator, NIK, de-repressed DAPK1. DAPK1-repressed primary Flt3ITD+ve AMLs had selective nuclear activation of p52NF-κB. Conclusions Flt3ITD promotes a non-canonical pathway via TAK1 and p52NF-κB to suppress DAPK1 in association with HDACs, which explains DAPK1 repression in Flt3ITD+ve AML. PMID:22096027

  2. HMBA Enhances Prostratin-Induced Activation of Latent HIV-1 via Suppressing the Expression of Negative Feedback Regulator A20/TNFAIP3 in NF-κB Signaling

    Directory of Open Access Journals (Sweden)

    Duchu Chen

    2016-01-01

    Full Text Available In the past decade, much emphasis has been put on the transcriptional activation of HIV-1, which is proposed as a promised strategy for eradicating latent HIV-1 provirus. Two drugs, prostratin and hexamethylene bisacetamide (HMBA, have shown potent effects as inducers for releasing HIV-1 latency when used alone or in combination, although their cellular target(s are currently not well understood, especially under drug combination. Here, we have shown that HMBA and prostratin synergistically release HIV-1 latency via different mechanisms. While prostratin strongly stimulates HMBA-induced HIV-1 transcription via improved P-TEFb activation, HMBA is capable of boosting NF-κB-dependent transcription initiation by suppressing prostratin-induced expression of the deubiquitinase A20, a negative feedback regulator in the NF-κB signaling pathway. In addition, HMBA was able to increase prostratin-induced phosphorylation and degradation of NF-κB inhibitor IκBα, thereby enhancing and prolonging prostratin-induced nuclear translocation of NF-κB, a prerequisite for stimulation of transcription initiation. Thus, by blocking the negative feedback circuit, HMBA functions as a signaling enhancer of the NF-κB signaling pathway.

  3. Inhibitors of nuclear factor kappa B cause apoptosis in cultured macrophages

    Directory of Open Access Journals (Sweden)

    E. E. Mannick

    1997-01-01

    Full Text Available The precise role of the transcription factor nuclear factor kappa B (NF- κB in the regulation of cell survival and cell death is still unresolved and may depend on cell type and position in the cell cycle. The aim of this study was to determine if three pharmacologic inhibitors of NF-κB, pyrrolidine dithiocarbamate, N-tosyl-L-lysl chloromethyl ketone and calpain I inhibitor, induce apoptosis in a murine macrophage cell line (RAW 264.7 at doses similar to those required for NF-κB inhibition. We found that each of the three inhibitors resulted in a dose- and time-dependent increase in morphologic indices of apoptosis in unstimulated, LPS-stimulated and TNF-stimulated cells. Lethal doses were consistent with those required for NF- κB inhibition. We conclude that nuclear NF-κB activation may represent an important survival mechanism in macrophages.

  4. Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes.

    Science.gov (United States)

    Riechmann, J L; Heard, J; Martin, G; Reuber, L; Jiang, C; Keddie, J; Adam, L; Pineda, O; Ratcliffe, O J; Samaha, R R; Creelman, R; Pilgrim, M; Broun, P; Zhang, J Z; Ghandehari, D; Sherman, B K; Yu, G

    2000-12-15

    The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

  5. 27-Oxygenated cholesterol induces expression of CXCL8 in macrophages via NF-κB and CD88

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun-Mi, E-mail: lala1647@hanmail.net [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Lee, Chung Won, E-mail: vasculardoctorlee@gmail.com [Department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital, Pusan 602-739 (Korea, Republic of); Kim, Bo-Young, E-mail: kimboyoung@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Jung, Young-Suk, E-mail: youngjung@pusan.ac.kr [College of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Eo, Seong-Kug, E-mail: vetvirus@chonbuk.ac.kr [College of Veterinary Medicine and Bio-Safety Research Institute, Chonbuk National University, Iksan, Jeonbuk 570-752 (Korea, Republic of); Park, Young Chul, E-mail: ycpark@pusan.ac.kr [Department of Microbiology & Immunology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Kim, Koanhoi, E-mail: koanhoi@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of)

