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NS1 Influenza Protein
The NS1 influenza protein (NS1) is a viral nonstructural protein encoded by the NS gene segments of type Influenza A virus, A, Influenza B, B and Influenza C virus, C influenza viruses. Also encoded by this segment is the nuclear export protein (NEP), formally referred to as NS2 (HCV), NS2 protein, which mediates the export of influenza virus ribonucleoprotein (RNP) complexes from the nucleus, where they are assembled.Influenza B and C Virus NEP (NS2) Proteins Possess Nuclear Export Activities Journal of Virology, August 2001, p. 7375-7383, Vol. 75, No. 16 Characteristics The NS1 of influenza A virus is a 26,000 Dalton protein. It prevents polyadenylation of cellular mRNAs to circumvent antiviral responses of the host, e ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Nonstructural Protein
In virology, a nonstructural protein is a protein encoded by a virus but that is not part of the viral particle. They typically include the various enzymes and transcription factors the virus uses to replicate itself, such as a viral protease ( 3CL/nsp5, etc.), an RNA replicase or other template-directed polymerases, and some means to control the host. Examples * NSP1 (rotavirus) * NSP4 (rotavirus) * NSP5 (rotavirus) * Influenza non-structural protein * NS1 influenza protein * HBcAg, core antigen of hepatitis B *Bunyaviridae nonstructural S proteins See also * Viral structural protein A viral structural protein is a viral protein that is a structural component of the mature virus. Examples include the SARS coronavirus 3a and 7a accessory proteins. Bacteriophage T4 structural proteins During assembly of the bacteriophage (pha ... References {{protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinase
In biochemistry, a kinase () is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule donates a phosphate group to the substrate molecule. This transesterification produces a phosphorylated substrate and ADP. Conversely, it is referred to as dephosphorylation when the phosphorylated substrate donates a phosphate group and ADP gains a phosphate group (producing a dephosphorylated substrate and the high energy molecule of ATP). These two processes, phosphorylation and dephosphorylation, occur four times during glycolysis. Kinases are part of the larger family of phosphotransferases. Kinases should not be confused with phosphorylases, which catalyze the addition of inorganic phosphate groups to an acceptor, nor with phosphatases, which remove phosphate groups (dephosphorylation). The phosphorylation state of a molecule, whet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H5N1 Genetic Structure
H5N1 genetic structure is the molecular structure of the H5N1 virus's RNA. H5N1 is an Influenza A virus subtype. Experts believe it might mutate into a form that transmits easily from person to person. If such a mutation occurs, it might remain an H5N1 subtype or could shift subtypes as did H2N2 when it evolved into the Hong Kong Flu strain of H3N2. H5N1 has mutatedFigure 1 of the article gives a diagramatic representation of the genetic relatedness of Asian H5N1 genes from various isolates of the virus. through into dozens of highly |
H5N1
Influenza A virus subtype H5N1 (A/H5N1) is a subtype of the influenza A virus which can cause illness in humans and many other animal species. A bird-adapted strain of H5N1, called HPAI A(H5N1) for highly pathogenic avian influenza virus of type A of subtype H5N1, is the highly pathogenic causative agent of H5N1 flu, commonly known as avian influenza ("bird flu"). It is enzootic (maintained in the population) in many bird populations, especially in Southeast Asia. One strain of HPAI A(H5N1) is spreading globally after first appearing in Asia. It is epizootic (an epidemic in nonhumans) and panzootic (affecting animals of many species, especially over a wide area), killing tens of millions of birds and spurring the culling of hundreds of millions of others to stem its spread. Many references to "bird flu" and H5N1 in the popular media refer to this strain. This was reprinted in 2005: According to the World Health Organization (WHO) and the United Nations Food and Agriculture O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferon-stimulated Gene
An interferon-stimulated gene (ISG) is a gene that can be expressed in response to stimulation by interferon. Interferons bind to receptors on the surface of a cell, initiating protein signaling pathways within the cell. This interaction leads to the expression of a subset of genes involved in the innate immune system response. ISGs are commonly expressed in response to viral infection, but also during bacterial infection and in the presence of parasites. Expression ISGs are genes whose expression can be stimulated by interferon, but may also be stimulated by other pathways. Interferons are a type of protein called a cytokine, which is produced in response to infection. When released, they signal to infected cells and other nearby cells that a pathogen is present. This signal is passed from one cell to another by binding of the interferon to a cell surface receptor on a naïve cell. The receptor and interferon are taken inside the cell while bound to initiate expression of ISGs. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleavage And Polyadenylation Specificity Factor
Cleavage and polyadenylation specificity factor (CPSF) is involved in the cleavage of the 3' signaling region from a newly synthesized pre-messenger RNA (pre-mRNA) molecule in the process of gene transcription. It is the first protein to bind to the signaling region near the cleavage site of the pre-mRNA, to which the poly(A) tail will be added by polynucleotide adenylyltransferase. The upstream signaling region has the canonical nucleotide sequence AAUAAA, which is highly conserved across the vast majority of pre-mRNAs. A second downstream signaling region, located on the portion of the pre-mRNA that is cleaved before polyadenylation, consists of a GU-rich region required for efficient processing. Structure CPSF is a protein complex, consisting of four proteins: CPSF-73, CPSF-100, CPSF-30 and CPSF-160. CPSF-73 is a zinc-dependent hydrolase which cleaves the mRNA precursor just downstream the polyadenylation signal sequence AAUAAA. CPSF-160 is the largest subunit of CPSF and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RIG-I
