The group of Negative-Stranded RNA Viruses (NSVs) includes many human pathogens, like the influenza, measles, mumps, respiratory syncytial or Ebola viruses, which produce frequent epidemics of disease and occasional, high mortality outbreaks by transmission from animal reservoirs. The genome of NSVs consists of one to several single-stranded, negative-polarity RNA molecules that are always assembled into mega Dalton-sized complexes by association to many nucleoprotein monomers. These RNA-protein complexes or ribonucleoproteins function as templates for transcription and replication by action of the viral RNA polymerase and accessory proteins. Here we review our knowledge on these large RNA-synthesis machines, including the structure of their components, the interactions among them and their enzymatic activities, and we discuss models showing how they perform the virus transcription and replication programmes. - Highlights: • Overall organisation of NSV RNA synthesis machines. • Structure and ...
TY - JOUR. T1 - Detection of negative-stranded hepatitis C virus RNA using a novel strand-specific reverse transcription-polymerase chain reaction. AU - Mizutani, Tetsuya. AU - Ikeda, Masanori. AU - Saito, Satoru. AU - Sugiyama, Kazuo. AU - Shimotohno, Kunitada. AU - Kato, Nobuyuki. PY - 1998/2/1. Y1 - 1998/2/1. N2 - We developed a novel single-tube reverse transcription-polymerase chain reaction (RT-PCR) for the specific detection of negative-stranded hepatitis C virus (HCV) RNA. By using in vitro synthesized positive- and negative-stranded HCV RNAs, it was demonstrated that as few as 50 copies of negative-stranded HCV RNA could be specifically detected with a set of primers that amplify a 232-base pair sequence unique to the 5-non-coding region of HCV RNA, while 108 copies of positive-stranded HCV RNA were not detected. In addition, we demonstrated that this method allows the detection as few as 100 copies of negative-stranded HCV RNA even with the coexistence of a 100-fold excess of ...
387440791 - EP 0832191 A4 2000-11-15 - RECOMBINANT VIRAL NUCLEIC ACIDS - [origin: WO9640867A1] The present invention relates to a recombinant viral nucleic acid selected from a (+) sense, single stranded RNA virus possessing a native subgenomic promoter encoding for a first viral subgenomic promoter, a nucleic acid sequence that codes for a viral coat protein whose transcription is regulated by the first viral subgenomic promoter, a second viral subgenomic promoter and a second nucleic acid sequence whose transcription is regulated by the second viral subgenomic promoter. The first and second viral subgenomic promoters of the recombinant viral nucleic acid do not have homologous sequences relative to each other. The recombinant viral nucleic acid provides the particular advantage that it systematically transcribes the second nucleic acid in the host. Host organisms encompassed by the present invention include procaryotes and eucaryotes, particularly animals and plants. The present invention also relates
Two copies of unspliced human immunodeficiency virus (HIV)-1 genomic RNA (gRNA) are preferentially selected for packaging by the group-specific antigen (Gag) polyprotein into progeny virions as a dimer during the late stages of the viral lifecycle. Elucidating the RNA features responsible for selective recognition of the full-length gRNA in the presence of an abundance of other cellular RNAs and spliced viral RNAs remains an area of intense research. The recent nuclear magnetic resonance (NMR) structure by Keane et al. [1] expands upon previous efforts to determine the conformation of the HIV-1 RNA packaging signal. The data support a secondary structure wherein sequences that constitute the major splice donor site are sequestered through base pairing, and a tertiary structure that adopts a tandem 3-way junction motif that exposes the dimerization initiation site and unpaired guanosines for specific recognition by Gag. While it remains to be established whether this structure is conserved in the context
Polivirüsün hücresel yaşam döngüsü (1) CD155 reseptörüne bağlanmasıyla başlar. Virüs endositozla alınır, ve viral RNA serbest kalır (2). Translation of the viral RNA occurs by an IRES-mediated mechanism (3). The polyprotein is cleaved, yielding mature viral proteins (4). The positive-sense RNA serves as template for complementary negative-strand synthesis, producing double-stranded replicative form (RF) RNA(5). Many positive strand RNA copies are produced from the single negative strand (6). The newly synthesized positive-sense RNA molecules can serve as templates for translation of more viral proteins (7) or can be enclosed in a capsid (8), which ultimately generates progeny virions. Lysis of the infected cell results in release of infectious progeny virions (9).[2] ...
