scholarly journals The C, V and W proteins of Nipah virus inhibit minigenome replication

2008 ◽  
Vol 89 (5) ◽  
pp. 1300-1308 ◽  
Author(s):  
Katrina Sleeman ◽  
Bettina Bankamp ◽  
Kimberly B. Hummel ◽  
Michael K. Lo ◽  
William J. Bellini ◽  
...  
Keyword(s):  
Measles Virus ◽  
Sequence Similarity ◽  
Nipah Virus ◽  
Amino Acid Sequence Similarity ◽  
Dependent Manner ◽  
Highly Pathogenic ◽  
C Protein ◽  
P Gene ◽  
Dose Dependent ◽  
Cat Expression

Nipah virus (NiV) is a recently emergent, highly pathogenic, zoonotic paramyxovirus of the genus Henipavirus. Like the phosphoprotein (P) gene of other paramyxoviruses, the P gene of NiV is predicted to encode three additional proteins, C, V and W. When the C, V and W proteins of NiV were tested for their ability to inhibit expression of the chloramphenicol acetyltransferase (CAT) reporter gene in plasmid-based, minigenome replication assays, each protein inhibited CAT expression in a dose-dependent manner. The C, V and W proteins of NiV also inhibited expression of CAT from a measles virus (MV) minigenome, but not from a human parainfluenzavirus 3 (hPIV3) minigenome. Interestingly, the C and V proteins of MV, which have previously been shown to inhibit MV minigenome replication, also inhibited NiV minigenome replication; however, they were not able to inhibit hPIV3 minigenome replication. In contrast, the C protein of hPIV3 inhibited minigenome replication of hPIV3, NiV and MV. Although there is very limited amino acid sequence similarity between the C, V and W proteins within the paramyxoviruses, the heterotypic inhibition of replication suggests that these proteins may share functional properties.

scholarly journals Determination of the henipavirus phosphoprotein gene mRNA editing frequencies and detection of the C, V and W proteins of Nipah virus in virus-infected cells

2009 ◽  
Vol 90 (2) ◽  
pp. 398-404 ◽  
Author(s):  
Michael K. Lo ◽  
Brian H. Harcourt ◽  
Bruce A. Mungall ◽  
Azaibi Tamin ◽  
Mark E. Peeples ◽  
...  
Keyword(s):  
Nipah Virus ◽  
Hendra Virus ◽  
Mrna Editing ◽  
C Protein ◽  
Reading Frame ◽  
Frame Sequence ◽  
P Gene ◽  
Infected Cells ◽  
Phosphoprotein Gene

The henipaviruses, Nipah virus (NiV) and Hendra virus (HeV), are highly pathogenic zoonotic paramyxoviruses. Like many other paramyxoviruses, henipaviruses employ a process of co-transcriptional mRNA editing during transcription of the phosphoprotein (P) gene to generate additional mRNAs encoding the V and W proteins. The C protein is translated from the P mRNA, but in an alternate reading frame. Sequence analysis of multiple, cloned mRNAs showed that the mRNA editing frequencies of the P genes of the henipaviruses are higher than those reported for other paramyxoviruses. Antisera to synthetic peptides from the P, V, W and C proteins of NiV were generated to study their expression in infected cells. All proteins were detected in both infected cells and purified virions. In infected cells, the W protein was detected in the nucleus while P, V and C were found in the cytoplasm.

scholarly journals Mechanisms of Protein Kinase PKR-Mediated Amplification of Beta Interferon Induction by C Protein-Deficient Measles Virus

2009 ◽  
Vol 84 (1) ◽  
pp. 380-386 ◽  
Author(s):  
Christopher S. McAllister ◽  
Ann M. Toth ◽  
Ping Zhang ◽  
Patricia Devaux ◽  
Roberto Cattaneo ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Measles Virus ◽  
Mitogen Activated Protein Kinase ◽  
Potent Inducer ◽  
C Protein ◽  
P Gene ◽  
Mitogen Activated Protein ◽  
Order Of Magnitude ◽  
Infected Cells ◽  
Isogenic Mutants

