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Class II Cytokine Receptor
Type II cytokine receptors, also commonly known as class II cytokine receptors, are transmembrane proteins that are expressed on the surface of certain cells. They bind and respond to a select group of cytokines including interferon type I, interferon type II, interferon type III. and members of the interleukin-10 family These receptors are characterized by the lack of a WSXWS motif which differentiates them from type I cytokine receptors. Structure Typically type II cytokine receptors are heterodimers or multimers with a high and a low affinity component. These receptors are related predominantly by sequence similarities in their extracellular portions that are composed of tandem Ig-like domains. The structures for the extracellular domains of the receptors for interferon types, I, II, and III are all known. Type II cytokine receptors are tyrosine-kinase-linked receptors. The intracellular domain of type II cytokine receptors is typically associated with a tyrosine kinas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmembrane
A transmembrane protein is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequently undergo significant conformational changes to move a substance through the membrane. They are usually highly hydrophobic and aggregate and precipitate in water. They require detergents or nonpolar solvents for extraction, although some of them ( beta-barrels) can be also extracted using denaturing agents. The peptide sequence that spans the membrane, or the transmembrane segment, is largely hydrophobic and can be visualized using the hydropathy plot. Depending on the number of transmembrane segments, transmembrane proteins can be classified as single-pass membrane proteins, or as multipass membrane proteins. Some other integral membrane proteins are called monotopic, meaning that they are also permanently attached to the membrane, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferon
Interferons (IFNs, ) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses. IFNs belong to the large class of proteins known as cytokines, molecules used for communication between cells to trigger the protective defenses of the immune system that help eradicate pathogens. Interferons are named for their ability to "interfere" with viral replication by protecting cells from virus infections. However, virus-encoded genetic elements have the ability to antagonize the IFN response, contributing to viral pathogenesis and viral diseases. IFNs also have various other functions: they activate immune cells, such as natural killer cells and macrophages, and they increase host defenses by up-regulating antigen presentation by virtue of increasing the expression of major histocompatibility compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-22 Receptor
Interleukin-22 receptor is a type II cytokine receptor Type II cytokine receptors, also commonly known as class II cytokine receptors, are transmembrane proteins that are expressed on the surface of certain cells. They bind and respond to a select group of cytokines including interferon type I, i .... It binds to Interleukin-22. It is a heterodimer of α1 and IL-10Rβ2 subunits. References External links * Type II cytokine receptors {{membrane-protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-20 Receptor
Interleukin 20 receptors (IL20R) belong to the IL-10 family. IL20R are involved in both pro-inflammatory and anti-inflammatory immune response. There are two types of IL20R: Type I and Type II. IL20R is found in many organ resident effector cells such as keratinocytes at the skin epidermis, osteoclasts, found in bones, and epithelial cells of the intestine and trachea. IL20R alpha and beta subunits have also been found in some immune cells. IL20R is implicated in diseases such as psoriasis, rheumatoid arthritis, and glaucoma. Structure and function There are two types of IL20R: Type I, made up of the IL-20 receptor alpha subunit and beta subunit, and Type II, made up of the IL-22 receptor and IL-20 receptor beta subunit. Both types of receptor bind the cytokines IL-20, IL-24. Type 1 also binds cytokine IL-19. Signaling IL20R signalling happens through the JAK-STAT pathway. When an IL-20 subfamily cytokine binds IL20R, JAK's linked to intracellular domains of IL20R a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-10 Receptor
Interleukin-10 receptor (IL-10R) is a type II cytokine receptor. The receptor is tetrameric, composed of 2 α and 2 β subunits. The α subunit (encoded in the ''Il10ra gene)'' is expressed on haematopoietic cells (such as T, B, NK, mast, and dendritic cells) whilst the β subunit (encoded in the ''Il10rb gene'') is expressed ubiquitously. The α subunit is exclusive to interleukin-10, however the β subunit is shared with other type II cytokine receptors such as IL-22R, IL-26R and INFλR. The IL-10R α subunit acts as the ligand binding site and may be upregulated in various cell types as necessary. The IL-10R β functions as the signaling subunit and is constitutively expressed in a majority of cell types. There is evidence that upon ligand binding at the α subunit, a conformational change occurs in the β subunit that allows it to additionally bind to IL-10. This structure forms a heterotetramer that leads to the signaling complex activation of JAK1 and TYK2 kinase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferon Type III
The type III interferon group is a group of anti-viral cytokines, that consists of four IFN-λ (lambda) molecules called IFN-λ1, IFN-λ2, IFN-λ3 (also known as IL29, IL28A and IL28B respectively), and IFN-λ4. They were discovered in 2003. Their function is similar to that of type I interferons, but is less intense and serves mostly as a first-line defense against viruses in the epithelium. Genomic location Genes encoding this group of interferons are all located on the long arm of chromosome 19 in human, specifically in region between 19q13.12 and 19q13.13. The ''IFNL1'' gene, encoding IL-29, is located downstream of ''IFNL2'', encoding IL-28A. ''IFNL3'', encoding IL28B, is located downstream of IFNL4. In mice, the genes encoding for type III interferons are located on chromosome 7 and the family consists only of IFN-λ2 and IFN-λ3. Structure Interferons All interferon groups belong to class II cytokine family which have a conserved structure that comprises six α-hel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferon-gamma Receptor
