Reoviridae
Orbivirus
Coltivirus
Bluetongue virus
Orthoreovirus
Bluetongue
RNA, Double-Stranded
Ceratopogonidae
Carps
Cryoelectron Microscopy
Rotavirus
Viral Nonstructural Proteins
Viral Core Proteins
Molecular Sequence Data
Virion
Microscopy, Electron
Sequence Analysis, DNA
Base Sequence
Amino Acid Sequence
Virus Replication
Paramyxoviridae Infections
Parainfluenza Virus 1, Human
Influenza, Human
Reovirus virion-like particles obtained by recoating infectious subvirion particles with baculovirus-expressed sigma3 protein: an approach for analyzing sigma3 functions during virus entry. (1/1038)
Structure-function studies with mammalian reoviruses have been limited by the lack of a reverse-genetic system for engineering mutations into the viral genome. To circumvent this limitation in a partial way for the major outer-capsid protein sigma3, we obtained in vitro assembly of large numbers of virion-like particles by binding baculovirus-expressed sigma3 protein to infectious subvirion particles (ISVPs) that lack sigma3. A level of sigma3 binding approaching 100% of that in native virions was routinely achieved. The sigma3 coat in these recoated ISVPs (rcISVPs) appeared very similar to that in virions by electron microscopy and three-dimensional image reconstruction. rcISVPs retained full infectivity in murine L cells, allowing their use to study sigma3 functions in virus entry. Upon infection, rcISVPs behaved identically to virions in showing an extended lag phase prior to exponential growth and in being inhibited from entering cells by either the weak base NH4Cl or the cysteine proteinase inhibitor E-64. rcISVPs also mimicked virions in being incapable of in vitro activation to mediate lysis of erythrocytes and transcription of the viral mRNAs. Last, rcISVPs behaved like virions in showing minor loss of infectivity at 52 degrees C. Since rcISVPs contain virion-like levels of sigma3 but contain outer-capsid protein mu1/mu1C mostly cleaved at the delta-phi junction as in ISVPs, the fact that rcISVPs behaved like virions (and not ISVPs) in all of the assays that we performed suggests that sigma3, and not the delta-phi cleavage of mu1/mu1C, determines the observed differences in behavior between virions and ISVPs. To demonstrate the applicability of rcISVPs for genetic studies of protein functions in reovirus entry (an approach that we call recoating genetics), we used chimeric sigma3 proteins to localize the primary determinants of a strain-dependent difference in sigma3 cleavage rate to a carboxy-terminal region of the ISVP-bound protein. (+info)In vitro recoating of reovirus cores with baculovirus-expressed outer-capsid proteins mu1 and sigma3. (2/1038)
Reovirus outer-capsid proteins mu1, sigma3, and sigma1 are thought to be assembled onto nascent core-like particles within infected cells, leading to the production of progeny virions. Consistent with this model, we report the in vitro assembly of baculovirus-expressed mu1 and sigma3 onto purified cores that lack mu1, sigma3, and sigma1. The resulting particles (recoated cores, or r-cores) closely resembled native virions in protein composition (except for lacking cell attachment protein sigma1), buoyant density, and particle morphology by scanning cryoelectron microscopy. Transmission cryoelectron microscopy and image reconstruction of r-cores confirmed that they closely resembled virions in the structure of the outer capsid and revealed that assembly of mu1 and sigma3 onto cores had induced rearrangement of the pentameric lambda2 turrets into a conformation approximating that in virions. r-cores, like virions, underwent proteolytic conversion to particles resembling native ISVPs (infectious subvirion particles) in protein composition, particle morphology, and capacity to permeabilize membranes in vitro. r-cores were 250- to 500-fold more infectious than cores in murine L cells and, like virions but not ISVPs or cores, were inhibited from productively infecting these cells by the presence of either NH4Cl or E-64. The latter results suggest that r-cores and virions used similar routes of entry into L cells, including processing by lysosomal cysteine proteinases, even though the former particles lacked the sigma1 protein. To examine the utility of r-cores for genetic dissections of mu1 functions in reovirus entry, we generated r-cores containing a mutant form of mu1 that had been engineered to resist cleavage at the delta:phi junction during conversion to ISVP-like particles by chymotrypsin in vitro. Despite their deficit in delta:phi cleavage, these ISVP-like particles were fully competent to permeabilize membranes in vitro and to infect L cells in the presence of NH4Cl, providing new evidence that this cleavage is dispensable for productive infection. (+info)Reovirus type 3 clone 9 increases interleukin-1alpha level in the brain of neonatal, but not adult, mice. (3/1038)
Reovirus Type 3 clone 9 (T3C9)-induced lethal encephalitis is age dependent. We examined the effects of T3C9 inoculated into neonatal and adult mice by intracerebral, intramuscular, or peroral routes and the effect of lipopolysaccharide (LPS) on IL-1alpha levels in the blood and the brain. In parallel, we measured mice survival to T3C9 challenge, primary replication, and growth in and spread to the brain. The results show that T3C9 infection increased IL-1alpha only in the brain of neonatal mice, whereas LPS enhanced IL-1alpha in the brain and in the blood in both neonatal and adult mice. In neonatal mice, a T3C9-induced IL-1alpha increase coincided with viral replication-induced nervous tissue injury and preceded death. Anti-IL-1alpha antibody partially protected neonatal mice against T3C9 peroral challenge, further suggesting that this cytokine is involved in the mechanisms leading to lethal encephalitis. In adult mice, T3C9 was not lethal and did not modify IL-1alpha levels although it slowly replicated in nervous tissues when inoculated directly into the brain. Together, these results suggest that differences in nervous tissue response to T3C9 replication between newborn and adult mice could account in part for the age-dependent susceptibility to T3C9-induced lethal encephalitis. (+info)Two concentric protein shell structure with spikes of silkworm Bombyx mori cytoplasmic polyhedrosis virus revealed by small-angle neutron scattering using the contrast variation method. (4/1038)
