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Beta-1,3-glucuronyltransferase 3 (B3GAT3) is involved in forming the linkage tetrasaccharide present in heparan sulfate and chondroitin sulfate. B3GAT3 has a part in the biosynthesis of l2/HNK-1 carbohydrate epitope on glycoproteins. B3GAT3 shows strict specificity for Gal-beta-1,3-Gal-beta-1,4-Xyl, exhibiting negligible incorporation into other galactoside substrates including Galbeta1-3Gal beta1-O-benzyl, Galbeta1-4GlcNAc and Galbeta1-4Glc.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

Human PDE6D was initially identified as a fourth subunit of rod-specific cGMP phosphodiesterase, PDE6. PDE6D is an Oligomer composed of two catalytic chains (alpha and beta), an inhibitory chain (gamma) and the delta chain. PDE6D interacts with RPGR, ARL2 and ARL3. The catalytically active PDE6 is a heterodimer (αβ) that is controlled by two inhibitory γ subunits. Since PDE6D does not change the catalytic properties of PDEαβ, its function is still unanswered. PDE6D is expressed specifically in the retina.

PDIA3 is an enzyme that belongs to the endoplasmic reticulum and interacts with lectin chaperones calreticulin and calnexin to modulate folding of newly synthesized glycoproteins. PDIA3 has protein disulfide isomerase activity. Complexes of lectins and PDIA3 mediate protein folding by promoting formation of disulfide bonds in their glycoprotein substrates. PDIA3 is expressed in the lumbar spinal cord from rats submitted to peripheral lesion during neonatal period. PDIA3 interacts with thiazide-sensitive sodium-chloride cotransporter in the kidney and is induced by glucose deprivation. PDIA3 is part of the major histocompatibility complex (MHC) class I peptide-loading complex (TAP1), which is important for formation of the final antigen conformation and export from the endoplasmic reticulum to the cell surface.

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.

TFPI is a protease inhibitor which controls the tissue factor (TF)-dependent pathway of blood coagulation. The coagulation process starts with the creation of a factor VIIa-TF complex, that proteolytically triggers additional proteases (factors IX and X) and eventually results in a fibrin clot. TFPI inhibits the activated factor X and VIIa-TF proteases in an autoregulatory loop. TFPI is glycosylated and predominantly located in the vascular endothelium and plasma in both free forms and complexed with plasma lipoproteins. A number of alternatively spliced transcript variants of this gene have are known, however the full-length nature of several of these variants were not yet established.

Phospholipase A2 (PLA2) catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid (AA), a precursor of eicosanoids including prostaglandins and leukotrienes. The same reaction also produces lysophosholipids, which represent another class of lipid mediators.
The secretory PLA2 (sPLA2) family, in which 10 isozymes have been identified, consists of low molecular weight, Ca2+-requiring secretory enzymes that have been implicated in a number of biological processes, such as modification of eicosanoid generation, inflammation, and host defense.
This enzyme has been proposed to hydrolyze phosphatidylcholine (PC) in lipoproteins to liberate lyso- PC and free fatty acids in the arterial wall, thereby facilitating the accumulation of bioactive lipids and modified lipoproteins in atherosclerotic foci.
In mice, sPLA2 expression significantly influences HDL particle size and composition and demonstrate that an induction of sPLA2 is required for the decrease in plasma HDL cholesterol in response to inflammatory stimuli. Instillation of bacteria into the bronchi was associated with surfactant degradation and a decrease in large:small ratio of surfactant aggregates in rats.

Cadherin-5 (CDH5) belongs to the atypical/type 2 subgroup of Cadherin homophilic adhesion proteins. Cadherin-5 is a calcium-dependent cell-cell adhesion molecule, which is comprised of 5 extracellular cadherin repeats, a transmembrane region and a highly conserved cytoplasmic tail. Cadherin-5 protein plays a role in the formation, maturation and remodeling of the vascular wall. CDH5 is generally considered to be specific for vascular endothelia in which it is either the sole or the predominant cadherin, often co-existing with N-cadherin. Moreover, the CDH5 protein regulates or is regulated by VEGF R2, type 1 and type 2 TGF-beta receptors, and other endothelial junction proteins such as JAM-C, Claudin-5, and N-Cadherin. CDH5 also connects with alpha-catenin forming a link to the cytoskeleton. CDH5 functions jointly with KRIT1 to create and maintain correct endothelial cell polarity and vascular lumen. Furthermore, Cadherin-5 is essential for activation of PRKCZ and for the localization of phosphorylated PRKCZ, PARD3, TIAM1 and RAP1B to the cell junction. The CDH5 gene is located in a gene cluster in a region on the long arm of chromosome 16 which is involved in loss of heterozygosity events in breast and prostate cancer.