This review is centered on the major strategies used by plant RNA viruses to produce the proteins required for virus multiplication. The strategies at the level of transcription presented here are synthesis of mRNA or subgenomic RNAs from viral RNA templates, and cap-snatching. At the level of translation, several strategies have been evolved by viruses at the steps of initiation, elongation and termination. At the initiation step, the classical scanning mode is the most frequent strategy employed by viruses; however in a vast number of cases, leaky scanning of the initiation complex allows expression of more than one protein from the same RNA sequence. During elongation, frameshift allows the formation of two proteins differing in their carboxy terminus. At the termination step, suppression of termination produces a protein with an elongated carboxy terminus. The last strategy that will be described is co- and/or post-translational cleavage of a polyprotein precursor by virally encoded ...
Upon entry, the host cell senses an invasion. Recent evidence suggests that structured viral RNAs can act as Pathogen Associated Molecular Patterns (PAMPs) that are recognized by host Pattern Recognition Receptors (PRR) to activate cell signaling. An immediate goal of the laboratory is to understand how specific viral RNA-protein interactions influence the viral life cycle and the host immune response. The triphosphate group found at the 5 end of some viral RNA transcripts (5 3P) has been described recently as an important determinant of "self versus non-self" that allows cells to distinguish between viral and cellular RNAs. Our results suggest that the 5 3P cannot be the only determinant because some RNAs with a 5 3P are potent activators, while others cause no activation of innate immune signaling. We have identified a non-structured region in the hepatitis C virus (HCV) 3 untranslated region RNA that activates innate immune signaling by interacting with the RNA helicase RIG-I. We ...
The extra length that dimer RNA provides is critical in encouraging PKR to pair up and function properly. "The length needed for one PKR to bind to RNA is fifteen base pairs," said Philip Bevilacqua, professor of chemistry, Penn State, one of the lead scientists on the project along with James Cole, associate professor, University of Connecticut. "To get two PKRs to bind and dimerize, you need an RNA strand that is twice as long." Coles laboratory provided evidence of dimerization of RNA and PKR. In their experiments at Penn State, the scientists found the dimer RNA activated PKR from 9 to 118 times more than the single strand RNA, depending on the RNA type. TAR RNA dimerization activated the most PKR when the TAR did not exhibit structural defects. The researchers report their findings in a recent issue of the Journal of Molecular Biology. "Adding these defects decreases the number of places where PKR can bind to the RNA," Heinicke explained. RNAs that showed the greatest degree of symmetry ...
The genomes of RNA viruses often contain RNA structures that are crucial for translation and RNA replication and may play additional, uncharacterized roles during the viral replication cycle. RNA structure with single-nucleotide resolution. In combination with orthogonal evolutionary analyses, we uncover several conserved RNA structures in the open reading frame of the viral genome. The…
Id like to determine viral RNA level changes in virus producing cell culture transfected with as-DNA. Can anybody provide me with a protocol and anything to be noted in the operation? Thanks in advance.. ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Patients are stratified by screening plasma viral RNA results (50,000 copies/ml or below vs above 50,000 copies/ml) and randomized to 1 of 2 treatment arms. Group 1 receives IDV 3 times daily plus d4T/3TC twice daily. Group 2 receives IDV/NFV/d4T/3TC twice daily. Patients remain on study medications for 24 weeks and are seen at the clinic once every 4 weeks after entering the study. At each clinic visit, blood samples are taken to evaluate CD4 cell count and plasma HIV RNA levels ...
Dear All, I am looking for a reliable method for the quantitation of in vitro transcribed RNA. If its quick and cheap alls the better. Also does anyone else have problems with the Ambion capped RNA making kit, Ithink they call it the mMESSAGE mMACHINE. We seem t get such variable results in term of yield its untrue, even when we make RNA from the same sample of linearised DNA (But on different days) Robert R. Woodward Email rw200 at cus.cam.ac.uk d ...
The one-step RT-ddPCR kit for probes, introduced by Bio-Rad Laboratories, Inc., provides researchers with the ability to measure target RNA molecules with precision and sensitivity for applications such as gene expression analysis, miRNA analysis, and viral load quantitation.
