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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.

Integrins are heterodimeric proteins consist of alpha and beta subunits. There are more than 18 alpha and 8 beta subunits discovered in mammals. Integrin family members are membrane receptors that participates in cell adhesion and recognition in a variety of processes including embryogenesis, hemostasis, tissue repair, immune response and metastatic diffusion of tumor cells. ITGB1 encodes a beta subunit.

Transthyretin (TTR) is a circulating and abundant tetramer, which functions as a carrier protein of thyroid hormone and retinol binding protein. It is primarily produced in the liver, but also in the brain and eye. Mutations in the TTR gene cause the protein to dissociate into monomers that after misfolding assemble into amyloid fibrils deposits in a variety of organs. TTR is also the only gene known to be associated with familial TTR amyloidosis. The diseases that originate from mutations in the TTR gene include amyloidotic polyneuropathy, euthyroid hyperthyroxinaemia, amyloidotic vitreous opacities, cardiomyopathy, oculoleptomeningeal amyloidosis, meningocerebrovascular amyloidosis, carpal tunnel syndrome, etc.

IL4 is a pleiotropic cytokine produced by activated T cells. IL4 is a ligand for interleukin 4 receptor. The interleukin 4 receptor also binds to IL13, which may contribute to many overlapping functions of this cytokine and IL13. STAT6, a signal transducer and activator of transcription, has been shown to play a central role in mediating the immune regulatory signal of this cytokine. This gene, IL3, IL5, IL13, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL13. IL4, IL13 and IL5 are found to be regulated coordinately by several long-range regulatory elements in an over 120 kilobase range on the chromosome. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.

N-Acetylglucosamine Kinase (NAGK) is a part of the eukaryotic-type N-acetylglucosamine kinase family. NAGK transforms endogenous N-acetylglucosamine (GlcNAc), a main component of complex carbohydrates, from lysosomal degradation or nutritional sources into GlcNAc 6-phosphate. NAGK is a significant salvage enzyme of amino sugar metabolism in mammals which has ManNAc kinase activity.

Cyclin-dependent kinase inhibitor 1B (CDKN1B) is a member of the Cip/Kip family of cyclin dependent kinase (Cdk) inhibitor proteins. The CDKN1B protein binds to and prevents the activation of cyclin E-CDK2 or cyclin D-CDK4 complexes, and so controls the cell cycle progression at G1. CDKN1B is often referred to as a cell cycle inhibitor protein since its major function is to stop or slow down the cell division cycle. The degradation of the CDKN1B protein, which is triggered by its CDK dependent phosphorylation and ensuing ubiquitination by SCF complexes, is compulsory for the cellular transition from inactive to the proliferative state.

IL-7 is a cytokine important for B and T cell development. This cytokine and the hepatocyte growth factor (HGF) form a heterodimer that functions as a pre-pro-B cell growth-stimulating factor. This cytokine is found to be a cofactor for V(D)J rearrangement of the T cell receptor beta (TCRB) during early T cell development. This cytokine can be produced locally by intestinal epithelial and epithelial goblet cells, and may serve as a regulatory factor for intestinal mucosal lymphocytes. Knockout studies in mice suggested that this cytokine plays an essential role in lymphoid cell survival.

Thymidylate synthase catalyzes the methylation of deoxyuridylate to deoxythymidylate using 5,10-methylenetetrahydrofolate as a cofactor which maintains the dTMP (thymidine-5-prime monophosphate) pool vital for DNA replication and repair. Thymidylate synthase plays an important role as a cancer chemotherapeutic agent. Thymidylate synthase is the primary site of action for 5-fluorouracil, 5-fluoro-2-prime-deoxyuridine, and several folate analogs.

BPGM is found at high concentrations in red blood cells where it binds to and decreases the oxygen affinity of hemoglobin. PGM deficiency increases the oxygen affinity of cells. BPGM is a multifunctional enzyme that catalyzes 2,3-DPG synthesis through its synthetase activity, and 2,3-DPG degradation using its phosphatase activity. BPGM has phosphoglycerate phosphomutase activity. Mutations in BPGM cause hemolytic anemia. BPGM catalyzes the reaction of EC 5.4.2.1 (mutase) and EC 3.1.3.13 (phosphatase), but with a reduced activity.

The Fas receptor (CD95) mediates apoptotic signaling by Fas-ligand expressed on the surface of other cells. The Fas-FasL interaction plays an important role in the immune system and lack of this system leads to autoimmunity, indicating that Fas-mediated apoptosis removes self-reactive lymphocytes. Fas signaling is also involved in immune surveillance to remove transformed cells and virus infected cells. Binding of FAS to oligimerized FasL on another cell activates apoptotic signaling through a cytoplasmic domain termed the death domain that interacts with signaling adaptors including FAF, FADD and DAX to activate the caspase proteolytic cascade. Caspase-8 and caspase-10 are first activated, to then cleave and activate downstream caspases, and a variety of cellular substrates that lead to cell death. Caspases cleave nuclear lamins, causing the nucleus to break down and lose its normal structure and another caspase substrate is DFF, inducing cleavage and degradation of the genome. Other caspase substrates are involved in cytoskeletal structure, cell cycle regulation and signaling pathways. Activation of JNK kinase, activation of Jun, and production of ceramide may also play roles in Fas-mediated apoptosis. Activation of fas-mediated apoptosis is opposed by I-FLICE and FAP. Viruses and tumors may escape immune surveillance in part through suppression of fas-mediated apoptosis using similar mechanisms.

