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Anaphylatoxin Receptors
The anaphylatoxin receptors are a group of G-protein coupled receptors which bind anaphylatoxins. Members of this family include: * C3a receptor * C5a receptor The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G protein-coupled receptor for C5a. It functions as a complement receptor. C5a receptor modulates inflammatory responses, ob ... * C5L2 References External links * G protein-coupled receptors {{transmembranereceptor-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-protein Coupled Receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of protein family, evolutionarily-related proteins that are cell surface receptors that detect molecules outside the cell (biology), cell and activate cellular responses. Coupling with G proteins, they are called seven-transmembrane receptors because they pass through the cell membrane seven times. Text was copied from this source, which is available under Attribution 2.5 Generic (CC BY 2.5) license. Ligands can bind either to extracellular N-terminus and loops (e.g. glutamate receptors) or to the binding site within transmembrane helices (Rhodopsin-like family). They are all activated by agonists although a spontaneous auto-activation of an empty receptor can also be observed. G protein-coupled receptors are found only in eukaryotes, including y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaphylatoxin
Anaphylatoxins, or complement peptides, are fragments ( C3a, C4a and C5a) that are produced as part of the activation of the complement system. Complement components C3, C4 and C5 are large glycoproteins that have important functions in the immune response and host defense. They have a wide variety of biological activities and are proteolytically activated by cleavage at a specific site, forming a- and b-fragments. A-fragments form distinct structural domains of approximately 76 amino acids, coded for by a single exon within the complement protein gene. The C3a, C4a and C5a components are referred to as anaphylatoxins: they cause smooth muscle contraction, vasodilation, histamine release from mast cells, and enhanced vascular permeability. They also mediate chemotaxis, inflammation, and generation of cytotoxic oxygen radicals. The proteins are highly hydrophilic, with a mainly alpha-helical structure held together by 3 disulfide bridges. Function Anaphylatoxins are able to tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C3a Receptor
The C3a receptor also known as complement component 3a receptor 1 (C3AR1) is a G protein-coupled receptor protein involved in the complement system. The receptor binds to complement component C3a, although there is limited evidence that this receptor also binds C4a in lesser mammals this has yet to be proven true in humans. C3a receptor modulates immunity, arthritis, diet-induced obesity and cancers Agonists and antagonists Potent and selective agonists and antagonists An antagonist is a character in a story who is presented as the chief foe of the protagonist. Etymology The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ... for C3aR have been discovered. References Further reading * * * * * * * * * * * * * * * * * * External links * * * G protein-coupled receptors {{gene-12-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C5a Receptor
The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G protein-coupled receptor for C5a. It functions as a complement receptor. C5a receptor modulates inflammatory responses, obesity, development and cancers. Cells The C5a receptor is expressed on: *Granulocytes *Monocytes *Dendritic cells *Hepatoma-derived cell line HepG2 *Astrocytes *Microglia Agonist and antagonists Potent and selective agonist and antagonists for C5aR have been developed. See also *Complement component 5a C5a is a protein fragment released from cleavage of complement component C5 by protease C5-convertase into C5a and C5b fragments. C5b is important in late events of the complement cascade, an orderly series of reactions which coordinates several ... for binding mechanism References Further reading * * * * * * * * * * * * * * * * * * * * External links * * * * {{Complement system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C5L2
C5a anaphylatoxin chemotactic receptor 2 is a protein that in humans is encoded by the ''C5AR2'' gene. It's a complement component G protein-coupled receptor, of class A (rhodopsin-like). Function The anaphylatoxins C3a, C4a, and C5a are cationic fragments generated during the complement cascade that participate in host defense. In the case of inappropriate complement activation, anaphylatoxins may be involved in autoimmunity and sepsis. C5a2 is coexpressed with the C5a receptor, (C5a1, C5aR, C5R1, CD88), on polymorphonuclear neutrophil Neutrophils (also known as neutrocytes or heterophils) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. They form an essential part of the innate immune system, with their functions varying in ...s and may modulate C5a1 activity. References Further reading * * * * * * * * * * * External links * G protein-coupled receptors {{transmembranereceptor-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
