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Hepatitis C Virus Stem-loop VII
Hepatitis C virus stem-loop VII is a Cis-regulatory element, regulatory element found in the coding region of the RNA-dependent RNA polymerase gene, NS5B. Similarly to Hepatitis C stem-loop IV, stem-loop IV, the stem-loop structure is important (but not essential) for colony formation, though its exact function and mechanism are unknown. See also * Hepatitis C alternative reading frame stem-loop * Hepatitis C virus (HCV) cis-acting replication element (CRE) * Hepatitis C virus 3'X element References External links * Cis-regulatory RNA elements Hepatitis C virus {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Structure
Protein secondary structure is the three dimensional conformational isomerism, form of ''local segments'' of proteins. The two most common Protein structure#Secondary structure, secondary structural elements are alpha helix, alpha helices and beta sheets, though beta turns and omega loops occur as well. Secondary structure elements typically spontaneously form as an intermediate before the protein protein folding, folds into its three dimensional protein tertiary structure, tertiary structure. Secondary structure is formally defined by the pattern of hydrogen bonds between the Amine, amino hydrogen and carboxyl oxygen atoms in the peptide backbone chain, backbone. Secondary structure may alternatively be defined based on the regular pattern of backbone Dihedral angle#Dihedral angles of proteins, dihedral angles in a particular region of the Ramachandran plot regardless of whether it has the correct hydrogen bonds. The concept of secondary structure was first introduced by Kaj Ulrik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequence Conservation
In evolutionary biology, conserved sequences are identical or similar sequences in nucleic acids ( DNA and RNA) or proteins across species ( orthologous sequences), or within a genome ( paralogous sequences), or between donor and receptor taxa ( xenologous sequences). Conservation indicates that a sequence has been maintained by natural selection. A highly conserved sequence is one that has remained relatively unchanged far back up the phylogenetic tree, and hence far back in geological time. Examples of highly conserved sequences include the RNA components of ribosomes present in all domains of life, the homeobox sequences widespread amongst Eukaryotes, and the tmRNA in Bacteria. The study of sequence conservation overlaps with the fields of genomics, proteomics, evolutionary biology, phylogenetics, bioinformatics and mathematics. History The discovery of the role of DNA in heredity, and observations by Frederick Sanger of variation between animal insulins in 1949, promp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-regulatory Element
''Cis''-regulatory elements (CREs) or ''Cis''-regulatory modules (CRMs) are regions of non-coding DNA which regulate the transcription of neighboring genes. CREs are vital components of genetic regulatory networks, which in turn control morphogenesis, the development of anatomy, and other aspects of embryonic development, studied in evolutionary developmental biology. CREs are found in the vicinity of the genes that they regulate. CREs typically regulate gene transcription by binding to transcription factors. A single transcription factor may bind to many CREs, and hence control the expression of many genes ( pleiotropy). The Latin prefix ''cis'' means "on this side", i.e. on the same molecule of DNA as the gene(s) to be transcribed. CRMs are stretches of DNA, usually 100–1000 DNA base pairs in length, where a number of transcription factors can bind and regulate expression of nearby genes and regulate their transcription rates. They are labeled as ''cis'' because they are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisting of (i) the genetic material, i. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA-dependent RNA Polymerase
RNA-dependent RNA polymerase (RdRp) or RNA replicase is an enzyme that catalyzes the replication of RNA from an RNA template. Specifically, it catalyzes synthesis of the RNA strand complementary to a given RNA template. This is in contrast to typical DNA-dependent RNA polymerases, which all organisms use to catalyze the transcription of RNA from a DNA template. RdRp is an essential protein encoded in the genomes of most RNA-containing viruses with no DNA stage including SARS-CoV-2. Some eukaryotes also contain RdRps, which are involved in RNA interference and differ structurally from viral RdRps. History Viral RdRps were discovered in the early 1960s from studies on mengovirus and polio virus when it was observed that these viruses were not sensitive to actinomycin D, a drug that inhibits cellular DNA-directed RNA synthesis. This lack of sensitivity suggested that there is a virus-specific enzyme that could copy RNA from an RNA template and not from a DNA template. Distr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NS5B
Nonstructural protein 5B (NS5B) is a viral protein found in the hepatitis C virus (HCV). It is an RNA-dependent RNA polymerase, having the key function of replicating HCV's viral RNA by using the viral positive RNA strand as a template to catalyze the polymerization of ribonucleoside triphosphates (rNTP) during RNA replication. Several crystal structures of NS5B polymerase in several crystalline forms have been determined based on the same consensus sequence BK (HCV-BK, genotype 1). The structure can be represented by a right hand shape with fingers, palm, and thumb. The encircled active site, unique to NS5B, is contained within the palm structure of the protein. Recent studies on NS5B protein genotype 1b strain J4's (HC-J4) structure indicate a presence of an active site where possible control of nucleotide binding occurs and initiation of de-novo RNA synthesis. De-novo adds necessary primers for initiation of RNA replication. Drugs targeting NS5B Several drugs are either on the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis C Stem-loop IV
