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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.

Prolactin is a neuroendocrine hormone synthesized primarily by the pituitary gland but also a variety of other cell types including the placenta, brain and uterus. Prolactin’s primary function is to promote and maintain lactation and also in breast cancer development, regulation of reproductive function and immunoregulation.

Glycoprotein-9 (GP9) is a small membrane glycoprotein found on the surface of human platelets. GP9 forms a one to one noncovalent complex with glycoprotein Ib, a platelet surface membrane glycoprotein complex which functions as a receptor for von Willebrand factor. The complete receptor complex includes noncovalent association of the alpha and beta subunits with the protein and platelet glycoprotein V. GP9 gene defects cause the Bernard-Soulier syndrome, aka giant platelet disease whose patients have unusually large platelets and have a clinical bleeding tendency.

Chemokine (C-X-C motif) ligand 3 (CXCL3) is a small cytokine belonging to the CXC chemokine family that is also known as GRO3 oncogene (GRO3), GRO protein gamma (GROg) and macrophage inflammatory protein-2-beta (MIP2b). CXCL3 controls migration and adhesion of monocytes and mediates it effects on its target cell by interacting with a cell surface chemokine receptor called CXCR2. The gene for CXCL3 is located on chromosome 4 in a cluster of other CXC chemokines.

ACTN1 encodes a nonmuscle, cytoskeletal, alpha actinin isoform and maps to the same site as the structurally similar erythroid beta spectrin gene. Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments.

ASS1 is involved in the urea cycle, which is a sequence of chemical reactions that is localized in liver cells. The urea cycle processes excess nitrogen that is generated as the body uses proteins. The surplus nitrogen is used to create a molecule called urea, which is excreted from the body in urine.

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

HBsAg is the surface antigenof the Hepatitis-B-Virus (HBV). The capsidof a virus has different surface proteins from the rest of the virus. The antigen is a protein that binds specifically on one of these surface proteins. It is commonly referred to as the Australian Antigen.

Insulin Receptor (INSR) is a receptor tyrosine kinase which mediates the pleiotropic actions of insulin. Binding of insulin to the insulin receptor (INSR) stimulates glucose uptake. Once the precursor signal peptide is removed, the insulin receptor precursor is post-translationally cleaved into 2 chains (alpha and beta) which are covalently linked. Insulin binding initiates phosphorylation of several intracellular substrates, including, insulin receptor substrates (IRS1, 2, 3, 4), SHC, GAB1, CBL and other signaling intermediates. Each of these phosphorylated proteins function as docking proteins for other signaling proteins which contain Src-homology-2 domains (SH2 domain) that specifically recognize different phosphotyrosines residues, including the p85 regulatory subunit of PI3K and SHP2.

GroEL, HSP60 is a chaperonin located in the mitochondria which is responsible for the transportation & refolding of proteins from the cytoplasm directly into the mitochondrial matrix. GroEL is regulated by the HSP10 cochaperonin, which is a single heptameric protein ring having a molecular mass of 10 kDa which form a unique complex with HSP60. HSP10, GroES coordinates the ATPase activity of the HSP60 subunits in order to allow the release of bound polypeptide in a manner that is productive for its correct folding.

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and a member of the peptidase C1 family. CTSZ, which is known also as cathepsin X and cathepsin P, exhibits carboxy-monopeptidase and carboxy-dipeptidase activities. CTSZ is expressed ubiquitously in cancer cell lines and primary tumors and as other members of this family, takes part in tumorigenesis.

Synaptotagmin-4 (SYT4) is a part of the synaptotagmin proteins family. Synaptotagmins are a large gene family of synaptic vesicle type III integral membrane proteins that operate as regulators of both exocytosis and endocytosis and are involved in neurotransmitter secretion from small secretory vesicles. SYT4 is expressed in neuronal tissues, and has the highest mRNA levels in the hippocampus. The proximity of the SYT4 gene to markers of several psychiatric disorders implies an involvement of SYT4 in human disease such as pheochromocytoma, and parkinson's disease.

