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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.

SNAP-25 is an necessary element of the core complex that is responsible for presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters and this protein exists as two alternative isoforms, SNAP25A and SNAP25B which differ by 9 amino acids in central portion of these proteins.

SOX2 is a transcription factor that forms a trimeric complex with OCT4 on DNA and controls the expression of a number of genes involved in embryonic development such as YES1, FGF4, UTF1 and ZFP206. SOX4 is important for early embryogenesis and for embryonic stem cell pluripotency.

Chemokine (C-X-C motif) ligand 5 (CXCL5) is a small cytokine belonging to the CXC chemokine family that is also known as epithelial-derived neutrophil-activating peptide 78 (ENA-78). It is produced following stimulation of cells with the inflammatory cytokines interleukin-1 or tumor necrosis factor-alpha. Expression of CXCL5 has also been observed in eosinophils. This chemokine stimulates the chemotaxis of neutrophils possesses angiogenic properties. It elicits these effects by interacting with the cell surface chemokine receptor CXCR2. The gene for CXCL5 is encoded on four exons and is located on human chromosome 4 amongst several other CXC chemokine genes. CXCL5 has been implicated in connective tissue remodelling.

Neurexophilin 1 (NXPH1) is a part of the neurexophilin family which encodes a secreted protein with a variable N terminal domain, an extremely conserved, N-glycosylated central domain, a short linker region, and a cysteine-rich Cterminal domain. NXPH1 shapes a very tight complex with alpha neurexins, a group of proteins which promote adhesion among dendrites and axons.

Defensins form a family of microbicidal and cytotoxic peptides made by neutrophils. Members of the defensin family are highly similar in protein sequence. This gene encodes defensin, beta 103A, which has broad spectrum antimicrobial activity and may play an important role in innate epithelial defense.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

PDCD6IP is a Class E VPS protein which participates in concentration and sorting of cargo proteins of the multivesicular body or incorporation into intralumenal vesicles that are generated by invagination and scission from the limiting membrane of the endosome. PDCD6IP binds to the phospholipid lysobisphosphatidic acid which is abundant in MVBs internal membranes. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. PDCD6IP is an adapter for a subset of ESCRT-III proteins, such as CHMP4, to function at distinct membranes. PDCD6IP is mandatory for completion of cytokinesis. PDCD6IP takes part in HIV-1 virus budding. PDCD6IP replaces TSG101 in its function of supporting HIV-1 release. PDCD6IP takes part in the regulation of both apoptosis and cell proliferation. PDCD6IP is a cytoplasmic protein that cooperates with apoptosis-associated proteins (ALG-2 and PDCD6) and with the endocytosis-regulator CIN85. Overexpression of PDCD6IP and endophilin

S100A9 is part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100A9 protein is localized in the cytoplasm and/or nucleus of a wide range of cells, and participates in the regulation of several cellular processes such as cell cycle progression and differentiation. S100 genes include no less than 13 proteins which are localized as a cluster on chromosome 1q21. S100A9 is involved in the inhibition of casein kinase and altered expression of this protein is associated with the disease cystic fibrosis.

CA, also known as carbonic anhydrase is an enzyme that functions around the involvement of CO2 + H2O to HCO3- + H+ (conversion of CO2 to bicarbonate & protons). This enzyme holds a Zn ion as part of its active site. The central function of CA is to preserve the acid-base homeostasis within the blood and various organs. carbonic anhydrase assists Carbonic Anhydrase I to move CO2 to and from tissues.

Brain Expressed X-Linked 1 (BEX1) which participates in cell cycle progression and neuronal differentiation, is a signaling adapter molecule involved in p75NTR/NGFR signaling. BEX1 inhibits neuronal differentiation in response to nerve growth factor. BEX1 links between the cell cycle and neurotrophic factor signaling by acting as an upstream modulator of receptor signaling, adjusting biological responses to external signals with internal cellular states.