The overall and internal structures of the silkworm Bombyx mori cytoplasmic polyhedrosis virus was investigated by small-angle neutron scattering using the contrast variation method. Data were collected in aqueous buffer solutions containing 0, 50, 75, and 100% D2O in the q range of 0.002 to 0.0774 A-1 at 5 degrees C. The radius of gyration at infinite contrast was estimated to be 336 A. The contrast matching point of the virus was determined to correspond to about 50% D2O level, evidence that the virus is composed of protein and nucleic acid. The virus was basically spherical and had a diameter of about 700 A. The main feature of its structure is the clustering of protein into two concentric shells separated by about 100 A. Most of the RNA moieties are located in the central core and between these two protein shells. However, the distance distribution function P(r) showed a minor distribution beyond a distance of r = 700 A, with a maximum particle distance of the virus of 1350 A. This is indicative of an external structure region with very low scattering density, in addition to the basic spherical structure. This external region is thought to correspond to twelve pyramidal protruding spikes shown by electron microscopic studies. (+info)Preliminary characterization of a reovirus isolated from golden ide Leuciscus idus melanotus. (5/1038)
Some characteristics of a reovirus recently isolated from golden ide Leuciscus idus melanotus and tentatively designated as golden ide reovirus (GIRV) were determined. Spherical non-enveloped particles with an outer capsid of about 70 nm and an inner capsid of about 50 nm were observed by electron microscopy. The density of the virus determined in CsCl gradients was 1.36 g ml-1. The genome contained 11 segments of dsRNA. GIRV differed from other aquareoviruses by a slight reduction of infectivity after treatment with chloroform and by the absence of forming syncytia in cell monolayers. (+info)Identification of grass carp haemorrhage virus as a new genogroup of aquareovirus. (6/1038)
Three aquareovirus strains isolated from grass carp (Ctenopharyngodon idellus), geoduck clams (Panope abrupta) and herring (Clupea harengus) in North America and Asia were examined by RNA-RNA blot hybridization to determine their genogroup. The isolates from clams and herring were identified as members of genogroup A, but the isolate from grass carp did not hybridize to any of the known genogroups, suggesting that this virus probably represents a new, seventh genogroup. (+info)Inhibitory role of the host apoptogenic gene PKR in the establishment of persistent infection by encephalomyocarditis virus in U937 cells. (7/1038)
Persistent infections by viruses such as HIV-1 and hepatitis B virus can pose long-term health hazards. Because establishment of persistent infections involves close interactions and adjustments in both host and virus, it would be informative to establish a paradigm with which a normally cytolytic viral infection can be easily converted to persistent infection, so that the different stages in developing persistent infection can be examined. Such a model system is described in this paper. Highly cytolytic encephalomyocarditis virus (EMCV) infection was shifted to persistent infection as a result of repressed expression of the double-stranded RNA-dependent protein kinase (PKR) in the promonocytic U937 cells. Because of the apoptogenic potential of PKR, a deficiency of PKR resulted in a delay in virus-induced apoptosis in EMCV-infected U937 cells, allowing the eventual establishment of persistent EMCV infection in these cells (U9K-AV2). That this was a bona fide persistent infection was demonstrated by the ability of infected cells to propagate as long-term virus-shedding cultures; electron microscopy studies showing presence of intracellular EMCV virions and chromatin condensation; detection of virus-induced chromosomal DNA fragmentation and sustained expression of apoptogenic p53 and IL-1beta converting enzyme; and demonstration of active EMCV transcription by reverse transcription-PCR. In addition, a host-virus coevolution was observed in U9K-AV2 cultures over time: U9K-AV2 cells exhibited slower growth rates, resistance to viral super-infection, and cessation of IFN-alpha synthesis, whereas the infectivity of EMCV was drastically attenuated. Finally, data are presented on the suitability of this model to study establishment of persistent infection by other viruses such as Sendai virus and reovirus. (+info)Mammalian reovirus M3 gene sequences and conservation of coiled-coil motifs near the carboxyl terminus of the microNS protein. (8/1038)
Nucleotide sequences of the mammalian orthoreovirus (reovirus) type 1 Lang and type 2 Jones M3 gene segments were newly determined. The nucleotide sequence of the reovirus type 3 Dearing M3 segment also was determined to compare with a previously reported M3 sequence for that isolate. Comparisons showed Lang and Dearing M3 to be more closely related than either was to Jones M3, consistent with previous findings for other reovirus gene segments. The microNS protein sequences deduced from each M3 segment were shown to be related in a similar pattern as the respective nucleotide sequences and to contain several regions of greater or less than average variability among the three isolates. Identification of conserved methionine codons near the 5' ends of the Lang, Jones, and Dearing M3 plus strands lent support to the hypothesis that microNSC, a smaller protein also encoded by M3, arises by translation initiation from a downstream methionine codon within the same open reading frame as microNS. Other analyses of the deduced protein sequences indicated that regions within the carboxyl-terminal third of microNS and microNSC from each isolate have a propensity to form alpha-helical coiled coils, most likely coiled-coil dimers. The new sequences will augment further studies on microNS and microNSC structure and function. (+info)Reoviridae is a family of double-stranded RNA viruses that are non-enveloped and have a segmented genome. The name "Reoviridae" is derived from Respiratory Enteric Orphan virus, as these viruses were initially discovered in respiratory and enteric (gastrointestinal) samples but did not appear to cause any specific diseases.
