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Picornain 3C
Picornain 3C () is a protease found in picornaviruses, which cleaves peptide bonds of non-terminal sequences. Picornain 3C’s endopeptidase activity is primarily responsible for the catalytic process of selectively cleaving Gln-Gly bonds in the polyprotein of poliovirus and with substitution of Glu for Gln, and Ser or Thr for Gly in other picornaviruses. Picornain 3C are cysteine proteases related by amino acid sequence to trypsin-like serine proteases. Picornain 3C is encoded by enteroviruses, rhinoviruses, Aphthovirus, aphtoviruses and cardioviruses. These genera of picoviruses cause a wide range of infections in humans and mammals. Picornavirus belongs to the family ''Picornaviridae''. Picornavirus virions are nonenveloped and the +ssRNA nonsegmented genome is encapsulated in an icosahedral protein structure made from four capsid proteins encoded by the virus. Picornavirus viral replication typically takes place in the cytoplasm of the cell. Picornavirus +ssRNA genome then gets ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribbon Diagram
Ribbon diagrams, also known as Richardson diagrams, are three-dimensional space, 3D schematic representations of protein structure and are one of the most common methods of protein depiction used today. The ribbon depicts the general course and organization of the protein backbone in 3D and serves as a visual framework for hanging details of the entire atomic structure, such as the balls for the oxygen atoms attached to myoglobin's active site in the adjacent figure. Ribbon diagrams are generated by interpolating a smooth curve through the polypeptide backbone. Alpha helix, α-helices are shown as coiled ribbons or thick tubes, Beta sheet, β-sheets as arrows, and non-repetitive coils or loops as lines or thin tubes. The direction of the Peptide, polypeptide chain is shown locally by the arrows, and may be indicated overall by a colour ramp along the length of the ribbon. Ribbon diagrams are simple yet powerful, expressing the visual basics of a molecular structure (twist, fold an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Polymerase
In molecular biology, RNA polymerase (abbreviated RNAP or RNApol), or more specifically DNA-directed/dependent RNA polymerase (DdRP), is an enzyme that catalyzes the chemical reactions that synthesize RNA from a DNA template. Using the enzyme helicase, RNAP locally opens the double-stranded DNA so that one strand of the exposed nucleotides can be used as a template for the synthesis of RNA, a process called transcription. A transcription factor and its associated transcription mediator complex must be attached to a DNA binding site called a promoter region before RNAP can initiate the DNA unwinding at that position. RNAP not only initiates RNA transcription, it also guides the nucleotides into position, facilitates attachment and elongation, has intrinsic proofreading and replacement capabilities, and termination recognition capability. In eukaryotes, RNAP can build chains as long as 2.4 million nucleotides. RNAP produces RNA that, functionally, is either for protei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis A
Hepatitis A is an infectious liver disease caused by Hepatitis A virus (HAV); it is a type of viral hepatitis. Many cases have few or no symptoms, especially in the young. The time between infection and symptoms, in those who develop them, is two to six weeks. When symptoms occur, they typically last eight weeks and may include nausea, vomiting, diarrhea, jaundice, fever, and abdominal pain. Around 10–15% of people experience a recurrence of symptoms during the six months after the initial infection. Acute liver failure may rarely occur, with this being more common in the elderly. It is usually spread by eating food or drinking water contaminated with infected feces. Undercooked or raw shellfish are relatively common sources. It may also be spread through close contact with an infectious person. While children often do not have symptoms when infected, they are still able to infect others. After a single infection, a person is immune for the rest of their life. Diagnosis req ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foot And Mouth Disease Virus
The foot (: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is an organ at the terminal part of the leg made up of one or more segments or bones, generally including claws and/or nails. Etymology The word "foot", in the sense of meaning the "terminal part of the leg of a vertebrate animal" comes from Old English ''fot'', from Proto-Germanic *''fot'' (source also of Old Frisian ''fot'', Old Saxon ''fot'', Old Norse ''fotr'', Danish ''fod'', Swedish ''fot'', Dutch ''voet'', Old High German ''fuoz'', German ''Fuß'', Gothic ''fotus'', all meaning "foot"), from PIE root *''ped-'' "foot". The plural form ''feet'' is an instance of i-mutation. Structure The human foot is a strong and complex mechanical structure containing 26 bones, 33 joints (20 of which are actively articulated), and more than a hundred muscles, tendons, and ligaments.Podiatry Channel, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhinovirus
The rhinovirus (from the "nose", , romanized: "of the nose", and the ) is a Positive-sense single stranded RNA virus, positive-sense, single-stranded RNA virus belonging to the genus ''Enterovirus'' in the family ''Picornaviridae''. Rhinovirus is the most common viral infectious agent in humans and is the predominant cause of the common cold. The three species of rhinovirus (A, B, and C) include at least 165 recognized types that differ according to their surface antigens or genetics. They are among the smallest viruses, with diameters of about 30 nanometers. By comparison, other viruses, such as smallpox and vaccinia, are around ten times larger at about 300 nanometers, while Orthomyxoviridae, influenza viruses are around 80–120 nm. Rhinoviruses are transmitted through aerosols, respiratory droplets, fomites, and direct person-to-person contact. They primarily infect nasal epithelial cells in the airway and cause mild symptoms such as sore throat, cough, and nasal con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CREB