ABSTRACT The measles virus P gene products V and C antagonize the host interferon (IFN) response, blocking both IFN signaling and production. Using Moraten vaccine strain-derived measles virus and isogenic mutants deficient for either V or C protein production (Vko and Cko, respectively), we observed that the Cko virus was a potent inducer of IFN-β, while induction by Vko virus was an order of magnitude lower than that by the Cko virus. The parental recombinant Moraten virus did not significantly induce IFN-β. The enhanced IFN-inducing capacity of the Cko virus correlated with an enhanced activation of IFN regulatory factor 3 (IRF-3), NF-κB, and ATF-2 in Cko-infected compared to Vko or parental virus-infected cells. Furthermore, protein kinase PKR and mitochondrial adapter IPS-1 were required for maximal Cko-mediated IFN-β induction, which correlated with the PKR-mediated enhancement of mitogen-activated protein kinase and NF-κB activation. Our results reveal multiple consequences of C protein expression and document an important function for PKR as an enhancer of IFN-β induction during measles virus infection.

Isolation of Bioactive Phenazine-1-Carboxamide from the Soil Bacterium Pantoea agglomerans and Study of Its Anticancer Potency on Different Cancer Cell Lines

2016 ◽  
Vol 99 (5) ◽  
pp. 1233-1239 ◽  
Author(s):  
Hayssam M Ali ◽  
Mohamed S El-Shikh ◽  
Mohamed Z M Salem ◽  
Muzaheed M
Keyword(s):  
Cell Lines ◽  
Cancer Cell ◽  
Messenger Rna ◽  
Cancer Cell Lines ◽  
Pantoea Agglomerans ◽  
Dependent Manner ◽  
Anticancer Effect ◽  
C Protein ◽  
Apoptosis Process ◽  
Dose Dependent

Abstract The study was designed to investigate the anticancer effect of phenazine-1-carboxamide (PCN) isolated from the bacterium Pantoea agglomerans naturally present in soil. PCN showed cytotoxicity in a dose-dependent manner, and inhibitory concentrations on the cancer cell lines A549, HeLa, and SW480 were between 32 and 40 μM. Significantly increased concentrations of lactate dehydrogenase were found with increasing concentrations of PCN, which resulted in increased destruction of the cancer cell membrane. A significantly increased p53 level was accompanied by the increased production of cytochrome c protein in all cancer cell lines studied. This condition in cells leads to the overexpression of caspase 3 and Bcl-2 family proteins. Upregulation and downregulation of proapoptotic and antiproapoptotic proteins were analyzed for their messenger RNA and protein expression. The activation of caspases and their cleavage compounds paves the way for the complete apoptosis process in cancer cells. We conclude that P. agglomerans–derived PCN acts as an effective anticancer drug or compound.

scholarly journals A Highly Attenuated Measles Virus Vaccine Strain Encodes a Fully Functional C Protein

2009 ◽  
Vol 83 (22) ◽  
pp. 11996-12001 ◽  
Author(s):  
Yuichiro Nakatsu ◽  
Makoto Takeda ◽  
Masaharu Iwasaki ◽  
Yusuke Yanagi
Keyword(s):  
Vaccine Strain ◽  
Measles Virus ◽  
Transcription Unit ◽  
C Protein ◽  
V Protein ◽  
P Gene ◽  
Its Gene ◽  
Overlapping Reading Frames ◽  
The Individual ◽  
Reading Frames

ABSTRACT The P, V, and C proteins of measles virus are encoded in overlapping reading frames of the P gene, which makes it difficult to analyze the functions of the individual proteins in the context of virus infection. We established a system to analyze the C protein independently from the P and V proteins by placing its gene in an additional transcription unit between the H and L genes. Analyses with this system indicated that a highly attenuated Edmonston lineage vaccine strain encodes a fully functional C protein, and the P and/or V protein is involved in the attenuated phenotype.

scholarly journals Nipah Virus C and W Proteins Contribute to Respiratory Disease in Ferrets