    2015-08-07

    We attempted to determine the effects of a milieu rich in cholesterol molecules on expression of chemokine CXCL8. A high-cholesterol diet led to an increased transcription of the IL-8 gene in the arteries and elevated levels of CXCL8 in sera of ApoE{sup −/−} mice, compared with those of wild-type C57BL/6 mice. Treatment of THP-1 monocyte/macrophage cells with 27-hydroxycholesterol (27OHChol) resulted in transcription of the IL-8 gene and increased secretion of its corresponding gene product whereas cholesterol did not induce expression of CXCL8 in THP-1 cells. 27OHChol-induced transcription of the IL-8 gene was blocked by cycloheximide, but not by polymyxin B. Treatment of THP-1 cells with 27OHChol caused translocation of p65 NF-κB subunit into the nucleus and up-regulation of CD88. Inhibition of NF-κB and CD88 using SN50 and W-54011, respectively, resulted in reduced transcription of the IL-8 gene and attenuated secretion of CXCL8 induced by 27OHChol. We propose that oxidatively modified cholesterol like 27OHChol, rather than cholesterol, is responsible for sustained expression of CXCL8 in monocytes/macrophages in atherosclerotic arteries. - Highlights: • Consumption of a high-cholesterol diet leads to increased CXCL8 expression in ApoE{sup −/−} mice. • 27OHChol, but not cholesterol, up-regulates expression of CXCL8 in macrophages. • 27OHChol enhances nuclear translocation of NF-κB and expression of CD88 in macrophages. • Inhibition of NF-κB or CD88 results in decreased CXCL8 expression induced by 27OHChol. • 27OHChol up-regulates CXCL8 expression via NF-κB and CD88 in macrophages.

  6. BACH transcription factors in innate and adaptive immunity.

    Science.gov (United States)

    Igarashi, Kazuhiko; Kurosaki, Tomohiro; Roychoudhuri, Rahul

    2017-07-01

    BTB and CNC homology (BACH) proteins are transcriptional repressors of the basic region leucine zipper (bZIP) transcription factor family. Recent studies indicate widespread roles of BACH proteins in controlling the development and function of the innate and adaptive immune systems, including the differentiation of effector and memory cells of the B and T cell lineages, CD4 + regulatory T cells and macrophages. Here, we emphasize similarities at a molecular level in the cell-type-specific activities of BACH factors, proposing that competitive interactions of BACH proteins with transcriptional activators of the bZIP family form a common mechanistic theme underlying their diverse actions. The findings contribute to a general understanding of how transcriptional repressors shape lineage commitment and cell-type-specific functions through repression of alternative lineage programmes.

  7. Th17-type cytokines, IL-6 and TNF-α synergistically activate STAT3 and NF-kB to promote colorectal cancer cell growth.

    Science.gov (United States)

    De Simone, V; Franzè, E; Ronchetti, G; Colantoni, A; Fantini, M C; Di Fusco, D; Sica, G S; Sileri, P; MacDonald, T T; Pallone, F; Monteleone, G; Stolfi, C

    2015-07-01

    Colorectal cancers (CRCs) often show a dense infiltrate of cytokine-producing immune/inflammatory cells. The exact contribution of each immune cell subset and cytokine in the activation of the intracellular pathways sustaining CRC cell growth is not understood. Herein, we isolate tumor-infiltrating leukocytes (TILs) and lamina propria mononuclear cells (LPMCs) from the tumor area and the macroscopically unaffected, adjacent, colonic mucosa of patients who underwent resection for sporadic CRC and show that the culture supernatants of TILs, but not of LPMCs, potently enhance the growth of human CRC cell lines through the activation of the oncogenic transcription factors signal transducer and activator of transcription 3 (STAT3) and nuclear factor-kappa B (NF-kB). Characterization of immune cell complexity of TILs and LPMCs reveals no differences in the percentages of T cells, natural killer T cells, natural killer (NK) cells, macrophages and B cells. However, T cells from TILs show a functional switch compared with those from LPMCs to produce large amounts of T helper type 17 (Th17)-related cytokines (that is, interleukin-17A (IL-17A), IL-17F, IL-21 and IL-22), tumor necrosis factor-α (TNF-α) and IL-6. Individual neutralization of IL-17A, IL-17F, IL-21, IL-22, TNF-α or IL-6 does not change TIL-derived supernatant-driven STAT3 and NF-kB activation, as well as their proproliferative effect in CRC cells. In contrast, simultaneous neutralization of both IL-17A and TNF-α, which abrogates NF-kB signaling, and IL-22 and IL-6, which abrogates STAT3 signaling, reduces the mitogenic effect of supernatants in CRC cells. IL-17A, IL-21, IL-22, TNF-α and IL-6 are also produced in excess in the early colonic lesions in a mouse model of sporadic CRC, associated with enhanced STAT3/NF-kB activation. Mice therapeutically given BP-1-102, an orally bioavailable compound targeting STAT3/NF-kB activation and cross-talk, exhibit reduced colon tumorigenesis and diminished expression of

  8. Thirty-seven transcription factor genes differentially respond to a ...

    Indian Academy of Sciences (India)

    Plant transcription factors and insect defence si. Thirty-seven transcription factor genes differentially respond to a harpin protein and affect resistance to the green peach aphid in Arabidopsis. HUNLIN. PIN. RUOXUE LIŲ, BEIBEI LÜ, XIAOMENG WANG, CHUNLING ZHANG, SHUPING ZHANG, JUN QIAN, LEI CHEN,.

