During replication of the viral genome, RdRp synthesizes a positive-sense antigenome that it uses as a template to create genomic negative-sense RNA. (wikipedia.org)
Uncoating, and release of the viral genomic RNA into the cytoplasm. (expasy.org)
Viral genomic RNA has a viral protein (VPg) at its 5' end instead of a methylated nucleotide cap structure. (expasy.org)
Upon endosomal acidification, the capsid releases VP4 that opens a pore in the host endosomal membrane and the viral genomic RNA penetrates into the host cell cytoplasm. (expasy.org)
New genomic RNA is believed to be packaged into preassembled procapsids . (expasy.org)
After translation of their mRNA-sense genomic RNA(s), the viral RNA and the viral replication proteins are recruited to the site of viral replication in membranous compartments. (prolekarniky.cz)
The single genomic RNA codes for two replication proteins, p33 and p92 pol , which are sufficient to support TBSV replicon (rep)RNA replication in yeast ( Saccharomyces cerevisiae ) model host [13] , [14] . (prolekarniky.cz)
Polymerase3
They have genomes that act as complementary strands from which messenger RNA (mRNA) is synthesized by the viral enzyme RNA-dependent RNA polymerase (RdRp). (wikipedia.org)
Their genomes are negative sense, meaning that messenger RNA (mRNA) can be synthesized directly from the genome by the viral enzyme RNA-dependent RNA polymerase (RdRp), also called RNA replicase, which is encoded by all −ssRNA viruses. (wikipedia.org)
In this study we expressed plant DCL4 in Saccharomyces cerevisiae , an RNAi-depleted organism, in which we could highlight the role of dicing as neither Argonautes nor RNA-dependent RNA polymerase is present. (biomedcentral.com)
Genome12
Negative-strand RNA viruses also share a number of other characteristics: most contain a viral envelope that surrounds the capsid, which encases the viral genome, −ssRNA virus genomes are usually linear, and it is common for their genome to be segmented. (wikipedia.org)
All −ssRNA genomes contain terminal inverted repeats, which are palindromic nucleotide sequences at each end of the genome. (wikipedia.org)
Replication of −ssRNA genomes is executed by RdRp, which initiates replication by binding to a leader sequence on the 3'-end (usually pronounced "three prime end") of the genome. (wikipedia.org)
RdRp then uses the negative sense genome as a template to synthesize a positive-sense antigenome. (wikipedia.org)
Thereafter, RdRp ignores all transcription signals on the antigenome and synthesizes a copy of the genome while using the antigenome as a template. (wikipedia.org)
Replication is executed while the genome is inside the nucleocapsid, and RdRp unveils the capsid and translocates along the genome during replication. (wikipedia.org)
The virion RNA is infectious and serves as both the genome and viral messenger RNA. (expasy.org)
The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA(+) genomes. (expasy.org)
Non-enveloped, spherical, about 30 nm in diameter, pseudo T=3 icosahedral capsid surrounding the naked RNA genome. (expasy.org)
Monopartite, linear ssRNA(+) genome of 7.8 kb, polyadenylated, composed of a single ORF encoding a polyprotein. (expasy.org)
The genome consists of either RNA or DNA and can be single- or double-stranded, linear or circular. (fortunejournals.com)
DsRNA4
They are descended from a common ancestor that was a double-stranded RNA (dsRNA) virus, and they are considered to be a sister clade of reoviruses, which are dsRNA viruses. (wikipedia.org)
We have therefore tested the DCL4 functionality in processing exogenous dsRNA-like substrates, such as a replicase-assisted viral replicon defective-interfering RNA and RNA hairpin substrates, or endogenous antisense transcripts. (biomedcentral.com)
Plant Dicer-like proteins (DCLs) are RNase III, double-stranded RNA (dsRNA)-specific endonucleases with specialized functions in producing short (s)RNAs of 21- to 24-nucleotides (nt), including micro (mi)RNAs and short interfering (si)RNAs of endogenous or viral origin. (biomedcentral.com)
These led to the conclusion that DCL4 and DCL2 act redundantly and one of the two alone is sufficient to perceive dsRNA of viral origin, process it into siRNA of viral origin (vsiRNAs) and initiate the plant RNA silencing-based antiviral defense [ 14 ]. (biomedcentral.com)
Viruses17
Negative-strand RNA viruses (−ssRNA viruses) are a group of related viruses that have negative-sense, single-stranded genomes made of ribonucleic acid (RNA). (wikipedia.org)
Negative-strand RNA viruses constitute the phylum Negarnaviricota, in the kingdom Orthornavirae and realm Riboviria. (wikipedia.org)
Negative-strand RNA viruses are closely associated with arthropods and can be informally divided between those that are reliant on arthropods for transmission and those that are descended from arthropod viruses but can now replicate in vertebrates without the aid of arthropods. (wikipedia.org)
Prominent arthropod-borne −ssRNA viruses include the Rift Valley fever virus and the tomato spotted wilt virus. (wikipedia.org)
