| Primary Identifier | IPR027669 | Type | Family |
| Short Name | P2Y8_rcpt |
| description | This entry represents the P2Y8 receptor. It was originally identified in Xenopus and found to be activated equipotently by all naturally occurring nucleoside triphosphates (ATP, CTP, GTP, ITP and UTP) but not by inorganic polyphosphates [].P2RY8 is a G protein-coupled receptor for S-geranylgeranyl-glutathione (GGG), an endogenous metabolite present in lymphoid tissues. It couples the binding of GGG to the activation of GNA13 and downstream repression of AKT activation in lymphocytes defining their positioning and growth within lymphoid organs [, , ]. In lymphoid follicles, confines B cells and follicular helper T cells in germinal centers (GCs) in response to GGG local gradients established by GGT5 (via GGG catabolism) and ABCC1 (via extracellular transport) with lower concentrations of GGG found in the follicular dendritic cell network region around which germinal centers are formed [, , ]. In the bone marrow, also in response to GGG gradients established by GGT5 and ABCC1, it restricts chemotactic transmigration of B cells, T cells and NK cells from blood vessels to the bone marrow parenchyma [, ].There are three distinct families of extracellular receptors for purine and pyrimidine nucleotides [], known as P1, P2X and P2Y purinoceptors []. These receptors induce a wide variety of biological effects and are involved in many different cellular functions [, , ]. P2X receptors are ligand-gated ion channels, whereas P1 and P2Y receptors are rhodopsin-like G protein-coupled receptors [, ]. The families also differ by their method of activation: P1 receptors are preferentially activated by adenosine [], P2X via ATP [], whereas the P2Y receptors, in addition to being activated by ATP, are activated by different adenine and/or uridine nucleoside di- and triphosphates (ADP, UDP, UTP, UDP and UDP-glucose) [].The P2Y purinoceptors currently consist of eleven subtypes: P2Y1, P2Y2, P2Y3 P2Y4, P2Y6, P2Y8, P2Y10, P2Y11, P2Y12, P2Y13 and P2Y14 [, , ]. P2Y3 has, as yet, only been found in birds [], whilst the rest have been cloned in humans. The gaps in P2Y receptor numbering are due to the reclassification of some receptors that were initially associated with to the P2Y family. These include P2Y5 (now known as lysophosphatidic acid receptor 6), P2Y7 (now leukotriene B4 receptor) and P2Y9 (lysophosphatidic acid receptor 4) [, , , ]. |