  9. E2F1-Mediated Induction of NFYB Attenuates Apoptosis via Joint Regulation of a Pro-Survival Transcriptional Program.

    Directory of Open Access Journals (Sweden)

    Xiaolei Jiang

    Full Text Available The E2F1 transcription factor regulates cell proliferation and apoptosis through the control of a considerable variety of target genes. Previous work has detailed the role of other transcription factors in mediating the specificity of E2F function. Here we identify the NF-YB transcription factor as a novel direct E2F1 target. Genome-wide expression analysis of the effects of NFYB knockdown on E2F1-mediated transcription identified a large group of genes that are co-regulated by E2F1 and NFYB. We also provide evidence that knockdown of NFYB enhances E2F1-induced apoptosis, suggesting a pro-survival function of the NFYB/E2F1 joint transcriptional program. Bioinformatic analysis suggests that deregulation of these NFY-dependent E2F1 target genes might play a role in sarcomagenesis as well as drug resistance.

  10. Structural Fingerprints of Transcription Factor Binding Site Regions

    Directory of Open Access Journals (Sweden)

    Peter Willett

    2009-03-01

    Full Text Available Fourier transforms are a powerful tool in the prediction of DNA sequence properties, such as the presence/absence of codons. We have previously compiled a database of the structural properties of all 32,896 unique DNA octamers. In this work we apply Fourier techniques to the analysis of the structural properties of human chromosomes 21 and 22 and also to three sets of transcription factor binding sites within these chromosomes. We find that, for a given structural property, the structural property power spectra of chromosomes 21 and 22 are strikingly similar. We find common peaks in their power spectra for both Sp1 and p53 transcription factor binding sites. We use the power spectra as a structural fingerprint and perform similarity searching in order to find transcription factor binding site regions. This approach provides a new strategy for searching the genome data for information. Although it is difficult to understand the relationship between specific functional properties and the set of structural parameters in our database, our structural fingerprints nevertheless provide a useful tool for searching for function information in sequence data. The power spectrum fingerprints provide a simple, fast method for comparing a set of functional sequences, in this case transcription factor binding site regions, with the sequences of whole chromosomes. On its own, the power spectrum fingerprint does not find all transcription factor binding sites in a chromosome, but the results presented here show that in combination with other approaches, this technique will improve the chances of identifying functional sequences hidden in genomic data.

  11. Transient degradation of NF-κB proteins in macrophages after interaction with mast cell granules

    Directory of Open Access Journals (Sweden)

    Noriko Ito

    1998-01-01

    Full Text Available The exposure of the macrophage cell line, J774 to mast cell granules (MCG led to the form ation of altered nuclear transcription factor proteins (NFκBx, which had faster electrophoretic mobility than the p50 homodimer of NF-κB, but retained comparable DNA binding capacity. Antibodies to N-terminal peptides of p50, p52, p65 or c-Rel supershifted only a fraction of NF-κBx. Western blot analyses revealed that nuclear p65 and c-Rel were progressively degraded after exposure to MCG, whereas nuclear p50 appeared to be unaffected. In contrast, cytoplasmic p50, p65, c-Rel as well as IkBα remained intact after MCG treatment, although p52 was clearly degraded. In comparison to J774 cells, incubation of m ouse peritoneal macrophages with MCG resulted in more extensive alterations to NF-κB proteins. The alterations in NF-κB proteins did not affect the expression of inducible nitric oxide synthase (iNOS or TNF-α mRNA in J774 cells. These data indicate that exposure of J774 cells to MCG leads to generation of altered nuclear p52, p65 and c-Rel, which retain intact N-terminal peptides, specific oligonucleotide binding and transactivating activity. On the other hand, in peritoneal macrophages, MCG induce more extensive modifications to NF-κB proteins with associated inhibition of iNOS or TNF-α mRNA expression.

