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The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, HBEGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

Tetraspanin 7, also known as TSPAN7, is part of the transmembrane 4 superfamily, which is also familiar as the tetraspanin family. Most of these proteins mediate signal transduction events which play a role in the regulation of cell development, activation, growth as well as motility. Furthermore, TSPAN7 is associated with X-linked mental retardation in addition to neuropsychiatric diseases such as Huntington's chorea, fragile X syndrome and myotonic dystrophy. Lately, TSPAN7 has been acknowledged as a key immune system target in type 1 diabetes.

Membrane-bound & Cytosolic forms of GST are encoded by 2 separate supergene families. These enzymes function in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. There are 8 different classes of soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The GSTA1 is found in a cluster mapped to chromosome 6, and is highly expressed in the liver. GSTA1 protects the cells from reactive oxygen species.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signaling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation.
Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

C-type lectin domain family 5-member A isoform 1 (CLEC5A) is part of the CTL/CTLD superfamily which carry various functions, for instance cell-cell signaling, cell adhesion, glycoprotein turnover, in addition to their inflammation & immune response abilities. CLEC5A operates as a cell attachment receptor for all 4 serotypes of Dengue virus in addition to Japanese encephalitis virus. CLEC5A binds to the dengue virus and it triggers signaling through the phosphylation of TYROBP, as a result no viral entrance occurs, however this interaction does stimulate proinflammatory cytokine release. CLEC5A preforms as a positive regulator of osteoclastogenesis and also a main regulator of synovial injury & bone erosion for the period of autoimmune joint inflammation.

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

Thrombopoietin is a glycoprotein hormone produced mainly by the liver and the kidney which regulates the production of platelets by the bone marrow. TPO stimulates the production as well as differentiation of megakaryocytes, the bone marrow cells which fragment into large numbers of platelets.

Programmed cell death 1 ligand 2 (PDCD1LG2) which takes part in the costimulatory signal, is necessary for T-cell proliferation. PDCD1LG2 is also involved in IFNG production in a PDCD1-independent way. The interaction with PDCD1 inhibits T-cell proliferation by preventing cytokine production and cell cycle progression.

ACTA2 is a member of the actin family of proteins, an extremely conserved family of proteins which takes part in cell motility, structure and integrity. Three types of actin isoforms are known: Alpha, beta and gamma. Alpha actins are a main factor of the contractile mechanism, and beta and gamma take part in the regulation of cell motility. ACTA2 is an alpha actin which is located in skeletal muscle. Mutations in ACTA2 cause aortic aneurysm familial thoracic type 6. Various alternatively spliced variants, encoding the same protein were identified.

IL2 is a secreted cytokine that is important for the proliferation of T and B lymphocytes. The receptor of this cytokine is a heterotrimeric protein complex whose gamma chain is also shared by interleukin 4 (IL4) and interleukin 7 (IL7). The expression of this gene in mature thymocytes is monoallelic, which represents an unusual regulatory mode for controlling the precise expression of a single gene. The targeted disruption of a similar gene in mice leads to ulcerative colitis-like disease, which suggests an essential role of this gene in the immune response to antigenic stimuli.

C-type Lectin Domain Family 4, Member M (CLEC4M) is a type II integral membrane proteinand A pathogen-recognition receptor which takes part in peripheral immune surveillance in liver. CLEC4M mediates the endocytosis of pathogens which than degraded in lysosomal compartments. CLEC4M is a receptor for ICAM3, binding to mannose-like carbohydrates and also recognizes various evolutionarily divergent pathogens with a large impact on public health, including tuberculosis mycobacteria, and viruses which among them are Ebola, hepatitis C,influenza A, HIV-1, West Nile virus and the SARS-CoV acute respiratory syndrome coronavirus.

PEBP1 (Phosphatidylethanolamine binding protein 1) belongs to the phosphatidylethanolamine-binding protein family and a serine protease inhibitor that inhibits thrombin, neuropsin. PEBP1 plays a key modulatory part in several protein kinase signaling cascades. PKC phosphorylates PEBP1, resulting in the release of Raf-1 and activation of MEK and ERK. PEBP1 is expressed in many tissues and implicated in the regulation of such physiological processes as membrane biosynthesis, spermatogenesis, neural development, and metastasis suppression.
PEBP1 binds ATP, opioids and phosphatidylethanolamine, however it has lower affinity for phosphatidylinositol and phosphatidylcholine. PEBP1 may also be involved in the function of the presynaptic cholinergic neurons of the CNS. PEBP1 increases the production of choline acetyltransferase although not acetylcholinesterase. Furtheremore, PEBP1 functions in potentially sequestering toxic compounds, including locostatin which may have harmful effects on cells.
Loss of PEBP1 expression may have a significant role as prognostic marker in Gastrointestinal stromal tumors. In addition, PEBP1 is found differentially expressed in the Wernicke's Area from schizophrenia patients. PEBP1 is also, an invasion suppressor protein in nasopharyngeal carcinoma.

SNCA or Alpha-synuclein is a protein with undisclosed function that mainly concentrated in the brain tissue, mainly in the tips of the neurons in the presynaptic terminals. Almost 1% of the proteins in the brain tissues are synucleins. The protein is located mainly in the hippocampus, thalamus, cerebellum & neocortex. Smaller amounts of the SNCA protein can be found in the neuroglial cells. The MITF protein regulates the SNCA expression in melanocytic cells.

