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A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

BAG3 Inhibits the chaperone activity of HSP70/HSC70 by promoting substrate release. BAG3 has anti-apoptotic activity. BAG proteins participate with Hip for their binding to Hsc70/Hsp70 ATPase domain and encourage substrate release. BAG proteins have about 45 amino acid BAG domain close to the C terminus however they differ noticeably in their N-terminal regions. BAG3 includes a WW domain in the N-terminal region and a BAG domain in the C-terminal region. The BAG domains of BAG1, BAG2, and BAG3 interact particularly with the Hsc70 ATPase domain in vitro and in mammalian cells. They bind with high affinity to the ATPase domain of Hsc70 and inhibit its chaperone activity in a Hip-repressible manner. BAG3 plays a role as a protein-refolding cochaperone of the bcl2 binding protein BAG family and as upregulated in response to persistent stress of cellular calcium balance dysregulation. BAG3 has been shown to diminish stress-induced apoptosis.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

Myelin Protein Zero-Like 1 (MPZL1) is a cell surface receptor, which is involved in signal transduction processes. MPZL1 recruits PTPN11/SHP-2 to the cell membrane and is a putative substrate of PTPN11/SHP-2. MPZL1 is a main receptor for concanavalin-A (ConA) and it is involved in cellular signaling induced by ConA, which most likely includes Src family tyrosine-protein kinases. MPZL1 Isoform 3 appears to have a dominant negative role by blocking tyrosine phosphorylation of MPZL1 induced by ConA. Isoform 1, but not isoform 2 and isoform 3, might be involved in regulation of integrin-mediated cell motility.

Anti-Mullerian Hormone also known as AMH is a member of the TGF-beta family. AMH is a glycoprotein which is produced by the Sertoli cells of the testis, causes regression of the Muellerian duct. AMH inhibits the growth of tumors derived from tissues of Muellerian duct origin. Moreover, AMH participates in Leydig cell differentiation and function in addition to follicular development in adult females.

ANGPTL3 and ANGPTL4 are angiopoietin-like proteins secreted and expressed mainly by the liver, their role being the regulation of triglyceride metabolism by inhibiting the lipolysis of triglyceride-rich lipoproteins. During different nutritional states (feeding/fasting) the levels of the circulating triglycerides are regulated by Angptl3 and Angptl4 through differential inhibition of Lipoprotein lipase (LPL) as shown by the experimental data. The molecular structure of ANGPTL3 is similar to that of the angiopoietins (vascular endothelial growth factors). Deletion mutants of human Angiopoietin 5 were used in order to demonstrate that the N-terminal domain (fragment 17-207) and not the C-terminal fibrinogen-like domain (fragment 207-460) increased the plasma triglyceride levels in mice.

Anthrax toxin receptor 2, also known as ANTXR2, takes part in the configuration of little blood vessels (capillaries). ANTXR2 helps the toxin that leads to anthrax to attach to cells and trigger illness. ANTXR2 is necessary for cellular interactions with laminin and the extracellular matrix.

NCALD belongs to the neuronal calcium sensor (NCS) family. NCALD is cytosolic at inactive calcium levels; but, high intracellular calcium levels induce a conformational transformation which exposes the myristoyl group, causing protein association with membranes and partial co-localization with the perinuclear trans-golgi network. NCALD protein is a regulator of signal transduction by G protein-coupled receptor.

Norrie Disease (NDP) is a secreted regulatory protein which activates the canonical Wnt signaling pathway through FZD4 and LRP5 coreceptor. NDP takes part in retinal vascularization by acting as a ligand for FZD4 which signals through stabilizing beta-catenin (CTNNB1) and activating LEF/TCF-mediated transcriptional programs. NDP is involved in a pathway that regulates neural cell differentiation and proliferation and also in neuroectodermal cell-cell interaction.

OAZ1 is a member of the ODC antizyme family. OAZ1 is auto-regulated expressed by polyamine-enhanced translational frame shifting. OAZ1 negatively controls polyamine synthesis by increasing the negative feedback loop regulating ornithine decarboxylase (ODC) activity. The OAZ1 protein inhibits ornithine decarboxylase and speeds up its detraction.

Truncated BH3 interacting domain death agonist is a truncated form of the pro-apoptotic full-length BID. Truncated BH3 interacting domain death agonist is generated by Caspase-8 cleavage of BID. The truncated form of the protein translocates from the cytosol to mitochondria and transduces apoptotic signals.
BID is a pro-apoptotic Bcl-2 protein having only the BH3 domain. In reaction to apoptotic signaling, BID interacts with another Bcl-2 family of cell death regulators, called Bax, they form a heterodimer resulting to the insertion of Bax into the outer mitochondrial membrane. Bax induces the opening of the mitochondrial voltage-dependent anion channel which lead to the release of cytochrome c and other pro-apoptotic factors from the mitochondria resulting in activation of caspases. BID is a mediator of mitochondrial damage induced by caspase-8 (CASP8). CASP8 cleaves BID, and the COOH-terminal part translocates to mitochondria where it triggers cytochrome c release. The major proteolytic product p15 BID releasea cytochrome c. Isoform 1, Isoform 2 and Isoform 4 induce ice-like proteases and apoptosis while Isoform 3 does not induce apoptosis.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Calcium-activated nucleotidase 1 (CANT1) is a member of the apyrase family. The CANT1 protein is calcium-dependent nucleotidase with a preference for UDP. The order of activity with different substrates is as follows: UDP > GDP > UTP > GTP. Moreover, CANT1 has a very low activity towards ADP and an even lower activity towards ATP. As well as it doesn’t hydrolyze AMP and GMP. CANT1’s specific function is yet unknown, nevertheless its substrates are involved in several key signaling functions, including Ca2+ release, through activation of pyrimidinergic signaling. Mutations in the CANT1 gene are linked with Desbuquois dysplasia with hand anomalies.