... The genome of HIV is diploid, composed of 2 identical single stranded positive sense RNA copies. In association with viral RNA is the reverse transcriptase enzyme which is the characteristic
... The genome of HIV is diploid, composed of 2 identical single stranded positive sense RNA copies. In association with viral RNA is the reverse transcriptase enzyme which is the characteristic
[The episode starts with tons of virus organisms on Gumballs fur, then one of them stands on a hill-like lump of fur] Virus: Brothers, weve mutated many times over for this moment, but now we are ready. Today, we take this body; tomorrow, the REST OF THE WORLD! [The virus army starts cheering...
STDcheck.com offers the only HIV RNA early detection test that can give results as soon as 9 to 11 days post exposure to HIV. Know your HIV status sooner!
Consequently, despite the very simple reality that these RNA species are labeled as unstable, processing of many CUTs seems for being somewhat slow. domyhomeworkfor.me DNA can be a form of nucleic acid and it truly is composed of billions of nucleotides and a few certain amino acids. These organisms reside in
Tusq X Plus-ன் பயன்பாடுகள், மருந்தளவு, பக்க விளைவுகள், நன்மைகள், தொடர்புகள் மற்றும் எச்சரிக்கைகள் ஆகியவற்றை கண்டுபிடியுங்கள்.
Summary of Facts and Submissions. I. European patent No. 0 846 181 with the title cDNA corresponding to the antigenome of nonsegmented negative strand RNA viruses, and process for the production of such viruses encoding additional antigenically active proteins was granted on European patent application No. 96928446.2 (published as WO 97/06270). The patent was granted with 21 claims.. II. Claim 1 of the patent as granted read as follows:. 1. A method for the production of an infectious non-segmented negative-strand RNA virus of the family Paramyxoviridae comprising. (a) introducing a cDNA molecule contained in a plasmid, wherein said cDNA molecule comprises the entire (+)-strand sequence of said negative- strand RNA virus operatively linked to an expression control sequence, which allows the synthesis of anti-genomic RNA transcripts bearing the authentic 3 -termini, and wherein said cDNA molecule consists of an integral multiple of six nucleotides, into a helper cell expressing an ...
A positive-sense single-stranded RNA virus (or (+)ssRNA virus) is a virus that uses positive sense, single-stranded RNA as its genetic material. Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA. The positive-sense viral RNA genome can also serve as messenger RNA and can be translated into protein in the host cell. Positive-sense ssRNA viruses belong to Group IV in the Baltimore classification. Positive-sense RNA viruses account for a large fraction of known viruses, including many pathogens such as the hepatitis C virus, West Nile virus, dengue virus, and SARS and MERS coronaviruses, as well as less clinically serious pathogens such as the rhinoviruses that cause the common cold. Positive-sense ssRNA viruses have genetic material that can function both as a genome and as messenger RNA; it can be directly translated into protein in the host cell by host ribosomes. The first proteins to be expressed after infection serve genome ...
In this study we developed a novel highly adapted HCV replicon that harbors two synergistic mutations in NS3 and one in NS5A. The ECF of this RNA was ∼5 × 105 CFU per μg of RNA, which is ∼20-fold higher than that of the best-adapted replicon we described recently (29). By analyzing this and several other HCV RNAs that differed with respect to their levels of cell culture adaptation, we found a clear correlation between the ECF and RNA replication as determined by two different transient-transfection assays. These results demonstrate that cell culture-adaptive mutations increase RNA replication. They also provide an explanation of how adaptive replicons are generated. As shown with the parental replicon carrying the luciferase gene, this nonadapted RNA replicated only transiently and at a low level in transfected cells. During this time, mutations must have been generated by the viral RNA polymerase that in a few instances were adaptive. By increasing the level of RNA replication, cells ...
A negative-sense single-stranded RNA virus (or (-)ssRNA virus) is a virus that uses negative sense, single-stranded RNA as its genetic material. Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA. The negative viral RNA is complementary to the mRNA and must be converted to a positive RNA by RNA polymerase before translation. Therefore, the purified RNA of a negative sense virus is not infectious by itself, as it needs to be converted to a positive sense RNA for replication. These viruses belong to Group V on the Baltimore classification. In addition, negative-sense single-stranded RNA viruses have complex genomic sequences, cell cycles, and replication habits that use various protein complexes to arrange in specific conformations and carry out necessary processes for survival and reproduction of their genomic sequences. The complexity of negative-sense single-stranded RNA viruses carries into its ability to suppress the innate immune ...