The family Reoviridae includes several important human pathogens such as rotaviruses, which are a major cause of severe diarrhea in young children worldwide, and orthoreoviruses, which can cause respiratory and systemic infections in humans. Additionally, many Reoviridae viruses infect animals, including birds, mammals, fish, and insects, and can cause a variety of diseases.
Reoviridae virions are typically composed of multiple protein layers that encase the genomic RNA segments. The family is divided into two subfamilies, Sedoreovirinae and Spinareovirinae, based on structural features and genome organization. Reoviruses have a complex replication cycle that involves multiple steps, including attachment to host cells, uncoating of the viral particle, transcription of the genomic RNA, translation of viral proteins, packaging of new virions, and release from infected cells.
Reoviridae infections refer to diseases caused by the Reoviridae family of viruses, which are non-enveloped, double-stranded RNA viruses. These viruses are widespread and can infect a variety of hosts, including humans, animals, and insects. The infection typically causes mild respiratory or gastrointestinal symptoms in humans, such as cough, runny nose, sore throat, and diarrhea. In some cases, Reoviridae infections may also lead to more severe diseases, such as meningitis or encephalitis, particularly in immunocompromised individuals. However, it's worth noting that many Reoviridae infections are asymptomatic and do not cause any noticeable illness.
Reoviridae viruses include several genera, such as Orthoreovirus, Rotavirus, Coltivirus, and Orbivirus, among others. Some of the most well-known human pathogens in this family include Rotaviruses, which are a leading cause of severe diarrheal disease in young children worldwide, and Orthoreoviruses, which can cause respiratory illnesses.
Treatment for Reoviridae infections is generally supportive, focusing on managing symptoms such as fever, dehydration, and pain. Antiviral medications are not typically used to treat these infections. Prevention measures include good hygiene practices, such as handwashing and avoiding close contact with infected individuals, as well as vaccination against specific Reoviridae viruses, such as Rotavirus vaccines.
Orbivirus is a genus of viruses in the family Sedoreoviridae, order Reovirales. They are non-enveloped, double-stranded RNA viruses with an icosahedral symmetry and a genome consisting of 10 segments. Orbiviruses infect various species of animals, including humans, causing a range of diseases such as African horse sickness, blue tongue disease, and Colorado tick fever. The virus is typically transmitted through the bite of arthropod vectors, such as ticks and mosquitoes, or through contact with infected animal secretions or contaminated food and water.
Coltivirus is a genus of viruses in the Reoviridae family, which are double-stranded RNA viruses. Coltiviruses are known to infect and cause disease in humans and animals, particularly rodents. The name "coltivirus" comes from "COLumbia-TIbet" viruses, as the first two isolates of this genus were found in ticks in these locations.
The most well-known coltivirus is Colorado tick fever virus (CTFV), which is transmitted to humans through the bite of infected ticks, primarily the Rocky Mountain wood tick (Dermacentor andersoni). CTFV infection can cause a flu-like illness with symptoms such as fever, chills, headache, muscle pain, and fatigue. In some cases, more severe complications like meningitis or encephalitis may occur, although this is rare.
Prevention of coltivirus infections primarily involves avoiding tick bites through the use of insect repellents, wearing protective clothing, and checking for and removing ticks promptly after being outdoors in areas where infected ticks are known to be present. There are currently no specific antiviral treatments available for coltivirus infections, and treatment is generally supportive, focusing on relieving symptoms and managing complications as they arise.
Bluetongue virus (BTV) is an infectious agent that causes Bluetongue disease, a non-contagious viral disease affecting sheep and other ruminants. It is a member of the Orbivirus genus within the Reoviridae family. The virus is transmitted by biting midges of the Culicoides species and can infect various animals such as sheep, cattle, goats, and wild ruminants.
The virus has a double-stranded RNA genome and consists of ten segments that encode seven structural and four non-structural proteins. The clinical signs of Bluetongue disease in sheep include fever, salivation, swelling of the head and neck, nasal discharge, and respiratory distress, which can be severe or fatal. In contrast, cattle usually show milder symptoms or are asymptomatic, although they can serve as reservoirs for the virus.
Bluetongue virus is an important veterinary pathogen that has a significant economic impact on the global sheep industry. The disease is prevalent in many parts of the world, particularly in tropical and subtropical regions, but has also spread to temperate areas due to climate change and the movement of infected animals. Prevention and control measures include vaccination, insect control, and restricting the movement of infected animals.
Orthoreovirus is a type of virus that belongs to the family Reoviridae. These are non-enveloped viruses with a double-stranded RNA genome. Orthoreoviruses are further classified into three main serotypes (Orthoreovirus 1-3), and they are known to infect both humans and animals, including birds and mammals.
In humans, orthoreovirus infections are usually mild or asymptomatic but can sometimes cause respiratory or gastrointestinal symptoms, particularly in children. The virus is typically transmitted through respiratory droplets or the fecal-oral route. Once inside the host, the virus infects and replicates within cells of the respiratory or intestinal tract, leading to tissue damage and the release of pro-inflammatory cytokines.
Orthoreovirus infections are generally self-limiting, and treatment is typically supportive. However, there is ongoing research into the potential use of orthoreoviruses as oncolytic viruses for cancer therapy, as they have been shown to selectively infect and kill cancer cells while leaving normal cells unharmed.