Toll-interleukin1 receptor (TIR) domain containing adaptor protein (TIRAP) contains 1 TIR domain. TIRAP is an adapter molecule linked with toll-like receptors. TIRAP is required in TLR2 and TLR4 signaling pathways in the innate immune response. TIRAP activates NF-kappa-B, MAPK1, MAPK3 and JNK, which subsequently results in cytokine secretion and the inflammatory response. TIRAP is highly expressed in the liver, kidney, spleen, skeletal muscle and heart. TIRAP is also found in peripheral blood leukocytes, lung, placenta, small intestine, thymus, colon and brain.

TRAIL Receptor-3, also known as TNFRSF10C belongs to theTNF-receptor super family. TNFRSF10C contains an extracellular TRAIL-binding domain as well as a transmembranedomain, however no cytoplasmic death domain. Furthermore, TNFRSF10C is not capable of inducing apoptosis, and is considered toact as an antagonistic receptor which protects cells from TRAIL-induced apoptosis.

DNA polymerase beta (POLB) is a member of the DNA polymerase type-X family. In eukaryotic cells, POLB performs base excision repair necessary for DNA maintenance, replication, recombination, and drug resistance. POLB has 2 separate domains; the larger is the polymerase domain itself, whereas a small basic N-terminal domain contains an AP lyase activity which excises the abasic sugar-phosphate residue at the strand break. POLB fills single nucleotide gaps in DNA produced by the base excision repair pathway of mammalian cells. POLB overexpression, as seen in some human tumors, could convene an increase in spontaneous mutagenesis.

Polymerase II Polypeptide D (POLR2D) is a member of the eukaryotic RPB4 RNA polymerase subunit family. POLR2D is the fourth largest subunit of RNA polymerase II. Pol II is the main element of the basal RNA polymerase II transcription machinery. polymerase is responsible forsynthesizing messenger RNA in eukaryotes. In yeast, POLR2D subunit is connected with the polymeraseunder suboptimal growth conditions and might have a stress protective role. POLR2D catalyzes the transcription of DNA into RNA by the 4 ribonucleoside triphosphates as substrates.

Ganglioside GM2 activator (GM2A) is a small glycolipid transport protein which functions as a substrate specific co-factor for the lysosomal enzyme beta-hexosaminidase A. GM2A participates in lipid metabolism. GM2A protein is localized in lysosomes. The GM2A protein forms a large binding pocket for a number of single chain phospholipids and fatty acids. GM2A demonstrates calcium-independent phospholipase activity. GM2A stimulates ganglioside GM2 degradation by presenting GM2 to beta-hexosaminidase A. The Beta-hexosaminidase A, along with GM2A, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. GM2A gene mutations result in GM2-gangliosidosis type AB or the AB variant of Tay-Sachs disease.

MAGEA5 belongs to the MAGEA gene family which encodes proteins with 50 to 80% sequence identity to each other. The promoters and first exons of the MAGEA genes are variable, which signify that the presence of this gene family enables the same role to be expressed under diverse transcriptional controls. The MAGEA genes are clustered at chromosomal location Xq28. They are associated with several hereditary disorders, like dyskeratosis congenita. MAGEA5 gene encodes a protein which is C-terminally truncated compared to other family members, and can be alternatively interpreted to be a pseudogene.

MDC (CCL22) is a small cytokine that belongs to the CC chemokine family. CCL22 is one of several Cys-Cys (CC) cytokine genes clustered on the q arm of chromosome 16. MDC shows chemotactic activity for natural killer cells, chronically activated T lymphocytes, monocytes and dendritic cells. On the other hand, MDC shows a mild activity for primary activated T lymphocytes and has no chemoattractant activity for neutrophils, eosinophils and resting T lymphocytes. MDC may also have a role in the trafficking of activated T lymphocytes to inflammatory sites and other aspects of activated T lymphocyte physiology. MDC interacts with cell surface chemokine receptors CCR4. CCL22 is vastly expressed in macrophage and in monocyte-derived dendritic cells, and thymus. CCL22 is also found in the lymph node, appendix, activated monocytes, resting and activated macrophages. Lower expression of CCL22 can be seen in the lung and the spleen and very weak expression in the small intestine. In the lymph

The protein encoded by this gene is a cytokine that acts as a growth and differentiation factor for both B cells and eosinophils. This cytokine is a main regulator of eosinopoiesis, eosinophil maturation and activation. The elevated production of this cytokine is reported to be related to asthma or hypereosinophilic syndromes. The receptor of this cytokine is a heterodimer, whose beta subunit is shared with the receptors for interleukine 3 (IL3) and colony stimulating factor 2 (CSF2/GM-CSF). This gene, together with those for interleukin 4 (IL4), interleukin 13 (IL13), and CSF2, form a cytokine gene cluster on chromosome 5. This cytokine, IL4, and IL13 are found to be regulated coordinately by long-range regulatory elements spread over 120 kilobases on chromosome 5q31.