Fc Fragment Of IgA Receptor, also known as FCAR, is part of the multichain immune recognition receptor family which is the most abundant immunoglobulin in mucosal areas however it is only the second most common antibody isotype in serum. FCAR participates in both pro-and anti-inflammatory responses depending on the state of IgA bound. FCAR is also a vital Fc receptor for neutrophil killing of tumor cells. Once FCAR expressing neutrophils interact with IgA-opsonized tumor cells, the neutrophils not only show antibody-dependent cell-mediated cytotoxicity, but also release the cytokines TNF-α and IL-1β which cause increased neutrophil migration to the site.

Melanoma-associated antigen D1 (MAGED1) belongs to the melanoma antigen gene (MAGE) family and expressed in virtually all normal adult tissues. MAGED1 is involved in the p75 neurotrophin receptor mediated programmed cell death pathway. MAGED1 is involved in Prader-Willi syndrome including hyperphagia, repetitive and compulsive behaviors, and cognitive impairment. MAGED1 is involved in the apoptotic response following NGF (nerve growth factor) binding in neuronal cells. MAGED1 hinders cell cycle progression, and facilitates NGFR-mediated apoptosis. MAGED1 functions as a regulator of the function of DLX family members. MAGED1 has a role in the circadian rythm regulation.

TRIM21 is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The 52 kDa Ro protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. Ro/SSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Ribonucleoprotein particle is composed of a single polypeptide and one of four small RNA molecules. The RoSSA is present in all mammalian cells studied but has no known function. At least 2 isoforms are present in nucleated and red blood cells, and tissue specific differences in Ro/SSA proteins were identified.

Kallikrein-3 (KLK3) belongs to the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins are involved in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 is assumed to act normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

Beta-crystallin A4 (CRYBA4) is a member of the beta/gamma-crystallin family which are the dominant structural components of the vertebrate eye lens. Beta-crystallins construct aggregates of various sizes and are able to self-associate to form dimers or to form heterodimers with other beta-crystallins. The CRYBA4 gene being a beta acidic group member is part of a gene cluster with beta-B1, beta-B2, and beta-B3.

Interleukin-10 is a multifunctional cytokine produced by a variety of cell types including T helper cells activated B cells and activated macrophages. Interleukin-10 regulates immune-mediated inflammation and modulates the function of cells such as lymphocytes, monocytes, natural killer cells and dendritic cells.

Human interleukin family 1, member 5 (IL-1F5 / FIL1-delta) belongs to the interleukin 1 cytokine family. IL1F5 is expressed by a variety of cells including monocytes, Bcells, dendritic cells/Langerhans cells, keratinocytes,and gastric fundus Parietal and Chief cells. IL1F5 is an antagonist of IL1F9; however IL1F5 activity related to receptor binding remains unclear. Human and mouse IL1F5 share 90% amino acid sequence identity.

Inhibitor of Growth Family, Member 2 (ING2) belongs to the inhibitor of growth (ING) family. ING family members associate with and modulate the activity of histone acetyltransferase (HAT) and histone deacetylase (HDAC) complexes and serve in DNA repair and apoptosis. ING2 appears to be involved in p53/TP53 activation and p53/TP53-dependent apoptotic pathways, most likely by enhancing acetylation of p53/TP53. ING2 is a component of an mSin3A-like corepressor complex, which is probably involved in deacetylation of nucleosomal histones. ING2 activity is modulated by binding to phosphoinositides (PtdInsPs).

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 INSstimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of INS presence. Its role in glucose metabolism and obesity remains to be described; an INS-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.

Endoglin is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex.The Endoglin protein consists of a homodimer of 180 kDA with disulfide links. Endoglin has been found on endothelial cells, activated macrophages, fibroblasts, and smooth muscle cells. Furthermore, Endoglin has been found to be part of the TGF-beta1 receptor complex. Endoglin thus may be involved in the binding of TGF-beta1, TGF-beta3, activin-A, BMP-2, and BMP-7. Beside TGF-beta signaling endoglin may have other functions. It has been postulated that endoglin is involved in the cytoskeletal organization affecting cell morphology and migration. Endoglin has a role in the development of the cardiovascular system and in vascular remodeling. Endoglin expression is regulated during heart development . Experimental mice without the endoglin gene die due to cardiovascular abnormalities.