TY - JOUR. T1 - Importance of the positive-strand RNA secondary structure of a murine coronavirus defective interfering RNA internal replication signal in positive-strand RNA synthesis. AU - Repass, John F.. AU - Makino, Shinji. PY - 1998/10. Y1 - 1998/10. N2 - The RNA elements that are required for replication of defective interfering (DI) RNA of the JHM strain of mouse hepatitis virus (MHV) consist of three discontinuous genomic regions: about 0.46 to 0.47 kb from both terminal sequences and an internal 58-nucleotide (nt)-long sequence (58-nt region) present at about 0.9 kb from the 5 end of the DI genome. The internal region is important for positive-strand DI RNA synthesis (Y. N. Kim and S. Makino, J. Virol. 69:4963-4971, 1995). We further characterized the 58-nt region in the present study and obtained the following results. (i) The positive-strand RNA structure in solution was comparable with that predicted by computer modeling. (ii) Positive-strand RNA secondary structure, but not ...
Both genomic and subgenomic replicative intermediates (RIs) and replicative-form (RF) structures were found in 17CL1 mouse cells that had been infected with the A59 strain of mouse hepatitis virus (MHV), a prototypic coronavirus. Seven species of RNase-resistant RF RNAs, whose sizes were consistent with the fact that each was derived from an RI that was engaged in the synthesis of one of the seven MHV positive-strand RNAs, were produced by treatment with RNase A. Because the radiolabeling of the seven RF RNAs was proportional to that of the corresponding seven positive-strand RNAs, the relative rate of synthesis of each of the MHV positive-strand RNAs may be controlled by the relative number of each of the size classes of RIs that are produced. In contrast to alphavirus, which produced its subgenome-length RF RNAs from genome-length RIs, MHV RF RNAs were derived from genome- and subgenome-length RIs. Only the three largest MHV RF RNAs (RFI, RFII, and RFIII) were derived from the RIs that ...
Poliovirus RNA replicates in membrane-associated replication complexes in the cytoplasm of infected cells. By using a reversible inhibitor of poliovirus RNA replication, it is possible to synchronize viral RNA replication. The processing of the viral polyprotein results in the formation of the individual viral proteins along with stable intermediates in the processing pathway. To expand the utility of the in vitro complementation assay, experiments were designed to determine if all of the viral replication proteins could be provided in trans to support the replication of mutant RNA templates. The authors engineered two transcript RNAs (DJB2 and DJB15) that contained large out-of-frame deletions in the polyprotein coding sequence. The results to date using the in vitro complementation assay indicate that the 5 cloverleaf, the 3 nontranslated region (NTR), and the poly(A) tail are the minimum sequences required for negative-strand synthesis. Previous studies have shown that the 5 cloverleaf plays an
Figure 2 shows the genome organization of GRV; those of other umbraviruses are very similar. For each RNA, there is at the 5′ end a very short non-coding region preceding ORF1, which encodes a putative product of 31-37 kDa. ORF2, which slightly overlaps the end of ORF1, could encode a product of 63-65 kDa but lacks an AUG initiation codon near its 5′ end. However, immediately before the stop codon of ORF1 there is a 7 nt sequence that is associated with frameshifting in several plant and animal viruses, and it seems probable that ORF1 and ORF2 are translated as a single polypeptide of 94-98 kDa by a mechanism involving a −1 frameshift. The predicted product contains, in the ORF2 region, sequence motifs characteristic of viral RdRp. A short untranslated region separates ORF2 from ORF3 and ORF4, which overlap each other almost completely in different reading frames and each yield a putative product of 26-29 kDa. The ORF4 product contains sequences characteristic of plant virus MPs. The ORF3 ...
TY - JOUR. T1 - Molecular cloning of full-length HIV-1 genomes directly from plasma viral RNA. AU - Fang, Guowei. AU - Weiser, Barbara. AU - Visosky, Aloise A.. AU - Townsend, Laura. AU - Burger, Harold. PY - 1996. Y1 - 1996. N2 - Human immunodeficiency virus type 1 (HIV-1) in plasma reflects the replicating virus population at any point in time in vivo. Studies of the relationship of the complete HIV-1 genome to pathogenesis therefore need to focus on plasma virions. Since dual infections and recombination can occur in vivo, cloning an intact plasma virus genome as a single full-length molecule is desirable. For these reasons, we developed an efficient method to clone full-length HIV-1 genomes directly from plasma viral RNA. This method used reverse transcription and long polymerase chain reaction (PCR) amplification. Virion-associated RNA was isolated from plasma samples and then reverse- transcribed to make cDNA for PCR amplification. Two different strategies were employed to amplify the ...
