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Deoxyuridine Triphosphatase (DUT) is a ubiquitous enzyme that functions in nucleotide metabolism. Deoxyuridine Triphosphatase, in the presence of magnesium ions, is responsible for hydrolyzing dUTP to dUMP and diphosphate. This reaction is imperative for keeping the intracellular dUTP concentration low so that uracil does not become incorporated into DNA. Extensive integration of uracil into DNA can eventually lead to cell death. This suggests that DUT is crucial for cell viability, further implying that it is a prospective target for anticancer therapy.

OXSM, a beta-ketoacyl synthetase, is essential for elongation of fatty acid chains in the mitochondria. Alternatively spliced transcript variants were found.

Cytidine deaminase (CDA) is an enzyme that scavenges exogenous and endogenous cytidine and 2'-deoxycytidine for UMP synthesis. CDA is one of several deaminases responsible for maintaining the cellular pyrimidine pool. CDA also catalyzes the deamination of chemotherapeutic cytosine nucleoside analogs such as Ara-C and 5-azacytidine, which results in the loss of their cytotoxic and antitumor function. CDA can form homotetramers and is generally expressed in granulocytes. Mutations in the CDA gene are linked to decreased sensitivity to the cytosine nucleoside analogue cytosine arabinoside used in the treatment of certain childhood leukemias.

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 is secreted when eating, nursing, mating, estrogen treatment and during ovulation. Prolactin's primary role is to promote and maintain lactation but also plays a role in breast cancer development, regulation of reproductive function and immunoregulation.

Glycine amidinotransferase mitochondrial (GATM) is a mitochondrial enzyme which is a member of the amidinotransferase family. The GATM enzyme is involved in creatine biosynthesis, where it catalyzes the transfer of a guanido group from L-arginine to glycine, resulting in guanidinoacetic acid, the immediate precursor of creatine, which has an imperative role in energy metabolism in muscle tissues. GATM is significant in embryonic and central nervous system development. GATM gene mutations cause arginine:glycine amidinotransferase deficiency, an inborn error of creatine synthesis characterized by mental retardation, language impairment, and behavioral disorders.

Cyclophilin B (also known as PPIB, peptidylpropyl isomerase B) is a cyclosporine-binding protein and is mainly located within the endoplasmic reticulum. It is associated with the secretory pathway and released in biological fluids. This protein can bind to cells derived from T- and B-lymphocytes, and may regulate cyclosporine A-mediated immunosuppression.

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.

Tyrosyl-DNA phosphodiesterase 1 ( TDP1) is required for repairing stalled topoisomerase I-DNA complexes by catalyzing the hydrolysis of the phosphodiester bond between the tyrosine residue of topoisomerase I and the 3-prime phosphate of DNA. TDP1 also detach glycolate from single-stranded DNA having 3-prime phosphoglycolate, suggesting a role in repair of free-radical mediated DNA double-strand breaks.

GH is a member of the prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the GH locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five GHs, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the GH locus. Mutations in or deletions of the gene lead to GH deficiency and short stature.

UGDH is part of the UDP-glucose/GDP-mannose dehydrogenase family and is a widely expressed enzyme localized in the liver. UGDH transfers UDP-glucose to UDP-glucuronate and thus takes part in the biosynthesis of glycosaminoglycans such as hyaluronan, chondroitin sulfate, and heparan sulfate. These glycosylated products are ordinary molecules of the extracellular matrix and participate in signal transduction, cell migration, and cancer growth and metastasis.

AKR1C1 transfers progesterone to its inactive state or in other words catalyzes the reaction of 20-alpha-hydroxy progesterone (20-alpha-OHP). In the liver and intestine. AKR1C1 transfers bile and monitors the intrahepatic bile acid concentration though it has a low bile-binding ability. AKR1C1 participates in myelin formation. AKR1C1 is part of the aldo/keto reductase superfamily, which has over 40 known enzymes which catalyze the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors thus display overlapping but distinct substrate specificity.

Acyl-CoA synthetase family member 2, also known as ACSF2 is a member of the ATP-dependent AMP-binding enzyme family. Acyl-CoA synthetases are a family of enzymes which catalyze the thioesterification of fatty acids with coenzymeA to form activated intermediates, which play a basic part in lipid metabolism as well as homeostasis of lipid-related processes. ACSF2 is required for the complex of lipid synthesis, energy production via beta-oxidation, protein acylation and fatty-acid dependent transcriptional regulation. Moreover, ACSF2 is required for fatty acid import into cells by the process of vectorial acylation.

Antioxidant enzyme Glutathione S- Transferase (GST) is thought to do the primary cellular defense mechanism against reactive oxygen species. GST reduces lipid hydroperoxides through its Se-independent glutathione peroxidase activity. The enzyme also detoxifies lipid peroxidation end products such as 4-hydroxynonenal (4-HNE).
The soluble GST is a 26 kDa protein which occurs as a dimer in all aerobic organisms. Each monomer has two domains, one that binds GSH and is an /-structure similar to thioredoxin and the other, all helical, that binds the hydrophobic substrate. The GST -fusion protein expression system is a widely used recombinant protein expression system that allows a peptide or a regulatory protein domain to be expressed as a fusion to the C-terminus of Schistosoma japonicum GST. Fusion proteins also possess GST -enzymatic activity and can undergo dimerization similar to in vivo. The fusion protein can be purified via GST -affinity column chromatography. In most cases, the desired peptides or domains are removed from GST by applying a specific protease that recognizes and cleaves the linker between the protein domain and GST. The technique has been widely used to generate different kinds of proteins for crystallization, molecular immunology studies, the production of vaccines and studies involving protein-protein and protein-DNA interactions.