Bluetongue is a viral disease that primarily affects sheep and some species of cattle, goats, and wild ruminants. The disease is named for the bluish discoloration of the tongue that can occur in severe cases. It is transmitted by midges (Culicoides spp.) and occurs mainly in tropical and subtropical regions around the world.
The symptoms of Bluetongue include fever, salivation, difficulty breathing, swelling of the head and neck, and lameness. In severe cases, it can cause death. The disease is not contagious between animals and cannot be spread through contact or ingestion of contaminated feed or water.
There are several different serotypes of Bluetongue virus, and immunity to one serotype does not provide cross-protection against other serotypes. Vaccination is available for some serotypes in certain regions, but it may not be effective against all serotypes. Control measures typically focus on reducing exposure to midges through the use of insect repellents, screens, and other barriers.
I'm happy to help! However, it seems there might be a slight misunderstanding in your question. RNA, or ribonucleic acid, is typically single-stranded. Unlike DNA, which is double-stranded and forms a double helix, RNA usually exists as a single strand of nucleotides.
There are exceptions to this rule, such as certain types of RNA molecules that can form double-stranded structures in specific contexts. For example:
1. Double-Stranded RNA (dsRNA) viruses: These viruses have genomes made entirely of RNA, which is double-stranded throughout or partially double-stranded. The dsRNA viruses include important pathogens such as rotaviruses and reoviruses.
2. Hairpin loops in RNA structures: Some single-stranded RNA molecules can fold back on themselves to form short double-stranded regions, called hairpin loops, within their overall structure. These are often found in ribosomal RNA (rRNA), transfer RNA (tRNA), and messenger RNA (mRNA) molecules.
So, while 'double-stranded RNA' is not a standard medical definition for RNA itself, there are specific instances where RNA can form double-stranded structures as described above.
A viral genome is the genetic material (DNA or RNA) that is present in a virus. It contains all the genetic information that a virus needs to replicate itself and infect its host. The size and complexity of viral genomes can vary greatly, ranging from a few thousand bases to hundreds of thousands of bases. Some viruses have linear genomes, while others have circular genomes. The genome of a virus also contains the information necessary for the virus to hijack the host cell's machinery and use it to produce new copies of the virus. Understanding the genetic makeup of viruses is important for developing vaccines and antiviral treatments.
Ceratopogonidae is a family of small flies, also known as biting midges or no-see-ums. They are characterized by their slender segmented bodies, feathery antennae, and wings with extensive venation. Some species in this family are known to be vectors of various diseases, such as human and animal forms of filariasis, blue tongue virus in sheep, and several viral diseases in horses. The larvae of these flies are aquatic or semi-aquatic and can be found in a variety of habitats including wet soil, decaying vegetation, and freshwater bodies.
I cannot provide a medical definition for "carps" as it is not a term used in medicine. The term "carp" refers to a type of freshwater fish that belongs to the family Cyprinidae. If you meant to ask about something else, please provide more context or clarify your question.
A viral RNA (ribonucleic acid) is the genetic material found in certain types of viruses, as opposed to viruses that contain DNA (deoxyribonucleic acid). These viruses are known as RNA viruses. The RNA can be single-stranded or double-stranded and can exist as several different forms, such as positive-sense, negative-sense, or ambisense RNA. Upon infecting a host cell, the viral RNA uses the host's cellular machinery to translate the genetic information into proteins, leading to the production of new virus particles and the continuation of the viral life cycle. Examples of human diseases caused by RNA viruses include influenza, COVID-19 (SARS-CoV-2), hepatitis C, and polio.
Cryo-electron microscopy (Cryo-EM) is a type of electron microscopy where the sample is studied at cryogenic temperatures, typically liquid nitrogen temperatures. This technique is used to investigate the structure and shape of biological molecules and complexes, viruses, and other nanoscale particles.
In Cryo-EM, the sample is rapidly frozen to preserve its natural structure and then imaged using a beam of electrons. The images are collected at different angles and then computationally combined to generate a 3D reconstruction of the sample. This technique allows researchers to visualize biological structures in their native environment with near-atomic resolution, providing valuable insights into their function and behavior.
Cryo-EM has become an increasingly popular tool in structural biology due to its ability to image large and complex structures that are difficult or impossible to crystallize for X-ray crystallography. It has been used to determine the structures of many important biological molecules, including membrane proteins, ribosomes, viruses, and protein complexes involved in various cellular processes.
Rotavirus is a genus of double-stranded RNA virus in the Reoviridae family, which is a leading cause of severe diarrhea and gastroenteritis in young children and infants worldwide. The virus infects and damages the cells lining the small intestine, resulting in symptoms such as vomiting, watery diarrhea, abdominal cramps, and fever.
Rotavirus is highly contagious and can be spread through contact with infected individuals or contaminated surfaces, food, or water. The virus is typically transmitted via the fecal-oral route, meaning that it enters the body through the mouth after coming into contact with contaminated hands, objects, or food.
Rotavirus infections are often self-limiting and resolve within a few days to a week, but severe cases can lead to dehydration, hospitalization, and even death, particularly in developing countries where access to medical care and rehydration therapy may be limited. Fortunately, there are effective vaccines available that can prevent rotavirus infection and reduce the severity of symptoms in those who do become infected.
Capsid proteins are the structural proteins that make up the capsid, which is the protective shell of a virus. The capsid encloses the viral genome and helps to protect it from degradation and detection by the host's immune system. Capsid proteins are typically arranged in a symmetrical pattern and can self-assemble into the capsid structure when exposed to the viral genome.