RIG-I (retinoic acid-inducible gene I) is a cytosolic pattern recognition receptor (PRR) responsible for the type-1 interferon (IFN1) response. RIG-I is an essential molecule in the innate immune system for recognizing cells that have been infected with a virus. These viruses can include West Nile virus, Japanese Encephalitis virus, influenza A, Sendai virus, flavivirus, and coronaviruses. RIG-I is structurally considered a helical ATP-dependent DExD/H box RNA helicase, that recognizes short viral double-stranded RNA (dsRNA) in the cytosol during a viral infection or other irregular RNAs (i.e., non-coding RNAs). Once activated by the dsRNA, the N-terminus caspase activation and recruitment domains (CARDs) migrate and bind with CARDs attached to mitochondrial antiviral signaling protein ( MAVS) to activate the signaling pathway for IFN1. IFN1s have three main functions: to limit the virus from spreading to nearby cells, promote an innate immune response, including inflammatory re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Terminal
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is translated from messenger RNA, it is created from N-terminus to C-terminus. The convention for writing peptide sequences is to put the C-terminal end on the right and write the sequence from N- to C-terminus. Chemistry Each amino acid has a carboxyl group and an amine group. Amino acids link to one another to form a chain by a dehydration reaction which joins the amine group of one amino acid to the carboxyl group of the next. Thus polypeptide chains have an end with an unbound carboxyl group, the C-terminus, and an end with an unbound amine group, the N-terminus. Proteins are naturally synthesized starting from the N-terminus and ending at the C-terminus. Function C-terminal retention signals While the N-terminus of a protein often conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N Terminal
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amine group is bonded to the carboxylic group of another amino acid, making it a chain. That leaves a free carboxylic group at one end of the peptide, called the C-terminus, and a free amine group on the other end called the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right (in LTR writing systems). This correlates the translation direction to the text direction, because when a protein is translated from messenger RNA, it is created from the N-terminus to the C-terminus, as amino acids are added to the carboxyl end of the protein. Chemistry Each amino acid has an amine group and a carboxylic group. Amino acids link to one another by peptide bonds which form through a dehydration reaction that jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Translation (genetics)
In molecular biology and genetics, translation is the process in which ribosomes in the cytoplasm or endoplasmic reticulum synthesize proteins after the process of transcription of DNA to RNA in the cell's nucleus. The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain, or polypeptide. The polypeptide later folds into an active protein and performs its functions in the cell. The ribosome facilitates decoding by inducing the binding of complementary tRNA anticodon sequences to mRNA codons. The tRNAs carry specific amino acids that are chained together into a polypeptide as the mRNA passes through and is "read" by the ribosome. Translation proceeds in three phases: # Initiation: The ribosome assembles around the target mRNA. The first tRNA is attached at the start codon. # Elongation: The last tRNA validated by the small ribosomal subunit (''accommodation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Kinase R
Protein kinase RNA-activated also known as protein kinase R (PKR), interferon-induced, double-stranded RNA-activated protein kinase, or eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2) is an enzyme that in humans is encoded by the ''EIF2AK2'' gene. PKR protects against viral infections. Mechanism of action Protein kinase-R is activated by double-stranded RNA (dsRNA), introduced to the cells by a viral infection. PKR can also be activated by the protein PACT or by heparin. PKR contains an N-terminal dsRNA binding domain (dsRBD) and a C-terminal kinase domain, that gives it pro-apoptotic (cell-killing) functions. The dsRBD consists of two tandem copies of a conserved double stranded RNA binding motif, dsRBM1 and dsRBM2. PKR is induced by interferon in a latent state. Binding to dsRNA is believed to activate PKR by inducing dimerization and subsequent auto-phosphorylation reactions. In situations of viral infection, the dsRNA created by viral replication and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DsRNA
Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydrates, nucleic acids constitute one of the four major macromolecules essential for all known forms of life. Like DNA, RNA is assembled as a chain of nucleotides, but unlike DNA, RNA is found in nature as a single strand folded onto itself, rather than a paired double strand. Cellular organisms use messenger RNA (''mRNA'') to convey genetic information (using the nitrogenous bases of guanine, uracil, adenine, and cytosine, denoted by the letters G, U, A, and C) that directs synthesis of specific proteins. Many viruses encode their genetic information using an RNA genome. Some RNA molecules play an active role within cells by catalyzing biological reactions, controlling gene expression, or sensing and communicating responses to cellular signa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