Omentin is a recently recognized gene highly localized to the mental tissue (visceral adipose tissue). Omentin is present in the stromal vascular cells in the adipose tissue rather than in the adipocytes. Omentin is predominantly expressed in the visceral adipose tissue than the subcutaneous tissue, with the omentin mRNA being 150 times higher in the visceral adipose tissue. Omentin has also been detected in human blood using western blot analysis, and seems to increase insulin-stimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of insulin presence. Its role in glucose metabolism and obesity remains to be described; an insulin-sensitizing action is possible.Differences in Omentin expression has been noted in adipose tissue from normals and patients with inflammatory bowel disease although its significance is unknown

H3N2 is a subtype of the influenza A virus. Its name derives from the forms of the two kinds of proteinson the surface of its coat, hemagglutinin(H) and neuraminidase(N). H3N2 exchanges genes for internal proteins with other influenza subtypes. H3N2 has tended to dominate in prevalence over H1N1, H1N2, and influenza B. H3N2 strain descended from H2N2by antigenic shift, in which genes from multiple subtypes re-assorted to form a new virus. Both the H2N2and H3N2 strains contained genesfrom avian influenzaviruses.

Von Hippel-Lindau disease is a dominant inherited syndrome characterized by the predisposition to develop various kinds of benign and malignant tumors, including clear cell renal carcinomas, pheochromocytomas and hemangioblastomas of the central nervous system and retina. VHL syndrome is caused by germline mutation in the VHL tumor suppressor, and VHL tumors are associated with loss or mutation of the remaining wild-type allele. VHL has two domains: a roughly 100-residue NH2-terminal domain rich in b sheet (b-domain) and a smaller a-helical domain (a-domain), held together by two linkers and a polar interface. VHL protein is also involved in the degradation of hypoxia-inducible factor (HIF).

Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

The protein encoded by this gene is a cytokine that regulates T and natural killer cell activation and proliferation. This cytokine and interleukine 2 share many biological activities. They are found to bind common hematopoietin receptor subunits, and may compete for the same receptor, and thus negatively regulate each other's activity. The number of CD8+ memory cells is shown to be controlled by a balance between this cytokine and IL2. This cytokine induces the activation of JAK kinases, as well as the phosphorylation and activation of transcription activators STAT3, STAT5, and STAT6. Studies of the mouse counterpart suggested that this cytokine may increase the expression of apoptosis inhibitor BCL2L1/BCL-x(L), possibly through the transcription activation activity of STAT6, and thus prevent apoptosis. Two alternatively spliced transcript variants of this gene encoding the same protein have been reported.

ORF73 protein of human herpesvirus 8 is a Kaposi''s sarcoma-associated herpesvirus latent protein that is suspected of playing a critical role in modulating viral and cellular gene expression. ORF73 is linked to cellular chromatin and stays on the chromosomes during cell division. ORF73 maintains the viral genomes during cell division by tethering the viral episomes to the chromosomes. ORF73 binds directly to replication origin recognition complexes which are primarily connected with the terminal repeat region of the HHV8 genome.

GIPC2 is a 315 aa protein which is restricted to the cytoplasm and holds one PDZ domain. GIPC2 is expressed in large quantities in colon and kidney and in small quantities in adult liver. GIPC2 has a vital part in human gastric cancer by control of growth factor signaling or cell adhesion.

Troponin I, (TNNI1) is a member of the troponin I family. Troponin complex has 3 subunits, TNNI1 known as the inhibitory Subunit which prevents the actin-myosin interactions and thus mediating striated muscle relaxation. TNNI1 combines with tropomyosin and regulates calcium sensitivity of striated muscles by structural modifications in actin-myosin complexes.

Vps20-associated 1 homolog (VTA1) is a member of the VTA1 family. The VTA1 protein is involved in the endosomal multivesicular bodies (MVB) pathway. Furthermore, VTA1 is interacts with CHMP1B, CHMP2A, CHMP5, VPS4B, KIAA0174 (IST1) and possibly CHMP3. VTA1 is believed to be a cofactor of VPS4A/B, which catalyzes membrane-associated ESCRT-III assemblies. In addition, VTA1 is involved in the sorting and down-regulation of EGFR and also in HIV-1 budding.

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

Vascular endothelial growth factoris an important signaling proteininvolved in both vasculogenesisand angiogenesis. As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/macrophagemigration, neurons, cancer cells, kidney epithelial cells ).VEGF mediates increased vascular permeability, induces angiogenesis, vasculogenesis and endothelial cell growth, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesisand cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor.
Elevated levels of this protein is linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

CDC37 is an essential protein in Saccharomyces cerevisiae and is a molecular chaperone with precise function in cell signal transduction. CDC37 forms a complex/associates with Hsp90 molecular chaperone as one of several auxiliary proteins that are collectively referred to as Hsp90 co-chaperones. CDC37 also forms complex with a number of protein kinases such as CDK4, CDK6, SRC, RAF-1, MOK, as well as eIF2 alpha kinases. CDC34 is involved in directing Hsp90 to its target kinases. CDC37 up-regulation is a common early event in some localized human cancers. CDC37 is necessary for maintaining prostate tumor cell growth and represents a novel target in the exploration for multitargeted therapies. CDC37 plays a role in regulating Hsp90 ATPase activity. CDC37 binds to Akt and HSP90 in the signal transduction pathway in human tumor cells. Tnf-induced recruitment and activation of the IKK complex require Cdc37 and Hsp90. CDC37 and heat shock protein 90 bind specifically to the kinase domain of LKB1.