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Prohibitin 2, also known as PHB2, mediates transcriptional repression by nuclear hormone receptors via recruitment of histone deacetylases by similarity. PHB2 functions as an estrogen receptor (ER)-selective coregulator which potentiates the inhibitory activities of antiestrogens and represses the activity of estrogens. PHB2 which is involved in regulating mitochondrial respiration activity and in aging, competes with NCOA1 for modulation of ER transcriptional activity.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation.

CDNF is a member of the ARMET family and acts as a trophic factor for neurons. CDNF inhibits the (6-OHDA)-induced degeneration of neurons. When CDNF controlled after 6-OHDA-lesioning, it reestablishes the function and inhibits the degeneration of neurons in substantia nigra. CDNF is universally expressed in neuronal and non-neuronal tissues. The highest levels in the brain are found in the optic nerve and corpus callosum.

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

Actin depolymerizing factor (Destrin/DSTN) belongs to the ADF/Cofilin/destrin superfamily which has the ability to swiftly depolymerize F-Actin in a stoichiometric mode. The ADF family of proteins is responsible for enhancing the turnover rate of actin in vivo. Destrin is a small phosphoinositide-sensitive actin-binding protein capable of depolymerizing actin-filaments in vitro. DSTN functions in a pH-independent manner. DSTN is found in a variety of epithelial and endothelial cells, however it is virtually nonexistent in adult mouse heart and skeletal muscle cells. Destrin shares a 71% sequence homology with Cofilin, however the 2 proteins vary in their interaction with Actin.

TPPP3 is a member of the TPPP family and is found in the cytoplasm. TPPP3 binds tubulin, has microtubule bundling activity takes part in mitosis and cell proliferation.

Cellular Repressor of E1A-Stimulated Genes 1 (CREG1) both activates and inhibits gene expression to stimulate cellular proliferation and hinder differentiation. CREG1 antagonizes transcriptional activation and cellular transformation by E1A. CREG1 shares partial sequence similarity with E1A and binds both the general transcription factor TBP and the tumor suppressor pRb in vitro. CREG1 contributes to the transcriptional control of cell growth and differentiation.

Human Cu/Zn Superoxide Dismutase (SOD1) catalyzes the reaction between superoxide anions and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide. SOD1 binds copper and zinc ions and is 1 of 3 isozymes accountable for destroying free superoxide radicals in the body. The encoded protein neutralizes supercharged oxygen molecules, which can damage cells if their levels are not controlled. Mutations in SOD1 cause a form of familial amyotrophic lateral sclerosis.

TARC cDNA encodes a 94 amino acid precursor protein with a 23 amino acid residue signal peptide that is cleaved off to generate the 71 amino acid residue mature secreted protein. Along with CC chemokine family members, CCL-17 has approximately 24-29% amino acid sequence identity with RANTES, MIP-1a, MIP-1b, MCP-1, MCP-2, MCP-3 and I-309. TARC is expressed in thymus, and at a lower level in the lung, colon, and small intestine. TARC is in addition transiently expressed in stimulated peripheral blood mononuclear cells. Recombinant TARC has been shown to be chemotactic for T cell lines but not monocytes or neutrophils. CCL-17 was recently identified to be a specific functional ligand for CCR4, a receptor that is selectively expressed on T cells. CCL17 is one of quite a few Cys-Cys (CC) cytokine genes clustered on the q arm of chromosome 16. CCL17 shows chemotactic activity for T lymphocytes, but not monocytes or granulocytes. CCL17 binds to chemokine receptors CCR4 and CCR8. This chemokine plays important roles in T cell development in thymus as well as in trafficking and activation of mature T cells.

Angiopoietin-related protein 7 (ANGPTL7), belongs to the angiopoietin-like family of molecules. ANGPTL7 is expressed in the corneal stroma, trabecular meshwork, and sclera. ANGPTL7 production is up-regulated in trabecular meshwork cells by glucocorticoids and TGF-Beta and in cartilage by TNF-alpha.

Prealbumin is a thyroid hormone-binding protein that transports thyroxine from the bloodstream to the brain. Prealbumin is a carrier protein which transports thyroid hormones in the plasma and cerebrospinal fluid, and also transports retinol (vitamin A) in the plasma. Transthyretin consists of a tetramer of identical subunits and is dominantly produced in the liver. Mutations in Prealbumin are related to amyloid deposition, affecting predominantly peripheral nerve and/or the heart. The diseases caused by mutations include amyloidotic polyneuropathy, euthyroid hyperthyroxinaemia, amyloidotic vitreous opacities, cardiomyopathy, oculoleptomeningeal amyloidosis, meningocerebrovascular amyloidosis, and carpal tunnel syndrome. Prealbumin is an indicator of protein-energy malnutrition since it has a circulating half life of 2 days and reacts swiftly to changes in nutritional status.

Gastrokine-1 (GKN1) is a member of the gastrokine family. GKN1 has mitogenic activity and is involved in preserving the integrity of the gastric mucosal epithelium. GKN1 is down-regulated in human gastric cancer tissue in comparison to normal gastric mucosa. GKN1 is expressed in the stomach; however no expression is detected in cancer tissue or gastric cancer cell lines.