The Hepatitis C stem-loop IV is part of a putative cis-regulatory element, RNA element found in the NS5B coding region. This element along with Hepatitis C virus stem-loop VII, stem-loop VII, is important (but not essential) for colony formation, though its exact function and mechanism are unknown. See also * Hepatitis C alternative reading frame stem-loop * Hepatitis C virus (HCV) cis-acting replication element (CRE) * Hepatitis C virus 3'X element * Hepatitis E virus cis-reactive element References External links * Cis-regulatory RNA elements Hepatitis C virus {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stem-loop
Stem-loop intramolecular base pairing is a pattern that can occur in single-stranded RNA. The structure is also known as a hairpin or hairpin loop. It occurs when two regions of the same strand, usually complementary in nucleotide sequence when read in opposite directions, base-pair to form a double helix that ends in an unpaired loop. The resulting structure is a key building block of many RNA secondary structures. As an important secondary structure of RNA, it can direct RNA folding, protect structural stability for messenger RNA (mRNA), provide recognition sites for RNA binding proteins, and serve as a substrate for enzymatic reactions. Formation and stability The formation of a stem-loop structure is dependent on the stability of the resulting helix and loop regions. The first prerequisite is the presence of a sequence that can fold back on itself to form a paired double helix. The stability of this helix is determined by its length, the number of mismatches or bulges it co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis C Alternative Reading Frame Stem-loop
Hepatitis C alternative reading frame stem-loop is a conserved secondary structure motif identified in the RNA genome of the Hepatitis C virus (HCV) which is proposed to have an important role in regulating Translation (biology), translation and repression of the viral genome. The core protein-coding region of the Hepatitis C virus (HCV) genome contains a +1 alternative reading frame (ARF) and two proposed phylogenetically conserved RNA helix-forming stem loop structures (Hepatitis C stem-loop IV, IV and Hepatitis C virus stem-loop VII, VII). The proteins translated from the ARF appear to be translated during the normal viral life cycle but are not essential to virus replication. The two predicted stem loops shown here (SLV and SLVI) are proposed to be important for HCV translation and repression; these stem loops are located downstream of the Internal ribosome entry site (IRES) but their functional role is unknown. See also *Hepatitis E virus cis-reactive element References E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis C Virus (HCV) Cis-acting Replication Element (CRE)
The Hepatitis C virus (HCV) cis-acting replication element (CRE) is an RNA element which is found in the coding region of the RNA-dependent RNA polymerase NS5B. Mutations in this family have been found to cause a blockage in RNA replication and it is thought that both the primary sequence and the structure of this element are crucial for HCV RNA replication. See also * Hepatitis C alternative reading frame stem-loop * Hepatitis C virus 3'X element * Hepatitis C virus stem-loop VII * Hepatitis C stem-loop IV * Hepatitis C Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver; it is a type of viral hepatitis. During the initial infection people often have mild or no symptoms. Occasionally a fever, dark urine, a ... References External links * Cis-regulatory RNA elements Hepatitis C virus {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis C Virus 3'X Element
The hepatitis C virus 3′X element is an RNA element which contains three stem-loop structures that are essential for replication. See also * Hepatitis C alternative reading frame stem-loop * Hepatitis C stem-loop IV * Hepatitis C virus stem-loop VII Hepatitis C virus stem-loop VII is a Cis-regulatory element, regulatory element found in the coding region of the RNA-dependent RNA polymerase gene, NS5B. Similarly to Hepatitis C stem-loop IV, stem-loop IV, the stem-loop structure is important (b ... * Hepatitis C virus (HCV) cis-acting replication element (CRE) References External links * {{molecular-cell-biology-stub Cis-regulatory RNA elements Hepatitis C virus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-regulatory RNA Elements
''Cis-acting replication elements'' bring together the 5′ and 3′ ends during replication of positive-sense single-stranded RNA viruses (for example Picornavirus, Flavivirus, coronavirus, togaviruses, Hepatitis C virus) and double-stranded RNA viruses (for example rotavirus and reovirus). See also *Cis-regulatory element *List of cis-regulatory RNA elements *Enterovirus cis-acting replication element and Enterovirus 5′ cloverleaf cis-acting replication element *Cardiovirus cis-acting replication element (CRE) *Coronavirus SL-III cis-acting replication element (CRE) *Rotavirus cis-acting replication element *Hepatitis C virus cis-acting replication element *Flavivirus 3′ UTR cis-acting replication element (CRE) *Potato virus X cis-acting regulatory element *Human rhinovirus internal cis-acting regulatory element (CRE) Human rhinovirus internal cis-acting regulatory element (CRE) is a CRE from the human rhinoviruses. The CRE is located within the genome segment encoding the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