Shop RNA replication protein ELISA Kit, Recombinant Protein and RNA replication protein Antibody at MyBioSource. Custom ELISA Kit, Recombinant Protein and Antibody are available.
Hepatitis C trojan (HCV) is an enveloped, positive strand RNA computer virus of about 9. attributable to inherently different properties of low density particles, to association of these particles with factors stimulating fusion, or to co-floatation of factors enhancing fusion activity in genus of the Flaviviridae family (1). Based on sequence comparison, patient isolates are classified into seven genotypes, differing in their nucleotide sequence by 30C35% (2C5). The two viral surface proteins, E1 (residues 192C383) and E2 (residues 384C746), are processed by transmission peptidases of the endoplasmic reticulum from a 3,000-amino acid-long polyprotein encoded by the HCV genome (examined in Ref. 2). The E1 (31 kDa) and E2 (70 kDa) proteins are glycosylated in their large amino-terminal ectodomains (6) and are anchored in the viral membrane by their carboxyl-terminal transmembrane domains. E1 and E2 form a heterodimer stabilized by noncovalent interactions. This oligomer is usually thought to be ...
Early biochemical experiments established that the minimal RNA synthesis machinery of NNS RNA viruses comprises the N encased genomic RNA associated with the viral polymerase, an L-P complex (Emerson and Yu, 1975; Mellon and Emerson, 1978). The atomic structure of N‐RNA complexes from VSV and rabies virus provided evidence that the RNA must somehow be dissociated from N for copying by the polymerase (Albertini et al, 2006; Green et al, 2006). The co‐crystal structure of the PCTD of VSV with the N‐RNA complex led to a model in which P brings L to the RNA template by binding directly between N molecules, and this interaction is perhaps also required to keep L associated with the N‐RNA during copying (Green and Luo, 2009). By now providing the first direct evidence that L can actually use RNA in the absence of the N and P, we have defined the minimal RNA synthesis components as L and RNA. We conclude that while N and P play important roles in viral RNA synthesis they are not essential for ...
Hepatitis C virus (HCV) is a single-stranded plus-sense RNA virus that is transmitted by blood-to-blood contact, and infects the human liver. HCV has a unique dependence on the liver-specific microRNA miR-122, where miR-122 binds the 5´ un-translated region of the viral RNA at two tandem sites and increases viral RNA abundance. The mechanisms of augmentation are not yet fully understood, but the interaction is known to stabilize the viral RNA, increase translation from the viral internal ribosomal entry site (IRES), and result in increased viral yield. In an attempt to create a small animal model for HCV, we added miR-122 to mouse cell lines previously thought non-permissive to HCV, which rendered these cells permissive to the virus, additionally showing that miR-122 is one of the major determinants of HCV hepatotropism. We found that some wild-type and knockout mouse cell lines - NCoA6 and PKR knockout embryonic fibroblasts - could be rendered permissive to transient HCV sub-genomic, but not ...
Hepatitis C Virus Translation Preferentially Depends on Active RNA Replication. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
The HCV replication complex. After clathrin-mediated endocytosis, fusion of HCV with cellular membranes, and uncoating the viral nucleocapsid, the single-stranded positive-sense RNA genome of the virus of approximately 9600 nucleotides is released into the cytoplasm to serve as a messenger RNA for the HCV polyprotein precursor. The HCV genome contains a single large open reading frame encoding for a polyprotein of approximately 3100 amino acids. The translated section of the HCV genome is flanked by the strongly conserved HCV 3′ and 5′ untranslated regions (UTR). The 5′ UTR is comprised of four highly structured domains forming the internal ribosome entry site (IRES), which is a virus-specific structure to initiate HCV mRNA translation. From the initially translated polyprotein, the structural HCV protein core (C) and envelope 1 and 2 (E1, E2); p7; and the six nonstructural HCV proteins NS2, NS3, NS4A, NS4B, NS5A and NS5B, are processed by both viral and host proteases. The core protein ...