Leukemia Inhibitory Factor Receptor Alpha or LIFR is a protein, part of the Interleukin-6 receptor group of proteins. As such, LIFR acts as a mediator for various proteins (IL-6, IL-11, IL-27, Oncostatin M etc). LIFR has many functions as a cytokine, he has an affect on the cell proliferation, differentiation and survival in the different stages of life. In different types of breast cancer LIFR is down regulated, and as such, can be used as a prognostic tool.

PTTG1 (Securin) is mainly involved in the regulation of sister chromatid separation during cell division. Securin is a regulatory protein, which has a central role in chromosome stability, in the p53/TP53 pathway, and DNA repair. Additional two roles have been identified for PTTG1; the first one is to facilitate the transport of separase (cysteine protease) to the nucleus and the second role is to hinder the catalytic activity of separase. PTTG1 is ubiquitinated by the APC (Anaphase Promoting Complex), and subsequently degraded by the Proteasome, releasing separase. During the mitosis, PTTG1 blocks Separase/ESPL1 function, thus preventing the proteolysis of the cohesin complex and the ensuing segregation of the chromosomes. However, PTTG1 function is not restricted to a blocking activity only, since it is required to activate ESPL1. PTTG1 is ubiquitinated at the beginning of anaphase, leading to its destruction and to the liberation of ESPL1.
PTTG1 contains two PXXP motifs, which are necessary for its transforming and tumorigenic activities, in addition to its stimulation of basic fibroblast growth factor expression. It also contains a D box (destruction box) which is essential for its degradation by the APC. The acidic C-terminal region of the Securin can function as a transactivation domain. Even though, PTTG1 is primarily a cytosolic protein, it partially localizes in the nucleus.
PTTG1 is highly expressed in various tumors; it also has transforming activity in vitro and tumorigenic activity in vivo. Furthermore, PTTG1 negatively regulates the transcriptional activity and related apoptosis activity of TP53.

PDIA3 is an enzyme that belongs to the endoplasmic reticulum and interacts with lectin chaperones calreticulin and calnexin to modulate folding of newly synthesized glycoproteins. PDIA3 has protein disulfide isomerase activity. Complexes of lectins and PDIA3 mediate protein folding by promoting formation of disulfide bonds in their glycoprotein substrates. PDIA3 is expressed in the lumbar spinal cord from rats submitted to peripheral lesion during neonatal period. PDIA3 interacts with thiazide-sensitive sodium-chloride cotransporter in the kidney and is induced by glucose deprivation. PDIA3 is part of the major histocompatibility complex (MHC) class I peptide-loading complex (TAP1), which is important for formation of the final antigen conformation and export from the endoplasmic reticulum to the cell surface.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

MGP is vital for the regulation of calcification in the extracellular matrix, particularly in cartilage and arteries. The K-dependent vitamin MGP has five to six residues of Gla, a Ca2+ binding amino acid crucial for vitamin K-dependent gamma carboxylase for its formation. MGP is formed by COOH-terminal processing by carboxypeptidase B-like enzymatic activity and localized in the human bone.

Activins are homodimers or heterodimers of the different β subunit isoforms, part of the TGFβ family. Mature Activin A has two 116 amino acids residues βA subunits (βA-βA). Activin displays an extensive variety of biological activities, including mesoderm induction, neural cell differentiation, bone remodelling, haematopoiesis, and reproductive physiology. Activins takes part in the production and regulation of hormones such as FSH, LH, GnRH and ACTH. Cells that are identified to express Activin A include fibroblasts, endothelial cells, hepatocytes, vascular smooth muscle cells, macrophages, keratinocytes, osteoclasts, bone marrow monocytes, prostatic epithelium, neurons, chondrocytes, osteoblasts, Leydig cells, Sertoli cells, and ovarian granulosa cells.

Myostatin (GDF-8), a member of the TGFbeta superfamily, is a potent and specific negative regulator of skeletal muscle mass. In serum, myostatin circulates as part of a latent complex containing myostatin propeptide and/or follistatin-related gene. The myostatin propeptide is known to bind and inhibit myostatin in vitro. This interaction is relevant in vivo, with a majority (>70%) of myostatin in serum bound to its propeptide. The myostatin propeptide is negative regulator of myostatin in vivo.

Dual specificity phosphatase 13 (DUSP13) is a member of the protein-tyrosine phosphatase family. DUSP13 cooperates with protein kinases to control cell proliferation and differentiation. DUSP13 is engaged in the regulation of meiosis and/or differentiation of testicular germ cells in the course of spermatogenesis. DUSP13 demonstrates intrinsic phosphatase activity towards both phospho-seryl/threonyl and -tyrosyl residues of myelin basic protein, with similar specific activities in vitro.