  12. Mechanism by which nuclear factor-kappa beta (NF-kB regulates ovine fetal pulmonary vascular smooth muscle cell proliferation

    Directory of Open Access Journals (Sweden)

    Uchenna D. Ogbozor

    2015-09-01

    Full Text Available Platelet activating factor (PAF modulates ovine fetal pulmonary hemodynamic. PAF acts through its receptors (PAFR in pulmonary vascular smooth muscle cells (PVSMC to phosphorylate and induce nuclear translocation of NF-kB p65 leading to PVSMC proliferation. However, the interaction of NF-kB p65 and PAF in the nuclear domain to effect PVSMC cell growth is not clearly defined. We used siRNA-dependent translation initiation arrest to study a mechanism by which NF-kB p65 regulates PAF stimulation of PVSMC proliferation. Our hypotheses are: (a PAF induces NF-kB p65 DNA binding and (b NF-kB p65 siRNA attenuates PAF stimulation of PVSMC proliferation. For DNA binding, cells were fed 10 nM PAF with and without PAFR antagonists WEB 2170, CV 3988 or BN 52021 and incubated for 12 h. DNA binding was measured by specific ELISA. For NF-kB p65 siRNA effect, starved cells transfected with the siRNA were incubated for 24 h with and without 10 nM PAF. Cell proliferation was measured by DNA synthesis while expression of NF-kB p65 and PAFR protein was measured by Western blotting. In both studies, the effect of 10% FBS alone was used as the positive control. In general, PAF stimulated DNA binding which was inhibited by PAFR antagonists. siRNAs to NF-kB p65 and PAFR significantly attenuated cell proliferation compared to 10% FBS and PAF effect. Inclusion of PAF in siRNA-treated cells did not reverse inhibitory effect of NF-kB p65 siRNA on DNA synthesis. PAFR expression was inhibited in siRNA-treated cells. These data show that PAF-stimulation of PVSMC proliferation occurs via a PAFR-NF-kB p65 linked pathway.

  13. Mechanism by which nuclear factor-kappa beta (NF-kB) regulates ovine fetal pulmonary vascular smooth muscle cell proliferation.

    Science.gov (United States)

    Ogbozor, Uchenna D; Opene, Michael; Renteria, Lissette S; McBride, Shaemion; Ibe, Basil O

    2015-09-01

    Platelet activating factor (PAF) modulates ovine fetal pulmonary hemodynamic. PAF acts through its receptors (PAFR) in pulmonary vascular smooth muscle cells (PVSMC) to phosphorylate and induce nuclear translocation of NF-kB p65 leading to PVSMC proliferation. However, the interaction of NF-kB p65 and PAF in the nuclear domain to effect PVSMC cell growth is not clearly defined. We used siRNA-dependent translation initiation arrest to study a mechanism by which NF-kB p65 regulates PAF stimulation of PVSMC proliferation. Our hypotheses are: (a) PAF induces NF-kB p65 DNA binding and (b) NF-kB p65 siRNA attenuates PAF stimulation of PVSMC proliferation. For DNA binding, cells were fed 10 nM PAF with and without PAFR antagonists WEB 2170, CV 3988 or BN 52021 and incubated for 12 h. DNA binding was measured by specific ELISA. For NF-kB p65 siRNA effect, starved cells transfected with the siRNA were incubated for 24 h with and without 10 nM PAF. Cell proliferation was measured by DNA synthesis while expression of NF-kB p65 and PAFR protein was measured by Western blotting. In both studies, the effect of 10% FBS alone was used as the positive control. In general, PAF stimulated DNA binding which was inhibited by PAFR antagonists. siRNAs to NF-kB p65 and PAFR significantly attenuated cell proliferation compared to 10% FBS and PAF effect. Inclusion of PAF in siRNA-treated cells did not reverse inhibitory effect of NF-kB p65 siRNA on DNA synthesis. PAFR expression was inhibited in siRNA-treated cells. These data show that PAF-stimulation of PVSMC proliferation occurs via a PAFR-NF-kB p65 linked pathway.

  14. Butyrate attenuates lipopolysaccharide-induced inflammation in intestinal cells and Crohn's mucosa through modulation of antioxidant defense machinery.