IL2 is a secreted cytokine that is important for the proliferation of T and B lymphocytes. The receptor of this cytokine is a heterotrimeric protein complex whose gamma chain is also shared by interleukin 4 (IL4) and interleukin 7 (IL7). The expression of this gene in mature thymocytes is monoallelic, which represents an unusual regulatory mode for controlling the precise expression of a single gene. The targeted disruption of a similar gene in mice leads to ulcerative colitis-like disease, which suggests an essential role of this gene in the immune response to antigenic stimuli.

Cluster of Differentiation 244 (CD244/Natural Killer Cell Receptor 2B4) contains 2 Ig-like (immunoglobulin-like) domains. CD244 is a cell surface receptor expressed on natural killer (NK) cells (and some T cells) which mediate non-major histocompatibility complex (MHC) restricted killing. NK-cell and target cells interaction via the CD244 receptor is believed to modulate NK-cell cytolytic activity. CD244 molecules function in eosinophil adhesion and chemotaxis, and have a role in the pathophysiology of allergic rhinitis (AR).

RELTis expressed in hematopoietic tissues and peripheral blood leukocytesand is a part of thetumor necrosis factor receptor superfamily. RELT mediates activation of NF-kappa-B and takes part in T-cell activation.overexpression of RELT in HEK-293 cells induces p38 and JNK signalling and leads to apoptosis. it can also costimulate T-cell proliferation in the presence of CD3 signalling.

CD48, is a GPI-linked protein which belongs to the CD2 family of immunoglobulin superfamily molecules. CD48 is capable to transduce signals and can likewise trigger signaling through CD2 or 2B4. CD48 to CD2 interactions advocate T cell activation and class replacing to IgG2a in B cells. In addition, high affinity of CD48 to 2B4, interactions may either promote or inhibit NK cell as well as cytotoxic T cell (CTL) activation. CD48 does not contain a transmembrane domain, though it is held at the cell surface by a GPI anchor through a C-terminal domain which possibly split to produce a soluble form of the receptor.

Growth-hormone-releasing hormone (GHRH), also known as growth-hormone-releasing factor (GRF or GHRF) or somatocrinin, is a 44-amino acidpeptide hormoneproduced in the arcuate nucleusof the hypothalamus.
GHRH is released from neurosecretory nerve terminals of these arcuate neurons, and is carried by the hypothalamo-hypophysial portal circulation to the anterior pituitary glandwhere it stimulates growth hormone(GH) secretion. GHRH also stimulates the production of GH. GHRH is released in a pulsatile manner, stimulating similar pulsatile release of GH. In addition, GHRH also promotes slow-wave sleepdirectly.

NIT2 is a member of the nitrilase superfamily. NIT2 protein has an omega-amidase activity which removes potentially toxic intermediates by converting alpha-ketoglutaramate and alpha-ketosuccinamate to biologically useful alpha-ketoglutarate and oxaloacetate, respectively. In addition, Nit2 is widely distributed in nature and is thought to be a tumor suppressor protein.

Interleukin 33 (IL-33) is a 32kDa proinflammatory cytokine that may also regulate gene transcription in producer cells. IL-33 is structurally related to IL-1, which induces helper T cells to produce type 2 cytokines and acts through the receptor IL1RL-1 (IL1 receptor-like-1), which is known also as ST2. Binding of IL-33 to this receptor activates NF-kappa-B and MAP kinases and induces in vitro Th2 cells to produce cytokines. In vivo, IL-33 induces expression of IL-4, IL-5, IL-13 and leads to severe pathological changes in mucosal organs and in vitro, it can be divided to N-terminal fragment of 12kDa and C-terminal fragment of 18kDa by cleavage of caspase-1.

HSPB11 is a component of IFT complex B composed of IFT88, IFT57, TRAF3IP1, IFT52, IFT27, HSPB11 and IFT20. HSPB11 is detected in the placenta.

Murine IL-36a belongs to the IL-1 family that includes IL-1b, IL-1a, IL-1ra, IL-18, IL-36ra (IL1F5), IL-36b (IL1F8), IL-36g (IL1F9), IL-37 (IL1F7) and IL-38 (IL-1F10). The IL-1 family members display a 12 b-strand, b-trefoil configuration, and are thought to have ascended from a mutual ancestral gene. Murine IL-36a is a 160 amino acid intracellular and secreted protein which holds no signal sequence, no prosegment and no potential N-linked glycosylation sites. IL-36a is released as a reaction to LPS and the cell ATP-induced activation of the P2X7 receptor.
Mouse to human, full length IL-36a/IL-1F6 shares 54% aa sequence homology. IL-36a is mostly found in skin and lymphoid tissues, but also in fetal brain, trachea, stomach and intestine.

NHP2 belongs to the H/ACA snoRNPs (small nucleolar ribonucleoproteins) gene family. snoRNPs are involved in various aspects of rRNA processing and modification and have been organized into 2 families: C/D and H/ACA. NHP2 (NOLA2) forms a small ribonucleoprotein particle with GAR1 (NOLA1), Nop10 for the isomerization of uridine to pseudouridine. NHP2 is involved in a variety of aspects of rRNA processing and modification. NHP2 localizes to the dense fibrillar component of the nucleolus and in nuclear Cajal bodies.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells. The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes. The KIR proteins are categorized 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). Whereas 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. KIR2DL3 is an inhibitory Killer Cell Ig-like Receptor (KIR, previously called p58 KIR, cl-6, NKAT2 or KIR-K7), which recognizes class I MHC molecules (HLA-Cw1, -Cw3, -Cw7, and Cw8). KIR2DL3 inhibits the activity of NK cells thus preventing cell lysis.