CREB-TF (CREB, cAMP response element-binding protein) is a cellular transcription factor. It binds to certain DNA sequences called cAMP response elements (CRE), thereby increasing or decreasing the transcription of the genes. CREB was first described in 1987 as a cAMP-responsive transcription factor regulating the somatostatin gene. Genes whose transcription is regulated by CREB include: '' c-fos'', BDNF, tyrosine hydroxylase, numerous neuropeptides (such as somatostatin, enkephalin, VGF, corticotropin-releasing hormone), and genes involved in the mammalian circadian clock (PER1, PER2). CREB is closely related in structure and function to CREM ( cAMP response element modulator) and ATF-1 ( activating transcription factor-1) proteins. CREB proteins are expressed in many animals, including humans. CREB has a well-documented role in neuronal plasticity and long-term memory formation in the brain and has been shown to be integral in the formation of spatial memory. CREB down ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coxsackievirus
Coxsackieviruses are a few related enteroviruses that belong to the ''Picornaviridae'' family of viral envelope, nonenveloped, linear, positive-sense single-stranded RNA viruses, as well as its genus ''Enterovirus'', which also includes poliovirus and echovirus. Enteroviruses are among the most common and important human pathogens, and ordinarily its members are transmitted by the fecal–oral route. Coxsackieviruses share many characteristics with poliovirus. With control of poliovirus infections in much of the world, more attention has been focused on understanding the nonpolio enteroviruses such as coxsackievirus. Coxsackieviruses are among the leading causes of aseptic meningitis (the other usual suspects being echovirus and mumps virus). The entry of coxsackievirus into cells, especially endothelial cells, is mediated by coxsackievirus and adenovirus receptor. Groups Coxsackieviruses are divided into Coxsackie A virus, group A and Coxsackie B virus, group B viruses based ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EIF4E
Eukaryotic translation initiation factor 4E, also known as eIF4E, is a protein in humans encoded by the ''EIF4E'' gene. eIF4E plays a central role in translation initiation and is involved in regulating protein synthesis. Its activity influences a range of biological processes and disease states, making it an important target for therapeutic development, particularly in disorders characterized by aberrant protein production. Discovery eIF4E was discovered as a cytoplasmic cap binding protein functioning in translation by Witold Filipowicz at al. In 1976. Two years later, in 1978, Sonenberg et al. confirmed Filipowicz et al.’s findings by repeating the same experiments and adding a crosslinking chemical to increase the stability of the mRNA-protein complex. This has been confirmed by numerous scientists in their published articles such as Katherine L. B. Borden, Michael J. Osborne and Katherine L.B. Borden. Structure Most eukaryote, eukaryotic cellular Messenger RNA, mRNAs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Ribosome Entry Site
An internal ribosome entry site, abbreviated IRES, is an RNA element that allows for translation initiation in a cap-independent manner, as part of the greater process of protein synthesis. Initiation of eukaryotic translation nearly always occurs at and is dependent on the 5' cap of mRNA molecules, where the translation initiation complex forms and ribosomes engage the mRNA. IRES elements, however, allow ribosomes to engage the mRNA and begin translation independently of the 5' cap. History IRES sequences were first discovered in 1988 in the poliovirus (PV) and encephalomyocarditis virus (EMCV) RNA genomes in the laboratories of Nahum Sonenberg and Eckard Wimmer, respectively. They are described as distinct regions of RNA molecules that are able to recruit the eukaryotic ribosome to the mRNA. This process is also known as cap-independent translation. It has been shown that IRES elements have a distinct secondary or even tertiary structure, but similar structural features at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protease
A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalysis, catalyzes proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the formation of new protein products. They do this by cleaving the peptide bonds within proteins by hydrolysis, a reaction where water breaks Covalent bond, bonds. Proteases are involved in numerous biological pathways, including Digestion#Protein digestion, digestion of ingested proteins, protein catabolism (breakdown of old proteins), and cell signaling. In the absence of functional accelerants, proteolysis would be very slow, taking hundreds of years. Proteases can be found in all forms of life and viruses. They have independently convergent evolution, evolved multiple times, and different classes of protease can perform the same reaction by completely different catalytic mechanisms. Classification Based on catalytic residue Proteases can be classified into seven broad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiovirus
Cardiovirus are a group of viruses within order ''Picornavirales'', family ''Picornaviridae''. Vertebrates serve as natural hosts for these viruses. Taxonomy The genus contains the following species: * ''Cardiovirus dhusarah'' (Cardiovirus F) * ''Cardiovirus ranori'' (Cardiovirus C) * ''Cardiovirus rudhira'' (Cardiovirus E) * ''Cardiovirus rueckerti'' (Cardiovirus A), Encephalomyocarditis virus * ''Cardiovirus saffoldi'' (Cardiovirus D), Saffold virus * ''Cardiovirus theileri'' (Cardiovirus B), which contains Theiler's murine encephalomyelitis virus Structure Cardioviruses are single-stranded RNA, non-enveloped viruses with icosahedral or spherical geometries, and a T=pseudo3 icosahedral capsid protein geometry. The diameter is around 30 nm. Genomes are linear and non-segmented, around 7.8 kb in length. The T=pseudo3 icosahedral capsid of Cadiovirus is made of 60 protomers, each of which contains 4 polypeptides: VP1, VP2, VP3, and VP4. Inside the capsid of the virus th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
