Killer cell immunoglobulin-like receptor 2DL1 is a protein that in humans is encoded by the KIR2DL1 gene. [3] [4] [5]
Killer-cell immunoglobulin-like receptors (KIRs) are transmembrane glycoproteins expressed by natural killer cells and subsets of T cells. The KIR genes are polymorphic and highly homologous and they are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). The gene content of the KIR gene cluster varies among haplotypes, although several "framework" genes are found in all haplotypes (KIR3DL3, KIR3DP1, KIR2DL4, KIR3DL2). The KIR proteins are classified by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM), while KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. The ligands for several KIR proteins are subsets of HLA class I molecules; thus, KIR proteins are thought to play an important role in regulation of the immune response. [5]
KIR2DL1 has been shown to interact with HLA-C. [6] [7] [8] [9]
In immunology, an immunological synapse is the interface between an antigen-presenting cell or target cell and a lymphocyte such as a T/B cell or Natural Killer cell. The interface was originally named after the neuronal synapse, with which it shares the main structural pattern. An immunological synapse consists of molecules involved in T cell activation, which compose typical patterns—activation clusters. Immunological synapses are the subject of much ongoing research.
HLA-C belongs to the MHC class I heavy chain receptors. The C receptor is a heterodimer consisting of a HLA-C mature gene product and β2-microglobulin. The mature C chain is anchored in the membrane. MHC Class I molecules, like HLA-C, are expressed in nearly all cells, and present small peptides to the immune system which surveys for non-self peptides.
Killer-cell immunoglobulin-like receptors (KIRs), are a family of type I transmembrane glycoproteins expressed on the plasma membrane of natural killer (NK) cells and a minority of T cells. At least 15 genes and 2 pseudogenes encoding KIR map in a 150-kb region of the leukocyte receptor complex (LRC) on human chromosome 19q13.4.
CD94, also known as killer cell lectin-like receptor subfamily D, member 1 (KLRD1) is a human gene.
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.
Leukocyte immunoglobulin-like receptor subfamily B member 1 is a protein that in humans is encoded by the LILRB1 gene.
Killer cell immunoglobulin-like receptor 3DL1 is a protein that in humans is encoded by the KIR3DL1 gene.
Killer cell immunoglobulin-like receptor 2DL4 is a protein that in humans is encoded by the KIR2DL4 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 2 is a protein that in humans is encoded by the LILRB2 gene.
Killer cell immunoglobulin-like receptor 3DL2 is a protein that in humans is encoded by the KIR3DL2 gene.
Killer cell immunoglobulin-like receptor 2DS4 is a protein that in humans is encoded by the KIR2DS4 gene.
NKG2-C type II integral membrane protein or NKG2C is a protein that in humans is encoded by the KLRC2 gene. It is also known as or cluster of differentiation 159c (CD159c).
Leukocyte immunoglobulin-like receptor subfamily A member 2 is a protein that in humans is encoded by the LILRA2 gene.
Leukocyte-associated immunoglobulin-like receptor 2 is a protein that in humans is encoded by the LAIR2 gene.
Killer cell immunoglobulin-like receptor 3DL3 is a protein that in humans is encoded by the KIR3DL3 gene.
Killer Activation Receptors (KARs) are receptors expressed on the plasmatic membrane of Natural Killer cells. KARs work together with inhibitory receptors, which inactivate them in order to regulate the NK cells functions on hosted or transformed cells. These two kinds of specific receptors have some morphological features in common, such as being transmembrane proteins. The similarities are specially found in the extracellular domains and, the differences tend to be in the intracellular domains. KARs and KIRs can have tyrosine containing activatory or inhibitory motifs in the intracellular part of the receptor molecule.
Killer cell immunoglobulin-like receptor, two domains, short cytoplasmic tail, 1 is a protein that in humans is encoded by the KIR2DS1 gene.
KIR2DL3, Killer cell immunoglobulin-like receptor 2DL3 is a transmembrane glycoprotein expressed by the natural killer cells and the subsets of the T cells. The KIR genes are polymorphic, which means that they have many different alleles. The KIR genes are also extremely homologous, which means that they are similar in position, structure and evolutionary origin, but not necessarily in function.
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.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.