GDA is a member of the ATZ/TRZ family and is in charge for the hydrolytic deamination of guanine. GDA takes part in microtubule assembly. Multiple transcript variants encoding different isoforms have been found for GDA.

Matrix metalloproteinases are a family of zinc and calcium-dependent endopeptidases that break down extracellular matrix proteins. The MMP9 is secreted as a 92kDa zymogen. Cleavage of ProMMP-9 results in the active enzyme, having a molecular weight of approximately 82kDa. MMP9 is composed of the following domains: a gelatin-binding domain consisting of three fibronectin type II units, a catalytic domain containing the zinc-binding site, a proline-rich type V collagen-homologous domain and a hemopexin-like domain. MMP9 is produced by the several cell types: monocytes, macrophages, neutrophils, keratinocytes, fibroblasts, osteoclasts and endothelial cells. MMP9 is involved in inflammatory responses, tissue remodeling, wound healing, tumor growth and metastasis. MMP9 may also play an important part in local proteolysis of the extracellular matrix and in leukocyte migration, as well as in bone osteoclastic resorption. MMP9 cleaves type IV and type V collagens into large C-terminal three quarter fragments and shorter N-terminal one quarter fragments. MMP9 can also degrade fibronectin but not laminin or Pz-peptide.
MMP9 defects may be a cause of susceptibility to intervertebral disc disease (IDD), also known as lumbar disk herniation (LDH).

PRSS3 is a trypsinogen, and a member of the trypsin family of serine proteases. PRSS3 is expressed in the pancreas and brain and is unaffected by common trypsin inhibitors. It is active on peptide linkages involving the carboxyl group of lysine or arginine. PRSS3 is restricted to the locus of T cell receptor beta variable orphans on chromosome 9. 4 different isoforms encoded by 4 transcript variants were identified for this gene.

Magnesium-dependent phosphatase 1 (MDP1) is a memeber of the HAD-like hydrolase superfamily. MDP1 is a magnesium-dependent phosphatase which may act as a tyrosine phosphatase. MDP1 is inhibited by vanadate and zinc, and slightly by calcium.

Aldo-Keto Reductase Family 7 Member A3 or AKR7A3, is an enzyme, it is part of the detoxification of aldehydes and ketones process. AKR7A3 diminishes the dialdehyde protein-binding form of aflatoxin B1 to the non-binding AFB1 dialcohol. The enzyme takes partin protection of liver from toxic and carcinogenic effects of AFB1, a potent hepatocarcinogen.

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.

SHMT1 is a member of the SHMT family. SHMT1 is the cellular form of serine hydroxymethyltransferase, a pyridoxal phosphate-containing enzyme which catalyzes the reversible conversion of serine and tetrahydrofolate to glycine and 5 10-methylene tetrahydrofolate. In addition, SHMT1 specifically provides one-carbon units for thymidylate biosynthesis, reduces methylenetetrahydrofolate pools for S-adenosylmethionine (SAM) synthesis by synthesizing serine, sequesters 5-methyltetrahydrofolate and inhibits SAM synthesis.

SULT2A1 is a member fo the sulfotransferase family. SULT2A1 is primarily expressed in liver and adrenal tissues, and to a lesser extent in kidney. SULT2A1 catalyzes the 3'-phosphoadenosine 5'-phosphosulfate-dependent sulfation of an extensive selection of steroids in human liver and adrenal tissues, and in addition is responsible for a larg number of the sulfation of bile acids in human liver.

GSTT2 belongs to the glutathione s-transferase (GST) family of proteins. There are eight GST proteins families, named alpha, kappa, mu, omega, pi, sigma, theta and zeta. Each one of the GST families has several proteins with different functions throughout the cell. The theta type members GSTT1 and GSTT2 have a 55% aa sequence homology and hold a vital role in human carcinogenesis. The theta genes are structurally similar – each has five exons with identical exon/intron boundaries.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex assembly factor 4 (NDUFAF4) is involved in the compilation of mitochondrial NADH: ubiquinone oxidoreductase complex (complex I). In addition, NDUFAF4 is involved in cell proliferation and survival of hormone-dependent tumor cells. NDUFAF4 may also be a regulator of breast tumor cell invasion. NDUFAF4 gene mutations cause the mitochondrial complex I deficiency.

Caspase 3 Apoptosis-Related Cysteine Peptidase (CASP3) belongs to the cysteine-aspartic acid protease (caspase) family. Sequential activation of caspases plays a key role in the execution-phase of cell apoptosis. Caspases exist as inactive proenzymes which undergo proteolytic processing at conserved aspartic residues to generate 2 subunits, large and small, that dimerize to create the active enzyme. CASP3 protein cleaves and activates caspases 6, 7 and 9, and the protein itself is processed by caspases 8, 9 and 10. CASP3 is the leading caspase involved in the cleavage of amyloid-beta 4A precursor protein, which is linked with neuronal death in Alzheimer's disease. In addition, CASP3 is involved in the cleavage of huntingtin. CASP3 also cleaves and activates sterol regulatory element binding proteins (SREBPs) between the basic helix-loop-helix leucine zipper domain and the membrane attachment domain. CASP3 initiates cell adhesion in sympathetic neurons through RET cleavage.