The specific arrangement and composition of capsid proteins vary between different types of viruses, and they play important roles in the virus's life cycle, including recognition and binding to host cells, entry into the cell, and release of the viral genome into the host cytoplasm. Capsid proteins can also serve as targets for antiviral therapies and vaccines.
A capsid is the protein shell that encloses and protects the genetic material of a virus. It is composed of multiple copies of one or more proteins that are arranged in a specific structure, which can vary in shape and symmetry depending on the type of virus. The capsid plays a crucial role in the viral life cycle, including protecting the viral genome from host cell defenses, mediating attachment to and entry into host cells, and assisting with the assembly of new virus particles during replication.
RNA viruses are a type of virus that contain ribonucleic acid (RNA) as their genetic material, as opposed to deoxyribonucleic acid (DNA). RNA viruses replicate by using an enzyme called RNA-dependent RNA polymerase to transcribe and replicate their RNA genome.
There are several different groups of RNA viruses, including:
1. Negative-sense single-stranded RNA viruses: These viruses have a genome that is complementary to the mRNA and must undergo transcription to produce mRNA before translation can occur. Examples include influenza virus, measles virus, and rabies virus.
2. Positive-sense single-stranded RNA viruses: These viruses have a genome that can serve as mRNA and can be directly translated into protein after entry into the host cell. Examples include poliovirus, rhinoviruses, and coronaviruses.
3. Double-stranded RNA viruses: These viruses have a genome consisting of double-stranded RNA and use a complex replication strategy involving both transcription and reverse transcription. Examples include rotaviruses and reoviruses.
RNA viruses are known to cause a wide range of human diseases, ranging from the common cold to more severe illnesses such as hepatitis C, polio, and COVID-19. Due to their high mutation rates and ability to adapt quickly to new environments, RNA viruses can be difficult to control and treat with antiviral drugs or vaccines.
Viral nonstructural proteins (NS) are viral proteins that are not part of the virion structure. They play various roles in the viral life cycle, such as replication of the viral genome, transcription, translation regulation, and modulation of the host cell environment to favor virus replication. These proteins are often produced in large quantities during infection and can manipulate or disrupt various cellular pathways to benefit the virus. They may also be involved in evasion of the host's immune response. The specific functions of viral nonstructural proteins vary depending on the type of virus.
Viral core proteins are the structural proteins that make up the viral capsid or protein shell, enclosing and protecting the viral genome. These proteins play a crucial role in the assembly of the virion, assist in the infection process by helping to deliver the viral genome into the host cell, and may also have functions in regulating viral replication. The specific composition and structure of viral core proteins vary among different types of viruses.
Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.
Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.
Viral proteins are the proteins that are encoded by the viral genome and are essential for the viral life cycle. These proteins can be structural or non-structural and play various roles in the virus's replication, infection, and assembly process. Structural proteins make up the physical structure of the virus, including the capsid (the protein shell that surrounds the viral genome) and any envelope proteins (that may be present on enveloped viruses). Non-structural proteins are involved in the replication of the viral genome and modulation of the host cell environment to favor viral replication. Overall, a thorough understanding of viral proteins is crucial for developing antiviral therapies and vaccines.
A virion is the complete, infectious form of a virus outside its host cell. It consists of the viral genome (DNA or RNA) enclosed within a protein coat called the capsid, which is often surrounded by a lipid membrane called the envelope. The envelope may contain viral proteins and glycoproteins that aid in attachment to and entry into host cells during infection. The term "virion" emphasizes the infectious nature of the virus particle, as opposed to non-infectious components like individual capsid proteins or naked viral genome.
Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).
In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.
In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.
REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.
Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.
DNA Sequence Analysis is the systematic determination of the order of nucleotides in a DNA molecule. It is a critical component of modern molecular biology, genetics, and genetic engineering. The process involves determining the exact order of the four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - in a DNA molecule or fragment. This information is used in various applications such as identifying gene mutations, studying evolutionary relationships, developing molecular markers for breeding, and diagnosing genetic diseases.
The process of DNA Sequence Analysis typically involves several steps, including DNA extraction, PCR amplification (if necessary), purification, sequencing reaction, and electrophoresis. The resulting data is then analyzed using specialized software to determine the exact sequence of nucleotides.
In recent years, high-throughput DNA sequencing technologies have revolutionized the field of genomics, enabling the rapid and cost-effective sequencing of entire genomes. This has led to an explosion of genomic data and new insights into the genetic basis of many diseases and traits.
A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.
An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.
A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.
Virus replication is the process by which a virus produces copies or reproduces itself inside a host cell. This involves several steps:
1. Attachment: The virus attaches to a specific receptor on the surface of the host cell.
2. Penetration: The viral genetic material enters the host cell, either by invagination of the cell membrane or endocytosis.
3. Uncoating: The viral genetic material is released from its protective coat (capsid) inside the host cell.
4. Replication: The viral genetic material uses the host cell's machinery to produce new viral components, such as proteins and nucleic acids.
5. Assembly: The newly synthesized viral components are assembled into new virus particles.
6. Release: The newly formed viruses are released from the host cell, often through lysis (breaking) of the cell membrane or by budding off the cell membrane.
The specific mechanisms and details of virus replication can vary depending on the type of virus. Some viruses, such as DNA viruses, use the host cell's DNA polymerase to replicate their genetic material, while others, such as RNA viruses, use their own RNA-dependent RNA polymerase or reverse transcriptase enzymes. Understanding the process of virus replication is important for developing antiviral therapies and vaccines.