The overall goal of our research is to understand the structure and function of RNA molecules. Most of our early work focused on ribosomal RNA (rRNA), characterizing the role of the RNA in protein synthesis (Vila et al 1994, Thompson et al 2001). More recently, we have turned our attention to understanding the structure and function of viral RNA molecules, particularly enteroviral genomic RNA. We have conducted studies to learn the structure of the internal ribosome entry site (IRES) RNA found in picornaviruses (Kim et al., 2005, Bailey and Tapprich 2007) and we have determined virulence determinants in picornal genomic RNA (Prusa et al. 2014). In our initial studies we have used chemical modification and primer extension to deduce the structure of the IRES elements in coxsackievirus B3. This analysis has been completed for virulent wild type viruses, attenuated mutant viruses and avirulent viruses. We have shown localized structural changes in the IRES RNA that correlate with virulence. These ...
Coronaviruses are positive-strand RNA viruses that are important infectious agents of both animals and humans. A common feature among positive-strand RNA viruses is their assembly of replication-transcription complexes in association with cytoplasmic membranes. Upon infection, coronaviruses extensively rearrange cellular membranes into organelle-like replicative structures that consist of double-membrane vesicles and convoluted membranes to which the nonstructural proteins involved in RNA synthesis localize. Double-stranded RNA, presumably functioning as replicative intermediate during viral RNA synthesis, has been detected at the double-membrane vesicle interior. Recent studies have provided new insights into the assembly and functioning of the coronavirus replicative structures. This review will summarize the current knowledge on the biogenesis of the replicative structures, the membrane anchoring of the replication-transcription complexes, and the location of viral RNA synthesis, with particular
Once transcribed, the nascent full-length RNA of HIV-1 must travel to the appropriate host cell sites to be translated or to find a partner RNA for copackaging to form newly generated viruses. In this report, we sought to delineate the location where HIV-1 RNA initiates dimerization and the influence of the RNA transport pathway used by the virus on downstream events essential to viral replication. Using a cell-fusion-dependent recombination assay, we demonstrate that the two RNAs destined for copackaging into the same virion select each other mostly within the cytoplasm. Moreover, by manipulating the RNA export element in the viral genome, we show that the export pathway taken is important for the ability of RNA molecules derived from two viruses to interact and be copackaged. These results further illustrate that at the point of dimerization the two main cellular export pathways are partially distinct. Lastly, by providing Gag in trans, we have demonstrated that Gag is able to package RNA from either
This observation argues that RNPs are not randomly incorporated into virions, and is consistent with the presence of specific signals in each RNA segment that enable the RNPs to be packaged as a complete set. The mechanisms by which these signals are recognized, and how they ensure incorporation of one copy of each RNA segment into the particle, are not known.. There is clear evidence for a selective mechanism during the packaging of the bacteriophage ψ6 genome. Viral particles contain one copy each of a S, M, and L dsRNA segment. All particles contain a complete complement of genome segments, as indicated by the fact that every virus particle is infectious. Only the S RNA segment can enter newly formed particles; once that segment is packaged, then the M RNA can enter. The L RNA can only enter particles that contain both the S and M segments. Precise packaging is therefore the result of a serial dependence of packaging of the RNA segments.. Muramoto, Y., Takada, A., Fujii, K., Noda, T., ...
Viral RNA-dependent RNA Polymerase Assay. The Viral RNA-dependent RNA Polymerase Assay is developed using a RNA polymerase in the Flaviviridae,. a family of positive, single-stranded, enveloped RNA viruses. The assay is based on measurement of the. RNA molecules synthesized by the RNA polymerase using RNA as a template in the presence of NTPs.. The assay can be performed in a 384-well or 96-well plate format for tests of theenzyme activities of RNA. polymerases in the Flaviviridae family and high throughput screening of inhibitors. ...
My group uses X-ray crystallography as a central technique to study the structure-function relationships of complexes involving RNA of various kinds in eukaryotic cells. This includes the transcription/replication machinery of segmented negative strand RNA viruses (e.g. influenza), complexes involved in sorting of Pol II transcripts into their appropriate processing pathways and innate immune system pattern recognition receptors, notably the response to viral RNA via Rig-I like helicases.. Keywords: Protein-RNA recognition / aminoacyl tRNA synthetases / RNA metabolism / virus structure / influenza virus polymerase / innate immunity / Rig-I like helicases / X-ray crystallography. Subject area(s): Microbiology, Virology & Pathogens , RNA , Structural Biology & Biophysics. ...