The interferon-gamma receptor (IFNGR) protein complex is the heterodimer of two chains: interferon gamma receptor 1, IFNGR1 and interferon gamma receptor 2, IFNGR2. It binds Interferon-gamma, interferon-γ, the sole member of interferon type II. Structure and function The human interferon-gamma receptor complex consists the heterodimer of two chains: interferon gamma receptor 1, IFNGR1 and interferon gamma receptor 2, IFNGR2. In unstimulated cells, these subunits are not preassociated with each other but rather associate through their intracellular domains with inactive forms of specific Janus family kinases (Jak1 and Jak2). Jak1 and Jak2 constitutively associate with IFNGR1 and IFNGR2, respectively. Binding of IFN-γ to IFNGR1 induces the rapid dimerization of IFNGR1 chains, thereby forming a site that is recognized by the extracellular domain of IFNGR2. The ligand-induced assembly of the complete receptor complex contains two IFNGR1 and two IFNGR2 subunits, which bring int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferon-alpha/beta Receptor
The interferon-α/β receptor (IFNAR) is a virtually ubiquitous membrane receptor which binds endogenous type I interferon (IFN) cytokines. Endogenous human type I IFNs include many subtypes, such as interferons-α, -β, -ε, -κ, -ω, and -ζ. Function Activation of various innate immune signaling pathways ( TLR3, TLR4, TLR7, TLR8, TLR9, cGAS, RIG-I, MDA-5) leads to the rapid induction of type I IFNs due to their (mostly) intronless gene structure. The regulatory elements upstream of type I IFN genes differ, allowing differential transcription of type I IFNs in response to stimuli. In particular, IFNβ contains a κB regulatory site, whereas IFNα subtypes do not. Production of specific type I IFNs is usually limited to a small number of type I IFN subtypes. Once secreted, type I IFNs signal through IFNAR in a paracrine and autocrine manner. IFNAR is a heteromeric cell surface receptor composed of two subunits, referred to as the low affinity subunit, IFNAR1, and the hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regulation Of Gene Expression
Regulation of gene expression, or gene regulation, includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products (protein or RNA). Sophisticated programs of gene expression are widely observed in biology, for example to trigger developmental pathways, respond to environmental stimuli, or adapt to new food sources. Virtually any step of gene expression can be modulated, from Transcriptional regulation, transcriptional initiation, to RNA processing, and to the post-translational modification of a protein. Often, one gene regulator controls another, and so on, in a gene regulatory network. Gene regulation is essential for viruses, prokaryotes and eukaryotes as it increases the versatility and adaptability of an organism by allowing the cell to express protein when needed. Although as early as 1951, Barbara McClintock showed interaction between two genetic loci, Activator (''Ac'') and Dissociator (''Ds''), in the color f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epithelial Cells
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of many internal organs, the corresponding inner surfaces of body cavities, and the inner surfaces of blood vessels. Epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. These tissues also lack blood or lymph supply. The tissue is supplied by nerves. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. These can be arranged in a singular layer of cells as simple epithelium, either simple squamous, simple columnar, or simple cuboidal, or in layers of two or more cells deep as stratified (layered), or ''compound'', either squamous, columnar or cuboidal. In some tissues, a layer of columnar cells may appear to be stratified due ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin 28
Interleukin-28 (IL-28) is a cytokine that comes in two isoforms, IL-28A and IL-28B, and plays a role in immune defense against viruses, including the induction of an "antiviral state" by turning on Mx proteins, 2',5'-oligoadenylate synthetase as well as ISGF3G (Interferon Stimulated Gene Factor 3). IL-28A and IL-28B belong to the type III interferon family of cytokines and are highly similar (in amino acid sequence) to IL-29. Their classification as Interferons is due to their ability to induce an antiviral state, while their additional classification as cytokines is due to their chromosomal location as well as the fact that they are encoded by multiple exons, as opposed to a single exon, as most type-I IFNs are. Discovery IL-28 was discovered in 2002 by Zymogenetics using a genomic screening process in which the entire human genome was scanned for putative genes. Once these genes were found, a second scan was performed to look specifically for cytokines. Both IL-28 and IL ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interleukin-22
Interleukin-22 (IL-22) is a protein that in humans is encoded by the ''IL22'' gene. Structure IL-22 is an α-helical cytokine. IL-22 binds to a heterodimeric cell surface receptor composed of IL-10R2 and IL-22R1 subunits. IL-22R is expressed on tissue cells, and it is absent on immune cells. Crystallization is possible if the N-linked glycosylation sites are removed in mutants of IL-22 bound with high-affinity cell-surface receptor sIL-22R1. The crystallographic asymmetric unit contained two IL-22-sIL-22R1 complexes. Function IL-22 is produced by several populations of immune cells at a site of inflammation. Producers are αβ T-cell classes Th1, Th22 and Th17 along with γδ T cells, NKT, ILC3, neutrophils and macrophages. IL-22 takes effect on non-hematopoietic cells – mainly stromal and epithelial cells. Effects involve stimulation of cell survival, proliferation and synthesis of antimicrobials including S100, Reg3β, Reg3γ and defensins. IL-22 thus participa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
