Photoaffinity labeling of rotavirus VP1 with 8-azido-ATP: identification of the viral RNA polymerase

Valenzuela, Sofía; Pizarro, Javiera; Sandino, Ana María; Vásquez, Mónica; Fernández, J; Hernández, Oscar; Patton, John T.; Spencer, Eugenio

doi:10.1128/jvi.65.7.3964-3967.1991

Cited by 74 publications

(21 citation statements)

References 26 publications

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“…Rotavirus VP1 has RNA-dependent RNA polymerase activity Valenzuela et al, 1991]. GenBank accession numbers of genes from KU, CAL-1, and Bristol which have been published previously and used in this analysis are as follows.…”

Section: Characterization Of B219 Vp1 and Vp4 Sequencesmentioning

confidence: 99%

Whole genomic characterization of a human rotavirus strain B219 belonging to a novel group of the genus rotavirus

Nagashima

Kobayashi

Ishino

et al. 2008

Journal of Medical Virology

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Novel rotavirus strains B219 and ADRV-N derived from adult diarrheal cases in Bangladesh and China, respectively, are considered to belong to a novel rotavirus group (species) distinct from groups A, B, and C, by genetic analysis of five viral genes encoding VP6, VP7, NSP1, NSP2, and NSP3. In this study, the nucleotide sequences of the remaining six B219 gene segments encoding VP1, VP2, VP3, VP4, NSP4, and NSP5 were determined. The nucleotide sequences of the group B human rotavirus VP1 and VP3 genes were also determined in order to compare the whole genome of B219 with those of group A, B, and C rotavirus genomes. The nucleotide and deduced amino acid sequences of all B219 gene segments showed considerable identity to the ADRV-N (strain J19) sequences (87.7-94.3% and 88.7-98.7%, respectively). In contrast, sequence identity to groups A-C rotavirus genes was less than 61%. However, functionally important domains and structural characteristics in VP1-VP4, NSP4, and NSP5, which are conserved in group A, B, or C rotaviruses, were also found in the deduced amino acid sequences of the B219 proteins. Hence, the basic structures of all B219 viral proteins are considered to be similar to those of the known rotavirus groups.

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Section: Characterization Of B219 Vp1 and Vp4 Sequencesmentioning

confidence: 99%

Whole genomic characterization of a human rotavirus strain B219 belonging to a novel group of the genus rotavirus

Nagashima

Kobayashi

Ishino

et al. 2008

Journal of Medical Virology

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“…The VP1 amino acid sequence contains the four major motifs commonly observed in RNA-dependent polymerases (Cohen et al, 1989;Poch et al, 1989;Bruenn, 1991;Suzuki et al, 1992), and some temperature-sensitive mutations mapping to the gene encoding VP1 render the virus unable to polymerize RNA (Chen et al, 1990). VP1 is specifically targeted by the nucleotide analog 8-azido-ATP (adenotn phosphate), which can ordinarily function as a substrate for RNA polymerization but becomes covalently cross-linked to VP1 upon ultraviolet irradiation, suggesting that VP1 is the protein that interacts with nucleotide substrates during RNA elongation (Valenzuela et al, 1991). The polymerase activity of VP1 in rotavirus has also been inferred from the observation that protein complexes formed from the coexpression of VP1 and the inner capsid protein VP2 are capable of using single-stranded mRNA as a template to generate dsRNA Patton et al, 1997).…”

Section: Components Of Endogenous Transcription Apparatusmentioning

confidence: 99%

“…All viral in vitro transcription systems in the family Reoviridae uniformly require the four nucleoside triphosphates (ATP, GTP, CTP, UTP) for the synthesis of RNA, and SAM is required for methylation of the cap at the 5' end of the transcripts. In rotavirus, some nucleotide analogs are able to substitute for the NTPs (Pizarro et al, 1991b;Valenzuela et al, 1991), but a form of ATP capable of being hydrolyzed to ADP must be included (Spencer and Garcia, 1984), presumably for helicase function. SAM is not explicitly required for RNA synthesis in vitro, but its presence enhances the rate of transcription in rotavirus (Spencer and Garcia, 1984), orbivirus (Van Dijk and Huismans, 1980), and cypovirus (Furuichi, 1981;Mertens and Payne, 1983), although apparently not in orthoreovirus (Shatkin, 1974).…”