Notable vertebrate −ssRNA viruses include the Ebola virus, hantaviruses, influenza viruses, the Lassa fever virus, and the rabies virus. (wikipedia.org)
All viruses in Negarnaviricota are negative-sense, single-stranded RNA (−ssRNA) viruses. (wikipedia.org)
Excluding viruses in the genus Tenuivirus and some in the family Chuviridae, all −ssRNA viruses have linear rather than circular genomes, and the genomes may be segmented or non-segmented. (wikipedia.org)
Infections caused by several positive-stranded RNA viruses allow the characterization of DCLs involved in the RNA-silencing-based antiviral immune responses of plants. (biomedcentral.com)
Replication of plus-strand RNA viruses depends on recruited host factors that aid several critical steps during replication. (prolekarniky.cz)
Thus, two small RNA viruses, which do not code for their own helicases, seems to recruit a host RNA helicase to aid their replication in infected cells. (prolekarniky.cz)
All eukaryotic plus-stranded (+)RNA viruses have similar replication cycles in infected cells. (prolekarniky.cz)
The single-stranded (+)-RNA viruses comprise the largest group of viruses, which includes pathogens such as Dengue virus, Corona virus and West Nile virus. (fortunejournals.com)
Studies of the mechanism of Qβ infection can increase our general understanding of the single-stranded (+)-RNA viruses, which can be exploited in the pursuit to treat and prevent diseases caused by pathogenic (+)-RNA viruses. (fortunejournals.com)
The largest group is the single-stranded, positive sense (+)-RNA viruses, which comprises more than a third of all viruses. (fortunejournals.com)
The group of (+)-RNA viruses includes a number of pathogenic viruses such as Polio virus, Hepatitis A and C, Dengue virus and Severe Acute Respiratory Syndrome coronavirus [3]. (fortunejournals.com)
The (+)-RNA viruses have been used in the development of vaccines, as imaging tools and in virus inactivation studies [4, 5]. (fortunejournals.com)
Genomes2
They have genomes made of RNA, which are single instead of double-stranded. (wikipedia.org)
In genomes that encode more than one transcribable portion, RdRp can continue scanning to the next start sequence to continue with transcription. (wikipedia.org)
Proteins10
As new nucleotide sequences are synthesized by RdRp, capsid proteins are assembled and encapsidate the newly replicate viral RNA. (wikipedia.org)
The viral RNA is translated to produce the two proteins necessary for RNA synthesis (replication and transcription). (expasy.org)
The polyprotein is initially processed by the viral protease into various precursor and mature proteins to yield the structural proteins, replicase, VPg, and a number of proteins that modify the host cell, ultimately leading to cell lysis . (expasy.org)
In plants, RNase III Dicer-like proteins (DCLs) act as sensors of dsRNAs and process them into short 21- to 24-nucleotide (nt) (s)RNAs. (biomedcentral.com)
Altogether, the two host factors enhance TBSV replication synergistically by interacting with the viral (−)RNA and the replication proteins. (prolekarniky.cz)
Among the identified host proteins are RNA-binding proteins, such as translation factors, ribosomal proteins and RNA-modifying enzymes [1] . (prolekarniky.cz)
The co-opted host proteins likely affect several steps in viral RNA replication, including the assembly of the replicase complex and/or viral RNA synthesis. (prolekarniky.cz)
We studied the course of infection by analysing the production of viral RNA, proteins and phage particles produced in the cell-free reactions. (fortunejournals.com)
The replication of the viral RNA was determined by RT-PCR, while the translation of the viral proteins was examined by radiolabelling, and the production of infectious phage particles was evaluated by double-layered plaque assays. (fortunejournals.com)
Specifically, the viral RNA was replicated, the viral proteins were translated, and infectious phage particles were produced in the cell-free infection systems. (fortunejournals.com)
Capsid1
The capsid protein is directly expressed from RNA-2. (expasy.org)
Replication4
Subgenomic RNAs may be synthesized during replication of RNA-1 and RNA-2 and give rise to the movement protein and viral suppressor of RNA silencing . (expasy.org)
Conversely, DCL4 did not efficiently process a replicase-assisted viral replicon in vivo, providing evidence that viral RNAs are not accessible to DCL4 in membranes associated in active replication. (biomedcentral.com)
In this paper, we show that an essential translation factor, Ded1p DEAD-box RNA helicase of yeast, directly affects replication of Tomato bushy stunt virus (TBSV). (prolekarniky.cz)
However, the functions of host factors in (+)RNAvirus replication are known only for a small number of host factors [1] - [9] . (prolekarniky.cz)
Double-stranded1
The latter function is associated with the ability of RNA to form double-stranded (ds) or ds-like secondary structures. (biomedcentral.com)
Ribonucleic1
Ribonucleic acid (RNA) has multiple roles in cellular functions, from coding genes to non-coding regulatory activities. (biomedcentral.com)