    Directory of Open Access Journals (Sweden)

    Ilaria Russo

    Full Text Available Oxidative stress plays an important role in the pathogenesis of inflammatory bowel disease (IBD, including Crohn's disease (CrD. High levels of Reactive Oxygen Species (ROS induce the activation of the redox-sensitive nuclear transcription factor kappa-B (NF-κB, which in turn triggers the inflammatory mediators. Butyrate decreases pro-inflammatory cytokine expression by the lamina propria mononuclear cells in CrD patients via inhibition of NF-κB activation, but how it reduces inflammation is still unclear. We suggest that butyrate controls ROS mediated NF-κB activation and thus mucosal inflammation in intestinal epithelial cells and in CrD colonic mucosa by triggering intracellular antioxidant defense systems. Intestinal epithelial Caco-2 cells and colonic mucosa from 14 patients with CrD and 12 controls were challenged with or without lipopolysaccaride from Escherichia coli (EC-LPS in presence or absence of butyrate for 4 and 24 h. The effects of butyrate on oxidative stress, p42/44 MAP kinase phosphorylation, p65-NF-κB activation and mucosal inflammation were investigated by real time PCR, western blot and confocal microscopy. Our results suggest that EC-LPS challenge induces a decrease in Gluthation-S-Transferase-alpha (GSTA1/A2 mRNA levels, protein expression and catalytic activity; enhanced levels of ROS induced by EC-LPS challenge mediates p65-NF-κB activation and inflammatory response in Caco-2 cells and in CrD colonic mucosa. Furthermore butyrate treatment was seen to restore GSTA1/A2 mRNA levels, protein expression and catalytic activity and to control NF-κB activation, COX-2, ICAM-1 and the release of pro-inflammatory cytokine. In conclusion, butyrate rescues the redox machinery and controls the intracellular ROS balance thus switching off EC-LPS induced inflammatory response in intestinal epithelial cells and in CrD colonic mucosa.

  15. NAC Transcription Factors in Stress Responses and Senescence

    DEFF Research Database (Denmark)

    O'Shea, Charlotte

    Plant-specific NAM/ATAF/CUC (NAC) transcription factors have recently received considerable attention due to their significant roles in plant development and stress signalling. This interest has resulted in a number of physiological, genetic and cell biological studies of their functions. Some...... of these studies have also revealed emerging gene regulatory networks and protein-protein interaction networks. However, structural studies relating structure to function are lagging behind. Structure-function analysis of the NAC transcription factors has therefore been the main focus of this PhD thesis...... not involve significant folding-upon-binding but fuzziness or an extended ANAC046 region. The ANAC046 regulatory domain functions as an entropic chain with a bait for interactions with for example RCD1. RCD1 interacts with transcription factors from several different families, and the large stress...

  16. Cross-Family Transcription Factor Interactions

    NARCIS (Netherlands)

    Bemer, Marian; Dijk, van Aalt-Jan; Immink, Richard G.H.; Angenent, Gerco C.

    2017-01-01

    Specific and dynamic gene expression strongly depends on transcription factor (TF) activity and most plant TFs function in a combinatorial fashion. They can bind to DNA and control the expression of the corresponding gene in an additive fashion or cooperate by physical interactions, forming larger

  17. Up-stream events in the nuclear factor κB activation cascade in response to sparsely ionizing radiation

    Science.gov (United States)

    Hellweg, Christine E.; Langen, Britta; Klimow, Galina; Ruscher, Roland; Schmitz, Claudia; Baumstark-Khan, Christa; Reitz, Günther

    2009-10-01

    Radiation is a potentially limiting factor for manned long-term space missions. Prolonged exposure to galactic cosmic rays may shorten the healthy life-span after return to Earth due to cancer induction. During the mission, a solar flare can be life threatening. For better risk estimation and development of appropriate countermeasures, the study of the cellular radiation response is necessary. Since apoptosis may be a mechanism the body uses to eliminate damaged cells, the induction by cosmic radiation of the nuclear anti-apoptotic transcription factor nuclear factor κB (NF-κB) could influence the cancer risk of astronauts exposed to cosmic radiation by improving the survival of radiation-damaged cells. In previous studies using a screening assay for the detection of NF-κB-dependent gene induction (HEK-pNF-κB-d2EGFP/Neo cells), the activation of this transcription factor by heavy ions was shown [Baumstark-Khan, C., Hellweg, C.E., Arenz, A., Meier, M.M. Cellular monitoring of the nuclear factor kappa B pathway for assessment of space environmental radiation. Radiat. Res. 164, 527-530, 2005]. Studies with NF-κB inhibitors can map functional details of the NF-κB pathway and the influence of radiation-induced NF-κB activation on various cellular outcomes such as survival or cell cycle arrest. In this work, the efficacy and cytotoxicity of four different NF-κB inhibitors, caffeic acid phenethyl ester (CAPE), capsaicin, the proteasome inhibitor MG-132, and the cell permeable peptide NF-κB SN50 were analyzed using HEK-pNF-κB-d2EGFP/Neo cells. In the recommended concentration range, only CAPE displayed considerable cytotoxicity. CAPE and capsaicin partially inhibited NF-κB activation by the cytokine tumor necrosis factor α. MG-132 completely abolished the activation and was therefore used for experiments with X-rays. NF-κB SN-50 could not reduce NF-κB dependent expression of the reporter destabilized Enhanced Green Fluorescent Protein (d2EGFP). MG-132

  18. Transcription factor interplay in T helper cell differentiation

    Science.gov (United States)

    Evans, Catherine M.