2016 ◽  
Vol 90 (14) ◽  
pp. 6326-6343 ◽  
Author(s):  
Benjamin A. Satterfield ◽  
Robert W. Cross ◽  
Karla A. Fenton ◽  
Viktoriya Borisevich ◽  
Krystle N. Agans ◽  
...  
Keyword(s):  
Respiratory Disease ◽  
Neurological Disease ◽  
Synergistic Effects ◽  
Nipah Virus ◽  
Small Animal ◽  
Neurological Impairment ◽  
C Protein ◽  
P Gene ◽  
Virus C ◽  
Viral Determinants

ABSTRACTNipah virus (NiV) is a highly lethal paramyxovirus that recently emerged as a causative agent of febrile encephalitis and severe respiratory disease in humans. The ferret model has emerged as the preferred small-animal model with which to study NiV disease, but much is still unknown about the viral determinants of NiV pathogenesis, including the contribution of the C protein in ferrets. Additionally, studies have yet to examine the synergistic effects of the various P gene products on pathogenesis in animal models. Using recombinant NiVs (rNiVs), we examine the sole contribution of the NiV C protein and the combined contributions of the C and W proteins in the ferret model of NiV pathogenesis. We show that an rNiV void of C expression resulted in 100% mortality, though with limited respiratory disease, like our previously reported rNiV void of W expression; this finding is in stark contrast to the attenuated phenotype observed in previous hamster studies utilizing rNiVs void of C expression. We also observed that an rNiV void of both C and W expression resulted in limited respiratory disease; however, there was severe neurological disease leading to 60% mortality, and the surviving ferrets demonstrated sequelae similar to those for human survivors of NiV encephalitis.IMPORTANCENipah virus (NiV) is a human pathogen capable of causing lethal respiratory and neurological disease. Many human survivors have long-lasting neurological impairment. Using a ferret model, this study demonstrated the roles of the NiV C and W proteins in pathogenesis, where lack of either the C or the W protein independently decreased the severity of clinical respiratory disease but did not decrease lethality. Abolishing both C and W expression, however, dramatically decreased the severity of respiratory disease and the level of destruction of splenic germinal centers. These ferrets still suffered severe neurological disease: 60% succumbed to disease, and the survivors experienced long-term neurological impairment, such as that seen in human survivors. This new ferret NiV C and W knockout model may allow, for the first time, the examination of interventions to prevent or mitigate the neurological damage and sequelae experienced by human survivors.

scholarly journals Stringent Requirement for the C Protein of Wild-Type Measles Virus for Growth both In Vitro and in Macaques

2005 ◽  
Vol 79 (12) ◽  
pp. 7838-7844 ◽  
Author(s):  
Kaoru Takeuchi ◽  
Makoto Takeda ◽  
Naoko Miyajima ◽  
Yasushi Ami ◽  
Noriyo Nagata ◽  
...  
Keyword(s):  
Cell Death ◽  
Cynomolgus Monkey ◽  
Neutralizing Antibodies ◽  
Measles Virus ◽  
Accessory Proteins ◽  
Wild Type ◽  
C Protein ◽  
Cynomolgus Monkeys ◽  
P Gene

ABSTRACT The P gene of measles virus (MV) encodes the P protein and three accessory proteins (C, V, and R). However, the role of these accessory proteins in the natural course of MV infection remains unclear. For this study, we generated a recombinant wild-type MV lacking the C protein, called wtMV(C−), by using a reverse genetics system (M. Takeda, K. Takeuchi, N. Miyajima, F. Kobune, Y. Ami, N. Nagata, Y. Suzaki, Y. Nagai, and M. Tashiro, J. Virol. 74:6643-6647). When 293 cells expressing the MV receptor SLAM (293/hSLAM) were infected with wtMV(C−) or parental wild-type MV (wtMV), the growth of wtMV(C−) was restricted, particularly during late stages. Enhanced green fluorescent protein-expressing wtMV(C−) consistently induced late-stage cell rounding and cell death in the presence of a fusion-inhibiting peptide, suggesting that the C protein can prevent cell death and is required for long-term MV infection. Neutralizing antibodies against alpha/beta interferon did not restore the growth restriction of wtMV(C−) in 293/hSLAM cells. When cynomolgus monkeys were infected with wtMV(C−) or wtMV, the number of MV-infected cells in the thymus was >1,000-fold smaller for wtMV(C−) than for wtMV. Immunohistochemical analyses showed strong expression of an MV antigen in the spleen, lymph nodes, tonsils, and larynx of a cynomolgus monkey infected with wtMV but dramatically reduced expression in the same tissues in a cynomolgus monkey infected with wtMV(C−). These data indicate that the MV C protein is necessary for efficient MV replication both in vitro and in cynomolgus monkeys.