Viral pneumonia is a type of pneumonia caused by viral infection. It primarily affects the upper and lower respiratory tract, leading to inflammation of the alveoli (air sacs) in the lungs. This results in symptoms such as cough, difficulty breathing, fever, fatigue, and chest pain. Common viruses that can cause pneumonia include influenza virus, respiratory syncytial virus (RSV), and adenovirus. Viral pneumonia is often milder than bacterial pneumonia but can still be serious, especially in young children, older adults, and people with weakened immune systems. Treatment typically involves supportive care, such as rest, hydration, and fever reduction, while the body fights off the virus. In some cases, antiviral medications may be used to help manage symptoms and prevent complications.
Pneumonia is an infection or inflammation of the alveoli (tiny air sacs) in one or both lungs. It's often caused by bacteria, viruses, or fungi. Accumulated pus and fluid in these air sacs make it difficult to breathe, which can lead to coughing, chest pain, fever, and difficulty breathing. The severity of symptoms can vary from mild to life-threatening, depending on the underlying cause, the patient's overall health, and age. Pneumonia is typically diagnosed through a combination of physical examination, medical history, and diagnostic tests such as chest X-rays or blood tests. Treatment usually involves antibiotics for bacterial pneumonia, antivirals for viral pneumonia, and supportive care like oxygen therapy, hydration, and rest.
Bacterial pneumonia is a type of lung infection that's caused by bacteria. It can affect people of any age, but it's more common in older adults, young children, and people with certain health conditions or weakened immune systems. The symptoms of bacterial pneumonia can vary, but they often include cough, chest pain, fever, chills, and difficulty breathing.
The most common type of bacteria that causes pneumonia is Streptococcus pneumoniae (pneumococcus). Other types of bacteria that can cause pneumonia include Haemophilus influenzae, Staphylococcus aureus, and Mycoplasma pneumoniae.
Bacterial pneumonia is usually treated with antibiotics, which are medications that kill bacteria. The specific type of antibiotic used will depend on the type of bacteria causing the infection. It's important to take all of the prescribed medication as directed, even if you start feeling better, to ensure that the infection is completely cleared and to prevent the development of antibiotic resistance.
In severe cases of bacterial pneumonia, hospitalization may be necessary for close monitoring and treatment with intravenous antibiotics and other supportive care.
Paramyxoviridae is a family of viruses that includes several important pathogens causing respiratory infections in humans and animals. According to the medical perspective, Paramyxoviridae infections refer to the diseases caused by these viruses.
Some notable human paramyxovirus infections include:
1. Respiratory Syncytial Virus (RSV) Infection: RSV is a common cause of respiratory tract infections, particularly in young children and older adults. It can lead to bronchiolitis and pneumonia, especially in infants and patients with compromised immune systems.
2. Measles (Rubeola): Measles is a highly contagious viral disease characterized by fever, cough, coryza (runny nose), conjunctivitis, and a maculopapular rash. It can lead to severe complications such as pneumonia, encephalitis, and even death, particularly in malnourished children and individuals with weakened immune systems.
3. Parainfluenza Virus Infection: Parainfluenza viruses are responsible for upper and lower respiratory tract infections, including croup, bronchitis, and pneumonia. They mainly affect young children but can also infect adults, causing mild to severe illnesses.
4. Mumps: Mumps is a contagious viral infection that primarily affects the salivary glands, causing painful swelling. It can lead to complications such as meningitis, encephalitis, deafness, and orchitis (inflammation of the testicles) in rare cases.
5. Human Metapneumovirus (HMPV) Infection: HMPV is a respiratory virus that can cause upper and lower respiratory tract infections, similar to RSV and parainfluenza viruses. It mainly affects young children and older adults, leading to bronchitis, pneumonia, and exacerbations of chronic lung diseases.
Prevention strategies for Paramyxoviridae infections include vaccination programs, practicing good personal hygiene, and implementing infection control measures in healthcare settings.
Parainfluenza Virus 1, Human (HPIV-1) is a type of respiratory virus that belongs to the family Paramyxoviridae and genus Respirovirus. It is one of the four serotypes of human parainfluenza viruses (HPIVs), which are important causes of acute respiratory infections in children, immunocompromised individuals, and the elderly.
HPIV-1 primarily infects the upper respiratory tract, causing symptoms such as cough, runny nose, sore throat, and fever. However, it can also cause lower respiratory tract infections, including bronchitis, bronchiolitis, and pneumonia, particularly in young children and infants.
HPIV-1 is transmitted through respiratory droplets or direct contact with infected individuals. The incubation period for HPIV-1 infection ranges from 2 to 7 days, after which symptoms can last for up to 10 days. There is no specific antiviral treatment available for HPIV-1 infections, and management typically involves supportive care such as hydration, fever reduction, and respiratory support if necessary.
Prevention measures include good hand hygiene, avoiding close contact with infected individuals, and practicing cough etiquette. Vaccines are not currently available for HPIV-1 infections, but research is ongoing to develop effective vaccines against these viruses.
Influenza, also known as the flu, is a highly contagious viral infection that attacks the respiratory system of humans. It is caused by influenza viruses A, B, or C and is characterized by the sudden onset of fever, chills, headache, muscle pain, sore throat, cough, runny nose, and fatigue. Influenza can lead to complications such as pneumonia, bronchitis, and ear infections, and can be particularly dangerous for young children, older adults, pregnant women, and people with weakened immune systems or chronic medical conditions. The virus is spread through respiratory droplets produced when an infected person coughs, sneezes, or talks, and can also survive on surfaces for a period of time. Influenza viruses are constantly changing, which makes it necessary to get vaccinated annually to protect against the most recent and prevalent strains.