    2013-01-01

    The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity. PMID:23878131

  19. Transcription factor interplay in T helper cell differentiation.

    Science.gov (United States)

    Evans, Catherine M; Jenner, Richard G

    2013-11-01

    The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity.

  20. Ganoderma lucidum suppresses growth of breast cancer cells through the inhibition of Akt/NF-kappaB signaling.

    Science.gov (United States)

    Jiang, Jiahua; Slivova, Veronika; Harvey, Kevin; Valachovicova, Tatiana; Sliva, Daniel

    2004-01-01

    Ganoderma lucidum (Reishi, Lingzhi) is a popular Asian mushroom that has been used for more than 2 millennia for the general promotion of health and was therefore called the "Mushroom of Immortality." Ganoderma lucidum was also used in traditional Chinese medicine to prevent or treat a variety of diseases, including cancer. We previously demonstrated that Ganoderma lucidum suppresses the invasive behavior of breast cancer cells by inhibiting the transcription factor NF-kappaB. However, the molecular mechanisms responsible for the inhibitory effects of Ganoderma lucidum on the growth of highly invasive and metastatic breast cancer cells has not been fully elucidated. Here, we show that Ganoderma lucidum inhibits proliferation of breast cancer MDA-MB-231 cells by downregulating Akt/NF-kappaB signaling. Ganoderma lucidum suppresses phosphorylation of Akt on Ser473 and downregulates the expression of Akt, which results in the inhibition of NF-kappaB activity in MDA-MB-231 cells. The biological effect of Ganoderma lucidum was demonstrated by cell cycle arrest at G0/G1, which was the result of the downregulation of expression of NF-kappaB-regulated cyclin D1, followed by the inhibition of cdk4. Our results suggest that Ganoderma lucidum inhibits the growth of MDA-MB-231 breast cancer cells by modulating Akt/NF-kappaB signaling and could have potential therapeutic use for the treatment of breast cancer.

  1. Osthole inhibits the invasive ability of human lung adenocarcinoma cells via suppression of NF-κB-mediated matrix metalloproteinase-9 expression

    Energy Technology Data Exchange (ETDEWEB)

    Kao, Shang-Jyh [Department of Chest Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); School of Respiratory Therapy, Taipei Medical University, Taipei Taiwan (China); Su, Jen-Liang [Graduate Institute of Cancer Biology, College of Medicine, China Medical University, Taichung, Taiwan (China); Center for Molecular Medicine, China Medical University Hospital, Taichung, Taiwan (China); Department of Biotechnology, Asia University, Taichung, Taiwan (China); Chen, Chi-Kuan [Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Yu, Ming-Chih; Bai, Kuan-Jen; Chang, Jer-Hua [Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan (China); Bien, Mauo-Ying [School of Respiratory Therapy, Taipei Medical University, Taipei Taiwan (China); Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan (China); Yang, Shun-Fa [Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Chien, Ming-Hsien, E-mail: mhchien1976@gmail.com [Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China)

    2012-05-15

    The induction of matrix metalloproteinase (MMP)-9 is particularly important for the invasiveness of various cancer cells. Osthole, a natural coumarin derivative extracted from traditional Chinese medicines, is known to inhibit the proliferation of a variety of tumor cells, but the effect of osthole on the invasiveness of tumor cells is largely unknown. This study determines whether and by what mechanism osthole inhibits invasion in CL1-5 human lung adenocarcinoma cells. Herein, we found that osthole effectively inhibited the migratory and invasive abilities of CL1-5 cells. A zymographic assay showed that osthole inhibited the proteolytic activity of MMP-9 in CL1-5 cells. Inhibition of migration, invasion, and MMP2 and/or MMP-9 proteolytic activities was also observed in other lung adenocarcinoma cell lines (H1299 and A549). We further found that osthole inhibited MMP-9 expression at the messenger RNA and protein levels. Moreover, a chromatin immunoprecipitation assay showed that osthole inhibited the transcriptional activity of MMP-9 by suppressing the DNA binding activity of nuclear factor (NF)-κB in the MMP-9 promoter. Using reporter assays with point-mutated promoter constructs further confirmed that the inhibitory effect of osthole requires an NF-κB binding site on the MMP-9 promoter. Western blot and immunofluorescence assays demonstrated that osthole inhibited NF-κB activity by inhibiting IκB-α degradation and NF-κB p65 nuclear translocation. In conclusion, we demonstrated that osthole inhibits NF-κB-mediated MMP-9 expression, resulting in suppression of lung cancer cell invasion and migration, and osthole might be a potential agent for preventing the invasion and metastasis of lung cancer. -- Highlights: ► Osthole treatment inhibits lung adenocarcinoma cells migration and invasion. ► Osthole reduces the expression and proteolytic activity of MMP-9. ► Osthole inhibits MMP-9 transcription via suppression of NF-κB binding activity. ► Osthole