Assay1
In addition, we have developed an in vitro assay for Flock house virus (FHV), a small RNA virus of insects, that also demonstrated positive effect on FHV replicase activity by the added Ded1p helicase. (prolekarniky.cz)
Binds2
When replicating the antigenome, RdRp first binds to the trailer sequence on the 3'-end of the antigenome. (wikipedia.org)
We also find that Ded1p is a component of the tombusvirus replicase complex and Ded1p binds to the 3′-end of the viral minus-stranded RNA. (prolekarniky.cz)
Complexes2
In turn, miRNAs and siRNAs guide the effector Argonautes (AGOs)-containing complexes to silence RNA target transcripts. (biomedcentral.com)
After the assembly of the membrane-bound viral replicase complexes (VRC), the viral replicase uses the viral RNA as a template to produce complementary (−)RNA. (prolekarniky.cz)
Synthesis2
The in vitro data show that Ded1p plays a role in enhancing plus-strand synthesis by the viral replicase. (prolekarniky.cz)
The data obtained with wt and ATPase deficient Ded1p mutants support the model that Ded1p unwinds local structures at the 3′-end of the TBSV (−)RNA, rendering the RNA compatible for initiation of (+)-strand synthesis. (prolekarniky.cz)
Eukaryotic1
The simplest form of RNA silencing, widely known as RNA interference (RNAi), is conserved in diverse eukaryotic species, including the fungal kingdom, but has been lost in the model budding yeast, Saccharomyces cerevisiae [ 15 ]. (biomedcentral.com)
Sequences1
Primers for RT-LAMP or RT-RPA can be designed for specific viral RNA sequences, and the amplification methods are used before the Cas enzyme detection step, to multiply detection signals from the specific nucleic acid sequences. (nature.com)
Transcription3
After capping the mRNA, RdRp initiates transcription at a gene start signal and later terminates transcription upon reaching a gene end signal. (wikipedia.org)
At the end of transcription, RdRp synthesizes a polyadenylated tail (poly (A) tail) consisting of hundreds of adenines in the mRNA's 3-end, which may be done by stuttering on a sequence of uracils. (wikipedia.org)
Quantitative real-time PCR with reverse transcription (RT-qPCR), which measures the quantity of viral RNAs, remains the gold-standard technique for SARS-CoV-2 virus detection 1 . (nature.com)
Methods1
RT-RPA and RT-LAMP are highly sensitive methods, but can suffer from nonspecific amplification under isothermal conditions, leading to false-positive results when used for viral RNA detections. (nature.com)
Virus1
Negarnaviricota takes the first part of its name from Latin nega, meaning negative, the middle part rna refers to RNA, and the final part, -viricota, is the suffix used for virus phyla. (wikipedia.org)
Directly1
The RNA-1 5'proximal ORFs are directly translated to produce the viral constituents of the replicase complex. (expasy.org)
Internal1
The RdRp recognizes internal subgenomic promoters on the negative-sense RNA to transcribe the 3'co-terminal subgenomic RNAs that will generate the movement protein and viral suppressor of RNA silencing . (expasy.org)
Role1
The results all together confirm the role of sense/antisense RNA-based regulation of gene expression, expanding the sense/antisense atlas of S. cerevisiae . (biomedcentral.com)
Translated from subgenomic2
The downstream genes encoding the movement proteins and capsid protein (which acts as a viral suppressor of RNA silencing ) are translated from subgenomic RNAs. (expasy.org)
The downstream genes encoding the movement protein , viral suppressor of RNA silencing (VSR) and capsid proteins are usually translated from subgenomic RNAs. (expasy.org)
Single-stranded1
All viruses in Negarnaviricota are negative-sense, single-stranded RNA (−ssRNA) viruses. (wikipedia.org)
Suppression1
RdRp is translated through suppression of termination at the end of ORF1. (expasy.org)
Sequence2
When replicating the antigenome, RdRp first binds to the trailer sequence on the 3'-end of the antigenome. (wikipedia.org)
At the leader sequence, RdRp synthesizes a 5-'end (usually pronounced "five prime end") triphosphate-leader RNA and either, in the case of the subphylum Haploviricotina, caps the 5'-end or, in the case of the subphylum Polyploviricotina, snatches a cap from a host mRNA and attaches it to the viral mRNA so that the mRNA can be translated by the host cell's ribosomes. (wikipedia.org)
Gene1
When V. dahliae protoplasts were transformed with short interfering RNAs (siRNAs) targeting the VdAAC gene, fungal growth and sporulation were significantly inhibited. (preprints.org)
Poly1
After the poly (A) tail is constructed, the mRNA is released by RdRp. (wikipedia.org)
Family1
This family contains positive stranded RNA that infects mammals [11]. (kenyon.edu)
Members1
Within the phylum, there are two major branches that form two subphyla: Haploviricotina, whose members are mostly non-segmented and which encode an RdRp that synthesizes caps on mRNA, and Polyploviricotina, whose members are segmented and which encode an RdRp that snatches caps from host mRNAs. (wikipedia.org)