scholarly journals Translational Inhibition and Increased Interferon Induction in Cells Infected with C Protein-Deficient Measles Virus

2006 ◽  
Vol 80 (23) ◽  
pp. 11861-11867 ◽  
Author(s):  
Yuichiro Nakatsu ◽  
Makoto Takeda ◽  
Shinji Ohno ◽  
Ritsuko Koga ◽  
Yusuke Yanagi
Keyword(s):  
Measles Virus ◽  
Translation Initiation Factor ◽  
Host Cells ◽  
Initiation Factor ◽  
Growth Defect ◽  
Ns1 Protein ◽  
C Protein ◽  
P Gene ◽  
Initiation Of Translation ◽  
Translational Inhibition

ABSTRACT In addition to the phosphoprotein, the P gene of measles virus (MV) also encodes the V and C proteins by an RNA editing process and by alternative initiation of translation in a different reading frame, respectively. Although the MV C protein is required for efficient MV replication in vivo and in some cultured cells, its exact functions in virus infection are currently unclear. Here, we report that a recombinant MV lacking the C protein (MVΔC) grew poorly in a human cell line possessing the intact interferon (IFN) pathway and that this growth defect was associated with reduced viral translation and genome replication. The translational inhibition was correlated with phosphorylation of the alpha subunit of eukaryotic translation initiation factor 2. Moreover, increased IFN induction was observed in MVΔC-infected cells. The NS1 protein of influenza virus, which binds to double-stranded RNA (dsRNA) and consequently inhibits IFN induction and dsRNA-dependent protein kinase activation, complemented the growth defect of MVΔC. These results indicate that the MV C protein inhibits IFN induction and modulates host antiviral responses, thereby ensuring MV growth in host cells.

scholarly journals Peripheral Administration of Nesfatin-1 Reduces Food Intake in Mice: The Leptin-Independent Mechanism

Endocrinology ◽  
2009 ◽  
Vol 150 (2) ◽  
pp. 662-671 ◽  
Author(s):  
H. Shimizu ◽  
S. Oh-I ◽  
K. Hashimoto ◽  
M. Nakata ◽  
S. Yamamoto ◽  
...  
Keyword(s):  
Food Intake ◽  
Arcuate Nucleus ◽  
Nucleus Tractus Solitarius ◽  
Sequence Similarity ◽  
Amino Acid Sequence Similarity ◽  
Dependent Manner ◽  
Peripheral Tissues ◽  
Cholinergic Pathway ◽  
Independent Mechanism ◽  
Active Segment

Nesfatin-1 is a novel satiety molecule in the hypothalamus and is also present in peripheral tissues. Here we sought to identify the active segment of nesfatin-1 and to determine the mechanisms of its action after peripheral administration in mice. Intraperitoneal injection of nesfatin-1 suppressed food intake in a dose-dependent manner. Nesfatin-1 has three distinct segments; we tested the effect of each segment on food intake. Injection of the midsegment decreased food intake under leptin-resistant conditions such as db/db mice and mice fed a high-fat diet. After injection of the midsegment, expression of c-Fos was significantly activated in the brainstem nucleus tractus solitarius (NTS) but not in the hypothalamic arcuate nucleus; the nicotinic cholinergic pathway to the NTS contributed to midsegment-induced anorexia. Midsegment injection significantly increased expression of proopiomelanocortin and cocaine- and amphetamine-regulated transcript genes in the NTS but not in the arcuate nucleus. Investigation of mutant midsegments demonstrated that a region with amino acid sequence similarity to the active site of agouti-related peptide was indispensable for anorexigenic induction. Our findings indicate that the midsegment of nesfatin-1 causes anorexia, possibly by activating POMC and CART neurons in the NTS via a leptin-independent mechanism after peripheral stimulation. Peripherally administered nesfatin-1 and its mid-segment suppress food intake in mice. The nicotinic cholinergic pathway to the nucleus tractus solitarius contributes to the anorexigenic action of the mid-segment.