  2. Enhanceosomes as integrators of hypoxia inducible factor (HIF) and other transcription factors in the hypoxic transcriptional response.

    Science.gov (United States)

    Pawlus, Matthew R; Hu, Cheng-Jun

    2013-09-01

    Hypoxia is a prevalent attribute of the solid tumor microenvironment that promotes the expression of genes through posttranslational modifications and stabilization of alpha subunits (HIF1α and HIF2α) of hypoxia-inducible factors (HIFs). Despite significant similarities, HIF1 (HIF1α/ARNT) and HIF2 (HIF2α/ARNT) activate common as well as unique target genes and exhibit different functions in cancer biology. More surprisingly, accumulating data indicates that the HIF1- and/or HIF2-mediated hypoxia responses can be oncogenic as well as tumor suppressive. While the role of HIF in the hypoxia response is well established, recent data support the concept that HIF is necessary, but not sufficient for the hypoxic response. Other transcription factors that are activated by hypoxia are also required for the HIF-mediated hypoxia response. HIFs, other transcription factors, co-factors and RNA poll II recruited by HIF and other transcription factors form multifactorial enhanceosome complexes on the promoters of HIF target genes to activate hypoxia inducible genes. Importantly, HIF1 or HIF2 requires distinct partners in activating HIF1 or HIF2 target genes. Because HIF enhanceosome formation is required for the gene activation and distinct functions of HIF1 and HIF2 in tumor biology, disruption of the HIF1 or HIF2 specific enhanceosome complex may prove to be a beneficial strategy in tumor treatment in which tumor growth is specifically dependent upon HIF1 or HIF2 activity. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. DNA Binding by the Ribosomal DNA Transcription Factor Rrn3 Is Essential for Ribosomal DNA Transcription*

    Science.gov (United States)

    Stepanchick, Ann; Zhi, Huijun; Cavanaugh, Alice H.; Rothblum, Katrina; Schneider, David A.; Rothblum, Lawrence I.

    2013-01-01

    The human homologue of yeast Rrn3 is an RNA polymerase I-associated transcription factor that is essential for ribosomal DNA (rDNA) transcription. The generally accepted model is that Rrn3 functions as a bridge between RNA polymerase I and the transcription factors bound to the committed template. In this model Rrn3 would mediate an interaction between the mammalian Rrn3-polymerase I complex and SL1, the rDNA transcription factor that binds to the core promoter element of the rDNA. In the course of studying the role of Rrn3 in recruitment, we found that Rrn3 was in fact a DNA-binding protein. Analysis of the sequence of Rrn3 identified a domain with sequence similarity to the DNA binding domain of heat shock transcription factor 2. Randomization, or deletion, of the amino acids in this region in Rrn3, amino acids 382–400, abrogated its ability to bind DNA, indicating that this domain was an important contributor to DNA binding by Rrn3. Control experiments demonstrated that these mutant Rrn3 constructs were capable of interacting with both rpa43 and SL1, two other activities demonstrated to be essential for Rrn3 function. However, neither of these Rrn3 mutants was capable of functioning in transcription in vitro. Moreover, although wild-type human Rrn3 complemented a yeast rrn3-ts mutant, the DNA-binding site mutant did not. These results demonstrate that DNA binding by Rrn3 is essential for transcription by RNA polymerase I. PMID:23393135

  4. DNA binding by the ribosomal DNA transcription factor rrn3 is essential for ribosomal DNA transcription.

    Science.gov (United States)

    Stepanchick, Ann; Zhi, Huijun; Cavanaugh, Alice H; Rothblum, Katrina; Schneider, David A; Rothblum, Lawrence I