KLK7 catalyzes the degradation of intercellular cohesive structures in the cornified layer of the skin in the continuous shedding of cells from the skin surface. Specific for amino acid residues with aromatic side chains in the P1 position. KLK7 is involved in the activation of precursors to inflammatory cytokines.

Chemokine (C-X-C motif) ligand (CXCL7) is a small cytokine belonging to the CXC chemokine family. It is a protein that is released in large amounts from platelets following their activation. It stimulates various processes including mitogenesis, synthesis of extracellular matrix, glucose metabolism and synthesis of plasminogen activator.

Calcium-binding protein P22 is a phosphoprotein that binds to the sodium-hydrogen exchangers (NHEs). CHP is an essential cofactor which maintains the physiological activity of NHE family members. CHP has protein sequence resemblance to calcineurin B and it is also identified to be an endogenous inhibitor of calcineurin activity.CHP is necessary for constitutive membrane traffic. CHP Inhibits GTPase-stimulated Na(+)/H(+) exchange. CHP inhibits calcineurin phosphatase activity. Required for activity of SLC9A1/NHE1.

OX40 Ligandis a part of the tumor necrosis factor (TNF)receptor family. OX40L receptor is OX40 which is expressed predominantly on activated CD4+ T cells.OX40 Ligandis expressed on various antigen-presenting cells such asmacrophages, DC2sand activated Blymphocytes. Expression of OX40 is momentary following engagement of T cell receptors. The ligation of OX40-OX40L stimulates proliferation anddifferentiation of activated B cells,increases immunoglobulin secretion and is also a sourceof survival signal for T cells and enables the development of memory T cells.

MCSFR which is also familiar as CSF1R, is part of the type3 subfamily of receptor tyrosine kinases. MCSFR is expressed mainly on cells of the monocyte and macrophage lineage, stem cells, and in the growing placenta. Most of the biological effects of this cytokine are mediated by MCSFR. MCSFR contains an extracellular ligand-binding domain, a single membrane-spanning segment, and an intracellular tyrosine kinase domain. Originally CSF1 and this receptor were implicated as vital for normal trophoblastic implantation as well as monocyte development. The role of CSF1/CSF1R in normal mammary gland development is actually very interesting since this connection has also been discovered in the biology of breast cancer with the results of abnormal expression of CSF1 and its receptor. Likewise, in Alzheimer's disease and after brain injuries an increased level of CSF1R was found in the microglia, which causes the microglia to become more active.

KLRC2 has a part as a receptor for the recognition of MHC class I HLA-E molecules by NK cells and some cytotoxic T-cells. The group, designated KLRC (NKG2) are expressed mainly in natural killer (NK) cells and encodes a family of transmembrane proteins categorized by a type II membrane orientation (extracellular C terminus) and the presence of a C-type lectin domain. The KLRC (NKG2) gene family is situated inside the NK complex, a region which holds a few C-type lectin genes specially expressed on NK cells. KLRC2 alternative splice variants are known but their full-length nature is yet to be determined.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

The secreted polypeptide noggin, encoded by the NOG gene, binds and inactivates members of the transforming growth factor-beta (TGF-beta) superfamily signaling proteins, such as bone morphogenetic protein-4 (BMP4). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic gradients. Noggin appears to have pleiotropic effect, both early in development as well as in later stages. It was originally isolated from Xenopus based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.

GDNF family receptor alpha-1 (GFRA1) belongs to the GDNF receptor family. GFRA1 is a glycosyl-phosphatidylinositol(GPI)-linked cell surface receptor for both Glial cell line-derived growth factor (GDNF), neurturin (NTN), and mediates activation of the RET tyrosine kinase receptor. The GFRA1 protein is a potent survival factor for central and peripheral neurons, and is vital for the development of kidneys and the enteric nervous system.

Chemokine (C-X-C motif) ligand 2 (CXCL2) is a small cytokine belonging to the CXC chemokine family that is also called macrophage inflammatory protein 2-alpha (MIP2-alpha), Growth-regulated protein beta (Gro-beta) and Gro oncogene-2 (Gro-2). CXCL2 is 90% identical in amino acid sequence as a related chemokine, CXCL1. This chemokine is secreted by monocytes and macrophages and is chemotactic for polymorphonuclear leukocytes and hematopoietic stem cells. The gene for CXCL2 is located on human chromosome 4 in a cluster of other CXC chemokines. CXCL2 mobilizes cells by interacting with a cell surface chemokine receptor called CXCR2.

Ubiquilin-2, also known as UBQLN2 contains an N-terminal ubiquitin-like domain and a C-terminal ubiquitin-associated domain. UBQLN2 is physically linked with proteasomes as well as ubiquitin ligases, and therefore is considered to functionally connect the ubiquitination machinery to the proteasome in order to affect in vivo protein degradation. Furthermore, UBQLN2 binds the ATPase domain of the Hsp70-like Stch protein. Among the diseases which are associated with UBQLN2: Amyotrophic lateral sclerosis 15, with or without frontotemporal dementia as well as Amyotrophic lateral sclerosis type 15.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.