Section: Mrna Precursorsmentioning

confidence: 99%

Mechanism of genome transcription in segmented dsRNA viruses

Lawton

Estes

Prasad

2000

Advances in Virus Research

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Genome transcription is a critical stage in the life cycle of a virus, as this is the process by which the viral genetic information is presented to the host cell protein synthesis machinery for the production of the viral proteins needed for genome replication and progeny virion assembly. Viruses with dsRNA genomes face a particular challenge in that host cells do not produce proteins which can transcribe from a dsRNA template. Therefore, dsRNA viruses contain all of the necessary enzymatic machinery to synthesize complete mRNA transcripts within the core without the need for disassembly. Indeed one of the more striking observations about genome transcription in dsRNA viruses is that this process occurs efficiently only when the transcriptionally competent particle is fully intact. This observation suggests that all of the components of the TCP, including the viral genome, the transcription enzymes, and the viral capsid, function together to produce and release mRNA transcripts and that each component has a specific and critical role to play in promoting the efficiency of this process. This review has examined the process of genome transcription in dsRNA viruses from the perspective of rotavirus as a model system. However, despite numerous architectural and organizational differences among the families of dsRNA viruses, numerous studies suggest that the basic mechanism of mRNA production may be similar in most, if not all, viruses having dsRNA genomes. Important functional similarities include (1) the presence of a capsid-bound RNA-dependent RNA polymerase, which produces single-stranded mRNA transcripts from the dsRNA genome and regenerates the dsRNA genome from single-stranded RNA templates; (2) in viruses infecting eukaryotic hosts, the presence of all the enzymatic activities needed to generate the 5' cap required by the eukaryotic translation machinery; (3) the high degree of structural order present in the packaged genome, suggesting the requirement for organization in the viral core; (4) the role of the innermost capsid protein as a scaffold on which the core components of the transcription apparatus are assembled; and (5) the release of nascent mRNA transcripts through channels at the icosahedral vertices. The process of genome transcription in dsRNA viruses will become better understood as structural studies progress to higher resolution and as more viruses become amenable to study using site-directed mutagenesis coupled with viral reconstitution to generate recombinant particles having precise functional and structural changes. Future studies will dissect important intermolecular interactions required for efficient mRNA synthesis and will shed further light on the reasons for which the viral core must be structurally intact in order for transcription to occur efficiently. Structural studies of the capping enzymes at atomic resolution will reveal how multiple enzyme activities reside within a single polypeptide and how they act in concert to synthesize the 5' cap on the end of each mature transcript. Pe...

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“…The outermost shell is made up of the glycoprotein, VP7, and the trypsin-activated spike protein, VP4, while the intermediate shell is formed from trimers of VP6 (39,48). The core of the virion includes the major inner shell protein, VP2 (20); the putative RNA-dependent RNA polymerase, VP1 (6,28,45); the putative guanylytransferase, VP3 (12,22,36); and the 11 genome segments. Cores surrounded by VP6 (double-shelled particles) have an associated transcriptase activity able to synthesize viral mRNA in vitro (1,7).…”

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confidence: 99%

cis-Acting signals that promote genome replication in rotavirus mRNA

Patton

Wentz

Xiaobo

et al. 1996

J Virol

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A previous study has shown that rotavirus cores have an associated replicase activity which can direct the synthesis of double-stranded RNA from viral mRNA in a cell-free system (. 68:7030-7039, 1994). To define the cis-acting signals in rotavirus mRNA that are important for RNA replication, gene 8 transcripts which contained internal and terminal deletions and chimeric transcripts which linked gene 8-specific 3-terminal sequences to the ends of nonviral sequences were generated. Analysis of these RNAs in the cell-free system led to the identification of a cis-acting signal in the gene 8 mRNA which is essential for RNA replication and two cis-acting signals which, while not essential for replication, serve to enhance the process. The sequence of the essential replication signal is located at the extreme 3 end of the gene 8 mRNA and, because of its highly conserved nature, is probably a common feature of all 11 viral mRNAs. By site-specific mutagenesis of the gene 8 mRNA, residues at positions ؊1, ؊2, ؊5, ؊6, and ؊7 of the 3 essential signal were found to be particularly important for promoting RNA replication. One of the cis-acting signals shown to enhance the replication in the cell-free system was located near the 5 end of the 3 untranslated region (UTR) of the gene 8 mRNA, while remarkably the other was located in the 5 UTR of the message. The existence of an enhancement signal in the 5 UTR raises the possibility that the 5 and 3 ends of the rotavirus mRNA may interact with each other and/or with the viral replicase during genome replication.

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Photoaffinity labeling of rotavirus VP1 with 8-azido-ATP: identification of the viral RNA polymerase

Cited by 74 publications

References 26 publications

Whole genomic characterization of a human rotavirus strain B219 belonging to a novel group of the genus rotavirus

Whole genomic characterization of a human rotavirus strain B219 belonging to a novel group of the genus rotavirus

Mechanism of genome transcription in segmented dsRNA viruses

cis-Acting signals that promote genome replication in rotavirus mRNA

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