    2013-03-29

    The human homologue of yeast Rrn3 is an RNA polymerase I-associated transcription factor that is essential for ribosomal DNA (rDNA) transcription. The generally accepted model is that Rrn3 functions as a bridge between RNA polymerase I and the transcription factors bound to the committed template. In this model Rrn3 would mediate an interaction between the mammalian Rrn3-polymerase I complex and SL1, the rDNA transcription factor that binds to the core promoter element of the rDNA. In the course of studying the role of Rrn3 in recruitment, we found that Rrn3 was in fact a DNA-binding protein. Analysis of the sequence of Rrn3 identified a domain with sequence similarity to the DNA binding domain of heat shock transcription factor 2. Randomization, or deletion, of the amino acids in this region in Rrn3, amino acids 382-400, abrogated its ability to bind DNA, indicating that this domain was an important contributor to DNA binding by Rrn3. Control experiments demonstrated that these mutant Rrn3 constructs were capable of interacting with both rpa43 and SL1, two other activities demonstrated to be essential for Rrn3 function. However, neither of these Rrn3 mutants was capable of functioning in transcription in vitro. Moreover, although wild-type human Rrn3 complemented a yeast rrn3-ts mutant, the DNA-binding site mutant did not. These results demonstrate that DNA binding by Rrn3 is essential for transcription by RNA polymerase I.

  5. Nuclear Factor-kappaB in Autoimmunity: Man and Mouse.

    Science.gov (United States)

    Miraghazadeh, Bahar; Cook, Matthew C

    2018-01-01

    NF-κB (nuclear factor-kappa B) is a transcription complex crucial for host defense mediated by innate and adaptive immunity, where canonical NF-κB signaling, mediated by nuclear translocation of RelA, c-Rel, and p50, is important for immune cell activation, differentiation, and survival. Non-canonical signaling mediated by nuclear translocation of p52 and RelB contributes to lymphocyte maturation and survival and is also crucial for lymphoid organogenesis. We outline NF-κB signaling and regulation, then summarize important molecular contributions of NF-κB to mechanisms of self-tolerance. We relate these mechanisms to autoimmune phenotypes described in what is now a substantial catalog of immune defects conferred by mutations in NF-κB pathways in mouse models. Finally, we describe Mendelian autoimmune syndromes arising from human NF-κB mutations, and speculate on implications for understanding sporadic autoimmune disease.

  6. Reduced skeletal muscle inhibitor of kappaB beta content is associated with insulin resistance in subjects with type 2 diabetes: reversal by exercise training.

    Science.gov (United States)

    Sriwijitkamol, Apiradee; Christ-Roberts, Christine; Berria, Rachele; Eagan, Phyllis; Pratipanawatr, Thongchai; DeFronzo, Ralph A; Mandarino, Lawrence J; Musi, Nicolas

    2006-03-01

    Skeletal muscle insulin resistance plays a key role in the pathogenesis of type 2 diabetes. It recently has been hypothesized that excessive activity of the inhibitor of kappaB (IkappaB)/nuclear factor kappaB (NFkappaB) inflammatory pathway is a mechanism underlying skeletal muscle insulin resistance. However, it is not known whether IkappaB/NFkappaB signaling in muscle from subjects with type 2 diabetes is abnormal. We studied IkappaB/NFkappaB signaling in vastus lateralis muscle from six subjects with type 2 diabetes and eight matched control subjects. Muscle from type 2 diabetic subjects was characterized by a 60% decrease in IkappaB beta protein abundance, an indicator of increased activation of the IkappaB/NFkappaB pathway. IkappaB beta abundance directly correlated with insulin-mediated glucose disposal (Rd) during a hyperinsulinemic (40 mU x m(-2) x min(-1))-euglycemic clamp (r = 0.63, P = 0.01), indicating that increased IkappaB/NFkappaB pathway activity is associated with muscle insulin resistance. We also investigated whether reversal of this abnormality could be a mechanism by which training improves insulin sensitivity. In control subjects, 8 weeks of aerobic exercise training caused a 50% increase in both IkappaB alpha and IkappaB beta protein. In subjects with type 2 diabetes, training increased IkappaB alpha and IkappaB beta protein to levels comparable with that of control subjects, and these increments were accompanied by a 40% decrease in tumor necrosis factor alpha muscle content and a 37% increase in insulin-stimulated glucose disposal. In summary, subjects with type 2 diabetes have reduced IkappaB protein abundance in muscle, suggesting excessive activity of the IkappaB/NFkappaB pathway. Moreover, this abnormality is reversed by exercise training.

  7. Effects of triptolide from Radix Tripterygium wilfordii (Leigongteng on cartilage cytokines and transcription factor