'Influenza A Virus, H1N1 Subtype' is a specific subtype of the influenza A virus that causes flu in humans and animals. It contains certain proteins called hemagglutinin (H) and neuraminidase (N) on its surface, with this subtype specifically having H1 and N1 antigens. The H1N1 strain is well-known for causing the 2009 swine flu pandemic, which was a global outbreak of flu that resulted in significant morbidity and mortality. This subtype can also cause seasonal flu, although the severity and symptoms may vary. It is important to note that influenza viruses are constantly changing, and new strains or subtypes can emerge over time, requiring regular updates to vaccines to protect against them.
Sedoreoviridae
Viral disease
Mammalian orthoreovirus
Above Maiden virus
Peruvian horse sickness virus
Double-stranded RNA viruses
African horse sickness
Kadipiro virus
Viral replication
Coltivirus
RNA virus
Avian orthoreovirus
Sedoreovirinae
Lebombo virus
Fiji disease virus
Reverse genetics
Equine encephalosis virus
Rice dwarf virus
List of insect-borne diseases
Spinareovirinae
Piscine orthoreovirus
Rotavirus
Orbivirus
Mimoreovirus
Acatinga virus
Maize rough dwarf virus
Rice ragged stunt virus
Seadornavirus
Banna virus
Oat sterile dwarf virus
Reoviridae | Profiles RNS
Reoviridae - wikidoc
AGROVOC: AGROVOC: Reoviridae
Reoviridae Infections | Profiles RNS
Reoviridae sigma-1 protein family | canSARS
What's in the Collection | Division of Vector-Borne Diseases | NCEZID | CDC
Sedoreoviridae - Wikipedia
ArboCat Virus: Seletar (SELV)
ArboCat Virus: Kemerovo (KEMV)
Discovery and Characterization of Bukakata orbivirus (Reoviridae:Orbivirus), a Novel Virus from a Ugandan Bat
ID AF403406; SV 1; linear; genomic RNA; STD; VRL; 1130 BP
Figure 1 - Distantly Related Rotaviruses in Common Shrews, Germany, 2004-2014 - Volume 25, Number 12-December 2019 - Emerging...
Viral Pneumonia: Practice Essentials, Background, Pathophysiology
3D Correlative Cryo-Structured Illumination Fluorescence and Soft X-ray Microscopy Elucidates Reovirus Intracellular Release...
Viral Pneumonia Imaging: Practice Essentials, Radiography, Computed Tomography
Advanced Search Results - Public Health Image Library(PHIL)
click to copy a shareable link to this record
1 Reovirus Cheat Sheet - Cheatography.com: Cheat Sheets For Every Occasion
Review on Rotavirus - Canada.ca
Virus Data | Virology | The Microbiology World | Poultrymed
Emergent Treatment of Gastroenteritis: Background, Pathophysiology, Etiology
E6 and E7 gene polymorphisms in human papillomavirus Type-6 identified in Southwest China | Virology Journal | Full Text
Bloemfontein - AbsoluteAstronomy.com
Rotavirus: Vaccine, Symptoms, Causes, Contagious, Treatment & Prevention
Rotavirus - Institute for Vaccine Safety
Viruses | Free Full-Text | Characterization of Pipistrellus pygmaeus Bat Virome from Sweden
African Horse Sickness: From a First Hand Point of View - In The Saddle
List of Descriptions sorted by Name
Viruses11
- Reoviridae is a family of viruses that can affect the gastrointestinal system (such as Rotavirus ) and respiratory tract . (wikidoc.org)
- Viruses in the family Reoviridae have genomes consisting of segmented, double-stranded RNA (dsRNA). (wikidoc.org)
- Even though viruses in the Reoviridae family have more recently been identified with various diseases, the original name is still used. (wikidoc.org)
- The genomes of viruses in Reoviridae contain 10-12 segments which are grouped into three categories corresponding to their size: L (large), M (medium) and S (small). (wikidoc.org)
- Reoviridae is a family of viruses. (fao.org)
- Sedoreoviridae (formerly Reoviridae) is a family of double-stranded RNA viruses. (wikipedia.org)
- The rotavirus is a member of the Reoviridae family of viruses and contains double-stranded RNA enclosed by a double-shelled outer layer (capsid). (medicinenet.com)
- Coltivirus is a genus of viruses that belong to the family Reoviridae. (expasy.org)
- The third of these rare viruses that we will be discussing is the Reoviridae family. (plantsentry.com)
- But the Reoviridae viruses aren't exclusive to humans. (plantsentry.com)
- Out of the abundance of Reoviridae viruses that exist, there are 3 genera that have approximately 14 different species that infect plants. (plantsentry.com)
Genus4
- Rotavirus, which is a genus within the family Reoviridae , is among the most important etiological agents of severe diarrheal illness in humans and animals around the world. (news-medical.net)
- Bluetongue (BT) is a vector-borne World Organization for Animal Health (founded as the OIE) listed disease, primarily affecting ruminants, caused by the Bluetongue virus (BTV), which belongs to the genus Orbivirus of the family Reoviridae (OIE 2019). (scielo.org.za)
- ABBR: BAV The type species of the southeast Asian genus Seadornavirus (family Reoviridae). (unboundmedicine.com)
- A genus of REOVIRIDAE , causing acute gastroenteritis in BIRDS and MAMMALS , including humans. (nih.gov)
Orbivirus1
- The virus is classified as an Orbivirus of the Reoviridae family of which there are 9 serotypes. (inthesaddle.com)
Flaviviridae1
- Examination of insect genomes has revealed endogenous viral sequences from members of the Bunyaviridae , Rhabdoviridae , Orthomyxoviridae , Reoviridae , and Flaviviridae . (virology.ws)
Family5
- Brief information on the family of virus - Reoviridae. (cheatography.com)
- Rotavirus is a very stable double-stranded RNA virus of the Reoviridae family. (vaccinesafety.edu)
