| PILRB | |||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 | |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Aliases | PILRB , FDFACT1, FDFACT2, paired immunoglobin-like type 2 receptor beta, paired immunoglobin like type 2 receptor beta | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 605342 MGI: 2450532 HomoloGene: 114502 GeneCards: PILRB | ||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
| Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||
Paired immunoglobulin-like type 2 receptor beta is a protein that in humans is encoded by the PILRB gene. [5] [6]
Cell signaling pathways rely on a dynamic interaction between activating and inhibiting processes. SHP-1-mediated dephosphorylation of protein tyrosine residues is central to the regulation of several cell signaling pathways. Two types of inhibitory receptor superfamily members are immunoreceptor tyrosine-based inhibitory motif (ITIM)-bearing receptors and their non-ITIM-bearing, activating counterparts.
Control of cell signaling via SHP-1 is thought to occur through a balance between PILRalpha-mediated inhibition and PILRbeta-mediated activation. These paired immunoglobulin-like receptor genes are located in a tandem head-to-tail orientation on chromosome 7. This particular gene encodes the non-ITIM-bearing member of the receptor pair, which has a truncated cytoplasmic tail relative to its ITIM-bearing partner and functions in the activating role. Alternative splicing has been observed at this locus and three variants, encoding two distinct isoforms, are described. Additional transcript variants have been identified but their full-length nature has not been determined. [6]
The mouse homolog of PILRbeta has been studied in mice and found to have one known natural ligand, CD99, though it is unclear if this interaction occurs in the human homologs. [7]
As with other paired receptors, PILRbeta has a truncated cytoplasmic tail compared to PILRalpha and features a charged residue within its transmembrane domain. [8] [9] PILRbeta has an extracellular domain with a siglec-like immunoglobulin fold that substitutes hydrophobic interactions for the siglec fold's characteristic disulfide bond. The structure of this domain is very similar to that of PILRalpha, but the two proteins nevertheless have different binding affinities for sialic acid. [7]
Siglecs(Sialic acid-binding immunoglobulin-type lectins) are cell surface proteins that bind sialic acid. They are found primarily on the surface of immune cells and are a subset of the I-type lectins. There are 14 different mammalian Siglecs, providing an array of different functions based on cell surface receptor-ligand interactions.
CD22, or cluster of differentiation-22, is a molecule belonging to the SIGLEC family of lectins. It is found on the surface of mature B cells and to a lesser extent on some immature B cells. Generally speaking, CD22 is a regulatory molecule that prevents the overactivation of the immune system and the development of autoimmune diseases.
CD33 or Siglec-3 is a transmembrane receptor expressed on cells of myeloid lineage. It is usually considered myeloid-specific, but it can also be found on some lymphoid cells.
An immunoreceptor tyrosine-based inhibitory motif (ITIM), is a conserved sequence of amino acids that is found intracellularly in the cytoplasmic domains of many inhibitory receptors of the non-catalytic tyrosine-phosphorylated receptor family found on immune cells. These immune cells include T cells, B cells, NK cells, dendritic cells, macrophages and mast cells. ITIMs have similar structures of S/I/V/LxYxxI/V/L, where x is any amino acid, Y is a tyrosine residue that can be phosphorylated, S is the amino acid serine, I is the amino acid isoleucine, and V is the amino acid valine. ITIMs recruit SH2 domain-containing phosphatases, which inhibit cellular activation. ITIM-containing receptors often serve to target immunoreceptor tyrosine-based activation motif (ITAM)-containing receptors, resulting in an innate inhibition mechanism within cells. ITIM bearing receptors have important role in regulation of immune system allowing negative regulation at different levels of the immune response.
NKG2 also known as CD159 is a receptor for natural killer cells. There are 7 NKG2 types: A, B, C, D, E, F and H. NKG2D is an activating receptor on the NK cell surface. NKG2A dimerizes with CD94 to make an inhibitory receptor (CD94/NKG2).
Tyrosine-protein phosphatase non-receptor type 6, also known as Src homology region 2 domain-containing phosphatase-1 (SHP-1), is an enzyme that in humans is encoded by the PTPN6 gene.
Leukocyte-associated immunoglobulin-like receptor 1 is a protein that in humans is encoded by the LAIR1 gene. LAIR1 has also been designated as CD305.
Leukocyte immunoglobulin-like receptor subfamily B member 4 is a protein that in humans is encoded by the LILRB4 gene.
Sialic acid-binding Ig-like lectin 7 is a protein that in humans is encoded by the SIGLEC7 gene. SIGLEC7 has also been designated as CD328.
Sialic acid-binding Ig-like lectin 12, or Siglec-XII, is a protein that in humans, is encoded by the SIGLEC12 gene.
Leukocyte immunoglobulin-like receptor subfamily B member 3 is a protein that in humans is encoded by the LILRB3 gene.
Sialic acid-binding Ig-like lectin 9 is a protein that in humans is encoded by the SIGLEC9 gene.
Leukocyte immunoglobulin-like receptor subfamily A member 2 is a protein that in humans is encoded by the LILRA2 gene.
Sialic acid-binding Ig-like lectin 8 is a protein that in humans is encoded by the SIGLEC8 gene. This gene is located on chromosome 19q13.4, about 330 kb downstream of the SIGLEC9 gene. Within the siglec family of transmembrane proteins, Siglec-8 belongs to the CD33-related siglec subfamily, a subfamily that has undergone rapid evolution.
C-type lectin domain family 4 member A is a protein that in humans is encoded by the CLEC4A gene.
Sialic acid-binding Ig-like lectin 10 is a protein that in humans is encoded by the SIGLEC10 gene. Siglec-G is often referred to as the murine paralog of human Siglec-10
The term Kinase tyrosine-based inhibitory motif (KTIM) was coined by a group of immunology researchers from McGill University, Montreal, Quebec, Canada in 2008 to represent any immunoreceptor tyrosine-based inhibitory-like sequence motif, with the consensus sequence I/V/L/SxYxxL/V, found in a kinase and regulating its activity.
Paired immunoglobin like type 2 receptor alpha is a protein that in humans is encoded by the PILRA gene.
Paired receptors are pairs or clusters of receptor proteins that bind to extracellular ligands but have opposing activating and inhibitory signaling effects. Traditionally, paired receptors are defined as homologous pairs with similar extracellular domains and different cytoplasmic regions, whose genes are located together in the genome as part of the same gene cluster and which evolved through gene duplication. Homologous paired receptors often, but not always, have a shared ligand in common. More broadly, pairs of receptors have been identified that exhibit paired functional behavior - responding to a shared ligand with opposing intracellular signals - but are not closely homologous or co-located in the genome. Paired receptors are highly expressed in the cells of the immune system, especially natural killer (NK) and myeloid cells, and are involved in immune regulation.
Sialic acid-binding Ig-like lectin 6 is a protein that in humans is encoded by the SIGLEC6 gene. The gene was originally named CD33L (CD33-like) due to similarities between these genes but later became known as OB-BP1 due to its ability to bind to this factor and, finally, SIGLEC6 as the sixth member of the SIGLEC family of receptors to be identified. The protein has also been given the CD designation CD327.
 | This article on a gene on human chromosome 7 is a stub. You can help Wikipedia by expanding it. |