NFNB demonstrates the capability to reduce quinines. NFNB enzyme activates prodrugs in antibody directed enzyme prodrug therapy. NFNB reduces nitrofurazone, quinones and anti-tumor agent CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide). The reduction of CB1954 results in the generation of cytotoxic species.

Dual-Specificity Tyrosine-(Y)-Phosphorylation Regulated 1A (DYRK1A) belongs to the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family. DYRK1A includes a nuclear targeting signal sequence, a leucine zipper motif and a protein kinase domain. DYRK1A catalyzes its autophosphorylation on serine/threonine and tyrosine residues and takes part in a signaling pathway regulating cell proliferation. DYRK1A has a substrate preference for proline at position P+1 and arginine at position P-3.

PAPPA is a large zinc binding protein, which acts as a metalloprotease and specifically cleaves IGFBP-4 and IGFBP-5, resulting in release of bound IGF. PAPP-A can also act as a regulator of IGF bioactivity in a number of biological systems, including the human ovary and cardiovascular systems. It was shown that PAPP A levels are elevated in patients with unstable angina or acute myocardial infarction. Furthermore, PAPPA is believed to be involved in local proliferative processes such as wound healing and bone remodeling. Moreover, PAPP-A is produced in high concentrations during pregnancy and is released into the maternal circulation. In placenta, PAPP A is expressed in X cells in septa and anchoring villi, and in syncytiotrophoblasts in the chorionic villi.
Lower levels of PAPPA are found in an array of other tissues including kidney, myometrium, endometrium, ovaries, breast, prostate, bone marrow, colon, fibroblasts and osteoblasts. PAPP-A is present in serum and placenta during pregnancy; with levels increasing throughout pregnancy. Low levels of PAPP A are associated with a number of foetal chromosomal abnormalities, as well as pre-eclampsia and stillbirth.
PAPPA levels may be a potentially highly specific marker for heart disease.
PAPP-A proteolytic activity is inhibited by targeting substrate exosite binding.

PAPSS1 is a bifunctional enzyme with APS kinase and ATP sulfurylase activity. PAPSS1 facilitates two stages in the sulfate activation pathway, yielding 3'-phosphoadenylylsulfate (PAPS). Additionally, PAPSS1 takes part in the biosynthesis of sulfated L-selectin ligands in endothelial cells.

Chromosome 19 Open Reading Frame 80 (C19ORF80) is a significant new regulator of lipid metabolism which regulates serum triglyceride levels, possibly by promoting ANGPTL3 cleavage. C19ORF80 belongs to the ANGPTL protein family. C19ORF80 is a hormone which specifically promotes pancreatic beta cell proliferation and beta cell mass expansion, thus improving glucose tolerance. C19ORF80 is mainly expressed in the liver; it is also expressed in adipose tissues. C19ORF80 is expressed in response to food intake and stimulated by insulin.

TGFBR2 is part of the Ser/Thr protein kinase family and the TGFB receptor subfamily. TGFBR2 is a transmembrane protein that has a protein kinase domain, forms a heterodimeric complex with another receptor protein, and binds TGF-beta. This receptor/ligand complex phosphorylates proteins, which then enter the nucleus and regulate the transcription of a subset of genes related to cell proliferation. Mutations in TGFBR2 gene have been associated with Marfan syndrome, Loeys-Deitz Aortic Aneurysm Syndrome, and the development of various types of tumors. TGFBR2 expression is increased in oral squamous cell carcinoma cells. TGFBR2 attenuates the biological activities of TGF-beta in colorectal cancer. TGFBR2 expression is decreased by IL-1beta while inducing Sp3 via NFkappaB. TGFB2 and TGFBR2 are involved in the antiestrogenic activity of tamoxifen metabolites in breast cancer.

TNFRSF6B is a member of the Tumor necrosis factor receptor superfamily. TNFRSF6B performs as a decoy receptor which races against death receptors for ligand binding. TNFRSF6B has a regulatory role in suppressing FasL- and LIGHT-mediated cell death and T cell activation in addition to inducing angiogenesis via neutralization of TL1A.

GTP Cyclohydrolase I Feedback Regulator, also known as GCHFR, is a Protein coding gene which includes a homodimer. GCHFR binds and mediates tetrahydrobiopterin inhibition of GTP cyclohydrolase I. GCHFR also regulates phenylalanine metabolism in the liver and in the production of biogenic amine neurotransmitters and nitric oxide.