Ostreolysin is extracted from Pleurotus ostreatus (oyster mushroom). It is a pore forming protein, which contains a lytic part to both cholesterol and sphingomyelin containing membranes. Because of their cholesterol content and the appearance of ostreolysin in the detergent resistant membranes, ostreolysin is cytotoxic towards the ovary cells of Chinese hamster. It seems that Ostreolysin spots a rich lipid cholesterol phase, presumably the liquid ordered phase.

ZW10 Interacting Kinetochore Protein (ZWINT) is involved in kinetochore function. ZWINT is part of the MIS12 complex, which is essential for kinetochore formation and spindle checkpoint activity. ZWINT is localized to the cytoplasm during interphase and to kinetochores from late prophase to anaphase. ZWINT interacts with ZW10 (Zeste White 10) and regulates the association between ZW10 and kinetochores. ZWINT gene defects are linked with the pathogenesis of Roberts’s syndrome, an autosomal recessive disorder characterized by growth retardation due to premature chromosome separation.

HLH (helix-loop-helix) proteins are a putative transcription factors family. Several HLH proteins take part in growth and development of an extensive range of tissues and species. NHLH1 functions as a DNA-binding protein and has a role in the regulation of cell-type determination in the developing nervous system.

Ferritin is the main intracellular iron storage protein in prokaryotes and eukaryotes. Ferritin’s major functions are the storage of iron in a soluble and nontoxic state and its release in a controlled fashion. An iron-containing protein complex is found mostly in the intestinal mucosa, spleen, and liver. Ferritin is composed of 24 subunits of the heavy and light chains. Variation in ferritin subunit composition may influence the rates of iron uptake and release in different tissues. Defects in the light chain ferritin gene are linked to a number of neurodegenerative diseases and hyperferritinemia-cataract syndrome. The genes that encode the light and heavy chains are on located different chromosomes. The light chain genes are in chromosome region 19q13.3-q13.4 whilst those for the heavy chain are in chromosome region 11q12-q13. Ferritin is shaped like a hollow sphere, inside which the iron is stored in the Fe(III) oxidation state. The iron is integrated in the mineral ferrihydrite, [FeO(OH)]8[FeO(H2PO4)], which is attached to the inner wall of the sphere. To release iron once the body needs it, the iron must be altered from the Fe(III) to the Fe(II) oxidation state. Subsequently, the iron leaves through channels in the spherical structure. Therefore, the structure of ferritin is tremendously important for the protein's ability to store and release iron in a controlled mode.
The amount of ferritin in the blood (serum ferritin level) is directly related to the amount of iron stored in the body. The body has a "buffer" against iron deficiency (if the blood has too little iron, ferritin can release more) and, to a lesser extent, iron overload (if the blood and tissues of the body have too much iron, ferritin can help store the excess iron).

The protein encoded by this gene is a member of the glial cell line-derived neurotophic factor (GDNF) family of ligands which are a group of ligands within the TGF-beta superfamily of signaling molecules. GDNFs are unique in having neurotrophic properties and have potential use for gene therapy in neurodegenrative disease. Artemin has been shown in culture to support the survival of a number of periferal neuron populations and at least one population of dopaminergic CNS neurons. Its role in the PNS and CNS is further substantiated by its expression pattern in the proximity of these neurons. This protein is a ligand for the RET receptor and uses GFR-alpha 3 as a coreceptor. Four alternatively spliced transcripts have been described, two of which encode the same protein.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

Metallothionein 3 (MT3) contains 3 zinc and 3 copper atoms per polypeptide chain and a minor amount of cadmium. MT3 inhibits survival and neurite formation of cortical neurons in vitro. MT3 also binds heavy metals.

Desmin is a muscle-specific class III intermediate filament. Homopolymers of this protein form a stable intracytoplasmic filamentous network connecting myofibrils to each other and to the plasma membrane. Mutations in this gene are associated with desmin-related myopathy, a familial cardiac and skeletal myopathy (CSM), and with distal myopathies.

TCEAL3 belongs to the transcription elongation factor A (SII)-like (TCEAL) gene family. TCEAL family members hold TFA domains and operate as nuclear phosphoproteins which control transcription in a promoter context-dependent fashion. Various family members are situated in the X chromosome.