- The cytoplasmic polyhedrosis virus (CPV) from the family Reoviridae belongs to a subgroup of "turreted" reoviruses, in which the mRNA capping activity occurs in a pentameric turret. (rcsb.org)
- The second genera of the Reoviridae virus family to infect plants is the Orzyavirus . (plantsentry.com)
- A novel coronavirus isolated from bats in China is unusual because the genome contains a gene from a virus in a completely different family, the Reoviridae (link to paper) . (virology.ws)
Infections1
- Below are the most recent publications written about "Reoviridae Infections" by people in Profiles. (ctsicn.org)
Proteins1
- Reoviridae proteins are denoted by the Greek character corresponding to the segment it was translated from (the L segment encodes for λ proteins, the M segment encodes for μ proteins and the S segment encodes for σ proteins). (wikidoc.org)
Genera1
- Reoviridae has 2 subfamilies that have 15 genera that divide out into a total of 75 different virus species that infect a variety of hosts, including plants and animals. (plantsentry.com)
Descriptor1
- Reoviridae" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (umassmed.edu)
Transcription1
- Their mechanism of RNA packaging, replication and transcription is similar to that of the Reoviridae of which one member, rotavirus, is a major cause of infant gastroenteritis. (cuny.edu)
Major1
- This graph shows the total number of publications written about "Reoviridae" by people in this website by year, and whether "Reoviridae" was a major or minor topic of these publications. (umassmed.edu)
Viruses14
- Reoviridae is a family of viruses. (fao.org)
- Sedoreoviridae (formerly Reoviridae) is a family of double-stranded RNA viruses. (wikipedia.org)
- Even though viruses in the family Reoviridae have more recently been identified with various diseases, the original name is still used. (wikipedia.org)
- The genomes of viruses in family Reoviridae contain 9-12 segments which are grouped into three categories corresponding to their size: L (large), M (medium) and S (small). (wikipedia.org)
- Proteins of viruses in the family Reoviridae are denoted by the Greek character corresponding to the segment it was translated from (the L segment encodes for λ proteins, the M segment encodes for μ proteins and the S segment encodes for σ proteins). (wikipedia.org)
- Viruses in the family Reoviridae have genomes consisting of segmented, double-stranded RNA (dsRNA). (wikipedia.org)
- Rotaviruses are non-enveloped viruses in the family Reoviridae, genus Rotavirus . (biomedcentral.com)
- Enteric viruses such as adenovirus-F and -G (Adenoviridae), norovirus and sapovirus (Caliciviridae), astrovirus (Astroviridae), and rotavirus (Reoviridae) are spread by fecal-oral transmission resulting in localized intestinal infections characterized by tissue inflammation, disruption of the epithelial barrier, malabsorption, diarrhea, and vomiting. (nih.gov)
- The third of these rare viruses that we will be discussing is the Reoviridae family. (plantsentry.com)
- But the Reoviridae viruses aren't exclusive to humans. (plantsentry.com)
- Out of the abundance of Reoviridae viruses that exist, there are 3 genera that have approximately 14 different species that infect plants. (plantsentry.com)
- This image shows the RNA-packaged procapsid (protein shell) of the cystovirus, the double-stranded RNA bacteriophage Phi-6, that is used as a model system for the assembly and packaging of viruses of the eukaryotes such as the Reoviridae. (nih.gov)
- We are currently working with viruses from the Reoviridae family. (tau.ac.il)
- They represent a wide-range of insect-specific viruses within the families of Bunyaviridae, Flaviviridae, Mesoniviridae, Reoviridae, Rhabdoviridae, Togaviridae, and the newly recognized taxon of Negeviruses. (utmb.edu)
Genus6
- Banna virus (BAV) is the type species of the genus Seadornavirus within the family Reoviridae. (nih.gov)
- In addition, HRLV 7 shared a close ancestral lineage with the Dinovernavirus genus of the Reoviridae family. (escholarship.org)
- African horse sickness virus (AHSV) is a member of the Orbivirus genus within the Reoviridae family and the aetiological agent for African horse sickness (AHS). (up.ac.za)
- A genus of the family REOVIRIDAE infecting vertebrates only. (musc.edu)
- A genus of REOVIRIDAE, causing acute gastroenteritis in BIRDS and MAMMALS, including humans. (wakehealth.edu)
- Bluetongue is an infectious, viral, non-contagious disease, caused by the virus of the genus Orbivirus and family Reoviridae, being transmitted by hematophagous vectors of the genus Culicoides to domestic and wild ruminants. (oalib.com)
ROTAVIRUS4
- ROTAVIRUS is an ds RNA virus ( Reoviridae ) causing severe diarrhoea ( gastroenteritis ). (rkm.com.au)
- Rotavirus is a non-enveloped virus within the Methods family of Reoviridae. (who.int)
- Rotavirus sorts into the family Reoviridae and is a double-stranded RNA virus with a segmented genome. (slu.se)
- Rotavirus from the family of Reoviridae is found world-wide and acts as the causative agent of severe diarrhoea (gastroenteritis) in almost every mammal species (especially cattle, pig, dog, cat and horse), birds and humans. (labstock.ie)
Infect1
- Reoviridae has 2 subfamilies that have 15 genera that divide out into a total of 75 different virus species that infect a variety of hosts, including plants and animals. (plantsentry.com)