scholarly journals Nonstructural C Protein Is Required for Efficient Measles Virus Replication in Human Peripheral Blood Cells

1999 ◽  
Vol 73 (2) ◽  
pp. 1695-1698 ◽  
Author(s):  
Carine Escoffier ◽  
Serge Manié ◽  
Séverine Vincent ◽  
Claude P. Muller ◽  
Martin Billeter ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Measles Virus ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Host Cells ◽  
Lymphoproliferative Response ◽  
Peripheral Blood Mononuclear ◽  
C Protein ◽  
P Gene

ABSTRACT The P gene of measles virus (MV) encodes the phosphoprotein, a component of the virus ribonucleoprotein complex, and two nonstructural proteins, C and V, with unknown functions. Growth of recombinant MV, defective in C or V expression, was explored in human peripheral blood mononuclear cells (PBMC). The production of infectious recombinant MV V− was comparable to that of parental MV tag in simian Vero fibroblasts and in PBMC. In contrast, MV C− progeny was strongly reduced in PBMC but not in Vero cells. Consistently, the expression of both hemagglutinin and fusion proteins, as well as that of nucleoprotein mRNA, was lower in MV C−-infected PBMC. Thus, efficient replication of MV in natural host cells requires the expression of the nonstructural C protein. The immunosuppression that accompanies MV infection is associated with a decrease in the in vitro lymphoproliferative response to mitogens. MV C− was as potent as MV tag or MV V− in inhibiting the phytohemagglutinin-induced proliferation of PBMC, indicating that neither the C protein nor the V protein is directly involved in this effect.

scholarly journals Measles Virus Phosphoprotein Gene Products: Conformational Flexibility of the P/V Protein Amino-Terminal Domain and C Protein Infectivity Factor Function

2004 ◽  
Vol 78 (21) ◽  
pp. 11632-11640 ◽  
Author(s):  
Patricia Devaux ◽  
Roberto Cattaneo
Keyword(s):  
Measles Virus ◽  
Cultured Cells ◽  
Conformational Flexibility ◽  
Particle Assembly ◽  
C Protein ◽  
Amino Terminal ◽  
Terminal Domain ◽  
P Gene ◽  
P Protein ◽  
Amino Terminal Domain

ABSTRACT The measles virus (MV) P gene codes for three proteins: P, an essential polymerase cofactor, and V and C, which have multiple functions but are not strictly required for viral propagation in cultured cells. V shares the amino-terminal domain with P but has a zinc-binding carboxyl-terminal domain, whereas C is translated from an overlapping reading frame. During replication, the P protein binds incoming monomeric nucleocapsid (N) proteins with its amino-terminal domain and positions them for assembly into the nascent ribonucleocapsid. The P protein amino-terminal domain is natively unfolded; to probe its conformational flexibility, we fused it to the green fluorescent protein (GFP), thereby also silencing C protein expression. A recombinant virus (MV-GFP/P) expressing hybrid GFP/P and GFP/V proteins in place of standard P and V proteins and not expressing the C protein was rescued and produced normal ratios of mono-, bi-, and tricistronic RNAs, but its replication was slower than that of the parental virus. Thus, the P protein retained nearly intact polymerase cofactor function, even with a large domain added to its amino terminus. Having noted that titers of cell-associated and especially released MV-GFP/P were reduced and knowing that the C protein of the related Sendai virus has particle assembly and infectivity factor functions, we produced an MV-GFP/P derivative expressing C. Intracellular titers of this virus were almost completely restored, and those of released virus were partially restored. Thus, the MV C protein is an infectivity factor.

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