role of rna-protein interactions in the internal initiation of translation of plus-strand rna viruses : a novel target for antiviral therapeutics
Although changing therapies is a common strategy in the treatment of HIV disease, guidelines are needed to help clinicians and patients decide when a change in antiretroviral therapy is indicated. The technology of measuring HIV RNA in plasma has been suggested as a tool for monitoring clinical drug efficacy. However, uncertainty remains about whether aggressive antiretroviral treatment to lower HIV RNA and maintain low levels for as long as possible will confer clinical benefit in comparison with management based on monitoring CD4 counts and HIV-related symptoms.. Patients are randomized to a decision making strategy for initiating or changing therapy based on current clinical practice alone vs. decision making based on plasma HIV RNA quantitation in addition to current clinical practice in patients with ,= 300 CD4+ cells/mm3. All patients in the RNA arm as well as a subset (n = 183) of those in the CCP arm will have a plasma HIV RNA quantitation drawn every 4 months. The results of these ...
The bunyavirus genome is monomeric and consists of three segments of linear negative-sense (or ambisense, depending on the genus) RNA. The terminal sequences of each segment are base-paired. Because of this, the RNAs form non-covalently closed circles. The nucleotide sequences at the 3-terminus and the 5-terminus are complimentary, forming panhandle structures. The 5-terminus is not capped. The complete genome is 10500-22700 nucleotides long. The three segments of the genome are labeled L, M, and S. The L segment is 6300-12000 nucleotides long and encodes the viral RNA polymerase. The M segment is 3500-6000 nucleotides long and encodes two glycoproteins as a single gene product that is usually co-translationally cleaved. The S segments is 1000-2200 nucleotides long and encodes the coat protein. (sources: Descriptions of Plant Viruses, ICTVdB) ...
Genome RNA replication of all (+)RNA viruses takes place in close association with rearranged intracellular membranes. We are only beginning to understand the biogenesis and ultrastructure of these virus-induced membrane structures. In collaboration with the virology groups of LUMC (Prof. Dr. Eric Snijder) and the University of Utrecht (Prof. Dr. Frank van Kuppeveld), EM and tomography approaches will be used to gain more insight into the architecture of the rearranged membranes, the localization of the viral replication enzymes, and the localization of host factors that are hijacked by picornavirus to facilitate replication of their RNA genome.. Host institute ...
Once the (-) strand influenza viral RNAs enter the nucleus, they serve as templates for the synthesis of mRNAs. These molecules are then transported back to the cytoplasm, where they direct the synthesis of viral proteins. However, the mRNAs are not complete copies of the viral (-) strand RNAs - they are missing sequen
The multiscale model of hepatitis C virus (HCV) dynamics, which includes intracellular viral RNA (vRNA) replication, has been formulated in recent years in order to provide a new conceptual framework for understanding the mechanism of action of a variety of agents for the treatment of HCV. We present a robust and efficient numerical method that belongs to the family of adaptive stepsize methods and is implicit, a Rosenbrock type method that is highly suited to solve this problem. We provide a Graphical User Interface that applies this method and is useful for simulating viral dynamics during treatment with anti-HCV agents that act against HCV on the molecular level.
Recent studies have shown that replication of hepatitis C virus (HCV) is dependent on miR-122 expression.[20] miR-122 regulates HCV by binding directly to two adjacent sites close to the 5 end of HCV RNA.[21] Although these experiments were conducted using genotype 1a and 1b HCV RNA, the miR-122 binding sites are highly conserved across different genotypes, and miR-122 is also required for replication of infectious type 2a HCV.[22] As miRNAs generally function to repress gene expression by binding to 3UTR sites, this positive regulation of viral replication via a 5UTR represents a novel function for miR-122. The mechanism of regulation is not yet clear. miR-122 stimulates translation of HCV RNA, but not to a sufficient extent to explain its effects on viral replication, indicating that a second stage of the viral replication cycle must also be regulated.[23][24] HCV RNA synthesis is not affected by miR-122, suggesting that regulation of other processes such as RNA stability may occur.[25][26] ...
Hiv rna pcr test - What is the window period for p42 antigen/ antibody dual 4th gen HIV test? And the window period for HIV RNA PCR test? When can it be conclusive? See below. Please consult this site for a detailed answer. Nucleic acid tests are conclusive about a month after acquiring infection. Http://www. Sfaf. Org/hiv-info/testing/hiv-test-window-periods. Html
TheBody.com fills you in on the topic, how accurate is the hiv rna test, with a wealth of fact sheets, expert advice, community perspective, the latest news/research, and much more.